Actinobacillus sp. bacteremia in foals: clinical signs and prognosis.
Medical records of 101 blood culture-confirmed bacteremic foals were reviewed to determine whether foals with Actinobacillus sp. bacteremia are affected at an earlier age, have more severe signs of disease, and have a worse prognosis than do foals with bacteremia of other causes. Thirty percent (30/101) of bacteremic foals had Actinobacillus sp. cultured, and these were 2 times more likely to die (crude odds ratio [OR(CR)] 0.8, 4; P = .14), with a survival rate of 43% (13/30) compared to the overall survival rate of 55% (56/101). When compared to other bacteremic foals, foals with actinobacillosis were 7 times more likely to have been sick from birth (adjusted odds ratio [OR(ADJ)] 2, 26; P = .003) and 6 times more likely to have diarrhea (OR(ADJ) 1, 22; P = .009). By bivariate analysis. foals with Actinobacillus sp. bacteremia were 5 times more likely to have a sepsis score >11 (OR(CR) 1, 18; P = .007), 6 times more likely to be obtunded (OR(CR) 2, 20; P = .005), and 3 times more likely to have pneumonia (OR(CR) 1, 7; P = .03). Furthermore, Actinobacillus sp. bacteremic foals were 27 times more likely to have a segmented neutrophil count <3.3 X 10(9) cells/L (OR(ADJ) 4, 166: P < .0001) and were 4.5 times more likely to have a band neutrophil count >0.46 x 10(9) cells/L (OR(ADJ) 1, 17; P = .02) when compared to foals that had bacteremia caused by either gram-negative enteric or gram-positive organisms. Sepsis score was < or = 11 in 49% (29/59) of bacteremia foals aged <13 days for which a discernible sepsis score was calculable. Results of this study should improve the diagnostic sensitivity of clinical examinations of neonatal foals, thereby facilitating treatment decisions.
Stewart
Allison J
AJ
Department of Veterinary Clinical Sciences, The Ohio State University, Columbus 43210, USA.
Hinchcliff
Kenneth W
KW
Saville
William J A
WJ
Jose-Cunilleras
Eduard
E
Hardy
Joanne
J
Kohn
Catherine W
CW
Reed
Stephen M
SM
Kowalski
Joseph J
JJ
D000187:Actinobacillosis / Q000453:epidemiology / Q000473:pathology; D000188:Actinobacillus / Q000302:isolation & purification*; D000818:Animals; D000831:Animals, Newborn; D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D001421:Bacteria, Anaerobic / Q000302:isolation & purification; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000302:isolation & purification; D006734:Horse Diseases / Q000382:microbiology / Q000401:mortality* / Q000473:pathology; D006736:Horses; D009820:Ohio / Q000453:epidemiology; D011379:Prognosis; D011996:Records / Q000662:veterinary; D012189:Retrospective Studies; D016019:Survival Analysis