[Plasmodium falciparum: interpretation of the semi-microtest of in vitro chemosensitivity by H3-hypoxanthine incorporation].

Recent advances in cultivation methods and knowledge of in vitro response of Plasmodium falciparum to antimalarials have led to improved chemosensitivity tests. The semimicrotest is a useful tool for screening presumptive antimalarials, and also for the testing sensitivity of strains recovered from patients in hospital and field studies to currently used drugs. Microscopic parasite counts on thin blood films can be replaced by measurement of 3H-hypoxanthine by the uptake parasite. Conditions which ensure optimal parasite growth and high radioisotope incorporation are described. Wells containing less than 3. 10(4) asexual parasites can be studied with this method. Results of the semi-microtest are closely correlated with those of microscopic parasite count. Advantages of both methods are discussed.