Reply To: High Bile Acids
Hope you are well. Interesting case. Those bile acids are pretty impressive. I think repeating the sample if you have any doubt is never a bad idea. I am not sure how much more ammonia would add to this case, I am not sure I would bother running that. Aquired shunts definitely have to be a consideration but you could not completely rule out a congenital shunt! I have diagnosed them in 11-year-old dogs before!
Typical cutoff values for pre- and postprandial bile acids are 15 mcmol/L and 25 mcmol/L, respectively. Pre- and postprandial bile acids elevations have been reported to be 99% sensitive and 95-100% specific for the diagnosis of a PSS in dogs and cats. A study investigating the sensitivity and specificity of fasting bile acids in diagnosing PSS found them to be 93% and 67% in dogs, and 100% and 71% in cats, respectively. When increasing the cutoff value to 58 mcmol/L in dogs and 34 mcmol/L in cats the sensitivity was unchanged in dogs (91%) and was decreased in cats (83%), but the specificity increased in both species (84% in dogs, 86% in cats).
Falsely elevated postprandial values can occur with lipemia. When used as a test of hepatobiliary function, the magnitude of elevation in serum bile acids does not allow differentiation of the category of disease, with the exception that patients with vacuolar hepatopathy rarely have marked elevations (greater than 75-100 mcmol/L).
If increased next steps would definitely be abdominal imaging (ultrasound or CT).
Hope that helps.