Characteristics and risk factors for failure of horses with acute diarrheato survive: 122 cases (1990-1996)

Objective-To characterize horses with acute diarrhea and determine risk fac tors for failure to survive. Design-Retrospective study. Animals-122 adult horses admitted for acute diarrhea at the teaching hospit al between Jan 1, 1990 and Dec 31, 1996. Procedure-Medical records of horses with acute diarrhea were reviewed to ab stract information regarding signalment, history, physical examination, cli nicopathologic testing, treatment, and outcome. Results-91 of 122 (74.6%) horses lived and were discharged from the hospita l. Horses with history of administration of antimicrobials for a problem pr eceding diarrhea were approximately 4.5 times less likely to survive. The f ollowing variables that had been determined at the time of admission were s ignificantly associated with failure to survive: administration of antimicr obial drugs for another illness, serum creatinine concentration > 2.0 mg/dl , PCV > 45%, tachycardia (heart rate > 60 beats/min), and low serum total p rotein concentration. Prevalence of laminitis was 11.5%. Clinical Implications-Diarrheic horses that are azotemic and have clinicopa thologic findings consistent with hemoconcentration and hypoproteinemia hav e a poor prognosis for survival. Antimicrobial administration may induce di arrhea, and antimicrobial-associated diarrhea may have a worse prognosis th an other types of acute diarrhea.