Evaluation of complement mediated lysis in chronic chagasic patients treated with trypanosomicidal drugs

Abstract

Levels of lytic antibodies were determined by complement mediated lysis (CoML) in chronic chagasic patients treated with nifurtimox orbenznidazole. Two groups of patients were studied: one who had been treated more than six years ago and another with less than six years since treatment, although serologic reactions remained positive. CoML was carried out in two samples obtained from patients on different occasions, in test groups as well as in positive controls. In view of results observed sensitivity of reaction (83.3%) and its specifity (100.0%) were calculated. It was observed that about half of the patients presented lysis up to 20% and this result may corroborate "parasitological cure". It was noted that 43.6% of patients treated more than six years ago and 20.0% of patients with less than six years since treatment presented variable results, either positive or negative, differing for each sample from the same individual. Such results were thus considered as inconclusive, since parasitological tests remain negative. A prolonged follow-up may shed light over such results.