Progressive disseminated histoplasmosis with concomitant disseminated nontuberculous mycobacterial infection in a patient with AIDS from a nonendemic region (California)

Epidemiological, clinical, diagnostic, and therapeutic features of histoplasmosis: A systematic review

Histoplasmosis is a mycosis due to a dimorphic fungus Histoplasma capsulatum. This study aimed at providing an overview of histoplasmosis epidemiological, clinical, diagnostic, and therapeutic aspects from the last 30 years. This review was carried out using a systematic literature search on histoplasmosis from 1992 to 2021. We describe the clinical features, diagnostic methods and treatment. Empirical searches were conducted via the databases PubMed, Google Scholar and Science Direct. Between 1992 and 2021, 190 manuscripts were published and reported 212 cases of histoplasmosis. These publications included 115 and 97 cases of American and African histoplasmosis respectively. The number of publications increased over the last ten years with a maximum in 2020 (12.34 % of the cases reported). The disseminated forms of histoplasmosis were the most frequently reported cases as compared to the localized forms. This was the case with the American histoplasmosis (75.65 %) as well as with the African histoplasmosis (55.67 %). Itraconazole (31.17 %) and Amphotericin B (26.62 %) were the most used drugs in the management of these cases. American histoplasmosis is distributed worldwide whereas African histoplasmosis is mainly present in intertropical Africa. There is a critical need for setting up a global surveillance system, towards a better understanding of the disease.

Disseminated Histoplasmosis in a Patient With Acquired Immunodeficiency Syndrome in a Non-Endemic Region (California)

Histoplasmosis is caused by infection with Histoplasma capsulatum (H. capsulatum). Progressive disseminated histoplasmosis is a more severe form of histoplasmosis and is seldom diagnosed in non-endemic regions of the world owing to the fungus's geographical distribution. In the United States (USA), Histoplasma capsulatum is classically known to be endemic to the Mississippi and Ohio River valleys, and cases in non-endemic areas, such as the southwest USA, are exceedingly rare. Patients with acquired immunodeficiency syndrome (AIDS) are at risk for infection with H. capsulatum, and failure to recognize and treat histoplasmosis may be devastating to patients. In non-endemic regions, the proposed mechanism for disseminated histoplasmosis in AIDS patients is reactivation of a previous infection. Here, we present the case of a young male patient who presented to a southern California hospital with diarrhea, was diagnosed with AIDS, and developed acute hypoxic respiratory failure. Chest imaging revealed diffuse reticulonodular opacities, and histoplasmosis was confirmed by urine and serologic examination. He was subsequently treated with liposomal amphotericin B and safely discharged from the hospital with oral itraconazole therapy. This case contributes to the current limited body of literature citing histoplasmosis infections in California, and clinicians should consider histoplasmosis as a differential diagnosis in non-endemic regions.

A Case of Disseminated Histoplasmosis From California, in the Setting of Secondary Hemophagocytic Lymphohistiocytosis: A Diagnostic Challenge

Histoplasma capsulatum is a geographically specific dimorphic fungus that can cause a spectrum of diseases. While most cases are asymptomatic pulmonary infections, in severe cases, particularly in immunocompromised patients, disseminated disease can occur. Histoplasmosis in California is limited to only a few case reports. In this article, we describe a rare case of disseminated histoplasmosis in a non-endemic region presenting with diagnostically challenging symptomatology, including altered mental status, status epilepticus, septic shock, and bilateral adrenal masses.

Opportunist Coinfections by Nontuberculous Mycobacteria and Fungi in Immunocompromised Patients

Nontuberculous mycobacteria (NTM) and many fungal species (spp.) are commonly associated with opportunistic infections (OPIs) in immunocompromised individuals. Moreover, occurrence of concomitant infection by NTM (mainly spp. of Mycobacterium avium complex and Mycobacterium abscessus complex) and fungal spp. (mainly, Aspergillus fumigatus, Histoplasma capsulatum and Cryptococcus neoformans) is very challenging and is associated with poor patient prognosis. The most frequent clinical symptoms for coinfection and infection by single agents (fungi or NTM) are similar. For this reason, the accurate identification of the aetiological agent(s) is crucial to select the best treatment approach. Despite the significance of this topic it has not been sufficiently addressed in the literature. This review aims at summarizing case reports and studies on NTM and fungi coinfection during the last 20 years. In addition, it briefly characterizes OPIs and coinfection, describes key features of opportunistic pathogens (e.g., NTM and fungi) and human host predisposing conditions to OPIs onset and outcome. The review could interest a wide spectrum of audiences, including medical doctors and scientists, to improve awareness of these infections, leading to early identification in clinical settings and increasing research in the field. Improved diagnosis and availability of therapeutic options might contribute to improve the prognosis of patients’ survival.

Histoplasma capsulatum and Mycobacterium avium co-infection in an immunocompromised patient: Case report and literature review

We report a case of fungal and mycobacterial co-infection in an immunosuppressed patient from Southern Brazil. Histoplasmosis was diagnosed in an AIDS patient admitted to the hospital with nonspecific respiratory signs. However, 4 months post hospital discharge, the patient worsened and a co-infection with Mycobacterium avium was detected. Physicians must consider and investigate a broad spectrum of diseases which can occur as co-infections and which share the same clinical symptoms and signs in immunosuppressed patients.

Drug resistance and pathogenic spectrum of patients coinfected with nontuberculous mycobacteria and human-immunodeficiency virus in Chengdu, China

BACKGROUND

Human-immunodeficiency virus (HIV) infection is increasing worldwide and nontuberculous mycobacteria (NTM) is an established microbiologic cause of pulmonary disease, lymphadenitis, and disseminated disease in cases of advanced immune suppression. Data on patients coinfected with HIV and NTM are limited. Thus, this study aimed to analyze the clinical characteristics, drug resistance, and pathogen spectrum of patients coinfected with both HIV and NTM in the Chengdu area of China.

METHODS

Data of 59 patients coinfected with both HIV and NTM collected from the Public Health Clinical Center of Chengdu, between January 2014 and December 2018, were analyzed. NTM drug sensitivity testing was performed using the microporous plate ratio method. Data were analyzed using SPSS 19.0, and the change in drug resistance rate was analyzed using the chi-square (χ) test.

RESULTS

Seven species/complex of NTM were identified from patients coinfected with HIV and NTM in this study, with Mycobacterium avium-intracellulare complex (52.5%) and M. kansasii (27.1%) as the predominant species. Male patients were more affected 50/59 (84.7%); the mean age of the 59 cases was 45 years. The clinical characteristics mainly included anemia (86.4%), cough and expectoration (79.7%). The baseline CD4 count was <50 cells/μL (84.7%). Patients were mainly in advanced acquired immunodeficiency syndrome (AIDS) stage. Chest imaging mainly showed patchy shadows (42.4%) and nodules (32.2%), with various degrees of AIDS-defining diseases. The drug resistance of NTM was severe, and the rate of isoniazid resistance (100.0%) was the highest, followed by rifampicin (94.9%), streptomycin (94.9%), ofloxacin (93.2%), and others. Ethambutol (52.5%) and clarithromycin (33.9%) were relatively low. No significant difference was found in the drug resistance rate of NTM strain against nine antituberculosis drugs in 5 years (P > 0.05).

CONCLUSIONS

The immune level of patients coinfected with HIV and NTM is low in advanced AIDS stage; more male are affected in patients who are mainly infected with MAC and M. kansasii and with serious drug resistance. The drug resistance rate of ethambutol and clarithromycin is relatively low.