HIV and Chagas Disease: An Evaluation of the Use of Real-Time Quantitative Polymerase Chain Reaction to Measure Levels of Trypanosoma cruzi Parasitemia in HIV Patients in Cochabamba, Bolivia

Abstract

This cross-sectional study evaluated epidemiologic characteristics of persons living with HIV (PWH) coinfected with Trypanosoma cruzi in Cochabamba, Bolivia, and estimated T. cruzi parasitemia by real-time quantitative polymerase chain reaction (qPCR) in patients with and without evidence of reactivation by direct microscopy. Thirty-two of the 116 HIV patients evaluated had positive serology for T. cruzi indicative of chronic Chagas disease (27.6%). Sixteen of the 32 (50%) patients with positive serology were positive by quantitative polymerase chain reaction (qPCR), and four of the 32 (12.5%) were positive by direct microscopy. The median parasite load by qPCR in those with CD4+ < 200 was 168 parasites/mL (73-9951) compared with 28.5 parasites/mL (15–1,528) in those with CD4+ ≥ 200 (P = 0.89). There was a significant inverse relationship between the degree of parasitemia estimated by qPCR from blood clot and CD4+ count on the logarithmic scale (rsBC= –0.70, P = 0.007). The correlation between T. cruzi estimated by qPCR+ blood clot and HIV viral load was statistically significant with rsBC = 0.61, P = 0.047. Given the significant mortality of PWH and Chagas reactivation and that 57% of our patients with CD4+ counts < 200 cells/mm3 showed evidence of reactivation, we propose that screening for chronic Chagas disease be considered in PWH in regions endemic for Chagas disease and in the immigrant populations in nonendemic regions. Additionally, our study showed that PWH with advancing immunosuppression have higher levels of estimated parasitemia measured by qPCR and suggests a role for active surveillance for Chagas reactivation with consideration of treatment with antitrypanosomal therapy until immune reconstitution can be achieved.

Chagas Disease in People with HIV: A Narrative Review

“…cruzi infection in people with HIV (PWH) generally reflects the prevalence in the at-risk HIV-negative population in the same location [ 14 ]. Reported rates of T. cruzi –HIV co-infection range from 1.3–5% in Brazil [ 5 ] to 1.2–4.2% in Argentina (7.1% in intravenous drug users) [ 4 , 15 ], and to 28% in a single Bolivian study [ 2 , 4 , 6 , 15 ]. In Latin American PWH living in non-endemic countries, T. cruzi co-infection rates range from 0% in one US screening study [ 16 ] to 1.9–10.5% in Spain [ 17 , 18 , 19 ].…”

“…In the setting of HIV– T. cruzi coinfection, the most widely used criteria require clinical manifestations that are not typical of chronic Chagas disease plus the demonstration of the parasite by microscopy in blood, cerebrospinal fluid [CSF], or other fluids or tissue [ 14 , 37 ]. However, some authors also include microscopically detectable parasitemia without a reactivation-defining syndrome [ 6 , 20 ]. Even in the absence of positive microscopy, parasitemia levels, as defined by molecular methods, are significantly higher in asymptomatic immunosuppressed patients compared to in immunocompetent patients with chronic T. cruzi infection [ 38 ].…”

“…Even asymptomatic PWH with chronic Chagas disease have significantly higher levels of T. cruzi parasitemia than HIV-negative people with chronic T. cruzi infection [ 26 , 32 ]. The level of parasitemia in PWH with chronic Chagas disease generally shows an inverse correlation with CD4 counts [ 6 , 32 ]. PCR sensitivity in chronic T. cruzi infection is variable but is generally higher in the coinfection setting because of the higher parasite load distribution [ 6 , 58 , 59 ].…”

“…More than six million people are estimated to be infected in the Americas [ 1 ]. In endemic countries such as Argentina, Brazil and Bolivia, 1–32% of people with HIV (PWH) are coinfected with T. cruzi [ 2 , 3 , 4 , 5 , 6 ]. While co-infected PWH can develop the classic cardiac and gastrointestinal manifestations of chronic Chagas disease seen in 20–30% of their HIV-negative counterparts, they have a higher risk of morbidity and mortality because their compromised cellular immunity may permit T. cruzi reactivation.…”

Chagas Disease in HIV-Infected Patients: It’s Time to Consider the Diagnosis

“…Reimer-McAtee et al. 12 conducted a cross-sectional study of T. cruzi prevalence among a Bolivian cohort of ambulatory and hospitalized HIV-infected individuals, identifying 28% T. cruzi seropositivity, and reactivation disease in 12.5% of T. cruzi seropositive individuals. They present compelling evidence that, regardless of specific signs or symptoms, HIV-infected patients from endemic countries should be tested for Chagas disease.…”