Sleeping sickness and false positive HIV rapid tests: a substantial clearance of false positives occurs during therapy

Approaching the mechanisms related to HIV rapid diagnostic tests (RDT) false positives in patients with sleeping sickness may help to improve the accuracy of screening for HIV infection in areas endemic for Human African trypanosomiasis (HAT). We report on a patient from Congo who was managed like an AIDS-associated meningoencephalitis, based on a false positive HIV RDT at admission, and eventually received a diagnosis of sleeping sickness. A further retrospective cohort study performed in patients with sleeping sickness shows that most of positive HIV RDT obtained prior to treatment for sleeping sickness are false positives. We found that half of them were cleared at the end of treatment course, suggesting an early clearance of some antibodies involved in cross-reactivity. A substantial clearance of HIV RDT false positives occurs during therapy for HAT. In areas where Elisa HIV tests are not readily available, repeating the HIV RDT at the end of therapy may help to identify half of false positives.