Colic in horses can range from a benign bellyache to a life-threatening condition requiring emergency surgery. And while in most cases veterinarians identify severe colic cases relatively easily, they might have a more difficult time deciding if such cases require surgery or if they can be managed medically.

There might be hope, however, for veterinarians that must make this decision for certain colic case types—those with infectious causes. Danish researchers recently evaluated whether practitioners could use certain blood protein levels to distinguish surgical from nonsurgical colic cases. They presented their results at the 2013 American Association of Equine Practitioners’ Convention, held Dec. 7-11 in Nashville, Tenn.

The team looked at levels of three proteins–serum amyloid A, haptoglobin, and fibrinogen–as diagnostic markers for these infectious nonsurgical vs. surgical colics. These proteins are, noted Tina Holberg Pihl, DVM, PhD, assistant professor of medicine and surgery at the University of Copenhagen's Department of Large Animal Sciences, the most important “acute phase proteins” in the horse, levels of which rise when the horse fights inflammation .

The researchers studied these levels separately as well as in conjunction with analyzing common blood and peritoneal fluid (that which surrounds and lubricates the abdominal organs) factors such as white cell count, packed cell volume, total protein, and lactate to see if including these proteins could improve diagnostic accuracy. In doing so they examined records from 148 cases of severe colic.

Pihl said the researchers found serum amyloid A (SAA