Histoplasmosis

Histoplasma capsulatum was isolated from gut, lung, liver, and spleen of 17 of 208 captured bats belonging to 6 different genera and species. Three of the 17 infected bats were from the State of Guerrero and 14 were from the State of Morelos. All were adult bats: 6 males (1 Pteronotus parnellii, 2 Natalus stramineus, 2 Artibeus hirsutus, and 1 Leptonycteris nivalis) and 11 females (1 Myotis californicus, 1 Mormoops megalophylla, 8 A. hirsutus, and 1 L. nivalis). High rates of bat infection with H. capsulatum were found in the monitored sites of the State of Morelos. Histoplasma infection of N. stramineus, A. hirsutus, and L. nivalis should be considered as the first records in the world. The fungus isolated from infected bats was identified by its typical mycelial-phase morphology and by its yeast-phase conversion. Exoantigen production confirmed the fungal identification by the presence of specific precipitation lines in double immunodiffusion assays using human immune serum. Histopathologic studies showed intracellular yeast-like cells compatible with H. capsulatum yeast-phase in tissues of several bats, especially in pulmonary (intra-alveolar and septal) macrophages, with none or minimal tissue reaction. In contrast to past reports, present data support a high risk of bat infection with H. capsulatum in Mexican cave environments.

A case of disseminated histoplasmosis in a 56-year-old apparently healthy male without any history of travel to endemic zone is described. The patient presented with fever with cough, respiratory distress and disorientation. Physical findings include fever, shortness of breath, reduced level of consciousness and hypotension. Diagnosis was confirmed by presence of Histoplasma capsulatum in bone marrow aspirate. This report illustrates the importance of recognizing the possibility of histoplasmosis in Bangladesh where mimickers of histoplasmosis like pulmonary tuberculosis and visceral leishmaniasis are extremely common.

Histoplasmosis, caused by the dimorphic fungus Histoplasma capsulatum, is endemic in many regions of the Americas, Asia and Africa. It has a wide spectrum of clinical manifestations, from asymptomatic infection to severe disseminated disease. A retrospective study was carried ...

Histoplasmosis is an endemic and systemic mycosis, caused by the dimorphic fungus Histoplasma capsulatum var capsulatum. Disseminated disease in immunocompromised patients generally results from the reactivation of latent foci after a prolonged period of asymptomatic infection. We report a case of laryngeal histoplasmosis as the unique clinical manifestation of a progressive form of the disease in a patient with advanced HIV/AIDS disease. Histopathological analysis of laryngeal biopsy smears revealed granulomas containing Histoplasma-like organisms. Treatment with amphotericin B followed by itraconazole resulted in complete remission of laryngeal lesions. To our knowledge, this is the third case report of laryngeal histoplasmosis in a patient with AIDS.

ABSTRACT Isolated laryngeal histoplasmosis is a very rare entity. It has variable clinical presentations that might
mimic both benign and malignant lesions, and is usually associated with pulmonary and other disseminated forms
of histoplasmosis. Herein, we report a case of primary laryngeal histoplasmosis without the involvement of other
systems in a 70-year-old Chinese man, who previously worked as a miner. He presented with a history of hoarseness
for two months, with no other associated symptoms. Direct laryngoscopy revealed irregularity of the posterior onethird
of both vocal folds. Histopathological examination revealed the presence of Histoplasma capsulatum on periodic
acid-Schiff and Grocott’s methenamine silver staining. The lesion resolved after one month of oral itraconazole
treatment. However, the patient had to complete six months of antifungal treatment to prevent recurrence.

Histoplasmosis, caused by Histoplasma capsulatum, endemic in Venezuela, is the most frequent AIDS defining disease. It is associated with significant morbidity and mortality in these patients. The aim of this study was to review the demographic data, clinical features, diagnostic methods, treatment and follow-up, of patients with diagnosis of AIDS and histoplasmosis, evaluated at the Medical Mycology Department, Instituto de Medicina Tropical, Universidad Central de Venezuela, from 1994 to 2013. We collected demographic, epidemiologic, and clinical data from each case. Viral load and CD4+ counts were recorded when available. The diagnosis of histoplasmosis was performed by standard methods. Treatment and outcome was also considered. We found a high proportion of co-infection of HIV/AIDS and histoplasmosis, 39.42%, quite similar to other reports. The majority of patients, 149 (68.34%), came from urban environments. 155 had CD4+ counts below 150 cells/ mL. Out of these, 16 had previous ART. Adherence could not be established. In 79.8%, histoplasmosis was the AIDS-defining disease. All patients presented with a progressive disseminated disease. It is noteworthy that 9 (4.13%) patients were co-infected with Paracoccidioides brasiliensis. Finally, we believe that in our country, and what is more, in any other country in which histoplasmosis is endemic, it is necessary that clinicians consider the diagnosis of this disease, when they evaluate AIDS patients with fever, pulmonary, skin/mucosal, CNS or gastrointestinal manifestations and laboratory alterations such as cytopenias or liver enzyme abnormality. Physicians must be familiar with the uses and limitations of the current diagnostic tests available for fungal diseases.

Adrenal histoplasmosis is an uncommon mycotic disease typically caused by Histoplasma capsulatum. The objective was to determine the clinicopathological findings in adrenal histoplasmosis. Pathological records were searched from the database at the Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University from 1993 to 2008 for cases of adrenal histoplasmosis. The keywords were "histoplasmosis" and "adrenal gland". Adrenal histoplasmosis was diagnosed by histopathology and Gomori-Grocott methenamine silver staining. Histoplasma capsulatum was confirmed by tissue culture and/or serology. The authors report seven cases of adrenal histoplasmosis in immunocompetent patients. The mean age at diagnosis was 67 years. All patients presented as chronic fatigue syndrome. The onset of symptoms ranged from one to three months. Addison's disease was found in adrenal histoplasmosis in one case (14.3%). The computed tomography revealed adrenal nod...

High sensitivity and specificity of molecular biology techniques have proven usefulness for the detection, identification and typing of different pathogens. The ITS (Internal Transcribed Spacer) regions of the ribosomal DNA are highly conserved non-coding regions, and have been widely used in different studies including the determination of the genetic diversity of human fungal pathogens. This article wants to contribute to the understanding of the intra-and interspecific genetic diversity of isolates of the Histoplasma capsulatum and Sporothrix schenckii species complexes by an analysis of the available sequences of the ITS regions from different sequence databases. ITS1-5.8S-ITS2 sequences of each fungus, either deposited in GenBank, or from our research groups (registered in the Fungi Barcode of Life Database), were analyzed using the maximum likelihood (ML) method. ML analysis of the ITS sequences discriminated isolates from distant geographic origins and particular wild hosts, depending on the fungal species analyzed.

Systemic histoplasmosis has various clinical presentations and is of especial concern in immunocompromised patients. A high index of suspicion is required for its diagnosis. A total of 38 cases had been reported from India up to 1996. The most frequent occurrence of cases was around Calcutta in eastern India where the previous case was detected 20 years earlier. However, we have diagnosed 5 cases in the past 2 years from eastern India which are reported here. These cases may indicate under-diagnosis and under-reporting of histoplasmosis in India. All 5 patients had disseminated disease with multisystem involvement including 2 with bilateral adrenal enlargement. Two were diabetic and only 1 patient was infected with HIV.

A 5-year-old Holsteiner gelding from Germany was presented 2 months after a whitish discoloration of the left cornea was observed. Cytologic examination revealed intra-and extracellular globular structures, up to 4 µ m in size, consisting of a central spherical deeply basophilic body surrounded by an unstained halo. The structures were morphologically consistent with Histoplasma spp. Infection with Histoplasma organisms is not endemic in Europe. Topical use of fluconazole was successful in eliminating Histoplasma organisms within 10 days of initiation of treatment.

Adrenal histoplasmosis is an uncommon mycotic disease typically caused by Histoplasma capsulatum. The objective was to determine the clinicopathological findings in adrenal histoplasmosis. Pathological records were searched from the database at the Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University from 1993 to 2008 for cases of adrenal histoplasmosis. The keywords were "histoplasmosis" and "adrenal gland". Adrenal histoplasmosis was diagnosed by histopathology and Gomori-Grocott methenamine silver staining. Histoplasma capsulatum was confirmed by tissue culture and/or serology. The authors report seven cases of adrenal histoplasmosis in immunocompetent patients. The mean age at diagnosis was 67 years. All patients presented as chronic fatigue syndrome. The onset of symptoms ranged from one to three months. Addison's disease was found in adrenal histoplasmosis in one case (14.3%). The computed tomography revealed adrenal nod...

S e denomina infección por el virus de la inmunodeficiencia humana adquirida (VIH) al proceso patológico que se inicia a partir del ingreso del virus al cuerpo hasta el desarrollo de síntomas. Una vez que el virus ha invadido las células CD 4(+), el proceso es irreversible y progresa hacia el deterioro gradual y crónico del sistema inmune, presentando en algún momento de la enfermedad complicaciones infecciosas o tumorales que pueden comprometer la vida del paciente.

The bioactive lipid mediator leukotriene B 4 (LTB 4 ) greatly enhances phagocyte antimicrobial functions against a myriad of pathogens. In murine histoplasmosis, inhibition of the LT-generating enzyme 5-lypoxigenase (5-LO) increases the susceptibility of the host to infection. In this study, we investigated whether murine resistance or susceptibility to Histoplasma capsulatum infection is associated with leukotriene production and an enhancement of in vivo and/or in vitro antimicrobial effector function. We show that susceptible C57BL/6 mice exhibit a higher fungal burden in the lung and spleen, increased mortality, lower expression levels of 5-LO and leukotriene B 4 receptor 1 (BLT 1 ) and decreased LTB 4 production compared to the resistant 129/Sv mice. Moreover, we demonstrate that endogenous and exogenous LTs are required for the optimal phagocytosis of H. capsulatum by macrophages from both murine strains, although C57BL/6 macrophages are more sensitive to the effects of LTB 4 than 129/Sv macrophages. Therefore, our results provide novel evidence that LTB 4 production and BLT 1 signaling are required for a histoplasmosis-resistant phenotype.

Summary. In this study 19 donkeys suffering from face excoriations below the medial canthas and lesions in the lacrymal apparatus were subjected to clinical radiological and microbiological investigations. Also histopathological examination of biopsy materials from ocular lesions were made. Eleven out of 19 donkeys (57.9%) showed specific lesions in the lacrymal apparatus. Mycological examination revealed the isolation of Histoplasma cells from 10 out of 19 examined cases. The isolated Histoplasma culture, although not completely identical to H. farciminosum, was more related to this than to other Histoplasma species. Histopathological examination revealed the presence of marked tissue infiltration by lymphocytes, monocytes and macrophages. Also the fungal organism appeared as double-contoured yeast cells lying within macrophages and giant cells.Zusammenfassung. In dieser Studie wurden 19 Esel mit Hautabschürfungen am Vorderkopf unter den medialen Augenwinkeln und Läsionen im Trä-nenapparat klinisch, radiologisch und mikrobiolo-gisch untersucht. Auch histopathologische Unter-suchungen wurden durchgeführt. 11 der 19 unter-suchten Esel (57,9 %) zeigten spezifische Läsionen im Tränenapparat. Die mykologische Untersu-chung führte zur Isolierung von Histoplasma-Zellen bei 10 der 19 untersuchten Tiere. Die isolierte Hi-stoplasma-Kultur war zwar nicht vollständig iden-tisch mit H. farciminosum, ähnelte dieser jedoch mehr als jeder anderen Histoplasma-Art. Die histopathologische Untersuchung zeigte eine deutliche Gewebsinfiltration mit Lymphozyten, Monozyten und Makrophagen. Die Pilzzellen erschienen auch als doppelt konturierte Hefezellen, intrazellulär in Makrophagen und Riesenzellen gelegen.

Coinfection with tuberculosis in some countries occurs in 8-15% of human immunodeficiency virus (HIV) -infected patients who have histoplasmosis. This coinfection interferes with prompt diagnosis, and treatment is difficult because of drug interactions. We retrospectively reviewed the cases of 14 HIV-infected patients who had concomitant tuberculosis and histoplasmosis. The most frequent clinical manifestations were weight loss (85.7%), asthenia (78.5%), and fever (64.2%). The diagnosis of histoplasmosis was made primarily by histopathology (71.4%), and the diagnosis of tuberculosis was made by means of direct microscopic examination (71.4%). Death occurred in two patients, and relapse of both infections occurred in one patient. Moxifloxacin was substituted for rifampicin in six patients, with good outcomes noted for both infections. The clinical presentation does not readily identify acquired immunodeficiency syndrome (AIDS) patients who have tuberculosis and histoplasmosis. The use of a fluoroquinolone as an alternative agent in place of rifampicin for tuberculosis allows effective therapy with itraconazole for histoplasmosis.

Immunocytoadherence was investigated as a method of detecting active histoplasmosis in two groups of infected New Zealand white rabbits. Yeast-phase Histoplasma capsulatum was given intravenously to one group and intratracheally to the other. There was a striking correlation between the clinical condition of the animals and the number of rosettes seen. This number increased as the infection progressed and decreased as it regressed. The immunocytoadherence technique might be of value in detecting active histoplasmosis, and investigation in humans is warranted.

Three isolates of Histoplasma capsulatum were identified from mice lung, liver, and spleen inoculated with soil samples of the X hotelÕs ornamental potted plants that had been fertilized with organic material known as compost. The presence of H. capsulatum in the original compost was detected using the dot-enzyme-linked immunosorbent assay. Nested-PCR, using a specific protein Hcp100 coding gene sequence, confirmed the fungal identification associated with an unusual histoplasmosis outbreak in Acapulco. Although, diversity between the H. capsulatum isolate from the hotel and some clinical isolates from Guerrero (positive controls) was observed using random amplification of polymorphic DNA based-PCR, sequence analyses of H-anti and ole fragment genes revealed a high homology (92-99%) between them.

Background: The purpose of this study was to determine the association of serum lactate dehydrogenase (LDH) levels with certain opportunistic infection and to determine an association between LDH levels and CD4+ lymphocyte counts. Methods: We studied 352 patients retrospectively with HIV infection and one of the following infections: histoplasmosis; toxoplasmosis; tuberculosis (pulmonary and disseminated); bacterial pneumonia; Pneurnocystis carinii pneumonia. Demographic and clinical data were obtained from the Adult Spectrum of Diseases (ASD) database in New Orleans. Bivariate and multivariate analysis were used to determine the association between LDH levels and opportunistic infections and CD4+ lymphocyte counts.

Protection against the pathogenic fungus Histoplasma capsulatum requires Th1 cytokines. Since interleukin-4 (IL-4) can inhibit both Th1 cytokine production and activity, we examined the effects of overproduction of IL-4 in the lung on the course of pulmonary histoplasmosis. IL-4 lung transgenic mice manifested a higher fungal burden in their lungs, but not spleens, compared to wild-type infected controls. Despite the higher burden, the transgenic animals were ultimately capable of controlling infection. The adverse effects of IL-4 on H. capsulatum elimination were not observed during the early phase of infection (days 1 to 3) but were maximal at day 7 postinfection, prior to the induction of cell-mediated immunity. Analysis of total body and lung cytokine levels revealed that gamma interferon and tumor necrosis factor alpha production were not inhibited in the presence of excess IL-4. Our results with transgenic mice were supported by additional in vivo studies in which allergen induction of pulmonary IL-4 was associated with delayed clearance of H. capsulatum yeast and increased fungal burden. These findings demonstrate that excess production of endogenous IL-4 modulates protective immunity to H. capsulatum by delaying clearance of the organism but does not prevent the generation of a Th1 response that ultimately controls infection.

We identified the incidence and primary clinical characteristics of histoplasmosis in patients with acquired immunodeficiency syndrome (AIDS) in our hospital. Disseminated histoplasmosis is a common and severe disease among patients with AIDS in Panama and should be suspected for patients with a CD4 cell count of !100 cells/mL, fever, respiratory symptoms, weight loss, and diarrhea.

An ELISA was developed and evaluated as a method for detecting antibodies against glycosylated and deglycosylated histoplasmin (HMIN). Sera from patients with histoplasmosis, paracoccidioidomycosis, sporotrichosis, coccidioidomycosis, aspergillosis, cryptococcosis and healthy donors were tested by ELISA against purified, deglycosylated histoplasmin (ptHMIN) and compared with purified, native (i.e. glycosylated) histoplasmin (pHMIN). Although cross-reactivity was not abolished when ptHMIN was used in the test, it was reduced (pHMIN ELISA 93 % versus ptHMIN ELISA 96 %). However, there were statistically significant differences between the sensitivities of these two methods for the detection of antibodies (pHMIN ELISA 57 % versus ptHMIN ELISA 92 %; P , 0 . 001) and between the efficiency of the methods (pHMIN ELISA 83 % versus ptHMIN ELISA 95 %; P , 0 . 001). These parameters compare better than previously published data relating to the use of treated HMIN in diagnostic ELISAs. Some of the reactivities of serum samples were compared by immunoblotting using deglycosylated HMIN and by immunodiffusion using the crude antigen. The results demonstrated that cross-reactions with heterologous sera in both ELISAs could also be observed in immunoblotting and arose from shared protein epitopes. These data suggest that ELISA using deglycosylated HMIN is a very sensitive diagnostic method and, by using commercially available antigen, it can be easily standardized and performed faster than previous Western blot-based tests using the same antigen. It provides a useful adjunct to existing methods of diagnosis that could be applied even in situations where laboratory facilities were relatively limited.

Abstract An outbreak of acute histoplasmosis occurred among 42 people who gathered for two days in May 1977 to cut and clear a fallen oak tree near Nashville (Williamson County), Tennessee. Thirty-two (76 per cent) of the participants had serologic evidence of infection; ...