Histoplasmosis and Tuberculosis Co-Occurrence in People with Advanced HIV

Abstract

Distinguishing between histoplasmosis, tuberculosis (TB), and co-occurrence of disease is a frequent dilemma for clinical staff treating people with advanced Human Immunodeficiency Virus (HIV) infection. This problem is most frequently observed in clinical settings in countries where both diseases are endemic. It is also a challenge outside these endemic countries in HIV clinics that take care of patients coming from countries with endemic histoplasmosis and TB. The gold standard for diagnosis of both of these diseases is based on conventional laboratory tests (culture, histopathology and special stains). These tests have several limitations, such as lack of laboratory infrastructure for handling isolates (biosafety level 3), shortage of laboratory staff who have appropriate training and experience, variable analytical performance of tests and long turn-around time. Recently, novel rapid assays for the diagnosis of histoplasmosis and TB became available. However, this technology is not yet widely used. Mortality in immunocompromised patients, such as people with advanced HIV, is directly linked with the ability to rapidly diagnose opportunistic diseases. The aim of this review is to synthesize the main aspects of epidemiology, clinical characteristics, diagnosis and treatment of histoplasmosis/TB co-occurrence in people with advanced HIV.

Screening for invasive fungal disease using non‐culture‐based assays among inpatients with advanced HIV disease at a large academic hospital in South Africa

“…Co‐infection with multiple opportunistic pathogens is well documented among patients with advanced HIV disease 29 . In Colombia, 51% of people living with HIV with progressive disseminated histoplasmosis had at least one other OI at the time of presentation.…”

HIV patients dying on anti-tuberculosis treatment: are undiagnosed infections still a problem in French Guiana?

“…[1] Histoplasmosis is hard to diagnose because it requires mycological expertise and because the fungal growth is slow. Moreover, histoplasmosis is frequently associated with tuberculosis (ranging from 2 to 38% and in most countries over 10%) [2]. This diagnostic difficulty is estimated to cause large numbers of deaths often attributed to tuberculosis [3][4][5].…”

Evaluation of a Histoplasma antigen lateral flow assay for the rapid diagnosis of progressive disseminated histoplasmosis in Colombian patients with AIDS

“…Early diagnosis is critical for providing proper treatment; however, diagnosis of PDH can be challenging. Symptoms in PLHIV may lack specificity and be similar to opportunistic infections, especially infections caused by Mycobacterium species, complicating diagnosis and treatment of PDH, especially in geographic regions where tuberculosis and other opportunistic infections are frequent …”

“…Symptoms in PLHIV may lack specificity and be similar to opportunistic infections, especially infections caused by Mycobacterium species, complicating diagnosis and treatment of PDH, especially in geographic regions where tuberculosis and other opportunistic infections are frequent. [2][3][4][5] Laboratory diagnosis by culture can take weeks and serology may be falsely negative early in infection or as a result of immunosuppression in these patients. 6,7 Recently, an in-house Western blot assay has reported high sensitivity to diagnose PDH in HIV (90% sensitivity), but this assay is not commercially available.…”