Chlorhexidine

Background: There is evidence that dentine matrix gelatinases are involved in the destruction of carious dentine after demineralization by bacterial acids. It has also been observed that chlorhexidine, in very low concentrations, inhibits the activity of these enzymes in mammalian cells. The goal of this study was to determine if the gelatinase activity of carious dentine may be inhibited by chlorhexidine in clinical use concentrations. Methods: Gelatinolytic activity was evaluated through zymography and identified by Western blot. The inhibitory effects of chlorhexidine at concentrations of 0.01%, 0.04%, 0.08% and 1% on the enzymatic activity of softened carious dentine samples were determined. Results: In carious dentine, five bands of gelatinolytic activity were detected, with molecular sizes of 86, 75, 38, 33 and 32 kDa. The two bands of the greatest molecular size corresponded to latent and active metalloproteinase-9, respectively. Concentrations of chlorhexidine that were greater than or equal to 0.04% were sufficient to inhibit gelatinolytic activity in the observed bands of carious dentine. Conclusions: These results support the use of chlorhexidine in clinical use concentrations for the treatment and control of dentine caries. Our study demonstrates for the first time the inhibitory effect of chlorhexidine on gelatinases from carious human dentine.

BackgroundThere is evidence that dentine matrix gelatinases are involved in the destruction of carious dentine after demineralization by bacterial acids. It has also been observed that chlorhexidine, in very low concentrations, inhibits the activity of these enzymes in mammalian cells. The goal of this study was to determine if the gelatinase activity of carious dentine may be inhibited by chlorhexidine in clinical use concentrations.MethodsGelatinolytic activity was evaluated through zymography and identified by Western blot. The inhibitory effects of chlorhexidine at concentrations of 0.01%, 0.04%, 0.08% and 1% on the enzymatic activity of softened carious dentine samples were determined.ResultsIn carious dentine, five bands of gelatinolytic activity were detected, with molecular sizes of 86, 75, 38, 33 and 32 kDa. The two bands of the greatest molecular size corresponded to latent and active metalloproteinase‐9, respectively. Concentrations of chlorhexidine that were greater than...

N eonatal sepsis in one of the leading causes of death in neonates in developing countries. Infection of the umbilical cord often leads to infection in the blood. WHO recommends 4% chlorhexidine to prevent ompha-1 litis and neonatal sepsis. In Pakistan we use methylated spirit for prophylaxis of omphalitis as 4% chlorhexidine is not available and expensive to use. Some commercial gels containing 2% chlorhexidine are available, but these are not as effective as methylated spirit. Chlorhexidine gel is an antiseptic agent with broadspectrum bactericidal and bacteriostatic properties effective against gram-negative bacteria and fungi with rapid pathogen killing rates. Methylated spirit on the other hand is both bactericidal, mycobactericidal, fungicidal 2-5 and viricidal. In Pakistan Staphylococcal aureus is common pathogen in umbilical discharge. Some low cost prevention therapy should be used. Methylated spirit is commonly used for cord care. A study was conducted to explore about cord care practices in African setting which showed that 73.2% respondents consider methy-6 lated spirit as most important agent for cord care. Chlorhexidine is available in different concentrations for antiseptic purpose. Efficacy of all concentrations is comparable but 4% chlorhexidine concentration is more effective in inhibiting organism's flora as compared to 2% chlorhexidine. Since then, multiple studies were done to compare methylated spirit and 4% chlorhexidine. Methylated spirit is equally safe where 4% chlorhexidine 7 is unavailable. In Pakistan 57% deaths occur in neonatal period. Pakistan has highest neonatal mortality 8 rate of 42 per 1000 live births. In developing countries

The aim of the present investigation was to compare the efficacy of mineral trioxide aggregate (MTA) and 0.2% chlorhexidine (CHX) mixture to pure MTA, as a pulp capping material. The pulp of 24 lateral incisors and canines from four dogs were exposed and capped either with MTA or MTA+0.2% CHX. After 2 months the animals were sacrificed and the teeth were prepared for histological evaluation in terms of calcified bridge formation, the degree of inflammation and presence of necrosis. The Fisher's exact test was used for data analysis. The results showed that formation of complete calcified bridge in MTA specimens was significantly more than MTA+CHX (P<0.05). No significant difference was found in the degree of inflammation and necrosis between MTA and MTA+CHX groups (P>0.05). Mixing MTA with CHX as pulp capping agent had a significant negative impact on formation of calcified bridge on directly capped dog's teeth.

RESUMEN Introducción: El uso de alcohol y otros antisépticos para la cura del cordón umbilical está ampliamente extendido. No hay unidad entre los centros y profesionales sobre cuál es la mejor manera de realizar la cura del cordón umbilical.

Aims: The representativeness of European standards phase 2, step 1 regarding bactericidal and yeasticidal activities was used for the comparison of two marketed antiseptic solutions, one containing chlorhexidine digluconate (0.5%) and the other combining chlorhexidine digluconate (0.25%), benzalkonium chloride (0.025%) and benzylic alcohol (4%). Methods: The bactericidal activity of the antiseptic solutions used pure or diluted was assessed according to the European standards NF EN 13727 and NF EN 13624 for the bactericidal and yeasticidal activity respectively. The contact time was 1 min at 20˚C. Interfering substances used correspond to soiling conditions i.e. bovine serum albumin and sheep erythrocytes. A reduction of colony-forming units by ≥5 log10 was deemed to meet the requirements to conclude bactericidal activity and ≥4 log10 for yeasticidal activity. Results: Regarding all the mandatory strains, both solutions are bactericidal and yeasticidal even after a 40% dilution and even under "dirty" conditions. Conclusions: The present study demonstrated the efficient bactericidal and yeasticidal activity of aqueous solutions containing chlorhexidine digluconate either alone at a concentration of 0.5% (w/v) or at a concentration of 0.25% (w/v) when combined with benzalkonium chloride at 0.025% (w/v) and benzylic alcohol 4%. These results have to be considered regarding the respective formulations and potent allergy risks.

Aim: To determine the in vitro bactericidal activity of different chlorhexidine (CHX)-based commercial mouthwash products claiming different chlorhexidine concentrations under conditions similar to their use. Method: Bactericidal assays were performed using four major bacterial species implicated in periodontal disease: Fusobacterium nucleatum CIP101130, Aggregatibacter actinomycetemcomitans CIP 52.106T, Prevotella intermedia CIP 103607, and Porphyromonas gingivalis CIP 103683. Seven commercially available mouthwash products were chosen, each containing CHX digluconate (concentrations ranged from 0.1% to 0.2%) as the principle active ingredient. Assays were performed according to European guidelines for antiseptics (with modifications to mimic conditions of use) by exposing bacterial suspensions to the mouthwash solutions for 1 min ± 5 seconds at 32 ± 1°C in the presence of an interfering substance (artificial saliva). The log reduction in bacterial count was determined. Results: Five of the tested mouthwashes were defined as bactericidal to each of the four test strains (log reduction ≥ 5). However, two mouthwashes were not defined as bactericidal to all test strains (log reduction <5). In one case, a 0.12% CHX mouthwash was not bactericidal towards A. actinomycetemcomitans. In the other case, a 0.2% CHX mouthwash was not bactericidal towards two test strains, A. actinomycetemcomitans and P. intermedia. Conclusions: This study emphasizes that antimicrobial activity of CHX-based mouthwash products is not determined lonely by the CHX concentration, but by all the components of the formulation as a whole. Indeed, interactions between CHX and the different components, and not only alcohol, may affect antibacterial activity positively or negatively.

Objectives: to assess the effect of an educational intervention based on clinical simulation on nursing professionals’ compliance with practices to prevent peripherally inserted central venous catheter-associated primary bloodstream infections in a Neonatal Intensive Care Unit. Methods: a quasi-experimental study, with preand post-intervention assessment with a single group. The population consisted of 41 nursing professionals, with 31 observations being made before and after the intervention. Analyzes were performed using descriptive statistics and the McNemar non-parametric test. A significance level of 5% was adopted. Results: after the intervention, there was an increase in compliance with prevention practices of surgical antisepsis and professional hand hygiene, skin antisepsis with chlorhexidine, waiting for the time of the effect of alcoholic chlorhexidine and compliance with the sterile technique. Conclusions: the educational intervention showed an effect on increasing compl...

Background and Aim: The emergence of methicillin-resistant Staphylococcus aureus (MRSA) as a highly pathogenic strain in veterinary and human medicine is a growing global problem. This study aimed to evaluate MRSA isolates of human and animal origin against various antibiotics in Yogyakarta, Indonesia. Materials and Methods: The susceptibility test was carried out by the disk diffusion method using Mueller-Hinton agar against nine antibiotic disks. Methicillin-resistant S. aureus strains were genetically confirmed through mecA gene detection encoding for methicillin resistance by polymerase chain reaction. Results: All 240 S. aureus strains isolated from animals and humans were resistant to penicillin G (P) (100% and 99%, respectively), followed by ampicillin (AMP), amoxicillin (AML), oxacillin (OX), erythromycin (E), clindamycin (DA), tetracycline (TE), gentamicin (GEN), and ciprofloxacin (CIP). Eighty-three MRSA strains were resistant to OX (100%), P (100%), AMP (99.27%), AML (95.52%), E (87.77%), TE (71.33%), DA (63.24%), GEN (38.81%), and CIP (26.87%). Conclusion: The antimicrobial resistance pattern of S. aureus human isolates was similar to their animal counterpart, with 77.20% of MRSA strains classified as multidrug-resistant (MDR) bacteria. These findings indicate an increase in MDR S. aureus strains of animal origin in Yogyakarta, thus raising public health concerns about MRSA zoonotic spread.

E-101 solution is a first-in-class myeloperoxidase containing antimicrobial solution developed for topical application. The active ingredients in E-101 solution are two enzymes, porcine myeloperoxidase (pMPO) and glucose oxidase (GO) in an aqueous solution and activated by the addition of a glucose solution. Once activated, the reactive species hydrogen peroxide, hypochlorous acid/hypochlorite (HOCl/OCl-), and singlet oxygen (1 O 2) are generated. We evaluated the effect of whole human blood on the performance of E-101 solution compared to commercially available wound antiseptics and commonly used biocides. The wound cleansers NeutroPhase, Microcyn, and Vashe with the active HOCl/OClcomponent were tested according to the USP-51 effectiveness test in the presence of 0, 1, 2 and 5% blood. Comparative time-kill studies against chlorhexidine, povidone-iodine, sodium oxychlorosene were tested in the presence of 0, 2, 5 10, and 20% blood. In the USP-51 test, E-101 solution demonstrated >2 log10 reduction against bacterial and fungal isolates in the presence of 5% blood at days 14 and 28. With the exception of NeutroPhase activity against S. aureus, all comparable wound antiseptics demonstrated <2 log10 reduction in the presence of 5% blood at days 14 and 28. Time-kill microbicidal data observed in the presence of blood demonstrated that E-101 solution was the most active biocide, followed by chlorhexidine and povidone-iodine. The presence of 2% blood completely inhibited the activity of sodium oxychlorosene. In summary, E-101 solution remained active in the presence of blood containing catalase and other substances that competitively react with 1 O 2 and HOCl/OClas a safe and effective wound antiseptic.

With the increasing incidence of diseases and development of antibiotic resistance, the alternative, safe, effective, and economical products are the need of time. Proven in multiple clinical studies, Aloe vera has been used in antimicrobial activity and used in mouth ulcers, periodontal diseases etc. In this present study Mucoadhesive film was prepared to study antimicrobial activity, to improve therapeutic efficacy by its adhesive action. The present study discusses the estimation of the antimicrobial activity of Aloe vera loaded mucoadhesive films. The formulation was studied for percent inhibition of microorganism of inflammed tissue, Calculas, and cultures of S.oralis, C.albicans, S.mutans. The formulation showed Percent inhibition of Candida albicans more when compared with standard Chlorhexidine. The film prepared is economic, convenient and shows the antimicrobial activity.

With the increasing incidence of diseases and development of antibiotic resistance, the alternative, safe, effective, and economical products are the need of time. Proven in multiple clinical studies, Aloe vera has been used in antimicrobial activity and used in mouth ulcers, periodontal diseases etc. In this present study Mucoadhesive film was prepared to study antimicrobial activity, to improve therapeutic efficacy by its adhesive action. The present study discusses the estimation of the antimicrobial activity of Aloe vera loaded mucoadhesive films. The formulation was studied for percent inhibition of microorganism of inflammed tissue, Calculas, and cultures of S.oralis, C.albicans, S.mutans. The formulation showed Percent inhibition of Candida albicans more when compared with standard Chlorhexidine. The film prepared is economic, convenient and shows the antimicrobial activity.

Objectives: Chlorhexidine is used as a disinfectant to prevent surgical infections. Recently, studies have indicated that chlorhexidine usage has selected methicillin-resistant Staphylococcus aureus strains that are tolerant to chlorhexidine and that this may be related to the presence of the qacA/B-encoded efflux pumps. Here, we evaluated if high-level exposure to chlorhexidine selects for tolerant colonizing Staphylococcus epidermidis and we addressed the consequences of long-term exposure to chlorhexidine. Methods: Chlorhexidine susceptibility and carriage of qacA/B was determined for colonizing S. epidermidis isolated from scrub nurses heavily exposed to chlorhexidine and were compared with isolates from non-users of chlorhexidine hand rubs. S. epidermidis blood isolates from the 1960s, before the wider introduction of chlorhexidine to the market, were also tested and compared with recently collected S. epidermidis blood isolates. Results: There was no correlation between the use of chlorhexidine in scrub nurses and the presence of qacA/B genes in S. epidermidis isolates or increased MICs/MBCs of chlorhexidine for S. epidermidis isolates. While 55% of current blood isolates harboured the qacA/B genes, none of the 33 historical S. epidermidis isolates did, although their MICs and MBCs of chlorhexidine were comparable to those for current isolates. Conclusions: Chlorhexidine used as a hand rub does not select for S. epidermidis isolates with increased MICs or MBCs of chlorhexidine. However, the absence of qacA/B genes in S. epidermidis isolates obtained in the 1960s suggests that long-term use of biocides like chlorhexidine or related compounds may select for the presence of qacA/B genes.

Objectives: Chlorhexidine is used as a disinfectant to prevent surgical infections. Recently, studies have indicated that chlorhexidine usage has selected methicillin-resistant Staphylococcus aureus strains that are tolerant to chlorhexidine and that this may be related to the presence of the qacA/B-encoded efflux pumps. Here, we evaluated if high-level exposure to chlorhexidine selects for tolerant colonizing Staphylococcus epidermidis and we addressed the consequences of long-term exposure to chlorhexidine. Methods: Chlorhexidine susceptibility and carriage of qacA/B was determined for colonizing S. epidermidis isolated from scrub nurses heavily exposed to chlorhexidine and were compared with isolates from non-users of chlorhexidine hand rubs. S. epidermidis blood isolates from the 1960s, before the wider introduction of chlorhexidine to the market, were also tested and compared with recently collected S. epidermidis blood isolates. Results: There was no correlation between the use of chlorhexidine in scrub nurses and the presence of qacA/B genes in S. epidermidis isolates or increased MICs/MBCs of chlorhexidine for S. epidermidis isolates. While 55% of current blood isolates harboured the qacA/B genes, none of the 33 historical S. epidermidis isolates did, although their MICs and MBCs of chlorhexidine were comparable to those for current isolates. Conclusions: Chlorhexidine used as a hand rub does not select for S. epidermidis isolates with increased MICs or MBCs of chlorhexidine. However, the absence of qacA/B genes in S. epidermidis isolates obtained in the 1960s suggests that long-term use of biocides like chlorhexidine or related compounds may select for the presence of qacA/B genes.

Dentists often note problems with infection in patients with maxillofacial prostheses. Conventional disinfection protocols are not always effective and may alter the properties of the polymer used in the prosthesis. Thus, the search for improved disinfection methods is important. The purpose of this in vitro study was to evaluate and compare the antimicrobial activity of conventional disinfectant solutions (water and neutral soap and 4% chlorhexidine) and plant extracts (Cymbopogon nardus and Hydrastis canadensis) on specimens of maxillofacial silicone contaminated with Candida albicans and Staphylococcus aureus biofilms. Seventy-two silicone (MDX4-4210) specimens were fabricated (5×2 mm) and sterilized. Thirty-six were contaminated with C albicans (10(6) cells/mL) and 36 with S aureus (10(8) cells/mL) to evaluate the antimicrobial activity of the cleaning protocols. After incubation (37°C/72 hours), the specimens were divided into 5 groups: not disinfected (positive control), soaki...

The purpose of this study was to evaluate the color stability of a maxillofacial elastomer with the addition of a nanoparticle pigment and/or an opacifier submitted to chemical disinfection and artificial aging. Specimens were divided into four groups (n = 30): group I: silicone without pigment or opacifier, group II: ceramic powder pigment, group III: Barium sulfate (BaSO 4) opacifier, and group IV: ceramic powder and BaSO 4 opacifier. Specimens of each group (n = 10) were disinfected with effervescent tablets, neutral soap, or 4% chlorhexidine gluconate. Disinfection was done three times a week during two months. Afterward, specimens were submitted to different periods of artificial aging. Color evaluation was initially done, after 60 days (disinfection period) and after 252, 504, and 1008 h of artificial aging with aid of a reflection spectrophotometer. Data were analyzed by three-way ANOVA and Tukey test (α = 0.05). The isolated factor disinfection did not statistically influence the values of color stability among groups. The association between pigment and BaSO 4 opacifier (GIV) was more stable in relationship to color change (E). All values of E obtained, independent of the disinfectant and the period of artificial aging, were considered acceptable in agreement with the norms presented in literature. C 2011 Society of Photo-Optical Instrumentation Engineers (SPIE).

The purpose of this study was to evaluate persistent activity of three alcohol-based antiseptics widely used in the clinical routine containing chlorhexidine, triclosan or mecetronium after hand disinfection. Four tests were used to evaluate the antimicrobial activity of antiseptics on: (i) resident microbiota; (ii) nutrient agar plates (NAP) subsequently inoculated with a test organism; and transient microbiota acquired by contact with dry hands (iii), or (iv) a wet inert surface that had been artificially contaminated. Four reference strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis) and an Acinetobacter baumannii strain responsible for a hospital outbreak were used as transient microbiota. Antimicrobial activity was calculated according to the CFUs reduction by reference to non-disinfected control hands. The antiseptics were applied according to European Standard EN1500. Solutions containing chlorhexidine or triclosan showed some persistent effects on transient microbiota on inert humid surfaces and NAP, but not on contaminated dry hands. Solutions containing mecetronium showed no persistent effect on transient flora in any of the trials. All alcohol-based antiseptics tested were more effective against resident flora than soap. No persistent activity was observed for A. baumannii in any of the trials. Chlorhexidine and triclosan are preferred when an antiseptic with persistent activity is desired, but a moist environment appears to be necessary for that antibacterial activity. Accordingly, relevant conclusions regarding the persistent activity of antiseptics for clinical practice and protection against bacterial contamination cannot be derived from this study for the alcoholic solutions tested.

Background: Oil pulling is an oral hygiene practice and is described in the ancient Ayurvedic literature. Materials and Methods: A total of 30 subjects with plaque related mild-moderate gingivitis in the age Group of 18-25 was recruited and they were divided into two Groups as Group A and B, each with 15 subjects. Group A subjects were advised to practice coconut oil pulling therapy and Group B subjects were advised to use Chlorhexidine Gluconate 0.12% solution for 4 weeks as an adjuvant practice along with routine tooth brushing. Estimation of salivary Aspartate Aminotransferase was done at pre and post intervention stage for both the study Groups by using semi auto analyser. Results: Statistically significant reduction in the reduction in the salivary Aspartate Aminotransferase level was seen at post intervention stage in Group A and Group B compared to preintervention stage. Comparison of salivary Aspartate Aminotransferase level between Group A subjects and Group B subjects at pre and post intervention stage revealed no significant difference. Our study results show that oil pulling utilizing coconut oil is effective in reducing the severity of plaque induced mild-moderate gingivitis and the effect is comparable to 0.12% chlorhexidine mouthwash in reducing plaque formation and gingivitis. Conclusion: Oil pulling utilizing coconut oil is an effective adjuvant oral hygiene practice in reducing the severity of plaque induced mild-moderate gingivitis along with the routine oral hygiene measure. Coconut oil pulling practice could be a potential alternative to chlorhexidine mouth wash for long term use.

Background: Oil pulling is an oral hygiene practice and is described in the ancient Ayurvedic literature. Materials and Methods: A total of 30 subjects with plaque related mild-moderate gingivitis in the age Group of 18-25 was recruited and they were divided into two Groups as Group A and B, each with 15 subjects. Group A subjects were advised to practice coconut oil pulling therapy and Group B subjects were advised to use Chlorhexidine Gluconate 0.12% solution for 4 weeks as an adjuvant practice along with routine tooth brushing. Estimation of salivary Aspartate Aminotransferase was done at pre and post intervention stage for both the study Groups by using semi auto analyser. Results: Statistically significant reduction in the reduction in the salivary Aspartate Aminotransferase level was seen at post intervention stage in Group A and Group B compared to preintervention stage. Comparison of salivary Aspartate Aminotransferase level between Group A subjects and Group B subjects at pre and post intervention stage revealed no significant difference. Our study results show that oil pulling utilizing coconut oil is effective in reducing the severity of plaque induced mild-moderate gingivitis and the effect is comparable to 0.12% chlorhexidine mouthwash in reducing plaque formation and gingivitis. Conclusion: Oil pulling utilizing coconut oil is an effective adjuvant oral hygiene practice in reducing the severity of plaque induced mild-moderate gingivitis along with the routine oral hygiene measure. Coconut oil pulling practice could be a potential alternative to chlorhexidine mouth wash for long term use.

Background: Oil pulling is an oral hygiene practice and is described in the ancient Ayurvedic literature. Materials and Methods: A total of 30 subjects with plaque related mild-moderate gingivitis in the age Group of 18-25 was recruited and they were divided into two Groups as Group A and B, each with 15 subjects. Group A subjects were advised to practice coconut oil pulling therapy and Group B subjects were advised to use Chlorhexidine Gluconate 0.12% solution for 4 weeks as an adjuvant practice along with routine tooth brushing. Estimation of salivary Aspartate Aminotransferase was done at pre and post intervention stage for both the study Groups by using semi auto analyser. Results: Statistically significant reduction in the reduction in the salivary Aspartate Aminotransferase level was seen at post intervention stage in Group A and Group B compared to preintervention stage. Comparison of salivary Aspartate Aminotransferase level between Group A subjects and Group B subjects at pre and post intervention stage revealed no significant difference. Our study results show that oil pulling utilizing coconut oil is effective in reducing the severity of plaque induced mild-moderate gingivitis and the effect is comparable to 0.12% chlorhexidine mouthwash in reducing plaque formation and gingivitis. Conclusion: Oil pulling utilizing coconut oil is an effective adjuvant oral hygiene practice in reducing the severity of plaque induced mild-moderate gingivitis along with the routine oral hygiene measure. Coconut oil pulling practice could be a potential alternative to chlorhexidine mouth wash for long term use.

Antimicrobial screening of several lichen species and subsequent isolation and structure elucidation of active compounds revealed that the hydrolysis products of certain lichen metabolites, i.e., depsides, were active against gram-negative bacteria and fungi as well as gram-positive bacteria. The active constituents isolated from Stereocaulon alpinum and Peltigera aphthosa were identified, respectively, as methyl beta-orsellinate and a mixture of methyl and ethyl orsellinates. MIC determinations indicated that activity of these compounds was superior to that of the commonly used preservative agents methyl and propyl p-hydroxybenzoates and was of the same order as that of chlorocresol.

A device for the continuous collection of urine from newborn infants is described. This apparatus replaces the nursing tray of the Vickers 59 incubator. Collection of urine in the newborn infant is notoriously difficult, especially if prolonged collection is required for either diagnostic or research purposes. Various methods previously used depend on modifications of urine or colostomy bags, which tend to copyright.

Amino groups of cell envelope proteins, lipids, and lipopolysaccharides cannot be labeled in intact cells of Salmonella typhimurium G 30 by using 5-diznethylaminonaphthalene-l-sulfonylchloride incorporated in lecithin-cholesterol vesicles. However, application of membrane-interacting agents like tris(hydroxymethyl)aminomethane (Tris)-hydrochloride, ethylenediaminetetraacetate (Na salt) (EDTA), divalent cations, and sublethal doses of the cationic antibacterial agents polymyxin B and chlorhexidine induced specific fluorescent labeling of envelope proteins and lipids but not of cytoplasmic compounds, with the exception of a soluble protein with a molecular weight of 46,000 in sodium dodecyl sulfatepolyacrylamide gel electrophoresis. Treatment with Tris-hydrochloride buffer produced labeling of the heat-modifiable protein B/B+ and of proteins with molecular weights of 26,000, 22,000, and below 17,000. A combination of Trishydrochloride and EDTA induced additional dansylation of the major protein A and of proteins of molecular weights 80,000, 60,000, and 44,000. Polymyxin B and chlorhexidine caused similar labeling patterns. In every case, except with divalent cation treatment, protein B/B+ was the most prominently labeled species. Phosphatidylethanolamine was dansylated up to 30%. Lipopolysaccharide was not reactive under any condition or treatment. In addition, the peptidoglycan-bound lipoprotein did not react with dansylchloride in either intact or Tris-hydrochloride-treated cells. The results are discussed with regard to a possible localization of labeled and unlabeled compounds of the cell envelope on the basis of a model placing cell envelope amino groups into ion-ion interactions with anionic components of other envelope compounds like phosphate and carboxyl groups.

The objective of this study was to evaluate the efficacy of two novel alcohol-free oral rinses: polyhexamethylene biguanide-botanical oral rinse (PBOR) and chlorhexidine gluconate-botanical oral rinse (CBOR), against common ventilator-associated pneumonia (VAP) pathogens using in vitro methods and compare their antimicrobial activity to commercially available oral care products viz. Listerine, Scope and Gum. PBOR and CBOR were highly effective in rapid-kill (15s exposure) tests against VAP pathogens. PBOR, CBOR and Gum displayed equivalent prophylactic antimicrobial activity. In vitro artificial-teeth model showed that PBOR and CBOR were significantly effective against S. aureus and P. aeruginosa compared to others (P <0.05). SEM images revealed that PBOR and CBOR show efficacy in inhibiting biofilm forming P. aeruginosa on artificialteeth surfaces. In conclusion, our in vitro studies demonstrated that PBOR and CBOR are more effective against VAP pathogens compared to commercial mouth rinses and they can also inhibit biofilm formation.

Antibacterial hydrogels based on poly(sodium 2-acrylamido-2-methylpropane sulfonate) and gelatin and incorporating chlorhexidine gluconate (CHG) as a drug were fabricated. The work focused on the effects of varying the CHG concentration. The hydrogel containing 0.02% w/v of CHG was chosen as the drug-loaded hydrogel for comparison with the hydrogel with no drug. From the drug release results, it was found that only 2-5% CHG was released, indicating that the CHG strongly interacted with the hydrogel network. To confirm the antibacterial efficiency of the hydrogels, the shake-flask method and scanning electron microscopy were employed. The antibacterial activity of the drug-loaded hydrogels showed a 7-log reduction for S. aureus gram-positive and a 5-6-log reduction for E. coli gram-negative bacteria. In addition, an MTT assay was performed to evaluate their potential cytotoxicity and showed a percentage cell viability after 24 h of more than 70% which classified them as being non-cytotoxic. In conclusion, the hydrogels containing CHG are considered as one of the interesting candidates for potential biomedical use as antibacterial wound dressings. Further in vivo investigations are planned.

Propolis is proposed to possess antibacterial and anti-inflammatory properties, which can be used in endodontic applications. However, evidence on its efficacy in comparison to chlorhexidine against Enterococcus faecalis (E. faecalis) is controversial. The aim of the current study was to compare the antibacterial efficacy of Propolis and chlorhexidine as an intracanal medicament against E. faecalis in extracted human permanent teeth. The focused question was, “Does Propolis show better antibacterial efficacy than Chlorhexidine (CHX) as an intracanal medicament against E. faecalis in extracted human permanent teeth?”. Databases including PubMed/Medline, Scopus, EMBASE, ISI-Web of Science were searched from 1990 to August 2020 using different combinations of the following keywords: “Propolis”, “Intracanal medicament”, “E. faecalis”, “Antibacterial activity” and “Chlorhexidine”. Ten studies fulfilling inclusion criteria were considered for qualitative analysis, followed by quantitative...

Background: Currently, the most common therapy for periodontal diseases consists of professional scaling and root planing (SRP). However, it was found to be of limited efficacy especially in areas which are inaccessible to periodontal instrumentation. Therefore, treatment strategies using antimicrobials in conjunction with conventional therapy have evolved. Thus, the study was undertaken with an. Aim: To evaluate the efficacy of application of chlorhexidine gel and curcumin gel as an adjunct to SRP. Materials and Methods: The study was conducted on thirty chronic periodontitis patients who were divided into two groups as control and experimental groups using a split-mouth design. After SRP chlorhexidine gel was applied in control and curcumin gel in experimental groups. The plaque index, gingival index, sulcus bleeding index, probing pocket depth were recorded at baseline and subsequently after 1 month and 45 days. Results: The results revealed that both chlorhexidine gel and curcumin gel have an effect on mild to moderate periodontal pockets in chronic periodontitis patients, but greater reduction was observed in the experimental group than the control group. Conclusion: It can be concluded that both control and experimental gel can be used as an adjunct to SRP, but the curcumin gel was more effective than the chlorhexidine gel in the treatment of mild to moderate periodontal pockets with a significant reduction in the indice scores when compared to the baseline values.

Background With an annual estimated 276,000 neonatal deaths, Nigeria has the second highest of any country in the world. Global progress in accelerating neonatal deaths is hinged to scaled-up interventions in Nigeria. We used routine data of chlorhexidine digluconate 7.1% gel utilized by 36,404 newborns delivered by 36,370 mothers, to study lessons associated with atscale distribution in Sokoto State, North West Nigeria.

Objectives: The aim of this study was to evaluate the effectiveness of three different antiseptic mouthrinse solutions on the saliva samples obtained from the individuals, who had high caries activity rate. Methods: The efficacy of three antiseptic mouthrinses were evaluated in a study with healthy volunteers. The three antiseptic solutions used in this study were 0.1% octenidine dihydrochloride (Octenisept, Schülke&Mayr, UK), 0.12% chlorhexidine digluconate (Kloroben, Drogsan, Turkey) and an antimicrobial enzymatic rinse (Biotene, Laclede,Inc, USA). A total of 27 adult volunteer subjects were participated in the study. The subjects were stratified into three balanced group. Then the mouth rinses were used by each group according to the manufacturer's directions. The subjects were restricted for 60 minutes for food intake after using the prescribed mouthrinse. The saliva samples were collected from the volunteers at 1, 10 and 60 minutes after their usage in tubes. The tubes were kept in +4°C in a fridge till the evaluation. 10-3 and 10-5 dilutions were prepared for each solution and S. mutans were evaluated according to total number of colony forming unit (CFU) per ml. The dilutions were spreaded on the surface of Brucella agar plates for anaerobic incubation for 48 hours. The dilutions were 100, 10-3 and 10-5 of the solutions Kloroben, Biotene, Octenisept, and the time factor were 0, 1, 10 and 60 minutes. The statistical analyses were performed by Duncan and Bonferroni tests. Results: Octenisept was found to be more effective over S. mutans than the other mouthrinse solutions (P<.05). Conclusions: All mouthrinse solutions except Biotene were effective on oral microorganisms.

Background: Chlorhexidine digluconate (CHG) is used as a disinfectant. The emergence of pathogens resistant to the biocide raises health concern. Information on specific efflux mechanisms utilised by bacteria to confer reduced susceptibility to the biocide, may be used to develop ways of preventing the efflux of the biocide from nosocomial pathogens resulting in higher disinfection activity. The aim of the study was to evaluate the role of ATP-binding cassette transporters on the transport of CHG in bacteria. Methods: Clinical strains of Pseudomonas aeruginosa, Staphylococcus aureus and their respective laboratory strains ATCC 27853 and ATCC 9144 were used for susceptibility tests. The minimum inhibitory concentration (MIC) of CHG with or without an efflux pump inhibitor [reserpine or carbonyl cyanide m-chlorophenylhydrazone (CCCP)] was determined using the broth microdilution method. A spectrophotometric method to quantify the amount of chlorhexidine in a sample was developed, validated and used to quantify CHG within P. aeruginosa and S. aureus cells. Results: In the presence of reserpine, the MIC of CHG against the clinical strains of P. aeruginosa and S. aureus decreased from 6.3 to 3.2 µg/ml but showed no change against both ATCC isolates. The MIC of CHG in the presence of CCCP for both strains of P. aeruginosa remained unchanged but showed a reduction for both isolates of S. aureus. The suitability of the spectrophotometric method developed for quantifying the amount of CHG accumulated in microbial cells was validated and used successfully to quantify CHG accumulated within bacterial cells. Conclusion: The spectrophotometric determination of CHG within microbial cells may be used to quantify CHG in microbial cells. Only the clinical strain of P. aeruginosa showed significant efflux of CHG suggesting the participation of efflux transporters in the pumping out of CHG from this isolate. The use of efflux pump inhibitors together with the biocide may be explored to preventing the efflux of the biocide from P. aeruginosa resulting in order to increase disinfection activity.

Background: Studies regarding cleansing the area with antiseptic solutions prior to catheterization in premature infants are limited. Therefore, the present study aimed to evaluate and compare the effects of chlorhexidine 2% and iodopovidone-alcohol solutions on bacterial colonization associated with the peripheral venous catheterization in premature infants. Methods: This quasi-experimental study was conducted in 2016-2017 at a neonatal intensive care unit in Qazvin, Iran. Premature infants (N=106) were assigned to the two groups of “A” treated with chlorhexidine 2% or “B” cleaned with iodopovidone-alcohol 10%. Quantitative culture of the catheters was performed 48 hours after insertion. Results: Our findings showed that the frequency of positive catheter tips culture was 6.6% among all the samples (N=7). Out of the seven positive cultures, five (43.9%) belonged to the iodopovidone-alcohol group and two (3.7%) were from the chlorhexidine 2% group. Although a number of the positive ...

Significance and Impact of the Study: We measured the antichlamydial effects of various antiseptics. These antiseptics are being used for the treatment of bacterial vaginosis, but their effect on the bacterial vaginosis-related sexually transmitted infections, particularly the most frequent Chlamydia trachomatis (C. trachomatis) infections has not been investigated. We showed that povidone-iodine (Betadine) inhibited the chlamydial growth in concentrations that was not toxic to the epithelial cells. We concluded that due to its additional antichlamydial effect, povidone-iodine could be a preferable antiseptic in bacterial vaginosis treatment.

Quercetin is an anti-inflammatory substance that possesses strong anti-inflammatory capacities through reduction of proinflammatory cytokines. Interleukin-6 is a proinflammatory cytokine produced locally in inflammatory tissue after lipopolysaccharides and other cytokines activation. The research analyzed effect of 2% quercetin gel subgingival application after scaling and root planing on IL-6 concentration of chronic periodontitis patients. It used 2% quercetin gel after scaling and root planing and 0,2% chlorhexidine gel as control. Sample was divided into 3 groups, quercetin gel group, control group (chlorhexidine gel and without gel). Gingival crevicular fluid was taken before and after treatments in each group then IL-6 examination was performed. This research used pretest-posttest control group design. There was significant difference (p

Introduction/Objectives. Enterococcus faecalis has been implicated in infections of treated root canals. Current irrigants and intracanal medicaments cannot eliminate E. faecalis completely from the root canal. Silver diamine fluoride (SDF) prevents caries by promoting remineralization and exerting an antibacterial effect. Studies suggest that SDF may possess antibacterial properties against E. faecalis. The purpose of this review is to systematically and critically analyze the literature, focusing on the use of SDF as an intracanal medicament or irrigant, when compared to other antibacterial agents. Data/Sources. The focused question was "Is the antibacterial effect of SDF against E. faecalis better than other intracanal medicaments and irrigants?" Using the keywords ((silver diamine fluoride) AND (Enterococcus faecalis)) AND ((sodium hypochlorite) OR (NaOCl) OR (chlorhexidine) OR (calcium hydroxide) OR (Ca(OH) 2)), an electronic search was conducted on the following databases: PubMed/MEDLINE, ISI Web of Science, Scopus, EMBASE, and Google Scholar. The clinical trial registers ClinicalTrials.gov and CONTROL were also searched using the same keywords. General characteristics and outcomes were extracted, and quality of the studies was assessed using the Preferred Reporting Items for Laboratory studies in Endodontology (PRILE) guidelines. Study Selection. Six articles (five in vitro studies and one ex vivo study) were included in this systematic review. In the majority of the studies, SDF had equal or better antibacterial efficacy against E. faecalis compared to calcium hydroxide, sodium hypochlorite, and chlorhexidine. However, the majority of the studies did not fulfill several items in the PRILE criteria and had numerous sources of bias. Conclusions. Within the limitations of the systematic review and the studies reviewed, SDF may be effective against E. faecalis and therefore could be used as an intracanal medicament and/or irrigant to prevent reinfections of the root canals and improve the outcomes of endodontic treatment. However, animal and clinical studies

Hemodialysis (HD) catheter‐related infection (CRI) and septicemia contribute to adverse outcomes. The impact of seasonality and prophylactic dialysis practices during high‐risk periods remain unexplored. This multicenter study analyzed DOPPS data from 12,122 HD patients (from 442 facilities) to determine the association between seasonally related climatic variables and CRI and septicemia. Climatic variables were determined by linkage to National Climatic Data Center of National Oceanic and Atmospheric Administration data. Catheter care protocols were examined to determine if they could mitigate infection risk during high‐risk seasons. Survival models were used to estimate the adjusted hazard ratio (AHR) of septicemia by season and by facility catheter dressing protocol. The overall catheter‐related septicemia rate was 0.47 per 1000 catheter days. It varied by season, with an AHR for summer of 1.46 (95% CI: 1.19–1.80) compared with winter. Septicemia was associated with temperature (...

Background: Periodontal disease is a highly prevalent illness that affects many dogs, reaching up to 85 % prevalence in individuals over the age of 4 years. Currently the drug of choice for combating the formation of dental plaque in these animals, the etiologic agent of the disease, is chlorhexidine, which has several side effects reported. Thus, surveys are conducted throughout the world in order to identify potential substitutes for antimicrobial therapy and prevention of periodontal disease. The objective of the work was to evaluate the antimicrobial activity of β-caryophyllene against bacteria from dog's dental plaque in vitro and in vivo. The minimum inhibitory concentration was evaluated by agar microdilution assay, the induction or inhibition of bacterial adherence by sub-inhibitory concentrations in 96-well plates, and reduction of dental plaque formation in mongrel dogs subjected to topical solution with β-caryophyllene for 15 days. Results: Results showed minimum inhibitory concentrations above 100 mg/mL for 25 % of the isolates, 100 mg/mL for 3 %, 50 mg/mL for 25 %, 25 mg/mL for 12 %, 12.5 mg/mL for 19 % and 6.25 mg/mL for 16 %. Bacterial adherences of three Enterococcus sp., one Streptococcus sp., one Haemophilus sp., one Aerococcus sp., one Bacillus sp. and one Lactococcus sp. isolates were inhibited by subinhibitory concentration. One Lactococcus sp., one Bacillus sp. and one Streptococcus sp. were stimulated to adhere by concentrations of 0.19, 1.56 and 0.78 mg/mL, respectively. In vivo assay showed reduction in dental plaque formation by β-caryophyllene, with final plaque coverage of 23.3 ± 2.6 % of the total area of the teeth, with significant difference compared with chlorhexidine group (37.5 ± 3.7 %-p < 0.05) and negative control group (65.5 ± 2.5 %-p < 0.001). Conclusions: The results showed that β-caryophyllene has antimicrobial activity against the proliferation of dog's dental plaque-forming bacteria representing a suitable alternative to the use of chlorhexidine in prophylaxis and treatment of periodontal disease of dogs.

Introduction: Biofilms are recognized as a significant deterrent to wound healing and to the management of exposed or infected surgical implants. Biofilms can be disrupted by a variety of enzymatic and mechanical interventions. This experiment was designed to determine whether direct-contact low-frequency ultrasound has the ability to clear biofilms and what then happens to the released bacteria. Methods:Staphylococcus epidermidis biofilm was grown on the surfaces of metallic discs composed of titanium and stainless steel, comparable with the alloys used in surgical implants. The discs were treated with a control of irrigation and no ultrasound, followed by the ultrasound for a 10 second of exposure at a mid-level power setting. The irrigation materials used was either normal saline or hypochlorous acid. The effluent was cultured to determine colony-forming units, and the discs were stained with crystal violet to determine whether there was a residual biofilm. Results: The biofilm was cleared completely from all discs when treated with direct-contact low-frequency ultrasound. However, the released bacteria were viable and could be cultured from the effluent when saline was used as the irrigation medium. When hypochlorous acid was used as the irrigation medium, there was complete killing of all planktonic bacteria. Conclusion: Direct-contact low-frequency ultrasound is effective when used to clear biofilms from metallic implant materials. By using hypochlorous acid as the irrigant during treatment, all of the bacteria released from the biofilm were killed as well. The implications for clinical application are important and need to be independently studied.

Introduction: The study aimed to assess the effect of different concentrations of sodium hypochlorite and calcium hypochlorite on micro hardness of root canal dentin. Methodology: The seventy five root halves were prepared by longitudinal splitting of seventy five extracted mandibular premolars and embedded in autopolymerizing acrylic resin, leaving the dentin surface exposed After polishing, the groups were then divided into five groups of 15 samples each through random sampling the microhardness values of the untreated dentin surfaces were recorded by using Vickers tester at the mid-root level. Then samples were surface treated for five minutes with five ml of one of the following irrigants Saline (control group), 2.5% NaOCl solution, 5% NaOCl solution, 5% CaOCl2 solution, 10% CaOCl2 solution. After surface treatment,dentin microhardness values were recorded at close proximity to the initial indentation areas. Experimental data were statistically analyzed by using one way ANOVA te...

Introduction: Chlorhexidine 4% gel is specifically formulated for umbilical cord care and is safe and effective for reducing bacterial colonization on the skin and umbilical stump of the newborn. 7.1% chlorhexidine digluconate delivering 4% chlorhexidine was added to the 2013 World Health Organization (WHO) List of Essential Medicines for Children, specifically for umbilical cord care. Chlorhexidine can induce allergic contact dermatitis, immediate type hypersensitivity reaction, urticaria, photosensitivity, chemical burns and maculopapular erythema. Method: Hospital based descriptive and observational study was carried out in Paropakar Maternity and Women`s Hospital, Thapathali. The study was carried out for 5 months from September 2017 to February 2018. Total of 300 newborns whose umbilical cord was about to be removed were included in the study. Chlorhexidine gluconate gel was applied immediately after the removal of umbilical cord for the prophylactic treatment of umbilical cord...

Bovine mastitis due to Prototheca zopfii leads to reduced milk production and is difficult to cure. Therefore, prevention is the best approach and this is best achieved through the use of effective disinfectants. The aim of this study was to evaluate the in vitro algaecide efficacy of conventional disinfectants against strains of P. zopfii genotype 1 and 2. The minimal algaecide concentration (MAC) of alkyldiaminoethylglycine hydrochloride, chlorhexidine, dioxide chlorine, povidone iodine and sodium hypochlorous acid against 10 isolates and the type strain (SAG2063 T) of P. zopfii genotype 1 as well as 10 isolates and the type strain (SAG2021 T) of P. zopfii genotype 2 were examined using the micro dilution method. This in vitro study indicated that alkyldiaminoethylglycine hydrochloride, chlorhexidine, povidone iodine and sodium hypochlorous acid, but not dioxide chlorine, are effective against both genotypes of P. zopfii.

Bovine mastitis due to Prototheca zopfii leads to reduced milk production and is difficult to cure. Therefore, prevention is the best approach and this is best achieved through the use of effective disinfectants. The aim of this study was to evaluate the in vitro algaecide efficacy of conventional disinfectants against strains of P. zopfii genotype 1 and 2. The minimal algaecide concentration (MAC) of alkyldiaminoethylglycine hydrochloride, chlorhexidine, dioxide chlorine, povidone iodine and sodium hypochlorous acid against 10 isolates and the type strain (SAG2063 T) of P. zopfii genotype 1 as well as 10 isolates and the type strain (SAG2021 T) of P. zopfii genotype 2 were examined using the micro dilution method. This in vitro study indicated that alkyldiaminoethylglycine hydrochloride, chlorhexidine, povidone iodine and sodium hypochlorous acid, but not dioxide chlorine, are effective against both genotypes of P. zopfii.

Bovine mastitis due to Prototheca zopfii leads to reduced milk production and is difficult to cure. Therefore, prevention is the best approach and this is best achieved through the use of effective disinfectants. The aim of this study was to evaluate the in vitro algaecide efficacy of conventional disinfectants against strains of P. zopfii genotype 1 and 2. The minimal algaecide concentration (MAC) of alkyldiaminoethylglycine hydrochloride, chlorhexidine, dioxide chlorine, povidone iodine and sodium hypochlorous acid against 10 isolates and the type strain (SAG2063 T) of P. zopfii genotype 1 as well as 10 isolates and the type strain (SAG2021 T) of P. zopfii genotype 2 were examined using the micro dilution method. This in vitro study indicated that alkyldiaminoethylglycine hydrochloride, chlorhexidine, povidone iodine and sodium hypochlorous acid, but not dioxide chlorine, are effective against both genotypes of P. zopfii.

A placa bacteriana é fator primário na formação de gengivite, cálculo dentário, halitose e doença periodontal. Objetivou-se avaliar a quantidade de placa bacteriana dental removida pela escova dental e dedeira. Foram utilizados 60 cães machos e fêmeas de diferentes raças, idade e peso, divididos em dois grupos. O índice Logan & Boyce foi utilizados para quantificar a placa bacteriana antes e após a escovação. Observou-se diferença estatística (p&lt;0,05) na remoção da placa bacteriana antes e após escovação. Não houve diferença estatística (p&gt;0,05) entre a utilização da escova dental e a dedeira.

This study aimed to evaluate in vitro the antimicrobial effect of a bioadhesive chitosanbased oral membrane with chlorhexidine for local treatment of infections in the oral tissues. Five oral membranes of different compositions were tested: 5% chitosan (G1); 5% chitosan ± 0.2% chlorhexidine (G2), 5% chitosan ± 0.6% chlorhexidine (G3), 5% chitosan ± 1.0% chlorhexidine (G4), and 5% chitosan ± 2.0% chlorhexidine (G5). Also, five gel types were tested according to the following compositions: 5% chitosan gel (G6), 0.2% chlorhexidine gel (G7), 2.0% chlorhexidine gel (G8), 5% chitosan gel ± 0.2% chlorhexidine gel (G9), and 5% chitosan gel ± 2.0% chlorhexidine gel (G10). The antimicrobial action of the samples was tested against Candida albicans and Streptococcus mutans through antibiogram by measuring the inhibition halos. Data were statistically analyzed by Kruskal-Wallis and one-way ANOVA followed by Tukey test (p<0.05). The 2.0% chlorhexidine membrane (G5) and the disks containing 2.0% chlorhexidine gel (G8) showed the greatest inhibition halos for both microorganisms, with statistically significant difference when compared to others tested groups (p=0.008) only for Candida albicans inhibitions results. All the other formulations of membranes and gels showed inhibition halos, but without statistically significant difference. The bioadhesive chitosan-based oral membrane with 2% chlorhexidine and 2% chlorhexidine gel were the most effective in inhibiting the tested microorganisms.

This study aimed to evaluate in vitro the antimicrobial effect of a bioadhesive chitosan-based oral membrane with chlorhexidine for local treatment of infections in the oral tissues. Five oral membranes of different compositions were tested: 5% chitosan (G1); 5% chitosan ± 0.2% chlorhexidine (G2), 5% chitosan ± 0.6% chlorhexidine (G3), 5% chitosan ± 1.0% chlorhexidine (G4), and 5% chitosan ± 2.0% chlorhexidine (G5). Also, five gel types were tested according to the following compositions: 5% chitosan gel (G6), 0.2% chlorhexidine gel (G7), 2.0% chlorhexidine gel (G8), 5% chitosan gel ± 0.2% chlorhexidine gel (G9), and 5% chitosan gel ± 2.0% chlorhexidine gel (G10). The antimicrobial action of the samples was tested against Candida albicans and Streptococcus mutans through antibiogram by measuring the inhibition halos. Data were statistically analyzed by Kruskal-Wallis and one-way ANOVA followed by Tukey test (p&lt;0.05). The 2.0% chlorhexidine membrane (G5) and the disks containing 2...

Background: Immediate drug hypersensitivity reactions are an increasing public health issue and a frequent cause of lifethreatening anaphylaxis. Conventional confirmatory testing include skin tests and, for a few drugs, quantification of drug-specific immunoglobulin E (IgE) antibodies. However, none of these tests are absolutely predictive for the clinical outcome, and can yield false-negative and false-positive results. We performed a proof-of-concept study to assess whether a mast cell activation test could improve diagnosis of IgE-mediated chlorhexidine hypersensitivity, a common cause of perioperative anaphylaxis. Methods: Human mast cells were generated from CD34 þ progenitor cells and sensitised with patients' sera to become IgEþ human mast cells (dMC IgEþ), and then incubated with chlorhexidine to assess degranulation. We compared the diagnostic performance of this mast cell activation test with serum from patients with and without positive skin test and basophil activation test to chlorhexidine. Results: In dMC sensitised with sera from patients with a positive skin test and basophil activation test to chlorhexidine showed drug-specific and concentration-dependent degranulation upon stimulation with chlorhexidine, determined by surface upregulation of the degranulation marker CD63. In contrast, dMC sensitised with sera from patients with a negative skin test and basophil activation test to chlorhexidine were unresponsive in the mast cell activation test. Conclusions: Our study suggests that the mast cell activation test can be used to diagnose IgE/FcεRI-dependent immediate drug hypersensitivity reactions. It also shows potential to assess the clinical relevance of drug-specific IgE antibodies in their ability to elicit mast cell degranulation, and therefore discriminate between allergy and sensitisation. Extended studies are required to verify whether this technique can be used in other causes of perioperative anaphylaxis.