Thermotolerance of Histoplasma capsulatum at 40 °C predominates among clinical isolates from different Latin American regions

ABSTRACT The yeast phase of 22 Histoplasma capsulatum clinical isolates from Mexico, Argentina, Colombia, and Guatemala and three reference strains, one from Panama and two from the United States of America (USA), were screened for thermosensitivity characteristics using different analyses. Growth curves at 0, 3, 6, 12, 24, and 30 h of incubation at 37 and 40 °C, the growth inhibition percentage at 40 °C, and the doubling time at 37 and 40 °C were determined for all yeasts studied. Most of the isolates examined exhibited thermotolerant phenotypes at 40 °C, whereas a thermosensitive phenotype at 40 °C was only detected in the Downs reference strain from the USA. Growth inhibition values lower than 33.8% supported the predominance of the thermotolerant phenotype at 40 °C. The doubling time means found for the different isolates were 5.14 h ± 1.47 h at 37 °C and 5.55 h ± 1.87 h at 40 °C. This is the first report to underscore the predominance of thermotolerant and delayed doubling time phenotypes in H. capsulatum clinical isolates from different regions of Latin America.

Postpartum histoplasmosis in an HIV-negative woman: a case report and phylogenetic characterization by internal transcribed spacer region analysis

Abstract The present report describes the first case of postpartum disseminated histoplasmosis in a 24-year-old HIV-negative woman. On the tenth day after vaginal delivery, the patient presented with dyspnea, fever, hypotension, tachycardia, and painful hepatomegaly. Yeast-like Histoplasma capsulatum features were isolated in the buffy coat. The phylogenetic analysis demonstrated that the fungal isolate was similar to other H. capsulatum isolates identified in HIV patients from Ceará and Latin America. Thus, histoplasmosis development in individuals with transitory immunosuppression or during the period of immunological recovery should be carefully examined.

The use of nested Polymerase Chain Reaction (nested PCR) for the early diagnosis of Histoplasma capsulatum infection in serum and whole blood of HIV-positive patients* / Uso da Reação em Cadeia da Polimerase aninhada (PCR aninhada) para o diagnóstico precoce da infecção pelo Histoplasma capsulatum no soro e no sangue total de pacientes HIV positivos

The aim of the study was to detect the rDNA sequences and their regions in Histoplasma capsulatum, which could be considered species-specific and used as a molecular method for this diagnosis by the technique of nested polymerase chain reaction (nested PCR), employing specific sequences (primers) for H. capsulatum: 18S rDNA region (HC18), 100 kDa (HC100) and the sequence 5.8 S-ITS rDNA (HC5.8). The PCR sequences HC18, HC100 and HC5.8 resulted in a specificity of 100%. The molecular assays may increase the specificity, sensitivity and speed in the diagnosis of Histoplasmosis.

O objetivo do estudo consistiu em detectar seqüências no ADNr e as suas regiões no Histoplasma capsulatum, que pudessem ser consideradas espécie-específicas e usadas como método molecular para o diagnóstico pela técnica da reação em cadeia da polimerase aninhada ("nested PCR") com seqüências específicas ("primers") para H. capsulatum: regiões 18S ADNr (HC18), 100kDa (HC100) e a seqüência 5.8 S ADNr-ITS (HC5.8). A "nested PCR" com as seqüências HC18, HC100 e HC5.8 resultaram em 100% de especificidade. Os ensaios moleculares podem aumentar a especificidade, sensibilidade e rapidez na diagnose da Histoplasmose.

A rare case of Histoplasma fungemia in an AIDS patient.

Disseminated cases of histoplasmosis in acquired immune deficiency syndrome (AIDS) are rarely reported from India. Most of these cases report isolation of this fungus from the bone marrow, lymph node aspirate, spleenic aspirate, and biopsies. We report isolation of Histoplasma capsulatum from the blood of an AIDS patient. A 30-year-old male from Utter Pradesh was admitted with fever, loss of appetite, and nausea since two months. Few intracellular and extracellular budding cells were observed on bone marrow examination on the fifth day of admission. Diagnosis was confirmed by blood cultures taken on the 11th day of admission. Amphotericin B was started, but the patient's condition deteriorated and he died.

Oropharyngeal histoplasmosis: report of eleven cases and review of the literature / Histoplasmose orofaríngea: relato de onze casos e revisão da literatura

INTRODUCTION: Histoplasmosis is a systemic mycosis endemic in Brazil, especially in the State of Rio Grande do Sul, where Histoplasma capsulatum was isolated from the soil. H. capsulatum may compromise unusual areas, including the oropharynx, particularly in patients presenting disseminated histoplasmosis; which is associated with a state of immunosuppression, such as AIDS. METHODS: During database analysis of a total of 265 cases of histoplasmosis, the medical records of 11 patients with histological or microbiological diagnoses of oral histoplasmosis (OH) between 1987 and 2008 were retrospectively reviewed. RESULTS: This work reports 11 cases of OH, the majority presenting histopathological or microbiological evidence of disseminated histoplasmosis (DH). In the patients with DH, OH was the first manifestation of histoplasmosis. Five of the 11 patients discussed were HIV-seropositive with clinical and laboratory findings of AIDS. Four patients presented active pulmonary tuberculosis concomitant with histoplasmosis. Treatment was based on the use of itraconazole and amphotericin B deoxycholate. Eight patients responded successfully to therapy after one year, two did not come back for reevaluation and one died despite adequate therapy. CONCLUSIONS: Oral histoplasmosis is closely associated with immunosuppression status, especially in patients presenting AIDS; moreover, in many cases, OH is the first sign of disseminated histoplasmosis.

INTRODUÇÃO: Histoplasmose é uma micose sistêmica, endêmica no Brasil, especialmente no Estado do Rio Grande do Sul, onde Histoplasma capsulatum foi isolado do solo. H. capsulatum pode acometer áreas não-usuais, como cavidade orofaríngea, particularmente em pacientes com histoplasmose disseminada, por sua vez, associada com estado de imunossupressão, como na AIDS. MÉTODOS: A partir de 265 casos de histoplasmose em um banco de dados de um laboratório de micologia, foram analisados retrospectivamente 11 prontuários de pacientes com diagnóstico histológico ou microbiológico de histoplasmose oral (HO) entre 1987 e 2008. RESULTADOS: Reportamos neste trabalho onze casos de HO, a grande maioria com evidências histopatológicas e microbiológicas de histoplasmose disseminada (HD). Nos pacientes com HD, HO foi a primeira manifestação de histoplasmose. Cinco dos onze casos relatados eram portadores do vírus do HIV, todos com diagnóstico clínico e laboratorial de AIDS. Quatro pacientes do total tinham concomitantemente tuberculose pulmonar e histoplasmose. Tratamento foi baseado no uso de itraconazol e anfotericina B principalmente. Oito pacientes tiveram sucesso terapêutico após um ano, dois não retornaram para reavaliação e um faleceu apesar da adequada terapia antifúngica. CONCLUSÕES: Histoplasmose oral está associada muitas vezes com estado de imunossupressão, especialmente em pacientes com AIDS. Em muitos casos pode representar o primeiro sinal indicativo de histoplasmose disseminada.

Gastrointestinal Histoplasmosis Mimicking Abdominal Tuberculosis.

We report an elderly male who presented with history of chronic diarrhoea. The patient underwent colonoscopy and CT scan of the abdomen which strongly suggested tuberculosis; however histopathology showed presence of budding forms of Histoplasma capsulatum. The patient was started on oral itraconazole on which he improved remarkably. ©

Histoplasmosis pulmonar diseminada (enfermedad de Darling): a propósito de un caso / Disseminated pulmonary histoplasmosis (Darling's disease): a purpose of a case

La histoplasmosis es una micosis sistémica que afecta al hombre y a los animales, causada por el Hongo Histoplasma capsulatum, se relaciona especialmente con el guano de las aves, y las cuevas habitadas por murciélagos. La infección se produce habitualmente por vía respiratoria, raramente la puerta de entrada es cutánea. El mecanismo de contagio es a través de la inhalación de esporas en el polvo del aire; la población más afectada es la que vive en zonas rurales, especialmente los granjeros; este padecimiento también se ha presentado en forma epidémica. Es una enfermedad de variada, manifestación clínica que puede ir de una simple infección respiratoria asintomática, hasta una enfermedad diseminada, caracterizada por fiebre, anemia progresiva, hepatoesplenomegalía, linfadenopatías, úlceras en el aparato digestivo y necrosis de suprarrenales. Ocurre con mayor frecuencia en individuos del sexo masculino sin distinción de raza. El tratamiento es a base de derivados del imidazol: ketoconazol, itraconazol, fluconazol y anfotericina B.

Comparación de las coloraciones de Giemsa y Grocott en el diagnóstico de la histoplasmosis / Comparison of Giemsa and Grocott stains in the diagnosis of histoplasmosis

El diagnóstico de histoplasmosis se realiza tradicionalmente mediante el reconocimiento de típicas levaduras intracelulares de Histoplasma capsulatum en preparaciones microscópicas teñidas con Giemsa. Se comparó la eficacia de una modificación rápida de la técnica de Grocott (MRG) y la tradicional de Giemsa para el diagnóstico de la histoplasmosis, a partir de la aplicación de ambas a 10 secreciones respiratorias, 8 escarificaciones de lesiones cutáneas y una biopsia ganglionar, pertenecientes todas a pacientes con sospecha clínica de esta micosis. En 15 de las 19 muestras no se encontraron diferencias significativas en la capacidad y rapidez para arribar al diagnóstico, mientras que en las 4 restantes, fueron reconocidas con la MRG estructuras que pasaron desapercibidas con la coloración de Giemsa. La modificación rápida permitió un reconocimiento más rápido del H. capsulatum en materiales donde este hongo se observó en escaso número y permitió además identificar con seguridad otros patógenos fúngicos diferentes de H. capsulatum, como Pneumocystis jiroveci, Paracoccidioides brasiliensis y Cryptococcus neoformans, difíciles de observar con la coloración de Giemsa. Se propone la técnica de Grocott o su modificación rápida para el diagnóstico de la histoplasmosis, especialmente cuando el empleo de la coloración de Giemsa da lugar a resultados negativos o dudosos.

The diagnosis of histoplasmosis is traditionally achieved by recognizing the typical intracellular yeasts of Histoplasma capsulatum, in smears stained with Giemsa stain. The usefulness of a rapid modification of Grocott and of traditional Giemsa stains for the diagnosis of histoplasmosis was compared applying both techniques in 10 respiratory secretions, 8 cutaneous lesions scrapings and 1 adenomegaly biopsy, all of them belonging to patients with clinically suspected histoplasmosis. In 15 out of the 19 evaluated samples, no significant differences were found in the ability or speed to reach the diagnosis with the applied techniques; while in the remaining 4 samples, structures that had not been observed with Giemsa stain were recognized with the rapid modification. The modification enabled quicker recognition of H. capsulatum than Giemsa stain in those clinical samples where the number of these fungal pathogens was scant. Additionally, the rapid modification also enabled the recognition of fungal pathogens other than H. capsulatum, as Pneumocystis jiroveci, Paracoccidioides brasiliensis and Cryptococcus neoformans, difficult to observe with the Giemsa stain. Use of Grocott technique or rapid modification stain is proposed for the diagnosis of histoplasmosis, when the result obtained with the Giemsa stain is doubtful or negative.

Histoplasma capsulatum fungemia in patients with acquired immunodeficiency syndrome: detection by lysis-centrifugation blood-culturing technique

Progressive disseminated histoplasmosis (PDH) is an increasingly common cause of infection in patients with acquired immune deficiency syndrome (AIDS). We report 21 cases of PDH associated with AIDS diagnosed by lysis-centrifugation blood culture method. The most prevalent clinical findings were fever, weight loss, respiratory symptoms, and mucocutaneous lesions. Chest roentgenogram showed diffuse pulmonary infiltrates in 13 of 21 patients (62 percent). Brochoalveolar fluid has yelded positive culture in four patients only in medium with cycloheximide.

Histoplasmose progressiva disseminada (HPD) tem aumentado e é causa comum de infecção em pacientes com síndrome da imunodeficiência adquirida (Aids). Relatamos 21 casos de HPD associado com Aids diagnosticada pela técnica de hemocultivo por lise-centrifugação. Os achados clínicos mais prevalentes foram febre, perda de peso, sintomas respiratórios e lesões mucocutâneas. Raios X de tórax mostrou infiltrados pulmonares difusos em 13 dos 21 pacientes (62 por cento). Amostras de lavado broncoalveolar foram positivos em apenas 4 pacientes através de meio com cicloheximida.

Disseminated histoplamosis.

A case of disseminated histoplasmosis in a 45-year-old male patient with acquired immunodeficiency syndrome (AIDS) from Pune is reported. The patient presented with high-grade fever and pain in hypochondrium. Clinical signs were pallor and hepatosplenomegaly. Bone marrow and splenic aspirate revealed numerous intracellular oval shaped yeast forms. Histoplasma capsulatum was isolated from the bone marrow and splenic aspirate. H. capsulatum infection is an opportunistic infection usually reported from patient with AIDS in areas endemic for H. capsulatum. The present case highlights the fact that histoplasmosis could be an emerging opportunistic infection in India.

Disseminated histoplasmosis in HIV positive patients in Espírito Santo state, Brazil: a clinical-laboratory study of 12 cases (1999-2001)

Twelve cases of histoplasmosis in HIV-infected patients were found in a retrospective analysis at the Hospital Universitário Cassiano Antônio de Moraes of the Universidade Federal do Espírito Santo (HUCAM), Vitória (ES), from June 1999 to May 2001. The frequency of histoplasmosis among HIV-positive patients was 2.1 percent in the infectious diseases division of the hospital during this period. Histoplasmosis compromised mainly males (11/12), 27 to 44 years old, and residents of the metropolitan urban area (10/12). Alcohol abuse and tobacco smoking were described in 10 of the 12 patients. For all patients, this was the first opportunistic infection. Two of the 12 patients died; 10 patients had disseminated disease, one patient had an intestinal presentation and one had disease restricted to the lungs. The most frequent clinical manifestations were weight loss, fever, hepatomegaly and splenomegaly, coughing, abdominal pain, and diarrhea. Six of the 12 patients had skin lesions. Time of symptoms preceding the diagnosis varied from two months to one year. CD4 counts were below 200 cells/mm³ in 9 of 10 patients. Diagnosis was made by histology in two thirds of the patients. The typical adult patient with HIV infection and histoplasmosis in our series was male, had a CD4 count below 200 cells/mm³, had fever, weight loss, cough, abdominal pain and hepatomegaly in the last two months or more, had a high probability of alcohol and tobacco addiction, was having his first opportunistic infection, and had no identifiable environmental exposure risk.

Disseminated histoplasmosis mimicking laryngeal carcinoma from central India--a case report.

A 58 year old male, chronic smoker, with diabetes mellitus (Type II), residing in Madhya Pradesh presented with dysphagia, hoarseness, odynophagia and significant weight loss. Microlaryngoscopy showed reddish ulcerated area involving valleculae, and pharyngo-epiglottic fold. Histopathological examination showed foamy macrophages containing Histoplasma capsulatum. Patient initially responded to Azoles, relapsed three months after stopping the treatment and presented with oral lesions. Biopsy showed H. capsulatum, histologically as well as on culture. The mycelial phase converted to yeast phase on B.H.I.A. at 37 degrees C confirming the isolate as H. capsulatum. The patient responded well to amphotericin B.

Primer aislamiento de Histoplasma capsulatum de murciélago urbano Eumops bonariensis / First isolation of Histoplasma capsulatum from the urban bat Eumops bonariensis

Se comunica el primer aislamiento de Histoplasma capsulatum var. capsulatum de un murciélago macho de la especie Eumops bonariensis, capturado en la ciudad de Buenos Aires en 2003. Los aislamientos fueron recuperados de bazo e hígado e identificados fenotípicamente. Se los comparó por PCR, con 17 aislamientos clínicos, 12 de pacientes residentes en la ciudad de Buenos Aires y cinco de otros países de América, usando los iniciadores 1283, (GTG)5, (GACA)4 y M13. Con los cuatro iniciadores, los perfiles de los aislamientos de murciélago resultaron idénticos entre sí y más relacionados a los de pacientes de Buenos Aires que a los de otros países (porcentaje de similitud: 91-100% y 55-87%, respectivamente). La alta relación genética entre los aislamientos obtenidos del murciélago y de los humanos residentes en Buenos Aires sugiere una fuente común de infección. Este es el primer registro de E. bonariensis infectado con H. capsulatum en el mundo, y el primer aislamiento del hongo en la población de quirópteros de la Argentina. Así como estos mamíferos actúan como reservorio y dispersan el hongo en la naturaleza, la infección en murciélagos urbanos podría asociarse al elevado número de casos de histoplasmosis entre pacientes inmunodeprimidos en la ciudad de Buenos Aires.

We report the first isolation of Histoplasma capsulatum var. capsulatum from a male bat Eumops bonariensis captured in Buenos Aires city in 2003. The pathogen was recovered from spleen and liver specimens, and was identified by its phenotypic characteristics. PCR with primers 1283, (GTG)5, (GACA)4 and M13 was used to compare both bat isolates with 17 human isolates, 12 from patients residing in Buenos Aires city, and 5 from other countries of the Americas. The profiles obtained with the four primers showed that both bat isolates were identical to each other and closer to Buenos Aires patients than to the other isolates (similarity percentage: 91-100% and 55-97%, respectively). The high genetic relationship between bat isolates and those from patients living in Buenos Aires suggests a common source of infection. This is the first record of E. bonariensis infected with H. capsulatum in the world, and the first isolation of the fungus in the Argentinean Chiroptera population. In the same way as these wild mammals act as reservoir and spread the fungus in the natural environment, infection in urban bats could well be associated with the increase in histoplasmosis clinical cases among immunosuppressed hosts in Buenos Aires city.

Histoplasmose pulmonar aguda: relato de uma microepidemia / Acute pulmonary histoplasmosis: report of an outbreak

Os autores relatam uma microepidemia de histoplasmose pulmonar, com cinco crianças que desenvolveram a doença em um período de 7 a 14 dias após a limpeza de um forno desativado para produção de carvão vegetal. Todas apresentaram quadro de febre alta persistente, tosse seca, astenia e anorexia, com 28 dias de evolução. Quando buscaram atendimento médico, uma delas encontrava-se taquipnéica, febril, com hepatomegalia e palidez cutânea, estando as restantes em regular estado geral e já sem febre. As radiografias de tórax demonstravam, em todos os casos, infiltrados reticulonodulares grosseiros, difusos e bilaterais, além de linfonodomegalias hilares. As tomografias computadorizadas evidenciaram pequenos nódulos difusos, com distribuição aleatória, além das linfonodomegalias. Os diagnósticos foram confirmados por meio da imunodifusão em gel para Histoplasma capsulatum, que foi positiva em todas as amostras pareadas coletadas com 15 dias de intervalo. Apenas uma criança necessitou de internação, por causa de importante queda no estado geral, sendo realizado tratamento de suporte e observação. Todas as crianças evoluíram com melhora clínica, sem o uso de antifúngicos, e foram submetidas a tomografias de controle após cerca de 50 dias, que demonstraram importante regressão das lesões.

The authors report a pulmonary histoplasmosis outbreak occurring in five children after the cleaning of a deactivated coal furnace. The symptoms were high fever, dry cough, asthenia and anorexia. By the time parents seeked for medical care, only one child remained symptomatic with fever, tachypnea and hepatomegaly. All the patients had similar radiological findings. Chest films showed diffuse, bilateral, reticulonodular infiltrates and lymph node enlargement. Computed tomography showed small nodules with a random distribution and hilar and mediastinal lymph nodes. Diagnosis was confirmed by positive gel immunodiffusion for Histoplasma capsulatum. Only one patient needed to be hospitalized to receive supportive treatment. The use of antifungal agents was not necessary in any of the patients. After 50 days all patients were submitted to computed tomography studies that revealed significant remission of the lesions.

Disseminated histoplasmosis in an AIDS patient diagnosed on bone marrow.

A 29 year old male drug addict, who was HIV positive presented with fever and hepatosplenomegaly. Bone marrow examination revealed Histoplasma capsulatum confirmed by PAS & GMS stains. However patient had a rapid downhill course with multiorgan failure and died before specific treatment could be instituted.