Impaired Anti-Schistosoma Seroreactivity in Advanced HIV Infection: Findings from a Cross-Sectional Study in Ghana

This study assessed the diagnostic reliability of anti-Schistosoma serology in Ghanaian patients with and without concomitant human immunodeficiency virus (HIV) infection. Serological testing was performed on serum samples containing PCR-confirmed Schistosoma spp. DNA using a commercial enzyme-linked immunosorbent assay (ELISA; EUROIMMUN, Lübeck, Germany). Following real-time PCR confirmation of either Schistosoma mansoni or Schistosoma haematobium complex DNA, samples were subjected to anti-Schistosoma IgG and IgM serology in duplicate. Results were qualitatively interpreted as positive, uncertain, or negative; reproducible positive results across test runs were defined as “consistent,” while all other profiles were classified as “inconsistent”. Serological consistency was then correlated with patient demographic and clinical data, including age, gender, HIV status, CD4+ and CD8+ T-lymphocyte counts, CD4+/CD8+ ratios, and HIV viral loads. Of the 41 individuals with PCR-proven schistosomiasis (S. mansoni, n = 36; S. haematobium, n = 5) and no clinical signs of Katayama syndrome, 39 were HIV-positive. Among these 39 coinfected patients, consistently positive serology was recorded in 27 (69.2%) cases for IgG and 31 (79.5%) cases for IgM. Consistent IgG seropositivity was significantly associated with higher CD4+ (293 vs. 58 cells/µL, p = 0.009) and CD8+ (981.5 vs. 306 cells/µL, p = 0.007) T-lymphocyte counts. The association between higher CD4+ cell counts and consistent IgG reactivity remained robust in multivariable analysis (adjusted odds ratio = 2.04 per 100 cells/µL, p = 0.01). A non-significant trend in the same direction was observed for anti-Schistosoma IgM, whereas no other significant associations with epidemiological or medical factors were identified. In conclusion, the state of cellular immunity critically influences the reliability of serological schistosomiasis diagnostics in HIV-positive individuals. For patients with severe cellular immune depletion and suspected schistosomiasis, alternative diagnostic approaches, such as highly sensitive real-time PCR, should be strongly considered.