Multicenter case-control study of risk factors for histoplasmosis in human immunodeficiency virus-infected persons

Histoplasma seropositivity and environmental risk factors for exposure in a general population in Upper River Region, The Gambia: A cross-sectional study

Robust surveillance of Histoplasma species is warranted in endemic regions, including investigation of community-level transmission dynamics. This cross-sectional study explored anti-Histoplasma antibody seroprevalence and risk factors for exposure in a general population in Upper River Region (URR), The Gambia. Study participants were recruited (December 2022-March 2023) by random household sampling across 12 Enumeration Areas (EAs) of URR. A questionnaire and clinical examination were performed; exploring demographic, clinical and environmental risk factors for Histoplasma exposure. One venous blood sample per participant was subject to IMMY Latex Agglutination Histoplasma test to determine presence of a recent IgM response to Histoplasma. Seropositivity risk factors were explored by multi-level, multivariable logistic regression analysis. The study population (n = 298) aged 5-83 years, demonstrated a positively skewed age distribution and comprised 55.4% females. An apparent seroprevalence of 18.8% (n = 56/298, 95% CI 14.5-23.7%) was measured using the LAT. A multivariable model demonstrated increased odds of Histoplasma seropositivity amongst female participants (OR = 2.41 95% CI 1.14-5.10); and participants reporting involvement in animal manure management (OR = 4.21 95% CI 1.38-12.90), and management of domestic animals inside the compound at night during the dry season (OR = 10.72 95% CI 2.02-56.83). Increasing age (OR = 0.96 95% CI 0.93-0.98) was associated with decreased odds of seropositivity. Clustering at EA level was responsible for 17.2% of seropositivity variance. The study indicates frequent recent Histoplasma exposure and presents plausible demographic and environmental risk factors for seropositivity. Histoplasma spp. characterisation at this human-animal-environment interface is warranted, to determine public health implications of environmental reservoirs in The Gambia. The study was supported by Wellcome Trust (206,638/Z/17/Z to CES) and a University of Liverpool-funded PhD studentship (to TRC).

Disseminated histoplasmosis and hemophagocytic lymphohistiocytosis in a patient receiving TNF-alpha inhibitor therapy

Histoplasmosis commonly presents as an asymptomatic or self-limited infection in immunocompetent patients, but immunocompromised hosts may present with severe and disseminated disease. Herein, we present a 26-year-old male with history of ulcerative colitis receiving long-term TNF-alpha inhibitor therapy who presented with six months of diarrhea and recently fever and hematochezia. On admission, he was febrile and hypotensive, with initial workup revealing pancytopenia and imaging reporting pulmonary infiltrates, pancolitis, and enlarged mesenteric lymph nodes. Disseminated histoplasmosis was ultimately diagnosed after examination of the colonic biopsy. Bone marrow biopsy was also consistent with the diagnosis of histoplasmosis but also demonstrated hemophagocytic lymphohistiocytosis. The patient was ultimately treated with amphotericin B, intravenous immunoglobulin, etoposide, and corticosteroids.

An Indian lineage of Histoplasma with strong signatures of differentiation and selection

Histoplasma, a genus of dimorphic fungi, is the etiological agent of histoplasmosis, a pulmonary disease widespread across the globe. Whole genome sequencing has revealed that the genus harbors a previously unrecognized diversity of cryptic species. To date, studies have focused on Histoplasma isolates collected in the Americas with little knowledge of the genomic variation from other localities. In this report, we report the existence of a well-differentiated lineage of Histoplasma occurring in the Indian subcontinent. The group is differentiated enough to satisfy the requirements of a phylogenetic species, as it shows extensive genetic differentiation along the whole genome and has little evidence of gene exchange with other Histoplasma species. Next, we leverage this genetic differentiation to identify genetic changes that are unique to this group and that have putatively evolved through rapid positive selection. We found that none of the previously known virulence factors have evolved rapidly in the Indian lineage but find evidence of strong signatures of selection on other alleles potentially involved in clinically-important phenotypes. Our work serves as an example of the importance of correctly identifying species boundaries to understand the extent of selection in the evolution of pathogenic lineages. IMPORTANCE: Whole genome sequencing has revolutionized our understanding of microbial diversity, including human pathogens. In the case of fungal pathogens, a limiting factor in understanding the extent of their genetic diversity has been the lack of systematic sampling. In this piece, we show the results of a collection in the Indian subcontinent of the pathogenic fungus Histoplasma, the causal agent of a systemic mycosis. We find that Indian samples of Histoplasma form a distinct clade which is highly differentiated from other Histoplasma species. We also show that the genome of this lineage shows unique signals of natural selection. This work exemplifies how the combination of a robust sampling along with population genetics, and phylogenetics can reveal the precise genetic changes that differentiate lineages of fungal pathogens.

Treatment and Prevention of Histoplasmosis in Adults Living with HIV

Histoplasmosis causes life-threatening disseminated infection in adult patients living with untreated HIV. Although disease incidence has declined dramatically in countries with access to antiretroviral therapy, histoplasmosis remains prevalent in many resource-limited regions. A high index of suspicion for histoplasmosis should be maintained in the setting of a febrile multisystem illness in severely immunosuppressed patients, particularly in persons with hemophagocytic lymphohistiocytosis. Preferred treatment regimens for initial therapy include liposomal amphotericin B for severe disease, or itraconazole for mild to moderate disease. Subsequently, itraconazole maintenance therapy should be administered for at least one year and then discontinued if CD4 count increases to ≥150 cells/µL. Antiretroviral therapy, which improves outcome when administered together with an antifungal agent, should be instituted immediately, as the risk of triggering Immune Reconstitution Syndrome is low. The major risk factor for relapsed infection is nonadherence. Itraconazole prophylaxis reduces risk for histoplasmosis in patients with CD4 counts <100/µL but is not associated with survival benefit and is primarily reserved for use in outbreaks. Although most patients with histoplasmosis have not had recognized high-risk exposures, avoidance of contact with bird or bat guano or inhalation of aerosolized soil in endemic regions may reduce risk. Adherence to effective antiretroviral therapy is the most important strategy for reducing the incidence of life-threatening histoplasmosis.

Temporal trends of cutaneo-mucous histoplasmosis in persons living with HIV in French Guiana: Early diagnosis defuses South American strain dermotropism

Histoplasmosis is the most frequent opportunistic infection and the first cause of mortality in HIV-infected patients in French Guiana and presumably in much of Latin America. Mucocutaneous lesions of histoplasmosis are considered as rare and late manifestations of the disease. It has been debated whether the greater proportion of cutaneo-mucous presentations in South America relative to the USA was the reflection of Histoplasma strains with increased dermotropism or simply delayed diagnosis and advanced immunosuppression. The objective of this study was to describe the clinical presentation, frequency, prognosis and temporal trends of cutaneomucous histoplasmosis in French Guiana. A retrospective study of patients with AIDS-related disseminated histoplasmosis followed in the three hospitals of French Guiana was performed between 1981 and 2014. Incident cases of histoplasmosis, proved by pathology and/or mycological examinations, were studied. Mucocutaneous histoplasmosis was confirmed by a positive cutaneous or mucosal biopsy. Mucocutaneous lesions were polymorphic. Ninety percent of patients were profoundly immunocompromised patients (CD4<50/mm3) and over 80% were not on antiretroviral treatment. The frequency of mucocutaneous forms and case fatality of disseminated histoplasmosis within one month of antifungal treatment significantly decreased over time (p<0,001). In this South American territory, diagnostic and therapeutic improvements have led to the quasi disappearance of cutaneous manifestations. There may be South American dermotropism in the laboratory but at the bedside early diagnosis seems to be the main parameter explaining the proportion of cutaneomucous presentations in South America relative to the USA.

Histoplasmosis is the most frequent opportunistic infection and the first cause of mortality in HIV-infected patients in French Guiana and presumably in much of Latin America. Mucocutaneous lesions of histoplasmosis are considered as rare and late manifestations of the disease. It has been debated whether the greater proportion of cutaneo-mucous presentations in South America relative to the USA was the reflection of Histoplasma strains with increased dermotropism or simply delayed diagnosis and advanced immunosuppression. The objective of this study was to describe the clinical presentation, frequency, prognosis and temporal trends of cutaneomucous histoplasmosis in French Guiana. A retrospective study of patients with AIDS-related disseminated histoplasmosis followed in the three hospitals of French Guiana was performed between 1981 and 2014. Incident cases of histoplasmosis, proved by pathology and/or mycological examinations, were studied. Mucocutaneous histoplasmosis was confirmed by a positive cutaneous or mucosal biopsy. Ninety percent of patients were profoundly immunocompromised patients (CD4<50/mm3) and over 80% were not on antiretroviral treatment. The frequency of mucocutaneous forms and case fatality of disseminated histoplasmosis within one month of antifungal treatment significantly decreased over time. Hence, in this South American territory, diagnostic and therapeutic improvements have led to the quasi-disappearance of cutaneous manifestations. There may be South American dermotropism in the laboratory but at the bedside early diagnosis seems to be the main parameter explaining the proportion of cutaneomucous presentations in South America relative to the USA.

Enhanced Surveillance for Histoplasmosis-9 States, 2018-2019

Background

Histoplasmosis is often described as the most common endemic mycosis in the United States, but much remains unknown about its epidemiology among the general population.

Methods

We conducted enhanced surveillance in 9 states during 2018-2019 by identifying cases through routine surveillance and interviewing 301 patients about their clinical features and exposures.

Results

Before being tested for histoplasmosis, 60% saw a health care provider ≥3 times, and 53% received antibacterial medication. The median time from seeking health care to diagnosis (range) was 23 (0-269) days. Forty-nine percent were hospitalized, and 69% said that histoplasmosis interfered with their daily activities (median [range], 56 [2-3960] days). Possible exposures included handling plants (48%) and bird or bat droppings (24%); 22% reported no specific exposures. Only 15% had heard of histoplasmosis before their illness.

Conclusions

Histoplasmosis can be severe and prolonged. Additional educational efforts to increase public and provider awareness and reduce delays in diagnosis are needed.

Comparison of Disseminated Histoplasmosis with and without Cutaneo-Mucous Lesions in Persons Living with HIV in French Guiana

Introduction: Histoplasmosis is the main opportunistic infection and cause of death in HIV-infected persons living with HIV in French Guiana and probably in most of Latin America. The objective of the present study was to compare cutaneomucous histoplasmosis to non-cutaneomucous histoplasmosis in French Guiana. Methods: Between 1981 and 2014 AIDS-related disseminated histoplasmosis patients followed in the three hospitals of French Guiana were retrospectively studied. Only proven incident cases of histoplasmosis, either by pathology and/or mycological analysis, were considered. Mucocutaneous histoplasmosis was ascertained by a positive mucosal or cutaneous biopsy. Results: Thirty-one patients had mucocutaneous lesions, and 318 had no mucocutaneous lesions. Patients with cutaneomucous lesions were more likely to have had prior opportunistic infections (35.5%) than those who did not have cutaneomucous lesions (19.5%). They were more likely to be very severely immunocompromised (CD4 count < 50) (90.3% versus 62.8%) and less likely to have digestive signs (32.3% versus 74.1%) and superficial adenopathies (29% versus 50.2%) than those without cutaneomucous lesions. In terms of simple biological examinations, patients with cutaneomucous lesions had fewer signs of cholestasis. The diagnosis was significantly more likely to be performed by direct examination and pathology in those with cutaneomucous lesions than in those without such lesions. On the contrary, patients with cutaneomucous lesions were less likely to be diagnosed by fungal culture than those without cutaneomucous lesions. There was a greater but non-significant risk of early death in those with cutaneomucous lesions relative to those without (OR = 2.28 (95%CI = 0.83–5.7), p = 0.056. Conclusions: Mucocutaneous forms were associated with more profound immunosuppression and perhaps risk of early death. They are easily accessible for diagnosis.

Treating progressive disseminated histoplasmosis in people living with HIV

BACKGROUND

Progressive disseminated histoplasmosis (PDH) is a serious fungal infection that affects people living with HIV. The best way to treat the condition is unclear.

OBJECTIVES

We assessed evidence in three areas of equipoise. 1. Induction. To compare efficacy and safety of initial therapy with liposomal amphotericin B versus initial therapy with alternative antifungals. 2. Maintenance. To compare efficacy and safety of maintenance therapy with 12 months of oral antifungal treatment with shorter durations of maintenance therapy. 3. Antiretroviral therapy (ART). To compare the outcomes of early initiation versus delayed initiation of ART.

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; Cochrane CENTRAL; MEDLINE (PubMed); Embase (Ovid); Science Citation Index Expanded, Conference Proceedings Citation Index-Science, and BIOSIS Previews (all three in the Web of Science); the WHO International Clinical Trials Registry Platform, ClinicalTrials.gov, and the ISRCTN registry, all up to 20 March 2020.

SELECTION CRITERIA

We evaluated studies assessing the use of liposomal amphotericin B and alternative antifungals for induction therapy; studies assessing the duration of antifungals for maintenance therapy; and studies assessing the timing of ART. We included randomized controlled trials (RCT), single-arm trials, prospective cohort studies, and single-arm cohort studies.

DATA COLLECTION AND ANALYSIS

Two review authors assessed eligibility and risk of bias, extracted data, and assessed certainty of evidence. We used the Cochrane 'Risk of bias' tool to assess risk of bias in randomized studies, and ROBINS-I tool to assess risk of bias in non-randomized studies. We summarized dichotomous outcomes using risk ratios (RRs), with 95% confidence intervals (CI).

MAIN RESULTS

We identified 17 individual studies. We judged eight studies to be at critical risk of bias, and removed these from the analysis. 1. Induction We found one RCT which compared liposomal amphotericin B to deoxycholate amphotericin B. Compared to deoxycholate amphotericin B, liposomal amphotericin B may have higher clinical success rates (RR 1.46, 95% CI 1.01 to 2.11; 1 study, 80 participants; low-certainty evidence). Compared to deoxycholate amphotericin B, liposomal amphotericin B has lower rates of nephrotoxicity (RR 0.25, 95% CI 0.09 to 0.67; 1 study, 77 participants; high-certainty evidence). We found very low-certainty evidence to inform comparisons between amphotericin B formulations and azoles for induction therapy. 2. Maintenance We found no eligible study that compared less than 12 months of oral antifungal treatment to 12 months or greater for maintenance therapy. For both induction and maintenance, fluconazole performed poorly in comparison to other azoles. 3. ART We found one study, in which one out of seven participants in the 'early' arm and none of the three participants in the 'late' arm died.

AUTHORS' CONCLUSIONS

Liposomal amphotericin B appears to be a better choice compared to deoxycholate amphotericin B for treating PDH in people with HIV; and fluconazole performed poorly compared to other azoles. Other treatment choices for induction, maintenance, and when to start ART have no evidence, or very low certainty evidence. PDH needs prospective comparative trials to help inform clinical decisions.

HIV-Associated Histoplasmosis: Current Perspectives

Histoplasmosis is an endemic mycosis caused by Histoplasma capsulatum. Infection develops by inhalation of microconidia from environmental sites inhabited by birds and bats. Disseminated disease is the usual presentation due to impaired cellular immunity. Common clinical manifestations include fever, fatigue, malaise, anorexia, weight loss, and respiratory symptoms. Histoplasma antigen detection is the most sensitive method for diagnosis. The sensitivity of the MVista^® Quantitative Histoplasma antigen enzyme immunoassay is 95-100% in urine, over 90% in serum and bronchoalveolar lavage (BAL) antigen and 78% in cerebral spinal fluid (CSF). A proven diagnosis can be established by culture or pathology with sensitivities between 70% and 80%. The sensitivity of antibody detection by immunodiffusion or complement fixation was between 60% and 70%. Diagnosis using molecular methods has not been adequately validated for implementation and FDA cleared assays are unavailable. Liposomal amphotericin B should be used for 1-2 weeks followed by itraconazole for at least one year until CD4 counts are above 150 cells/mm3, HIV viral load is below 400 copies/mL and Histoplasma urine antigen is negative. Serum itraconazole level should be monitored to avoid drug toxicity. Antigen should be measured periodically to establish that treatment is effective and to assist in identifying relapse. The incidence of immune reconstitution inflammatory syndrome is low but it must be considered in patients who are thought to be failing antifungal treatment as it does not respond to changing antifungal agents but rather to initiation of corticosteroid therapy. In this review, we discuss pathogenesis, clinical manifestations, diagnosis and treatment based on personal experience and relevant publications.

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.

The Broad Clinical Spectrum of Disseminated Histoplasmosis in HIV-Infected Patients: A 30 Years' Experience in French Guiana

Histoplasmosis is a common but neglected AIDS-defining condition in endemic areas for Histoplasma capsulatum. At the advanced stage of HIV infection, the broad spectrum of clinical features may mimic other frequent opportunistic infections such as tuberculosis and makes it difficult for clinicians to diagnose histoplasmosis in a timely manner. Diagnosis of histoplasmosis is difficult and relies on a high index of clinical suspicion along with access to medical mycology facilities with the capacity to implement conventional diagnostic methods (direct examination and culture) in a biosafety level 3 laboratory as well as indirect diagnostic methods (molecular biology, antibody, and antigen detection tools in tissue and body fluids). Time to initiation of effective antifungals has an impact on the patient's prognosis. The initiation of empirical antifungal treatment should be considered in endemic areas for Histoplasma capsulatum and HIV. Here, we report on 30 years of experience in managing HIV-associated histoplasmosis based on a synthesis of clinical findings in French Guiana with considerations regarding the difficulties in determining its differential diagnosis with other opportunistic infections.

An Italian Case of Disseminated Histoplasmosis Associated with HIV

Histoplasma capsulatum is a dimorphic fungus, endemic in the Americas, Africa (var. duboisii), India, and Southeast Asia. H. capsulatum infection is rarely diagnosed in Italy, while in Latin America, progressive disseminated histoplasmosis (PDH) is one of the most frequent AIDS-defining illnesses and causes of AIDS-related deaths. We report a case of PDH and new HIV infection diagnosis in a Cuban patient, who has been living in Italy for the past 10 years. Bone marrow aspirate and peripheral blood smear microscopy suggested H. capsulatum infection. The diagnosis was confirmed with the culture method identifying its thermal dimorphism. Liposomal amphotericin B was administered alone for 10 days and then for another 2 days, accompanied with voriconazole; the former was stopped for probable side effects (persistent fever and worsening thrombocytopenia), and voriconazole was continued to complete 4 weeks. PDH maintenance treatment consisted of itraconazole for one year. Antiretroviral therapy (ART) was started on the third week of antifungal treatment. At the 3-year follow-up, the patient is adherent on ART, the virus was suppressed, and she has an optimal immune recovery. This case highlights the need to suspect histoplasmosis in the differential diagnosis of opportunistic infections in immunocompromised persons, native to or who have traveled to endemic countries.

Loop-mediated Isothermal Amplification and nested PCR of the Internal Transcribed Spacer (ITS) for Histoplasma capsulatum detection

Background

Histoplasmosis is a neglected disease that affects mainly immunocompromised patients, presenting a progressive dissemination pattern and a high mortality rate, mainly due to delayed diagnosis, caused by slow fungal growth in culture. Therefore, a fast, suitable and cost-effective assay is required for the diagnosis of histoplasmosis in resource-limited laboratories. This study aimed to develop and evaluate two new molecular approaches for a more cost-effective diagnosis of histoplasmosis.

Methodology

Seeking a fast, suitable, sensitive, specific and low-cost molecular detection technique, we developed a new Loop-mediated Isothermal Amplification (LAMP) assay and nested PCR, both targeting the Internal Transcribed Spacer (ITS) multicopy region of Histoplasma capsulatum. The sensitivity was evaluated using 26 bone marrow and 1 whole blood specimens from patients suspected to have histoplasmosis and 5 whole blood samples from healthy subjects. All specimens were evaluated in culture, as a reference standard test, and Hcp100 nPCR, as a molecular reference test. A heparin-containing whole blood sample from a heathy subject was spiked with H. capsulatum cells and directly assayed with no previous DNA extraction.

Results

Both assays were able to detect down to 1 fg/μL of H. capsulatum DNA, and ITS LAMP results could also be revealed to the naked-eye by adding SYBR green to the reaction tube. In addition, both assays were able to detect all clades of Histoplasma capsulatum cryptic species complex. No cross-reaction with other fungal pathogens was presented. In comparison with Hcp100 nPCR, both assays reached 83% sensitivity and 92% specificity. Furthermore, ITS LAMP assay showed no need for DNA extraction, since it could be directly applied to crude whole blood specimens, with a limit of detection of 10 yeasts/μL.

Conclusion

ITS LAMP and nPCR assays have the potential to be used in conjunction with culture for early diagnosis of progressive disseminated histoplasmosis, allowing earlier, appropriate treatment of the patient. The possibility of applying ITS LAMP, as a direct assay, with no DNA extraction and purification steps, makes it suitable for resource-limited laboratories. However, more studies are necessary to validate ITS LAMP and nPCR as direct assay in other types of clinical specimens.

Histoplasmosis is a worldwide neglected disease with a high mortality rate associated with HIV/AIDS patients, killing more than tuberculosis in some endemic countries in Latin America. Part of this elevated mortality rate is due to delayed diagnosis and treatment. Here we present two novel methods, one based on Loop-mediated Isothermal Amplification (LAMP) and another on nested Polymerase Chain Reaction (nPCR), for fast, sensitive and specific diagnosis of histoplasmosis. Tests of blood samples spiked with Histoplasma capsulatum suggest the possibility of direct application of the LAMP assay proposed herein to clinical specimens without the need for previous DNA extraction and with the added advantage of naked-eye evaluation of the reaction results. Once the assay has been validated in different clinical specimens, it may be a promising tool for fast histoplasmosis screening.

Multistate Epidemiology of Histoplasmosis, United States, 2011-2014

Increased awareness could lead to appropriate diagnosis, prompt treatment, and better patient outcomes.

Histoplasmosis is one of the most common mycoses endemic to the United States, but it was reportable in only 10 states during 2016, when a national case definition was approved. To better characterize the epidemiologic features of histoplasmosis, we analyzed deidentified surveillance data for 2011–2014 from the following 12 states: Alabama, Arkansas, Delaware, Illinois, Indiana, Kentucky, Michigan, Minnesota, Mississippi, Nebraska, Pennsylvania, and Wisconsin. We examined epidemiologic and laboratory features and calculated state-specific annual and county-specific mean annual incidence rates. A total of 3,409 cases were reported. Median patient age was 49 (interquartile range 33–61) years, 2,079 (61%) patients were male, 1,273 (57%) patients were hospitalized, and 76 (7%) patients died. Incidence rates varied markedly between and within states. The high hospitalization rate suggests that histoplasmosis surveillance underestimates the true number of cases. Improved surveillance standardization and surveillance by additional states would provide more comprehensive knowledge of histoplasmosis in the United States.

Histoplasma Peritonitis: An Extremely Rare Complication of Peritoneal Dialysis

Bacterial peritonitis is a common complication of peritoneal dialysis, but fungal peritonitis is unusual and is mostly due to Candida species. Peritonitis due to Histoplasma capsulatum is rare and we report one such case. A 63-year-old female presented with progressively worsening abdominal pain, fever, and altered mental status. She had end-stage renal disease and had been on peritoneal dialysis for 4 years. She had abdominal tenderness without rebound or guarding. Laboratory studies and CT of abdomen were significant for leukocytosis and peritoneal membrane thickening, respectively. Peritoneal dialysis fluid study was consistent with peritonitis and culture of the fluid grew Histoplasma capsulatum. Treatment recommendations include removal of catheter and initiation of antifungal therapy. With the availability of newer antifungals, medical management without removal of PD catheter is possible, but at the same time if there is no response to treatment within a week, PD catheter should be removed promptly.

Histoplasmosis in Africa: An emerging or a neglected disease?

Histoplasmosis in Africa has markedly increased since the advent of the HIV/AIDS epidemic but is under-recognised. Pulmonary histoplasmosis may be misdiagnosed as tuberculosis (TB). In the last six decades (1952-2017), 470 cases of histoplasmosis have been reported. HIV-infected patients accounted for 38% (178) of the cases. West Africa had the highest number of recorded cases with 179; the majority (162 cases) were caused by Histoplasma capsulatum var. dubuosii (Hcd). From the Southern African region, 150 cases have been reported, and the majority (119) were caused by H. capsulatum var. capsulatum (Hcc). There have been 12 histoplasmin skin test surveys with rates of 0% to 35% positivity. Most cases of Hcd presented as localised lesions in immunocompetent persons; however, it was disseminated in AIDS patients. Rapid diagnosis of histoplasmosis in Africa is only currently possible using microscopy; antigen testing and PCR are not available in most of Africa. Treatment requires amphotericin B and itraconazole, both of which are not licensed or available in several parts of Africa.

Opportunistic Invasive Mycoses in AIDS: Cryptococcosis, Histoplasmosis, Coccidiodomycosis, and Talaromycosis

PURPOSE OF REVIEW

The goal of this review is to provide an update on the epidemiology, diagnosis, and treatment of opportunistic fungal infections in patients with human immunodeficiency virus (HIV) infection including Cryptococcus spp., Histoplasma spp., Coccidioides spp., and Talaromyces marneffei, formerly Penicillium marneffei.

RECENT FINDINGS

In many settings, despite increasing roll out of antiretroviral therapy (ART), opportunistic invasive mycoses produce a substantial burden of disease. The prevalence of specific fungal pathogens depends on their endemicity. Viral suppression achieved by greater access to ART and increased the availability of point-of-care testing with rapid diagnostic tests (RDTs) aid to curtail the associated fungi morbidity. RDTs allow earlier screening to preemptively initiate treatment of opportunistic fungal pathogens. Identifying asymptomatic cryptococcal infection before starting ART is crucial in reducing the risk of the immune reconstitution inflammatory syndrome (IRIS). There is an urgent need to decrease the burden of opportunistic invasive fungal infections in individuals with HIV/AIDS through different interventions: (a) continue to expand the deployment of ART to the most affected populations to achieve viral suppression; (b) ensure early diagnosis of fungal pathogen with point-of-care testing;

High Mortality and Coinfection in a Prospective Cohort of Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome Patients with Histoplasmosis in Guatemala

Histoplasmosis is one of the most common and deadly opportunistic infections among persons living with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome in Latin America, but due to limited diagnostic capacity in this region, few data on the burden and clinical characteristics of this disease exist. Between 2005 and 2009, we enrolled patients ≥ 18 years of age with suspected histoplasmosis at a hospital-based HIV clinic in Guatemala City. A case of suspected histoplasmosis was defined as a person presenting with at least three of five clinical or radiologic criteria. A confirmed case of histoplasmosis was defined as a person with a positive culture or urine antigen test for Histoplasma capsulatum. Demographic and clinical data were also collected and analyzed. Of 263 enrolled as suspected cases of histoplasmosis, 101 (38.4%) were confirmed cases. Median time to diagnosis was 15 days after presentation (interquartile range [IQR] = 5-23). Crude overall mortality was 43.6%; median survival time was 19 days (IQR = 4-69). Mycobacterial infection was diagnosed in 70 (26.6%) cases; 26 (25.7%) histoplasmosis cases were coinfected with mycobacteria. High mortality and short survival time after initial symptoms were observed in patients with histoplasmosis. Mycobacterial coinfection diagnoses were frequent, highlighting the importance of pursuing diagnoses for both diseases.

Fungal infections in HIV/AIDS

Fungi are major contributors to the opportunistic infections that affect patients with HIV/AIDS. Systemic infections are mainly with Pneumocystis jirovecii (pneumocystosis), Cryptococcus neoformans (cryptococcosis), Histoplasma capsulatum (histoplasmosis), and Talaromyces (Penicillium) marneffei (talaromycosis). The incidence of systemic fungal infections has decreased in people with HIV in high-income countries because of the widespread availability of antiretroviral drugs and early testing for HIV. However, in many areas with high HIV prevalence, patients present to care with advanced HIV infection and with a low CD4 cell count or re-present with persistent low CD4 cell counts because of poor adherence, resistance to antiretroviral drugs, or both. Affordable, rapid point-of-care diagnostic tests (as have been developed for cryptococcosis) are urgently needed for pneumocystosis, talaromycosis, and histoplasmosis. Additionally, antifungal drugs, including amphotericin B, liposomal amphotericin B, and flucytosine, need to be much more widely available. Such measures, together with continued international efforts in education and training in the management of fungal disease, have the potential to improve patient outcomes substantially.

Clinical and Laboratory Profile of Persons Living with Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome and Histoplasmosis from a Colombian Hospital

Histoplasmosis is common among persons living with human immunodeficiency virus/acquired immune deficiency syndrome (PLWHA) in Latin America, but its diagnosis is difficult and often nonspecific. We conducted prospective screening for histoplasmosis among PLWHA with signs or symptoms suggesting progressive disseminated histoplasmosis (PDH) and hospitalized in Hospital La María in Medellín, Colombia. The study's aim was to obtain a clinical and laboratory profile of PLWHA with PDH. During 3 years (May 2008 to August 2011), we identified 89 PLWHA hospitalized with symptoms suggestive of PDH, of whom 45 (51%) had histoplasmosis. We observed tuberculosis (TB) coinfection in a large proportion of patients with PDH (35%), so all analyses were performed adjusting for this coinfection and, alternatively, excluding histoplasmosis patients with TB. Results showed that the patients with PDH were more likely to have Karnofsky score ≤ 30 (prevalence ratio [PR] = 1.98, 95% confidence interval [CI] = 0.97-4.06), liver compromised with hepatomegaly and/or splenomegaly (PR = 1.77, CI = 1.03-3.06) and elevation in serum of alanine aminotransferase and aspartate aminotransferase to values > 40 mU/mL (PR = 2.06, CI = 1.09-3.88 and PR = 1.53, CI = 0.99-2.35, respectively). Using multiple correspondence analyses, we identified in patients with PDH a profile characterized by the presence of constitutional symptoms, namely weight loss and Karnofsky classification ≤ 30, gastrointestinal manifestations with alteration of liver enzymes and hepatosplenomegaly and/or splenomegaly, skin lesions, and hematological alterations. Study of the profiles is no substitute for laboratory diagnostics, but identifying clinical and laboratory indicators of PLWHA with PDH should allow development of strategies for reducing the time to diagnosis and thus mortality caused by Histoplasma capsulatum.

Histoplasmosis infections worldwide: thinking outside of the Ohio River valley

In the United States, histoplasmosis is generally thought to occur mainly in the Ohio and Mississippi River Valleys, and the classic map of histoplasmosis distribution reflecting this is second nature to many U.S. physicians. With the advent of the HIV pandemic reports of patients with progressive disseminated histoplasmosis and AIDS came from regions of known endemicity, as well as from regions not thought to be endemic for histoplasmosis throughout the world. In addition, our expanding armamentarium of immunosuppressive medications and biologics has increased the diagnosis of histoplasmosis worldwide. While our knowledge of areas in which histoplasmosis is endemic has improved, it is still incomplete. Our contention is that physicians should consider histoplasmosis with the right constellations of symptoms in any febrile patient with immune suppression, regardless of geographic location or travel history.

Histoplasmosis in HIV-Infected Patients: A Review of New Developments and Remaining Gaps

Histoplasma capsulatum is responsible for histoplasmosis, a fungal disease with worldwide distribution that can affect both immunocompromised and imunocompetent individuals. During the highly active antiretroviral therapy (HAART) era, morbidity and mortality due to histoplasmosis remained a public heatlh problem in low-income and high-income countries. The true burden of HIV-associated histoplasmosis is either not fully known or neglected since it is not a notifiable disease. Progress has been made in DNA patterns of strains and understanding of pathogenesis, and hopefully these will help identify new therapeutic targets. Unfortunately, histoplasmosis is still widely mistaken for multidrug-resistant tuberculosis, leading to numerous avoidable deaths, even if they are easily distinguishable. The new diagnostic tools and therapeutics developments have still not been made available in most endemic regions. Still, recent developments are promising because of their good clinical characteristics and also because they will be commercially available and affordable. This review of published data and gaps may help define and guide future research.

Progressive disseminated histoplasmosis in the HIV population in Europe in the HAART era. Case report and literature review

INTRODUCTION

In highly endemic areas, up to 20 % of human immunodeficiency virus (HIV)-infected persons will develop progressive disseminated histoplasmosis (PDH). Europe is not endemic to histoplasmosis, and the disease is mainly found in immigrants often co-infected with HIV.

METHODS

We present a case of a patient with HIV and PDH highlighting the possible diagnostic difficulties that may arise in a non-endemic area and review the literature of histoplasmosis in the context of HIV infection with special focus on Europe.

DISCUSSION

When cellular immunity wanes (usually at CD4 T-lymphocyte counts <150 cells/μL) histoplasma infection, acquired earlier, can reactivate and disseminate. PDH is an acquired immune deficiency syndrome(AIDS)-defining disease and a life-threatening infection, with a clinical spectrum ranging from an acute, fatal course with lung infiltrates and respiratory failure, shock, coagulopathy and multi-organ failure, to a more subacute disease with focal organ involvement, pancytopenia and hepatosplenomegaly. Mortality rates remain high for untreated patients, but early diagnosis, proper antifungal treatment and early initiation of antiretroviral therapy have improved the prognosis.

CONCLUSION

European infectious diseases physicians, microbiologists and pathologists must be aware of histoplasmosis, particularly when facing HIV-infected immigrants from endemic areas. This is increasingly important due to migration and travel activities from these areas.

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.

Disseminated histoplasmosis is the first AIDS-related disease in French Guiana, and probably in the Amazonian area. In order to determine the factors that are associated with histoplasmosis, a retrospective looked at a cohort of HIV-infected patients between 1996 and 2008. Multiple models were used to study the relation of age, sex, last CD4/CD8 count, CD4 nadir, herpes or pneumocystosis, cotrimoxazole and fluconazole use, antiretroviral treatment and the notion of recent initiation of antiretroviral treatment with the occurrence of disseminated histoplasmosis. A total of 1404 patients were followed for 6833 person-years. The variables independently associated with the incidence of disseminated histoplasmosis were low CD4 counts, the lowest CD4 counts were most at risk; Patients with the lowest CD8 counts were also at increased risk; Antiretroviral treatment was generally associated with lower histoplasmosis incidence, but for the first 6 months following antiretroviral treatment initiation there was a transient period of increased risk of diagnosing histoplasmosis; Herpes was also associated with more histoplasmosis; Pneumocystosis and Fluconazole treatment were negatively associated with histoplasmosis. Of 156 patients with histoplasmosis, 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 low CD4 counts and no 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. These results are useful to guide clinicians working in an area where this diagnosis is often overlooked.

Diagnostic value of culture and serological tests in the diagnosis of histoplasmosis in HIV and non-HIV Colombian patients

We determined the value of culture and serological tests used to diagnose histoplasmosis. The medical records of 391 histoplasmosis patients were analyzed. Diagnosis of the mycosis was assessed by culture, complement fixation, and immunodiffusion tests; 310 patients (79.5%) were male, and 184 patients (47.1%) were infected with human immunodeficiency virus (HIV). Positivity value for cultures was 35.7% (74/207), reactivity of serological tests was 95.2% (160/168), and a combination of both methodologies was 16.9% (35/207) for non-HIV patients. Positivity value for cultures was 75.0% (138/184), reactivity of serological tests was 92.4% (85/92), and a combination of both methodologies was 26.0% (48/184) for HIV/acquired immunodeficiency syndrome (AIDS) patients; 48.1% (102/212) of extrapulmonary samples from HIV/AIDS patients yielded positive cultures compared with 23.1% (49/212) in non-HIV patients. Lymphocyte counts made for 33.1% (61/184) of HIV/AIDS patients showed a trend to low CD4+ numbers and higher proportion of positive cultures. These results indicate that culture is the most reliable fungal diagnostic method for HIV/AIDS patients, and contrary to what is generally believed, serological assays are useful for diagnosing histoplasmosis in these patients.

Histoplasmosis: a new endemic fungal infection in China? Review and analysis of cases

Histoplasmosis occurs in specific endemic areas, including the mid-western United States, Africa and most of Latin America. Sporadic cases have also been reported in China. The aim of this study was to summarise the epidemiological and clinical data of histoplasmosis in China. We searched the PubMed, CBMdisk and CNKI databases to identify publications related to histoplasmosis in China. Case reports/series on patients with histoplasmosis were included. A comprehensive literature review identified additional cases. The relevant material was evaluated and reviewed. Overall, 300 cases of histoplasmosis were reported in China from 1990 to 2011, and 75% were from regions through which the Yangtze River flows. Most of the patients were autochthonous infections. Of these, 43 patients had pulmonary histoplasmosis and 257 patients had disseminated histoplasmosis. Common underlying diseases included HIV infection, diabetes mellitus and liver diseases. Fever was the most frequently reported clinical feature in disseminated histoplasmosis, followed by splenomegaly and hepatomegaly. Cases of histoplasmosis had a prominent geographical distribution in China. Histoplasmosis should be considered in the diagnosis of patients with relevant symptoms and a history of travel to or residence in these areas.

Imported acquired immunodeficiency syndrome-related histoplasmosis in metropolitan France: a comparison of pre-highly active anti-retroviral therapy and highly active anti-retroviral therapy eras

Histoplasma capsulatum var. capsulatum infection is rare outside disease-endemic areas. Clinical presentation and outcome of acquired immunodeficiency syndrome-related histoplasmosis are unknown in non-endemic areas with wide access to highly active anti-retroviral therapy (HAART). Retrospective analysis of cases recorded at the French National Reference Center for Mycoses and Antifungals during two decades: pre-HAART (1985-1994) and HAART (1997-2006). Clinical features and outcome of all adults with proven acquired immunodeficiency syndrome-related histoplasmosis were compared between the two periods. One hundred four patients were included (40 during the pre-HAART era and 64 during the HAART era). Diagnosis was established a mean of 62 days after onset of symptoms. One-year overall mortality rates decreased from 53% (pre-HAART era) to 22% (HAART era). Diagnosis during the pre-HAART era and an older age were the only independent factors associated with death. Histoplasmosis is a rare invasive fungal infection outside disease-endemic areas. Its prognosis improved significantly during the HAART era.

[Clinical and evolutionary characteristics of 134 patients with disseminated histoplasmosis associated with AIDS in the State of Ceará]

INTRODUCTION

Since the beginning of the HIV epidemic in Ceará, disseminated histoplasmosis (DH) has often been detected among AIDS patients.

METHODS

In order to investigate the clinical and laboratory characteristics, evolution and survival of cases of DH/AIDS coinfection, the medical records on 134 cases of DH admitted to a reference hospital in Ceará between 1999 and 2005 were analyzed.

RESULTS

Patients with DH presented higher frequency of daily fever, coughing, weight loss, enlarged liver and spleen and acute kidney failure. The diagnosis was made using investigation and/or cultures. At admission, the following were risk factors for death among DH patients: vomiting, dyspnea, respiratory failure, acute kidney failure, hemoglobin < or = 8g/l, urea > or = 40mg/dl and creatinine > or = 1.5 mg/dl.

CONCLUSIONS

Patients with DH characteristically presented higher fever, previous hospitalization due to respiratory infection and more clinical complications. Significant anemia and elevated urea were independent risk factors for death among DH patients.

Epidemiology of invasive mycoses in North America

The incidence of invasive mycoses is increasing, especially among patients who are immunocompromised or hospitalized with serious underlying diseases. Such infections may be broken into two broad categories: opportunistic and endemic. The most important agents of the opportunistic mycoses are Candida spp., Cryptococcus neoformans, Pneumocystis jirovecii, and Aspergillus spp. (although the list of potential pathogens is ever expanding); while the most commonly encountered endemic mycoses are due to Histoplasma capsulatum, Coccidioides immitis/posadasii, and Blastomyces dermatitidis. This review discusses the epidemiologic profiles of these invasive mycoses in North America, as well as risk factors for infection, and the pathogens' antifungal susceptibility.

Two specific strains of Histoplasma capsulatum 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.

AIDS-related Histoplasma capsulatum var. capsulatum infection: 25 years experience of French Guiana

OBJECTIVE

Histoplasma capsulatum var. capsulatum infection is a major AIDS-defining illness in French Guiana. Although it affects South and Central American countries, the number of published cases is low. We present the largest series of AIDS-related histoplasmosis. The aim of this work is to describe clinical features and to help optimize investigations in settings where antigen detection methods are not available.

DESIGN

Two hundred cases of AIDS-related histoplasmosis, diagnosed in the hospitals of French Guiana, were included retrospectively between 1982 and 2007.

RESULTS

At the time of diagnosis, 92% of patients did not receive highly active antiretroviral therapy. CD4 cell count was less than 100 cells/microl for 80% of them. Most patients had fever, lymphadenopathies, and pulmonary and digestive symptoms. Neurological signs and skin/mucosal locations were less common. Other opportunistic infections were associated in 36.6% of cases (mostly tuberculosis). In most of the patients, lactic dehydrogenase was at least four times the normal value, and there was a moderate increase of aspartate aminotransaminase but not alanine aminotransaminase levels. Bone marrow aspirations were useful, but cultures of liver and lymphadenopathy specimens were the most contributive. Following treatment initiation, 17.5% died within a month. Presumptive treatment was started before diagnostic confirmation in 14.3% of the cases.

CONCLUSION

In high prevalence settings, histoplasmosis often revealed AIDS in severely immunodeficient and poorly followed patients. In the absence of a quick sensitive technique, skin smear and fungal tissue cultures are contributive. Nevertheless, given the diagnostic delays and the poor prognosis, presumptive treatment with amphotericin B-containing regimens should be recommended when clinical and epidemiological contexts are evocative.

A monoclonal antibody to Histoplasma capsulatum alters the intracellular fate of the fungus in murine macrophages

Monoclonal antibodies (MAbs) to a cell surface histone on Histoplasma capsulatum modify murine infection and decrease the growth of H. capsulatum within macrophages. Without the MAbs, H. capsulatum survives within macrophages by modifying the intraphagosomal environment. In the present study, we aimed to analyze the affects of a MAb on macrophage phagosomes. Using transmission electron and fluorescence microscopy, we showed that phagosome activation and maturation are significantly greater when H. capsulatum yeast are opsonized with MAb. The MAb reduced the ability of the organism to regulate the phagosomal pH. Additionally, increased antigen processing and reduced negative costimulation occur in macrophages that phagocytose yeast cells opsonized with MAb, resulting in more-efficient T-cell activation. The MAb alters the intracellular fate of H. capsulatum by affecting the ability of the fungus to regulate the milieu of the phagosome.

Clinical and laboratory features of disseminated histoplasmosis in HIV patients from Brazil

OBJECTIVES

To identify the main clinical and laboratory features of disseminated histoplasmosis (DH) in human immunodeficiency virus (HIV) patients and compare them with those of HIV patients with other opportunistic diseases.

METHODS

Retrospective study of HIV patients comparing the clinical and laboratory data of patients with and without DH. Univariate and multivariate analyses were performed to verify the risk factors related to DH.

RESULTS

In total, 378 HIV patients were included, 164 with DH and 214 with other opportunistic diseases. Acute renal failure, respiratory insufficiency and septic shock were more frequent in DH patients, who also had a higher mortality (32%vs. 14%, P < 0.001). Independent risk factors for DH were: acute renal failure [odds ratio (OR) 5.2; 95% confidence interval (CI) 3.2-8.5; P < 0.001], splenomegaly (OR 3.4; 95% CI 1.19-9.9; P < 0.001), respiratory insufficiency (OR 2.7 95% CI 1.5-5.0; P < 0.001), proteinuria (OR 2.7; 95% CI 1.3-5.2; P = 0.03), hypotension (OR 2.5; 95% CI 1.2-5.0; P = 0.008), hepatomegaly (OR 2.4; 95% CI 1.2-4.8; P = 0.01), cutaneous lesions (OR, 1.9; 95% CI 1.0-3.3; P = 0.02) and weight loss (OR 1.8; 95% CI 1.0-3.1; P = 0.03).

CONCLUSION

Our results suggest that DH is a severe opportunistic disease with high mortality rate, which should be promptly recognized in order to provide early specific treatment.

Mucocutaneous manifestations of disseminated histoplasmosis in patients with acquired immunodeficiency syndrome: particular aspects in a Latin-American population

BACKGROUND

Mucocutaneous lesions in human immunodeficiency virus (HIV)-infected patients with disseminated histoplasmosis have a wide spectrum of clinical manifestations, making its diagnosis difficult. Studies have been restricted to case reports and series with small numbers of patients not specifically focusing on the dermatological aspects of histoplasmosis.

AIMS

To describe the characteristics of mucocutaneous lesions of disseminated histoplasmosis in HIV-infected patients.

METHODS

A retrospective and prospective study was conducted on 36 HIV-infected patients with mucocutaneous histoplasmosis in a tertiary-care hospital in Brazil.

RESULTS

Mucocutaneous histoplasmosis was diagnosed by histopathology in 33 of the 36 patients (91%) and/or culture in 23 (64%). Their CD4+ cell counts ranged from 2 to 103 cells/mm(3). The average number of different morphological types of lesions was three per patient. Despite the variability of the lesions, papules (50%), crusted papules (64%) and oral mucosal erosions and/or ulcers (58%) were the most frequent dermatological lesions. A diffuse pattern of distribution of the skin lesions was found in 58% of the cases. There was significant association between the CD4+ cell counts and the morphological variability of lesions per patient. Variation in the lesions seemed to be associated with higher CD4+ cell counts.

CONCLUSION

Doctors caring for HIV-infected patients should be aware of the wide spectrum of dermatological lesions observed in disseminated histoplasmosis and the importance of detecting and isolating the fungus in mucocutaneous tissues.

Systemic histoplasmosis: a 15-year retrospective institutional review of 111 patients

To our knowledge, an institutional review of systemic histoplasmosis has not been conducted in the United States since the major outbreaks in Indianapolis in 1978-4982. We conducted a retrospective review of all patients with systemic histoplasmosis diagnosed at Mayo Clinic over a 15-year period. The case definitions employed were based on an international consensus statement by the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group (EORTC/IFICG) and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (MSG). One hundred eleven patients with systemic histoplasmosis were identified between January 1, 1991, and December 31, 2005. Of these, 78 patients had disseminated histoplasmosis and 55 patients had Histoplasma capsulatum fungemia. The mean age of patients was 55 years, 66% were male, and 98% were white. Fifty-nine percent of patients were immunocompromised. Fever was the most frequently reported symptom (63%), followed by respiratory complaints (43%) and weight loss (37%). The peripheral white blood cell count was <3000 cells/mm in 28%, hemoglobin was <10 g/dL in 29%, and platelet count was <150,000 cells/mm in 41% of patients. Liver enzymes were elevated (alanine aminotransferase >60 U/L in 39%, aspartate aminotransferase >60 U/L in 27%), alkaline phosphatase was >200 U/L in 55%, and albumin was <3.5 g/dL in 70%. Serologic and histopathologic examinations were each positive in 75% of cases, Histoplasma urine antigen screening was positive in 80%, and H. capsulatum was culture positive in 84%. Forty-seven percent of patients were sequentially treated with an amphotericin B-containing product followed by itraconazole, 31% received itraconazole alone, and 7% received an amphotericin B-containing product only. Another 13% of patients did not receive antifungal treatment, and the remaining 2% did not have treatment data available. Sixty percent of patients required hospitalization, and in hospital mortality was 6% with a median survival time of 61 days. The relapse rate was 9%, with a median relapse-free survival of 857 days. Systemic histoplasmosis should be suspected in patients who have lived in endemic areas with fever, bone marrow suppression, and elevated hepatic enzymes, particularly if they are immunocompromised. Evaluation including a combination of Histoplasma serologic screening, urine antigen assay, and fungal culture will secure the diagnosis in most cases.

Production and evaluation of reagents for detection of Histoplasma capsulatum antigenuria by enzyme immunoassay

The detection of urinary Histoplasma capsulatum polysaccharide antigen (HPA) by enzyme immunoassay (EIA) has proven useful for the presumptive diagnosis of histoplasmosis in AIDS patients. Assay limitations include (i) detection of a largely uncharacterized antigen and (ii) difficulty in reproducibly generating antibodies for use in the EIA. To improve antibody production for use in this test and to better understand the antigen being detected, we compared rabbit antibodies elicited using various immunization schedules, routes, and H. capsulatum-derived antigens. Antibodies were evaluated by EIA for their ability to detect purified H. capsulatum C antigen (C-Ag) and antigenuria. Reported as enzyme immunoassay (EI) units (the A(450) with antigen divided by the A(450) without antigen), results demonstrated that intravenous immunization of rabbits with whole, killed yeast-phase cells (yeast-i.v. regimen) produced antibodies giving the highest EI values in the C-Ag EIA (mean EI units +/- standard deviation, 14.9 +/- 0.6 versus 6.4 +/- 0.4 for rabbits immunized with C-Ag versus 2.4 +/- 0.3 for all other regimens combined). Yeast-i.v. antibodies were highly sensitive for the detection of antigenuria in patients with histoplasmosis, as shown by the following results: 12/12 patients compared to 10/12, 6/12, 3/12, and 3/12, respectively, for antibodies from rabbits immunized with (i) C-Ag; (ii) whole, killed yeast-phase cells administered subcutaneously and intramuscularly; (iii) yeast-phase culture filtrates; and (iv) HPA-positive urine. Rabbits immunized using the yeast-i.v. regimen also gave higher peak antibody titers than rabbits immunized by any other regimen (P < 0.03), and their antibodies were most comparable in reactivity to antibodies produced for use in the standard HPA-EIA test (P < 0.001). Therefore, rabbits immunized using the yeast-i.v. regimen produced the most sensitive antibodies with the highest titers for detection of C-Ag and antigenuria in histoplasmosis patients.

American histoplasmosis in developing countries with a special focus on patients with HIV: diagnosis, treatment, and prognosis

PURPOSE OF REVIEW

Histoplasmosis due to Histoplasma capsulatum var capsulatum is a frequent systemic fungal infection in the Americas. Diagnostic and therapeutic options differ between North and South America. Disseminated histoplasmosis is an AIDS-defining infection. Prognostic factors of potentially severe presentations must be evaluated in order to facilitate the initial therapeutic choice.

RECENT FINDINGS

Patients with HIV with disseminated infections presenting with severe pulmonary and renal impairment have a poor prognosis. Cutaneous presentations are more frequent in HIV patients in South America than in North America. A murine model has shown that South American isolates have a greater virulence that North American isolates. These differences are due in part to diagnostic delays in resource-poor countries.

SUMMARY

Direct examination of May-Grünwald-Giemsa-stained smears or tissues in suspected histoplasmosis is a simple means of confirming the diagnosis in resource-poor settings. Studies of prognostic factors should further refine indication criteria to guide first-line treatment choice between amphotericin B and itraconazole. The association of tuberculosis and histoplasmosis is frequent in HIV patients and presents diagnostic and therapeutic challenges that may be difficult to resolve in resource-poor settings. It is important that affordable generic drugs for treating histoplasmosis be made widely available in resource-poor countries.