PROTEIN-LOSING ENTEROPATHIES: HYPOALBUMINEMIA IS NOT ALWAYS A BAD SIGN

摘要

When concerned with protein loss of any cause, one should measure serum albumin concentrations (not serum total protein concentrations). Do not use human clinical pathology laboratories, as their technology typically does not detect canine albumin (meaning that they routinely report serum albumin concentrations of less than 1.5 gm/dl in clinically normal dogs). If the patient has substantial hypoalbuminemia, the first step is to examine the skin for obvious lesions that can cause protein loss. Cutaneous lesions sufficient to cause such hypoalbuminemia are obvious—you should be able to just look at the patient and know. Next, hepatic function testing (for example, resting and postprandial serum bile acid concentrations) and a urinalysis are requested. If there is any doubt on the urinalysis, then a urine protein/creatinine ratio will quantify the magnitude of urinary protein loss. Severe hypoalbuminemia (that is, less than 2 gm/dl) in an animal with diarrhea suggests a protein-losing enteropathy (PLE). If severe, exudative cutaneous disease, protein-losing nephropathy, and hepatic insufficiency are eliminated, then PLE is a reasonable tentative diagnosis in patients with a serum albumin less than 2.0 gm/dl. Contrary to what the textbooks say, PLEmay be associated with a low, normal, or increased serum globulin concentration.