Bacteremia in equine neonatal diarrhea: a retrospective study (1990-2007).

BACKGROUND

Bacteremia in sick foals is associated with survival, but the association of bacteremia and diarrhea is not reported.

HYPOTHESIS

Neonatal foals with diarrhea will commonly be bacteremic.

ANIMALS

One hundred and thirty-three neonatal foals.

METHODS

Records of all foals <30 days of age presenting with diarrhea between January 1990 and September 2007 were reviewed.

RESULTS

Sixty-six of 133 foals (50%) were bacteremic at admission, with 75 isolates from the 66 samples. The blood culture from a further 18 foals (13.5%) grew coryneform bacteria. Nine foals (6.8%) had 2 or more organisms grown on blood culture. One foal had 5 different organisms, interpreted as contamination. Forty-eight foals (36%) had no growth on admission blood cultures. No cultures isolated fungal organisms. Excluding coryneform bacteria, 43 isolates (57%) were Gram-negative organisms and 32 isolates (43%) were Gram-positive organisms. The most common isolate was Enterococcus spp. (22 isolates, 29%), followed by Pantoea agglomerans (13 isolates, 17%). IgG concentration at admission was not associated with blood culture status. Blood culture status was not associated with survival to hospital discharge.

CONCLUSIONS AND CLINICAL IMPORTANCE

Bacteremia is common in neonatal foals with diarrhea. Decisions regarding antimicrobial selection should be made with these differences in mind.