From the Guidelines
Chronic diarrhea is defined as loose, watery stools that persist for four weeks or longer, characterized by increased stool frequency, volume, or altered consistency, and is a condition that differs from acute diarrhea, which typically resolves within a few days. This definition is based on the most recent and highest quality study, which emphasizes the importance of duration of symptoms in distinguishing chronic from acute diarrhea 1. The study highlights that symptoms persisting for longer than 4 weeks suggest a non-infectious aetiology and merit further investigation.
Key Characteristics of Chronic Diarrhea
- Increased stool frequency, typically more than three bowel movements per day
- Increased stool volume
- Altered stool consistency, which can be assessed using the Bristol stool chart, with types 5 and above indicating diarrhea
- The condition may be continuous or intermittent, with periods of normal bowel function between episodes
Causes and Diagnosis of Chronic Diarrhea
Causes of chronic diarrhea are diverse and include:
- Inflammatory bowel disease
- Irritable bowel syndrome
- Microscopic colitis
- Celiac disease
- Pancreatic insufficiency
- Bile acid malabsorption
- Medication side effects
- Infections
- Malabsorption syndromes Diagnosis typically requires medical evaluation, including stool tests, blood work, and possibly endoscopic procedures, as outlined in the guidelines for the investigation of chronic diarrhea in adults 1.
Importance of Medical Attention
Chronic diarrhea can lead to complications such as dehydration, electrolyte imbalances, and malnutrition if left untreated, making medical attention important for persistent symptoms. The guidelines emphasize the need for clear guidance on investigations and the importance of excluding cancer or inflammation, and detecting common disorders such as bile acid diarrhea, microscopic colitis, and lactose malabsorption 1.
From the Research
Definition of Chronic Diarrhea
- Chronic diarrhea is defined as symptoms lasting longer than 4 weeks 2, 3, 4.
- It is characterized by loose stool consistency, increased frequency, urgency of bowel movements, or incontinence 4.
- The definition of diarrhea varies among patients, but physicians often use increased frequency of defecation or increased stool weight as major criteria 4.
Prevalence of Chronic Diarrhea
- Chronic diarrhea affects up to 5% of the adult population 2, 5, 3, 4.
- It is a common clinical problem that can be difficult to evaluate and manage due to its extensive differential diagnosis 5.
Causes of Chronic Diarrhea
- Chronic diarrhea can be caused by various factors, including drug side effects, postoperative anatomic and physiologic alterations, intestinal and colonic wall abnormalities, inflammatory or malabsorption causes, pancreatobiliary diseases, and functional or gut-brain axis disorders associated with dysbiosis or gastrointestinal motility alterations 2.
- Infections are an uncommon cause of chronic diarrhea, but parasites like giardia, cryptosporidia, and cyclospora can be responsible 6.
- Other causes of chronic diarrhea include irritable bowel syndrome, inflammatory bowel disease, and small intestinal bacterial overgrowth 5, 4.