Diagnosing disseminated histoplasmosis in advanced HIV/AIDS disease in Cameroon using a point of care lateral flow assay

Abstract

Histoplasmosis is an AIDS-defining opportunistic infection. Disseminated histoplasmosis (DH) can be fatal without early diagnosis and treatment initiation. We present one confirmed and three probable cases of DH in advanced HIV/AIDS disease patients diagnosed using OIDx Histoplasma LFA in Yaoundé, Cameroon. Four women with HIV but unknown CD4 count presented with asthenia, weight loss, productive cough, and fever (39°C) as common symptoms for at least 3 weeks. Two of the patients had skin lesions. These included facial papules, macules, and umbilicated vesicles scattered over the trunk and limbs. These were diffuse lesions which were purulent, itching, and papillomatous lesions with a necrotic centre, and one patient had a right forearm ulcer. We performed the Histoplasma antigen tests using the OIDx Histo LFA, and they were strongly positive in all four patients. Histopathology in skin biopsy allowed identification of the species as Histoplasma capsulatum var capsulatum in one patient. In this same patient, Pseudomonas aeruginosa and Proteus mirabilis were cultured from the forearm ulcer. This patient later commenced antibiotics (Levofloxacin 500 mg) and oral itraconazole (800 mg/day) with immediate improvement. Unfortunately, the other three patients could not access itraconazole, were discharged and lost to follow-up. Early diagnosis and treatment are essential for the management of DH. LFA is a test that can be set up in any setting with limited resource. Access to this can be a major advance in the diagnosis of histoplasmosis in resource-limited settings.

The Current and Future States of Diagnostic Tests for Histoplasmosis with a Focus on People with HIV and Disseminated Histoplasmosis

“…The OIDx LFA was also positive in two of 75 controls [ 63 ]. One other report described positive results in four PWH suspected to have histoplasmosis in Cameroon [ 64 ]. In another study using urine samples from 78 PWH, including 25 with disseminated histoplasmosis and 53 controls (including 10 from people without HIV), sensitivity was 92% (23/25), but specificity was only 32% (17/53) [ 53 ].…”

“… Lateral flow assays from OIDx ( A ) and MiraVista ( B ). The left figure ( A ) shows the kit for the OIDx lateral flow assay [ 64 ]. On the right is a positive test using the MiraVista lateral flow assay ( B ) [ 65 ].…”

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

“…Although disease course in immunocompetent hosts is typically asymptomatic and self-limiting [ 7 ], acute histoplasmosis in individuals without co-morbidities has been reported [ [8] , [9] , [10] ]. A range of clinical presentations are described, including respiratory disease [ 11 , 12 ], which can mimic the clinical presentation and radiographic pattern of pulmonary Tuberculosis (TB) [ 13 , 14 ]; and cutaneous and bone lesions [ [15] , [16] , [17] ], described by the majority of case reports in West Africa [ 3 ].…”