Screening of antibacterial drugs for antimicrobial activity against Pythium insidiosum.

We tested 25 isolates of Pythium insidiosum to investigate their susceptibility to antibacterial drugs that act through inhibition of protein synthesis or other mechanisms of action. We observed that tetracycline, erythromycin, linezolid, nitrofurantoin, Synercid (quinupristin and dalfopristin), chloramphenicol, clindamycin, cetrimide, and crystal violet had inhibitory activity against P. insidiosum. Those in vitro results suggest that antibacterials that inhibit protein synthesis should be the primary antimicrobials investigated for the treatment of pythiosis in animals and humans.