General workup
2.3.2.1 Case history
It is essential to obtain a thorough case history in all patients (see 1.1). This is best accomplished by asking a series of broadbased questions. The most important questions cover the present condition as to the duration of clinical signs and their characterization.
In addition, questions concerning the previous clinical history, including previous diagnoses and therapies, should always be asked. Finally, questions concerning travel and dietary history should be asked. Characterization of the stool may help to differentiate signs of small and large bowel diarrhea. Small bowel diarrhea is most often characterized by the presence of large quantities of soft-formed, bulky, or watery stools. Steatorrhea may also be evident. Chronic cases of small bowel diarrhea are also often accompanied by weight loss. In contrast, large bowel diarrhea most often is associated with a loose and stringy consistency due to increased mucus content. Streaks of fresh blood and tenesmus may also be present.2.3.2.2 Physical examination
The physical examination should begin by observing the unrestrained patient on the floor. The animal’s size, weight, mentation, posture, and behavior should be evaluated.
Abdominal palpation is an important part of the physical examination. Palpation must be systematic and the best sensitivity is afforded by alternating application and release of firm inward pressure on the abdomen by the fingers of both hands laid flat against the patient’s abdomen. Raising the front end of the animal facilitates palpation of cranial abdominal organs. The intestines should feel soft, smooth, and should slide freely between the examiner’s fingers.
A digital examination of the rectum is also important. The rectal examination also provides a stool sample, enabling evaluation of its consistency, color, and odor. Also, the fecal sample can be examined for any evidence of fresh blood, mucus, or melena.
2.3.2.3 Laboratory evaluation
Basic laboratory evaluation includes a CBC and a serum biochemistry profile comprising a minimum of blood urea nitrogen, creatinine, glucose, alanine aminotransferase (ALT), alkaline phosphatase (ALP), total protein, albumin, cholesterol, sodium, and potassium. In addition to general blood work aimed at identifying many secondary causes of chronic diarrhea, specific tests include the measurement of serum concentrations of trypsin-like immunoreactivity (TLI), pancreatic lipase immunoreactivity (PLI), folate, and cobalamin.
2.3.3