Histoplasmosis in patients living with HIV in Europe: review of literature

Efficacy of nitrofuran derivatives against biofilms of Histoplasma capsulatum strains and their in vivo toxicity

AIM

To evaluate the efficacy of two nitrofuran derivatives against biofilms formed by two strains of Histoplasma capsulatum and to study the toxicity of these compounds in alternative models: Caenorhabditis elegans, Galleria mellonella, and zebrafish.

METHODS

The metabolic activity of biofilms was measured after treatment using the XTT reduction assay. Scanning electron microscopy (SEM) and confocal microscopy were used to observe damage to mature biofilms. Survival curves were generated for G. mellonella, while percentage survival was determined for C. elegans and zebrafish.

RESULTS

The compounds showed efficacy against early and mature biofilms at concentrations equal to or up to two times higher than those required to eliminate planktonic fungal cells (3.90 to 31.25 μg/mL). Micrographs showed a reduction in metabolic activity, biofilm thickness, and extracellular matrix. In addition, the compounds showed little or no toxicity in alternative models, even at the highest concentrations tested.

CONCLUSION

These results are promising for the development of new therapeutic alternatives, especially for species, such as H. capsulatum, which are recognized as high-priority pathogens. Few studies have investigated resistance and antifungal treatment targeting biofilms of this species, making this work a relevant contribution to future approaches.

Imported Systemic Endemic Mycoses in Spain 1997-2021: An Analysis of a National Hospital Database

BACKGROUND

Systemic endemic mycoses are systemic fungal infections typically found in tropical and subtropical regions. Their global incidence is rising, including in nonendemic countries, mainly due to migration and international travel. They are a major cause of morbidity and mortality worldwide, especially in immunocompromised patients. This study aimed to analyse incidence trends of endemic mycoses and their presentation in hospitalised patients in Spain from 1997 to 2021.

METHODS

This retrospective, observational study drew data from the Spanish National Hospital Discharge Database. We used the diagnostic codes of the 9th and 10th International Classification of Diseases for histoplasmosis, coccidioidomycosis, paracoccidioidomycosis and talaromycosis, retrieving systemic endemic mycoses cases from the national public registry.

RESULTS

Over the study period, 646 cases of histoplasmosis, 138 of coccidioidomycosis, 47 of paracoccidioidomycosis and 24 talaromycosis were reported, with a rising number of cases annually, driven mainly by an increase in histoplasmosis. A segmented linear regression predictive model with a 10-year forecast showed a steady increase, reaching 128 hospitalisations (95% confidence interval [CI] 87-168) in Spain in 2031. Overall, in-hospital mortality was 10.9%, higher in histoplasmosis (11.3%) and coccidioidomycosis (10.9%) and independently associated with immunosuppression for both histoplasmosis (adjusted odds ratio [aOR] 3.28, 95% CI 1.72-6.24; p < 0.001) and coccidioidomycosis (aOR 4.05, 95% CI 1.22-13.44; p = 0.022).

CONCLUSIONS

Hospitalisations for systemic endemic mycoses, especially histoplasmosis, are on the rise in Spain. Mortality is significant and primarily associated with immunosuppression. This trend is expected to continue in the coming years, underscoring the importance of maintaining hospital-based surveillance of endemic mycoses in nonendemic regions.

Disseminated Histoplasmosis Diagnosed in an Immunocompetent Patient from a Non-Endemic Area: Neglected or Emerging Disease?

Histoplasma capsulatum (H. capsulatum) is considered to be one of the most extensively spread dysmorphic fungi worldwide. Histoplasmosis primarily impacts patients with weakened immune systems and can result in a diverse range of clinical manifestations. In immunocompetent patients, the disease may manifest as a self-limiting or asymptomatic infection; however, in immunocompromised individuals, it can occur as a debilitating, disseminated disease. Diagnosing histoplasmosis may be challenging. A medical professional that specializes in treating endemic fungal illnesses is better able to assist with an accurate and timely diagnosis since they have a deeper grasp of these illnesses. Consequently, the process of diagnosing histoplasmosis might be difficult for less experienced physicians. The case presented is an example of the myriad faces that histoplasmosis can take on, mimicking other common infectious or malignant conditions, leading to extensive work-up and invasive procedures in establishing the diagnosis of this otherwise benign condition. We hereby report the case of disseminated histoplasmosis in a young immunocompetent female patient.