EQUINE CANTHARIDIASIS

Equine cantharidiasis usually results from ingestion of alfalfa hay co ntaminated with blister beetles that contain the toxin cantharidin. Al though clinical signs of the condition vary greatly, gastrointestinal disturbances, pollakiuria, and evidence of hypocalcemia are frequently evident. Consistent laboratory findings include low urine specific gr avity despite hemoconcentration, hypocalcemia, hypomagesemia, mild azo temia, and elevations in serum creatine kinase values. Early supportiv e therapy is indicated and consists of decontamination and evacuation of the gastrointestinal tract, intravenous balanced electrolyte soluti ons. calcium supplementation, and gastrointestinal protectants. Urinar y cantharidin assay via gas chromatography-mass spectrometry or high-p ressure liquid chromatography can provide antemortem diagnostic confir mation of the condition. Significant necropsy lesions include enteroco litis, cystitis, and myocardial necrosis. Vesiculating gastropathy of the squamous mucosa (caused by the specific acantholytic effect of can tharidin) is a highly diagnostic finding.