Chronic Diarrhea: Diagnosis and Management

Abstract

Chronic diarrhea is a common problem affecting up to 5% of the population at a given time. Patients vary in their definition of diarrhea, citing loose stool consistency, increased frequency, urgency of bowel movements, or incontinence as key symptoms. Physicians have used increased frequency of defecation or increased stool weight as major criteria and distinguish acute diarrhea, often due to self-limited, acute infections, from chronic diarrhea, which has a broader differential diagnosis, by duration of symptoms; 4 weeks is a frequently used cutoff. Symptom clusters and settings can be used to assess the likelihood of particular causes of diarrhea. Irritable bowel syndrome can be distinguished from some other causes of chronic diarrhea by the presence of pain that peaks before defecation, is relieved by defecation, and is associated with changes in stool form or frequency (Rome criteria). Patients with chronic diarrhea usually need some evaluation, but history and physical examination may be sufficient to direct therapy in some. For example, diet, medications, and surgery or radiation therapy can be important causes of chronic diarrhea that can be suspected on the basis of history alone. Testing is indicated when alarm features are present, when there is no obvious cause evident, or the differential diagnosis needs further delineation. Testing of blood and stool, endoscopy, imaging studies, histology, and physiological testing all have roles to play but are not all needed in every patient. Categorizing patients after limited testing may allow more directed testing and more rapid diagnosis. Empiric antidiarrheal therapy can be used to mitigate symptoms in most patients for whom a specific treatment is not available.

Diabetes Mellitus and the Colon

“…Secondary causes of diarrhea should be sought out, especially conditions that are associated with diabetes such as small intestinal bacterial overgrowth (SIBO), hyperthyroidism, celiac disease, microscopic colitis, bile acid malabsorption, pancreatic insufficiency, infections (i.e., C. difficile colitis), medications, and diet (i.e., sorbitol, mannitol, xylitol, and lactose) [33, 34]. Diabetic medications represent a particularly common cause of diarrhea including metformin, acarbose, and miglitol [35].…”

Micronutrients in Liver Disease: Roles, Risk Factors for Deficiency, and Recommendations for Supplementation

“…Since the synthetic disaccharide is unabsorbable in the small intestine, it has an osmotic effect that can cause loose stools. Increased losses of micronutrients and electrolytes such as zinc, potassium, and magnesium are often seen with chronic loose stools as a result of malabsorption …”

Imaging Inflammation and Infection in the Gastrointestinal Tract

“…Identification of the etiology of abdominal pain is based primarily on structural differences with little knowledge about the molecular characteristics of the affected tissues, resulting in high rates of misdiagnosis and improper treatment. Along with similar physical presentations, many GI diseases also have similar bio-clinical symptoms such as, leukocytosis and fevers which are extremely nonspecific, providing little to no insight for a proper diagnosis [5]. At present, the ability to locally identify inflammation and infection within the GI tract is confined to anatomic methods.…”