Decrease in Seminal HIV-1 RNA Load After Praziquantel Treatment of Urogenital Schistosomiasis Coinfection in HIV-Positive Men-An Observational Study

Abstract

Background: Urogenital schistosomiasis due to Schistosoma hematobium infection is hypothesized to cause increased HIV-1 RNA shedding in semen in HIV co-infected men as result of chronic egg-induced inflammation in the prostate and the seminal vesicles. The effect of treatment with the antihelminthic agent praziquantel on seminal HIV-1 RNA load was assessed in this study.

Methods: HIV-1 RNA load was determined in blood plasma and semen at baseline and at 10-week follow-up. Praziquantel was administered at baseline and two weeks later.

Results: Eighteen HIV-positive men with S. haematobium co-infection were enrolled into the study. Status of antiretroviral therapy (ART): 6 ART-naïve and 12 ART-experienced. All participants became egg-negative in urine at follow-up. Among the ART-naïve men, the mean HIV-1 RNA load decreased by 0.32 log₁₀ copies per mL (4.41 vs 4.09) in blood plasma from baseline to follow-up, and in semen by 1.06 log₁₀ copies per mL (4.06 vs 3.00).

Conclusions: This study demonstrated a decline in seminal HIV-1 RNA load following praziquantel treatment of urogenital schistosomiasis infection in HIV-positive men. The finding needs further exploration in a larger randomized study targeting praziquantel as a supplementary preventive measure of sexual transmission of HIV-1 in S. haematobium endemic areas in sub-Saharan Africa.

Keywords: HIV; HIV-1 RNA; Schistosoma haematobium; praziquantel; semen; urogenital schistosomiasis.

Figure 1.

Flow chart showing the population of males of reproductive age in the Ngundu area and how these males were approached by different inclusion strategies (A, B, and C, respectively), leading to identification of 22 eligible candidates co-infected with HIV and schistosomiasis, among whom 18 took part in the final study. Abbreviations: ART, antiretroviral therapy; SH, Schistosoma haematobium.

Figure 2.

Comparison of paired HIV-1 RNA loads in plasma and in semen, respectively, in antiretroviral therapy (ART)–naïve patients at baseline and at follow-up after praziquantel treatment. SPSS version 16 and R version 3.2.1 were used for data analysis [23]. S. haematobium infection intensity was expressed as number of eggs/10 mL urine. Mean blood plasma and semen HIV-1 RNA copies counted were log₁₀ transformed. Calculation of mean HIV-1 RNA load in plasma, or an HIV-1 RNA result of less <1.3 log₁₀ copies in semen, was determined to be 1.28 log₁₀ copies (19 copies)/mL, and a negative result to be 0 log₁₀ copies /mL. A paired t test was applied to test for changes in mean HIV-1 RNA load from baseline to follow-up. The confidence intervals in Figure 2 were obtained by use of a linear mixed model with random intercept.