Evaluation of a Microtiter Latex Agglutination Test for Histoplasmosis

Experiments were designed to evaluate a Microtiter latex agglutination (Micro-LA) test, as a serological aid in the diagnosis of histoplasmosis, and to compare this test with the conventional microtiter-complement fixation (CF) test for histoplasmosis. Sera tested were from cases of acute and chronic pulmonary and disseminated histoplasmosis, as well as from individuals not having histoplasmosis. Ninety-seven percent of the cases of acute pulmonary histoplasmosis had positive Micro-LA tests, whereas 91% had positive CF tests. Ninety-six percent of the patients having chronic pulmonary histoplasmosis showed positive Micro-LA tests and 91% had positive CF tests. In contrast, 64% of the cases of disseminated histoplasmosis had positive Micro-LA tests, whereas 82% had positive CF tests. None of these differences was statistically significant. Although there were no significant differences in complement fixing and agglutinating antibody cross-reactivity with Blastomyces antigens, more patients demonstrated CF titers than Micro-LA titers. Sera from patients with acute and chronic histoplasmosis showed higher Micro-LA titers than CF titers, whereas sera from cases of disseminated histoplasmosis showed higher CF titers. Histoplasmin skin testing has less of a boosting effect on agglutinating antibodies than on CF antibodies to histoplasmin. Anticomplementary sera can be used in the Micro-LA test. This test is simple to perform, and results can be obtained in 2 to 4 hr.     

Histoplasmosis in HIV-Infected Patients: Epidemiological,Clinical and Necropsy Data from a Brazilian Teaching Hospital

Histoplasmosis occurs in 5–10% of HIV-infected patients in endemic areas and evolves to severe and disseminated infection with mortality rates over 50% in some regions. This report presents epidemiological, clinical and outcome data from HIV-infected patients with histoplasmosis confirmed by culture and/or at necropsy who were admitted to a Brazilian teaching hospital. Data from 65 patients were obtained from their respective medical and necropsy records. From 2005 to 2018, 36 HIV-infected patients were diagnosed with histoplasmosis confirmed by culture. At admission, most of these patients presented disseminated fungal infection, whereas 15 (41.7%) were simultaneously diagnosed with both HIV infection and histoplasmosis. Fever, weight loss, hepatosplenomegaly, respiratory and digestive symptoms were present in 86.2%, 50%, 44.4% and 41.7% of the patients, respectively. At admission, 24 patients had low CD4 T-cell count and high viral load values. Among the 30 patients who received antifungals, 16 (53.3%) were cured, 13 (43.3%) died, and one was lost to follow-up. Six patients died prior to therapy. From 1990 to 2018, 63 necropsies of patients with Histoplasma capsulatum infection were performed. Of these patients, 29 (46.0%) were HIV-infected individuals, including 21 (72.4%) who presented disseminated histoplasmosis and 21 (72.4%) who were diagnosed with histoplasmosis at necropsy. The epidemiological, clinical and outcome profiles presented herein are similar to those described elsewhere and reinforce the difficulties that are still present in limited-resource settings where advanced immunodeficiency, combined with severe fungal infection and late patient admissions, is related to poor outcomes.

     

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。     

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.     

Risk Factors for Disseminated Histoplasmosis in a Cohort of HIV-Infected Patients in French Guiana

Disseminated histoplasmosis is the first AIDS-defining infection in French Guiana. A retrospective cohort study studied predictive factors of disseminated histoplasmosis in HIV-infected patients between 1996 and 2008. Cox proportional hazards models were used. The variables studied were age, sex, last CD4/CD8 count, CD4 nadir, herpes or pneumocystosis, cotrimoxazole and fluconazole use, antiretroviral treatment and the notion of recent initiation of HAART. A total of 1404 patients were followed for 6833 person-years. The variables independently associated with increased incidence of disseminated histoplasmosis were CD4 count<50 per mm3, CD4 count between 50 and 200 per mm3, a CD4 nadir <50 per mm3, CD8 count in the lowest quartile, herpes infection, and recent antiretroviral treatment initiation (less than 6 months). The variables associated with decreased incidence of histoplasmosis were antiretroviral treatment for more than 6 months, fluconazole treatment, and pneumocystosis. There were 13.5% of deaths at 1 month, 17.5% at 3 months, and 22.5% at 6 months after the date of diagnosis of histoplasmosis. The most important predictive factors for death within 6 months of diagnosis were CD4 counts and antiretroviral treatment. The present study did not study environmental/occupational factors but provides predictive factors for disseminated histoplasmosis and its outcome in HIV patients in an Amazonian environment during the HAART era.     

Gastrointestinal disseminated histoplasmosis in HIV-infected patients: A descriptive and comparative study

Disseminated histoplasmosis is one the main AIDS-defining opportunistic infections in HIV-infected patients, notably in Latin America. The non-specific and proteiform clinical presentation leads to diagnostic delays that may lead to fatal outcomes. This retrospective multicentric study aimed to describe the frequency and manifestations of gastrointestinal histoplasmosis in French Guiana, and to compare patients with disseminated histoplasmosis with or without gastrointestinal involvement.Between January 1, 1981 and October 1, 2014 co-infections with HIV and histoplasmosis were enrolled. Inclusion criteria were: age >18 years, confirmed HIV infection; first proven episode of histoplasmosis.Among 349 cases of disseminated histoplasmosis, 245 (70%) had a gastrointestinal presentation. Half of patients with gastrointestinal signs had abdominal pain or diarrhea, mostly watery. Half of patients with abdominal pain had diarrhea (63/124) and half of those with diarrhea (63/123) had abdominal pain. A significant proportion of patients also had hepatomegaly and, to a lesser degree, splenomegaly. After adjusting for potential confounding, the presence of lymphadenopathies >2cm (AOR = 0.2, IC95 = 0.04–0.7, P = 0.01), Haitian origin (AOR = 0.04, IC95 = 0.004–0.4, P = 0.006) were associated with a lower prevalence of gastrointestinal signs and positive gastrointestinal presence of H. capsulatum. Persons with a gastrointestinal H. capsulatum were more likely to have a decreased prothrombin time, lower ferritin, lower liver enzymes, and lower concentrations of LDH than those without gastrointestinal signs and symptoms. They also had a shorter interval between symptoms onset and diagnosis. Patients with a positive gastrointestinal identification of H. capsulatum were less likely to die at 1 month than those without a gastrointestinal presentation (respectively, 4.6% vs 18.5%, P = 0.01).Subacute or chronic gastrointestinal presentations are very frequent during disseminated histoplasmosis, they seem less severe, and should lead to suspect the diagnosis in endemic areas. There were populational or geographic differences in the frequency of gastrointestinal manifestations that could not be explained.     

Histoplasmosis in Montreal During the Fall of 1963, with Observations on Erythema Multiforme

Although Montreal is in an endemic area, significant clinical histoplasmosis with systemic manifestations has been, until recently, infrequently diagnosed. However, since the autumn of 1963, 31 cases of clinically significant histoplasmosis have been seen by the authors. These were divided into two groups: (1) patients in whom the diagnosis was established on the basis of histological and/or cultural demonstration of the fungus; (2) patients in whom the diagnosis was based on a positive histoplasmin skin test, a complement fixation antibody titre of 1:32 or greater and compatible clinical and radiological findings. An additional group of 11 patients who presented with erythema multiforme was investigated and a heretofore unrecognized relationship between histoplasmosis and erythema multiforme was established.     

Chronic Cavitary Histoplasmosis of the Lung

Four main clinical types of disease result from infection by the fungus Histoplasma capsulatum: (1) the primary complex; (2) acute pulmonary histoplasmosis; (3) chronic cavitary pulmonary histoplasmosis; (4) disseminated systemic histoplasmosis.Chronic cavitary histoplasmosis of the lung is indistinguishable clinically and radiographically from pulmonary tuberculosis. In this disease, however, the histoplasmin skin test and the histoplasmin complement fixation test are positive in more than 80% of cases and sputum cultures are usually positive for Histoplasma capsulatum. The mortality rate of the chronic cavitary type is greater than 30%. The antibiotic, amphotericin B, is the most effective drug in treatment. If surgical resection of the cavitary lesion is feasible, under amphotericin coverage, this is the treatment of choice.During the past year, two patients with chronic cavitary histoplasmosis illustrating the aforementioned features were diagnosed at the Toronto Hospital for Tuberculosis.     

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.     

High prevalence and mortality due to Histoplasma capsulatum in the Brazilian Amazon: An autopsy study

BackgroundHistoplasmosis is acquired by inhalation of spores of the dimorphic fungus Histoplasma spp. Although this pathogen is distributed worldwide, it is more prevalent in the Americas. However, the real burden of histoplasmosis remains undefined in many endemic regions.MethodologyWe conducted a series of 61 autopsies to individuals who died in a hospital in the Brazilian Amazon focused on infectious diseases. We performed a detailed histological and microbiological evaluation with genetic characterization of Histoplasma strains with the aim to evaluate the contribution of histoplasmosis to morbidity and mortality. Additionally, we assessed the clinicopathological correlation.Principal findingsEvidence of Histoplasma infection was detected in 21 patients (34%). Eight cases were disseminated infections, all of them occurred in HIV-positive patients. Six cases were localized histoplasmosis, limited to the lungs. In seven patients Histoplasma DNA was detected by PCR in patients with no histological lesions. Histoplasma infection was detected in 38% of HIV-positive patients and was a major contributor to death in 22% of them. Lungs, liver and spleen were affected in all cases of disseminated histoplasmosis. Phylogenetic analysis of the strains suggested a high diversity of Histoplasma species circulating in the Brazilian Amazon. Histoplasmosis was clinically missed in 75% of the disseminated infections.ConclusionsThe high incidence of histoplasmosis, the low index of clinical suspicion, and the severity of the disseminated disease highlight the need of proactively implementing sensitive routine screening methods for this pathogen in endemic areas. Antifungal prophylaxis against Histoplasma should be encouraged in the severely immunocompromised HIV patients in these areas. In conclusion, substantial mortality is associated with disseminated histoplasmosis among HIV-positive patients in the Brazilian Amazon.     

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.     

Histoplasma capsulatum in the environment of sporadic histoplasmosis cases

Conclusions 1. Acute pulmonary histoplasmosis in adults is demonstrated to be associated with exogenous sources of infection in one-half of a series of cases. 2. No exogenous sources of infection were found in chronic pulmonary histoplasmosis in adults by methods comparable to those used in acute pulmonary histoplasmosis. 3. The significance of these findings for the pathogenesis of the three clinical forms of histoplasmosis is discussed. 4. In acute pulmonary histoplasmosis in adults, the isolation ofH. capsulatum from the environment at sites of exposure aided in specific diagnosis.Two acute pulmonary histoplasmosis cases were reported previously (2–3).     

The protein "mycoarray": a novel serological assay for the laboratory diagnosis of primitive endemic mycoses

A protein microarray containing fungal antigens (the "mycoarray") has been set up to provide rapid and appropriate serodiagnosis of primitive endemic mycoses, an important cause of morbidity and mortality in an increasingly high number of patients. The mycoarray consists of three antigen extracts (histoplasmin, coccidioidin and Coccidioides "TP") and antibody dilution curves were spotted on microarray slides. The arrays were processed with coccidioidomycosis and histoplasmosis patients? sera or with control sera and the occurring immunocomplexes were detected by indirect immunofluorescence. In agreement with clinical and microbiological diagnosis, the results distinguished between histoplasmosis and coccidioidomycosis patients. In addition, the assay could clearly discriminate between IgM and IgG antibody reactivity. No reactivity was ever observed in the arrays processed with negative control sera. Therefore, this pilot study demonstrates that the "mycoarray" is sensitive and specific enough to discriminate between healthy individuals and patients with histoplasmosis or coccidioidomycosis. Because of miniaturization and multiparametricity, the new assay cuts costs and processing time. Thus, once clinically validated and implemented as a large-scale array, the "mycoarray" will be ready to be applied to the daily clinical practice.     

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.     

Perforation of the Nasal Septum as the First Sign of Histoplasmosis Associated with AIDS and Review of Published Literature

Disseminated histoplasmosis in South America is associated with AIDS in 70–90 % of cases. It is visceral and cutaneous, compromising the oral, pharynx, and laryngeal mucous membranes. The involvement of the nasal mucosa is unusual. Two patients with perforation of the nasal septum as the only sign of their disease were clinically and histopathologically diagnosed as leishmaniasis. The revision of the biopsies and the culture of nasal discharge secretions showed that the pathogens seen were not amastigotes but Histoplasma capsulatum. Other mycotic lesions were not detected, nor there was history of cutaneous leishmaniasis. The leishmanin skin test, available only for the male patient, was negative. The PCR and immunofluorescence antibody titers for Leishmania were negative in both patients. They were HIV positive; in the male, his CD4+ T cell count was 60/mm³ and in the female 133/mm³. The nasal ulcer was the only manifestation of histoplasmosis and the first of AIDS in both patients. The male patient recovered with amphotericin B and itraconazole treatment. The female has improved with itraconazole. Both patients received antiretroviral treatment. Nasal mucous membrane ulcers should include histoplasmosis among the differential diagnosis. In conclusion, two patients had perforation of their nasal septum as the only manifestation of histoplasmosis, a diagnosis confirmed by nasal mucosa biopsy and by culture of H. capsulatum, findings which demonstrated that both patients had AIDS.     

Brote de histoplasmosis en la provincia de Neuquén,Patagonia Argentina

BackgroundIn Argentina, there are no reports of autochthonous cases of histoplasmosis in the southern regions of the country.AimTo report a histoplasmosis outbreak in Zapala town, Province of Neuquén, Patagonia Argentina.MethodsWe evaluated the clinical and epidemiological characteristics of 5 patients involved in the outbreak. Environmental studies were conducted to determine the source of infection. The genetic profile of Histoplasma capsulatum strains isolated from the index case (IC) were compared with clinical isolates from Argentinean patients not related to the outbreak, using RAPD-PCR with primers 1281-1283.ResultsThe patients were residents of Zapala, and had not visited other geographical areas before. All patients had an influenza-like syndrome, and X-ray revealed disseminated micronodular images throughout the lung parenchyma. The IC needed specific antifungal therapy; the remaining 4 patients had mild symptoms, and did not require therapy. All of them had a good clinical outcome. Strains of H. capsulatum isolated from blood culture and lung biopsy of the IC showed a genetic profile different from other strains analyzed. The presence of the fungus in the environment was demonstrated by the detection of anti-Histoplasma antibodies in BALB/c mice inoculated with soil obtained in a culvert where workers had dug up earth after a landslide.ConclusionsThis outbreak suggests the histoplasmosis endemic area is under the 38° S parallel. Patients from Neuquén, Patagonia Argentina, with compatible symptoms of histoplasmosis should be tested, regardless of their travel or exposure history.     

A case of disseminated histoplasmosis diagnosed after oral presentation in an old HIV‐negative patient in Sweden

Histoplasmosis is an endemic disease in various regions such as North America and South‐East Asia but remains rare in Europe. Disseminated histoplasmosis is unusual in HIV‐negative patients. Here, we describe a case of disseminated histoplasmosis in an HIV‐negative patient diagnosed after oral presentation.     

Two Specific Strains of <Emphasis Type="Italic">Histoplasma capsulatum</Emphasis> causing Mucocutaneous Manifestations of Histoplasmosis: Preliminary Analysis of a Frequent Manifestation of Histoplasmosis in Southern Brazil

Objectives  Skin lesions, uncommon in US cases (<10%), occur in 38–85% of cases reported from Latin America. Although these differences may reflect reporting bias, delayed diagnosis, or differences in host immune response among different ethnic groups, they also could result from genetic differences changing the pathobiology of the organism. It is possible that genetic differences among strains of H. capsulatum may influence the pathogenesis and clinical manifestations of histoplasmosis. Methods  We examined the clinical features of patients with mucocutaneous manifestations of histoplasmosis and performed genetic analysis based on nucleotide sequence variations in the internal transcribed spacer regions of rRNA genes of H. capsulatum isolates of patients. Two pairs of PCR primers were designed to develop and amplify the ITS regions of H. capsulatum, 5′-TACCCGGCCACCCTTGTCTA-3′ and 5′-AGCGGGTGGCAAAGCCC-3′. These primers were based on the ITS sequence of Ajellomyces capsulatus, the ascomycetous teleomorph form of H. capsulatum, deposited in the GenBank (accession number U18363). Eight patients attending a tertiary-care hospital in southern Brazil were enrolled into the study. All case patients had skin cultures growing H. capsulatum at the mycology laboratory. Results  Six of eight (75%) patients were HIV-positive and presented involvement of multiples organs by H. capsulatum. Two HIV-negative patients did not present evidence of involvement of other organs besides mucosa and skin. ITS sequencing of a DNA H. capsulatum fragment of 485-bp from isolates of 8 patients revealed two distinct strains. The 2 distinct fragments (Hc1, Hc2) differed from each other at 7 positions in the ITS regions. They were identical to strains of H. capsulatum isolated in patients from Colombia and Argentina, but different from strains isolated in US. Hc1 and Hc2 were isolated in 5 patients and 3 patients, respectively, with mucocutaneous manifestations of histoplasmosis. Both Hc1 and Hc2 strains were isolated in HIV-infected and non-HIV-infected patients. Conclusions  Mucocutaneous manifestations of histoplasmosis, which are frequently seen in Brazilian patients were caused by 2 specific strains in our institution. Those strains have been isolated in patients with these particular clinical features of histoplasmosis in Latin America. Our study suggests that unique pathogenic characteristics among the Latin American species of H. capsulatum might explain its increased dermatotropism.