Identification of the infectious source of an unusual outbreak of histoplasmosis, in a hotel in Acapulco, state of Guerrero, Mexico

Three isolates of Histoplasma capsulatum were identified from mice lung, liver, and spleen inoculated with soil samples of the X hotel's 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.     

Molecular typing of Histoplasma capsulatum isolated from infected bats, captured in Mexico

The present paper represents data on the genetic polymorphism of 13 Histoplasma capsulatum isolates recovered from infected bats randomly captured in the Mexican states of Morelos, Puebla, and Oaxaca. The polymorphic DNA patterns were analyzed by two-primer RAPD-PCR (random amplified polymorphic DNA-polymerase chain reaction) method. To amplify the fungal genome by PCR, the following primer arrangements were used: 5'-AACGCGCAAC-3' and 5'-AAGAGCCCGT-3'; 5'-AACGCGCAAC-3' and 5'-GTTTCCGCCC-3'; or 5'-AACGCGCAAC-3' and 5'-GCGATCCCCA-3'. A common polymorphic DNA pattern of H. capsulatum was revealed in different assays. This pattern is shared by 7 H. capsulatum isolates recovered from different specimens of nonmigratory bats (Artibeus hirsutus) captured in a cave in Morelos, by 5 isolates recovered from infected migratory bats (Leptonycteris nivalis) captured in Morelos and Puebla, and by 1 isolate from another migratory bat (L. curasoae) captured in Oaxaca. This polymorphic DNA pattern of H. capsulatum could represent fungal markers for the geographic areas studied, and considering its distribution in three different states of the Mexican Republic, the role of bats as responsible for H. capsulatum spreading in nature, in relation to their movements and migrations besides their shelter habits, is suggested. Analyses of DNA patterns of H. capsulatum isolated from infected bats, from clinical cases, and from blackbird excreta, have shown a major relatedness between bats and clinical isolates, in contrast to those isolates from bird excreta.     

Disseminated histoplasmosis with hemophagocytic syndrome in a patient with AIDS: description of one case and review of the Spanish literature

We report a case of disseminated histoplasmosis in a 33-year old Ecuadorian patient with AIDS and a CD4 lymphocyte count of 39 cells/microl. He presented with prolonged fever and cough, was diagnosed with hemophagocytic syndrome and multiple organ failure and died 18 days after admission. Histoplasma capsulatum was isolated post-mortem from bone marrow biopsy and blood culture. In a literature review we found 22 published cases of disseminated histoplasmosis in patients with AIDS in Spain since 1988. All but two were men under 50 years old. Nineteen had been born or had lived in endemic areas. The diagnosis of histoplasmosis was established by culture of bone marrow biopsy in 10 cases. Itraconazole was introduced as a second drug after amphotericin B in ten of the thirteen patients who survived.     

Production and standardization of Paracoccidioides brasiliensis, Histoplasma capsulatum and Aspergillus fumigatus antigens to be used in immunodiagnosis. Comparison between immunodiffusion and immunoelectrophoresis

Soluble antigens (Ag) from Paracoccidioides brasiliensis, Histoplasma capsulatum and Aspergillus fumigatus were prepared and standardized by double immunodiffusion (DID) and immunoelectroosmophoresis (IEOP). No difference in sensitivity was observed between the two techniques; 100% of standard patient sera were positive with P. brasiliensis and A. fumigatus Ag and 83.3% were positive with H. capsulatum Ag. The specificity of the tests was verified testing 96 sera from patients with paracoccidioidomycosis, histoplasmosis, systemic candidiasis, sporotrichosis, tuberculosis, lung cancer, visceral or cutaneous leishmaniasis and 18 sera from healthy individuals. All the three antigens were 100% specific with the DID (using the identification pattern indicated by the confluence of test serum with standard serum precipitin lines as a positive criterium). However in the IEOP, the specificity varied with each Ag. Positive reactions with P. brasiliensis Ag were observed in 16.7% of histoplasmosis sera and in 10% of cutaneous leishmaniasis sera. On the other hand 31.8% of paracoccidioidomycosis and 10% of cutaneous leishmaniasis sera reacted with H. capsulatum Ag. The high sensitivity and specificity of the DID test, its easy reproducibility and low cost, led us to consider it highly appropriate as a routine procedure for the screening of patients with respiratory infections.     

HLA Typing of Patients with 21-Hydroxylase Deficiency in Iranian Children with Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia (CAH) is a group of potentially life-threatening disorders, most often caused by deficiency of steroid 21-hydroxylase. Children with ambiguous genitalia, hermaphroditism, or signs and symptoms of CAH admitted to Children's Medical Center were enrolled in the survey, and 101 patients were found. Karyotyping, clinical examination, and paraclinical tests were done. HLA typing was done in patients with proven classical CAH and their parents. HLA antigens were typed in children with CAH-type 21-hydroxylase deficiency. The antigen frequencies were compared with those of the control population. The studies revealed that two HLA antigens, HLA-B18 and HLA-B21, showed a significant increase in frequency. The calculated relative risk value was high, distinguishing the population of patients and their parents. The relative risk among patients was 11.82 for HLA-B18 and 1.75 for HLA-B21 antigens. There was no relationship between HLA-DR antigens and CAH. Studies on the correlation between HLA and CAH indicate an association with HLA-B18 and HLA-B21 antigens, and they can be used as genetic markers of the disorder in the Iranian population, if they are restricted to Iranian patients.     

Antibodies in Histoplasmosis

Production of precipitating and complement-fixing antibody in rabbits and other animals was induced by immunization with live yeast-phase cells of Histoplasma capsulatum. Results of studies of polysaccharide antigens from three strains of H. capsulatum, by quantitative complement-fixation with human and rabbit antisera, strongly suggest the presence of type specificity. The variations of titer during 11 weeks in one patient with histoplasmosis and the variations of titer among a group of patients with histoplasmosis were studied by use of quantitative complement-fixation tests.     

Efficacy of cell-free antigens in evaluating cell immunity and inducing protection in a murine model of histoplasmosis

Histoplasma capsulatum is a dimorphic pathogenic fungus that causes a wide spectrum of disease when mycelial fragments are inhaled. Resistance to H. capsulatum is dependent on cellular immunity mediated by T cells and macrophages. Here we standardized the production of extracts containing cell-free antigens (CFAgs) and observed their efficacy in evaluating cellular immunity during murine histoplasmosis. CFAgs induced a more potent delayed-type hypersensitivity (DTH) response in H. capsulatum-infected mice than did histoplasmin-a classical antigen. This DTH response to CFAgs is able to determine the immune status of infected mice and to predict their death. Moreover, CFAgs stimulated spleen cells from immune mice to produce higher amounts of gamma interferon (IFN-gamma) in vitro. Finally, immunization with CFAgs protected against a lethal inoculum of H. capsulatum. These results demonstrate that CFAgs may be useful for the evaluation of cellular immune response and as a potential source for the development of a vaccine against histoplasmosis.     

播散型组织胞浆菌病研究进展

组织胞浆菌病是由组织胞浆菌引起的深部真菌疾病。播散型组织胞浆菌病为所有临床分型中最为凶险的类型,其特点为起病急、发展快、死亡率高,诊断及治疗也颇为棘手。该病既往被认为是一种地方流行性疾病,多见于美国中西部等西半球地区,我国少见且多为输入性病例。但现阶段我国本土病例也屡有报道,故本文在复习相关文献基础上总结了播散型组织胞浆菌病的流行病学现状、易感人群、临床表现、诊断方法及治疗进展,以飨读者。     

宏基因组学诊断播散型组织胞浆菌病1例

播散型组织胞浆菌病是一种进行性肺外疾病好发于免疫缺陷者。该病诊断的应结合组织胞浆菌病的高危因素(免疫抑制剂、高龄、高风险的暴露等)与临床表现。本文报道一例播散型组织胞浆菌病但免疫功能健全的病例,其表现为亚急性起病,后期病程进展迅速,骨髓涂片及宏基因测序诊断为播散型组织胞浆菌病。予以两性霉素B去氧胆酸盐及伊曲康唑治疗后病情明显好转。     

Isolation of a New Soluble Antigen from the Yeast Phase of Histoplasma capsulatum

A method is described by which a soluble antigen was prepared from the yeast phase of Histoplasma capsulatum. This soluble preparation had a specificity greater than that of whole-cell yeast-phase antigens. In complement fixation tests with sera from human cases of histoplasmosis, blastomycosis, and coccidioidomycosis, the soluble antigen reacted in 12.1% of 141 tests with heterologous sera, whereas conventional whole-cell yeast antigens reacted in 47.3% of 91 tests with heterologous sera. The reactivities of the two types of antigens with homologous sera were essentially the same.     

Soluble Antigens for Immunofluorescence Detection of Histoplasma capsulatum Antibodies

Soluble antigens from Histoplasma capsulatum in the mycelial and yeast phase were purified by gel filtration, fixed onto paper discs, and employed in an indirect immunofluorescence procedure to detect antibody in sera from individuals infected with H. capsulatum. The elution patterns of crude histoplasmin passed through Sephadex G-200 revealed two minor peaks of protein showing immunofluorescence, complement fixing, and precipitating-antigen activity. A large peak containing the pigment and other low molecular weight materials showed no serological activity. A polysaccharide antigen obtained from fragmented, deproteinized yeast-phase cells was reactive in the fluorescent-antibody test but showed no antigen activity in complement fixation or precipitin tests. Although certain sera from culturally proven cases of blastomycosis, coccidioidomycosis, and cryptococcosis reacted with the purified Histoplasma antigens, preliminary evaluation indicated that the immunofluorescence technique may be of value as a screening procedure for the serodiagnosis of histoplasmosis.     

Disseminated histoplasmosis in a SIV-infected rhesus monkey

Disseminated histoplasmosis due to Histoplasma capsulatum was diagnosed in a rhesus monkey inoculated with simian immunodeficiency virus (SIV). Immunohistochemical staining of tissues for viral core antigens revealed that those macrophages that expressed viral antigen contained few or no fungal organisms, while those that were filled with fungal organisms did not express viral antigen. This is a previously undocumented condition in a SIV-infected macaque, and suggests that SIV infection of individual macrophages is not the cause of macrophage dysfunction in SIV infections.     

Diagnostic usefulness of the intradermal test with histoplamin in non-endemic areas of histoplasmosis

The histoplasmosis in Spain is an imported disease presenting in most of case diagnostic difficulties. In this paper, the intradermal skin test with Histoplasma capsulatum antigen as diagnostic method in immunocompetent patients with clinical and radiological signs compatible with histoplasmosis after being visited Central and South American endemic counties, in which this mycosis is endemic. Nine Spanish patients coming from different countries of Latin America with fever and acute respiratory symptoms compatible with histoplasmosis were studied. Other nine accompanying subjects and five controls were also evaluated. Patients underwent mycological cultures and and serological tests for H. capsulatum. Intradermal test with 1% histoplasmine were done in all patients. Serology and skin tests tests were also performed in accompanying people. Intradermal were done in healthy controls. Skin test with histoplasmine were positive in seven of the nine patients. Six of these showed precipitating antibodies against the same antigen. H. capsulatum was only isolated from bone marrow biopsy samples in one patient. The seven patients were given itraconazole by oral route and all symptoms improved after 2 and 4 weeks. In five accompanying subjects the skin test were also positive so that a subclinical histoplasmosis was diagnosed. In the remaining patients and healthy accompanying subjects histoplasmosis infection was excluded. In non endemic geographical areas of histoplasmosis intradermal skin test with histoplasmin when used in immunocompetent individuals is an easy and reliable method for the diagnosis of this mycosis as well as for epidemiological studies.     

Chronic pulmonary histoplasmosis in the State of Rio de Janeiro,Brazil

Three cases of chronic pulmonary histoplasmosis affecting aged patients with chronic obstructive pulmonary disease are reported. They had a history of recurrent episodes of respiratory infection and presented radiological lung lesions inducing a misdiagnosis of chronic pulmonary tuberculosis of the adults. The diagnosis of histoplasmosis, suggested by the immunodiffusion test and the detection of yeastlike cells in smeared and stained sputum, was confirmed by the isolation and identification of Histoplasma capsulatum var. capsulatum in selective media. The treatment was carried out with amphothericin B and ketoconazole or itraconazole. Clinical, radiologic, mycologic and serologic improvement was obtained in all the patients. However, relapses occurred within a period of 1 to 18 months after the interruption of the treatment. Mycological diagnosis and the difficulties observed in the tretament were discussed. In addition data on the epidemiology of histoplasmosis in the state of Rio de Janeiro, Brazil, were presented. This revised version was published online in June 2006 with corrections to the Cover Date.     

Imported and autochthonous histoplasmosis in Italy: new cases and old problems

In the past the Italian soil was considered as a low-endemic pabulum for H. capsulatum var. capsulatum and only few autochthonous cases of histoplasmosis were reported in Italy, especially in the Po valley. The aim of the paper was to evaluate this possibility by reviewing the literature and providing our own personal data. Four additional cases of histoplasmosis were observed during 1999-2003 in AIDS immigrant or in Italian citizens, and in travellers to endemic areas. One of the AIDS patients was an autochthonous case of histoplasmosis. The Italian literature was reviewed. Recent cases and literature data confirm the possible autochthonous presence of histoplasmosis in Italy, especially in the Northern regions.     

Admixture analysis of a rural population of the state of Guerrero, Mexico

We studied 156 individuals of Native American descent from the city of Tlapa in the state of Guerrero in western Mexico. Most individuals' ethnicity was either Nahua, Mixtec, or Tlapanec, but self-identified Mestizos and individuals of mixed ethnicities were also included in the sample. We typed 24 autosomal, one Y-chromosome, and four mitochondrial ancestry-informative markers (AIMs) to estimate group and individual admixture proportions, and determine whether the admixture process involved directional gene flow between parental groups. When genetically defined (GD) Mestizos were excluded from the analysis, Native American ancestry represented approximately 98% of the population's gene pool, while European and West African ancestry represented approximately 1% each. Maternally inherited markers also showed an exceptionally high Native American contribution (98.5%), as did the paternally inherited marker, DYS199 (90.7%). We did not detect genetic structure in this population using these AIMs, which appears consistent with the homogeneity of the sample in terms of admixture proportions. The addition of GD Mestizos to the sample did not produce a considerable change in admixture estimates, but it had a major effect on population structure. These results show that the population of Tlapa in Guerrero, Mexico, has experienced little admixture with Europeans and/or West Africans. They also show that the impact of a small number of admixed individuals on an otherwise homogeneous population might have profound implications on subsequent ancestry/phenotype analysis and mapping strategies. We suggest that heterogeneity is a major characteristic of Mexican populations and, as a consequence, should not be disregarded when designing epidemiological studies of Mexican and Mexican American populations.     

Molecular epidemiology, pathogenesis, and genetics of the dimorphic fungus Histoplasma capsulatum

Histoplasma capsulatum, the causative agent of the most common systemic fungal infection, histoplasmosis, has become subject to increasing study in parallel with rising prevalence of human immunodeficiency. This review presents a summary of the advances made in the investigation of H. capsulatum genomics, molecular epidemiology, pathogenesis, and molecular genetics.     

Evaluation of purified H and M antigens of histoplasmin as reagents in the complement fixation test.

Complement-fixation (CF) tests were performed with purified H and M antigens, histoplasmin, and Histoplasma capsulatum whole cell yeast phase antigen using sera of 126 patients with proven or suspected histoplasmosis. Specific titers for either H or for M antibody were obtained with the individual purified antigens; the highest titers were comparable to those obtained with histoplasmin. However, in sera containing only anti-M antibody, the titers obtained with the purified M antigen were 2 to 16 times those obtained with the histoplasmin or yeast phase antigens. The CF test for either H or M antibody was 4 to 32 times as reactive as the agar-gel microimmunodiffusion test; in general precipitin lines were obtained with either H or M antigens from sera with CF titers greater than or equal to 8. With sera containing H antibody, there was an excellent correlation between the CF titers obtained with purified M antigen and histoplasmin. The correlations of CF titers with H antigen and either histoplasmin or yeast phase antigen were very low.     

Geographical distribution of genetic polymorphism of the pathogen Histoplasma capsulatum isolated from infected bats, captured in a central zone of Mexico

Fourteen Histoplasma capsulatum isolates recovered from infected bats captured in Mexican caves and two human H. capsulatum reference strains were analyzed using random amplification of polymorphic DNA PCR-based and partial DNA sequences of four genes. Cluster analysis of random amplification of polymorphic DNA-patterns revealed differences for two H. capsulatum isolates of one migratory bat Tadarida brasiliensis. Three groups were identified by distance and maximum-parsimony analyses of arf, H-anti, ole, and tub1 H. capsulatum genes. Group I included most isolates from infected bats and one clinical strain from central Mexico; group II included the two isolates from T. brasiliensis; the human G-217B reference strain from USA formed an independent group III. Isolates from group II showed diversity in relation to groups I and III, suggesting a different H. capsulatum population.     

Outbreak of acute histoplasmosis in a family group: identification of the infection source

An outbreak of acute histoplasmosis occurring in 4 members of the same family, two women, a girl and a male, is reported. The index case presented acute respiratory symptoms, severe enough to require hospitalization. In the remaining persons, the infection was asymptomatic but was evidenced by reactive histoplasmin serologic tests. Search for the common source of infection led to an enriched soil obtained in a local nursery for growing in-door plants. BALB/c mice were inoculated with suspensions of soils from the potted plants. Histoplasma capsulatum var. capsulatum was isolated from various internal organs of the mice. Although histoplasmosis is observed more frequently in persons with occupations implying risk of exposure and is connected to rural areas, outbreaks and intra-family cases are now common in urban areas. This is due to massive urbanization, deforestation, demolitions and the use of soils enriched with organic compounds, mainly bird/bat excrements. This report calls the attention on the danger involved in using such enriched soils for plant nutrition.