A trial of Mel W in the treatment of Trypanosoma rhodesiense sleeping sickness

Abstract

Summary 1) During the first Mel W treatment of 17 patients with T. rhodesiense meningo-encephalitis, one patient who was already moribund, died. Six patients developed central nervous system reactions, classified as reactive encephalopathy. A reaction resembling diabetes insipidus may also have had a similar pathogenesis. Other effects included skin reactions (three patients), herpes occipito-collaris (one patient) and jaundice with melaena (one patient). Pyrexial reactions occurred, after the first dose of Mel W, in 11 of 14 patients treated without initial suramin. Pathological obesity, probably hypothalamic in origin, developed as a sequel of treatment in two patients. The pathogenesis of these unwanted effects of treatment has been discussed and the CSF protein changes have been described in a patient who became stuporous after the initial 4-day course of Mel W. 2) Mel W failed to cure at least nine of the 16 patients surviving treatment. In three patients, trypanosomes were isolated from the CSF by inoculation of albino rats immediately after a full course of Mel W. In one of these, the infection may have become latent or it may have died out; the other two showed frank deterioration and were re-treated with melarsoprol. Seven other relapses were diagnosed by CSF deterioration and by the detection of trypanosomes, by microscopy, in the CSF. 3) Re-treatment was delayed until at least one trypanosome was seen on microscopical examination of the CSF or the centrifuged deposit of the CSF. Nine patients were retreated with melarsoprol. Of these, four have died, two remain in poor condition and have not been cured, and three have remained in good health 14 months after treatment. 4) The results of this trial indicate that Mel W should not replace melarsoprol, which remains the drug of choice in T. rhodesiense meningo-encephalitis.