Neuro-inflammatory risk factors for treatment failure in “early second stage” sleeping sickness patients treated with Pentamidine

In a clinical trial on efficacy of Pentamidine in second stage Trypanosoma brucei gambiense patients with ≤20 cells/μl in cerebrospinal fluid (CSF), 43% of treatment failures were observed. We hypothesised that unsuccessful treatment was caused by uncured brain infection. The relationship between treatment outcome and CSF cell count, protein concentration, presence of trypanosomes, the intrathecal immune response, and CSF total IgM and trypanosome specific antibodies detected by LATEX/IgM and LATEX/ T.b. gambiense card agglutination tests was examined. Cell counts of 11–20 cells/μl, intrathecal IgM synthesis, CSF end-titres in LATEX/IgM ≥4 and LATEX/ T.b. gambiense positive CSF, were associated with treatment failure. Detection of intrathecal IgM synthesis is valuable for assessment of brain involvement and treatment decision.