Histoplasmosis is an important cause of mortality in patients with AIDS, especially in countries with limited access to antiretroviral therapies and diagnostic tests. However, many disseminated infections in Latin America go undiagnosed. A simple, rapid method to detect Histoplasma capsulatum infection in endemic regions would dramatically decrease time to diagnosis and treatment, reducing morbidity and mortality. The aim of this study was to validate a commercial monoclonal Histoplasma galactomannan (HGM) ELISA (Immuno-Mycologics [IMMY], Norman, Oklahoma, USA) in two cohorts of people living with HIV/AIDS (PLHIV). We analyzed urine samples from 589 people (466 from Guatemala and 123 from Colombia), including 546 from PLHIV and 43 from non-PLHIV controls. Sixty-three of these people (35 from Guatemala and 28 from Colombia) had confirmed histoplasmosis by isolation of H. capsulatum. Using the standard curve provided by the quantitative commercial test, sensitivity was 98% (95% CI, 95-100) and specificity was 97% (95% CI, 96-99) (cutoff=0.5 ng/mL). Semi-quantitative results, using a calibrator of 12.5 ng/mL of Histoplasma galactomannan to calculate an EIA Index Value (EIV) of the samples, showed a sensitivity of 95% (95% CI, 89-100%) and specificity of 98% (95% CI, 96-99%) (cutoff ≥2.6 EIV). This relatively simple-to-perform commercial antigenuria test showed a high performance, with reproducible results in both countries, suggesting that it can used to detect progressive disseminated histoplasmosis in PLHIV in a wide range of clinical laboratories in countries where histoplasmosis is endemic.

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.

Opportunistic infections (OIs) and advanced HIV disease (AHD) contribute to HIV-related mortality. Here, we analyzed the situation of AHD and OIs in a cohort of newly diagnosed HIV patients from Guatemala. We included 2127 adult patients from 13 facilities across the country during 2017 to 2018. Patients were screened for tuberculosis (TB), nontuberculous mycobacteria (NTM), histoplasmosis, and cryptococcal disease, independently of their CD4 cell count. Of the 2127 enrolled patients, 1682 (79.1%) had a CD4 cell count available; of which 52% presented with AHD. Of the Mayan population, 65% had AHD. The overall OI incidence was 21%. Histoplasmosis was the most frequent OI (7.9%), followed by TB (7.1%); 94.4% of these infections occurred in patients with a CD4 < 350 cells/mm³. Mortality at 180 days was significantly higher in those with OIs than without OIs (29.7% vs. 5.9%, p < 0.0001). In one year, this program decreased the OI mortality by 7% and increased the OI treatment by 5.1%. Early OI diagnosis and appropriate therapy reduced OI mortality among newly diagnosed HIV patients in Guatemala. Screening for OIs should be considered in all newly diagnosed HIV patients who have a CD4 cell count < 350 cells/mm³ or those without a CD4 cell count available. To improve results, interventions such as early HIV detection and access to flucytosine and liposomal amphotericin B are required.

A Diagnostic Laboratory Hub (DLH) was set up in Guatemala to provide opportunistic infection (OI) diagnosis for people with HIV (PWH). Patients newly presenting for HIV, PWH not receiving antiretrovirals (ARVs) for >90 days but returned to care (Return/Restart), and PWH on ARVs with symptoms of OIs (ARV treatment) were prospectively included. Screening for tuberculosis, nontuberculous mycobacteria (NTM), histoplasmosis, and cryptococcosis was done. Samples were couriered to the DLH, and results were transmitted electronically. Demographic, diagnostic results, disease burden, treatment, and follow-up to 180 days were analyzed. In 2017, 1953 patients were included, 923 new HIV infections (an estimated 44% of all new HIV infections in Guatemala), 701 on ARV treatment, and 315 Return/Restart. Three hundred seventeen (16.2%) had an OI: 35.9% tuberculosis, 31.2% histoplasmosis, 18.6% cryptococcosis, 4.4% NTM, and 9.8% coinfections. Histoplasmosis was the most frequent AIDS-defining illness; 51.2% of new patients had <200 CD4 cells/mm³ with a 29.4% OI incidence; 14.3% of OIs in new HIV infections occurred with CD4 counts of 200–350 cells/mm³. OIs were the main risk factor for premature death for new HIV infections. At 180 days, patients with OIs and advanced HIV had 73-fold greater risk of death than those without advanced disease who were OI-free. The DLH OI screening approach provides adequate diagnostic services and obtains relevant data. We propose a CD4 screening threshold of <350 cells/mm³. Mortality remains high, and improved interventions are required, including expansion of the DLH and access to antifungal drugs, especially liposomal amphotericin B and flucytosine.

Antifungal resistance is one of the major causes of the increasing mortality rates for fungal infections, especially for those caused by Aspergillus spp. A surveillance program was established in 2014 in the Spanish National Center for Microbiology for tracking resistance in the most prevalent Aspergillus species. A total of 273 samples were included in the study and were initially classified as susceptible or resistant according to EUCAST breakpoints.

Among people with HIV, histoplasmosis represents an important cause of mortality. Previous studies provided estimates of the disease incidence. Here, we compared those estimates with the results obtained from a screening program implemented in Guatemala, which included histoplasmosis detection for people with HIV. To compare the results of this program with previous estimations, a literature search was performed and reports concerning histoplasmosis incidence were analyzed. The screening program enrolled 6366 patients. The overall histoplasmosis incidence in the screening program was 7.4%, which was almost double that estimated in previous studies. From 2017 to 2019, the screening program showed an upward trend in histoplasmosis cases from 6.5% to 8.8%. Histoplasmosis overall mortality among those who were newly HIV diagnosed showed a decrease at 180 days from 32.8% in 2017 to 21.2% in 2019. The screening approach using rapid diagnostic assays detects histoplasmosis cases more quickly, allowing a specific treatment to be administered, which decreases the mortality of the disease. Therefore, the use of these new techniques, especially in endemic areas of histoplasmosis, must be implemented.