Thrombotic microangiopathy as a complication of medicinal leech therapy.

Medicinal leeches (hirudo medicinalis) are increasingly used as a useful therapeutic option in various medical and surgical settings. The potential complications associated with this therapy include infections with Aeromonas species, bleeding, anemia, and allergic reactions. We describe a patient who developed thrombotic microangiopathy and acute renal failure following leech therapy. It is proposed that the series of nonhuman proteins within leech saliva may be capable of injuring the endothelium.