Histoplasma capsulatum peritonitis associated with continuous ambulatory peritoneal dialysis

This paper reports a case of infection byHistoplasma capsulatum apparently restricted to the peritoneum in a woman submitted to continuous ambulatory peritoneal dialysis. Diagnosis was established by culture of dialysis fluid and peritoneal nodule and by histopathologic examination.     

Deactivation of macrophage oxidative burstin vitro by different strains ofHistoplasma capsulatum

It was previously reported thatHistoplasma capsulatum (Hc) yeast not only failed to stimulate a murine macrophage oxidative burst (OB), but they also blunted or abolished OB stimulation by a subsequent encounter with potent stimuli such as zymosan or phorbol 12-myristate 13-acetate (PMA). The present studies show that macrophage deactivation is proportional to the time of incubation and the dose of Hc yeast that induce the deactivated state. Hc yeast derived from a virulent strain (G217B) are more efficient inducers of macrophage deactivation than similar preparations derived from the avirulent Downs Hc strain. Yeast cells of two other pathogenic fungi,Candida albicans andCryptococcus neoformans are shown to stimulate rather than deactivate a macrophage OB.     

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。     

Epididymal histoplasmosis diagnosed by isolation ofHistoplasma capsulatum from semen

An autochthonous case of epididymal histoplasmosis masquerading as tuberculosis in a 55-year-old male patient is reported from India. It was diagnosed by culture ofHistoplasma capsulatum from semen and by demonstration of the fungus upon re-examination of epididymal biopsy sections previously misinterpreted as tuberculous granuloma. The patient's main complaints were painful epididymal swelling, occasional fever and cough. He was treated successfully by excision of epididymis and vas deferens combined with amphotericin B therapy. This is believed to be the first case of epididymal histoplasmosis to be reported outside the American continent and the fourth of its type reported in the English literature. The case is also noteworthy in thatH. capsulatum was isolated for the first time from semen, and it underlines the importance of mycological culture of semen specimens for diagnosis of genitourinary infections of obscure etiology.Presented at the XII Congress of the International Society for Human and Animal Mycology, Adelaide, Australia, March 13–18, 1994.     

Detection of an antigenic cell wall layer inHistoplasma capsulatum

Histoplasma capsulatum yeast cells have been studied by immunoelectron microscopy using rabbit polyclonal antisera and a biotin-avidin-peroxidase detection system. An antigenic surface layer has been visualized in the cell wall of immunostained organisms. This layer was not seen in samples prepared by standard electron microscopic methods or in negative controls used with the immunocytochemical technique. Without immunostaining the cell wall ofHistoplasma appeared almost transparent. In contrast, after immunoperoxidase staining the cell wall was conspicuous, bounded by the darkly stained outer layer. This electron dense layer, appeared to be a reservoir of surface antigens that were recognized by anti-Histoplasma antibodies.Abbreviations CHHA Cystine-heart-hemoglobin agar - PBS phosphate buffered saline - Ig immunoglobulin - TBS Tris buffered saline - DAB 3,3-diaminobenzidine tetrachloride - FITC fluorescein isothiocyanate - M199 tissue culture medium 199, according to Morgan et al. (1950)     

Genetic diversity of Histoplasma capsulatum strains in Brazil

This study establishes the genetic relatedness among Brazilian Histoplasma capsulatum samples obtained from different sources. A PCR-based random amplified polymorphic DNA (RAPD) assay was used to delineate polymorphisms among isolates in geographically diverse regions in Brazil. RAPD fingerprints revealed distinct DNA profiles and provided a high level of discrimination among H. capsulatum strains from different locations. Cluster I was composed of H. capsulatum isolates from the northeast region. The majority of strains from southeast and south were categorized as major cluster II. The strain 84564 from Rio de Janeiro State showed no genetic correlation to any of the isolates from the same state. The RAPD patterns of H. capsulatum isolates from Goias (Cluster III) were unrelated to DNA fingerprints observed among the other H. capsulatum strains (48% similarity). This study is the first report that stratifies the clusters of H. capsulatum strains from Brazil by molecular typing and associates them with the geographical origin.     

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.     

Electrophoresis karyotype and chromosome-length polymorphism of Histoplasma capsulatum clinical isolates from Latin America

Intact chromosomes of 19 clinical isolates of Histoplasma capsulatum recently obtained in Argentina, Mexico and Guatemala and the laboratory reference strain G186B from Panama were analyzed using pulsed-field gel electrophoresis. Chromosomal banding patterns of the human isolates revealed 5-7 bands, ranging from 1.3 to 10 Mbp in size. Strain G186B showed five bands of approximately 1.1, 2.8, 3.3, 5.4 and 9.7 Mbp. Thirteen different electrokaryotypes were identified, indicating that the genome of H. capsulatum varies widely in nature, as observed previously in laboratory strains. No definite association was found between electrokaryotype and geographical or clinical source.     

有关SARS病原冠状病毒合并感染组织胞浆菌的探讨

目的探讨SARS病原学的冠状病毒复合组织胞浆菌感染的问题。方法对象为SARS患者尸检1例和南猴(某猴场病死猴)尸检1例,采用病理组织学和免疫组化荧光检测的方法作检查,观察和比较两者尸检材料肺、脾、淋巴结和肝的病理变化和组织内组织胞浆菌的存在。结果1.人SARS和南猴的病理组织学改变极为相似。2.免疫组化结果表明,用人SARS恢复期血清和兔抗组织胞浆菌血清与组织胞浆菌抗原均呈阳性反应,显示此例SARS患者曾感染组织胞浆菌,其次用此两种抗血清分别与人SARS和南猴肺、脾、淋巴结尸检材料反应,均有组织胞浆菌阳性菌体的存在,说明人SARS和南猴脏器均有组织胞浆菌的感染。结论人SARS病原除冠状病毒外,还有组织胞浆菌的合并感染。