Question: A patient says she has had chronic bowel problems for the last 10 years, with diarrhea or loose stool for two to three days in a row, then constipation for another week. Diagnostic tests are being ordered. Because the diagnostic tests are only covered for certain conditions, what diagnosis should be used? Colorado Subscriber Answer: Your ICD-9 report should include: 787.91 (Diarrhea), which describes the patient's abnormal frequency and fluidity of feces. This ICD-9 does not specify chronicity but best describes her symptoms with a code that should justify testing to rule out conditions which can cause similar bowel patterns and that can be treated.