Serum arginase, a biomarker of treatment efficacy in human African trypanosomiasis.

Arginase serum levels were increased in human African trypanosomiasis patients and returned to control values after treatment. Arginase hydrolyzes l-arginine to l-ornithine, which is essential for parasite growth. Moreover, l-arginine depletion impairs immune functions. Arginase may be considered as a biomarker for treatment efficacy.