Question

Etiopathogenesis of Chronic Diarrhoea.

Hint:

Chronic diarrhoea requires a thorough workup to differentiate between infectious, inflammatory, malabsorptive, and functional causes.

Answer 1

Chronic diarrhoea is defined as the passage of loose or watery stools for more than 4 weeks. It can result from a variety of underlying causes, including infections, inflammatory conditions, and metabolic disorders.
1. Infectious Causes:
- Parasitic Infections: *Giardia*, *Entamoeba histolytica*, and *Strongyloides* are common parasitic infections that lead to chronic diarrhoea.
- Bacterial Infections: Infections with *Salmonella*, *Campylobacter*, *Shigella*, and *Clostridium difficile* can lead to prolonged diarrhoea, especially in immunocompromised individuals.
- Viral Infections: Some viruses, like rotavirus, can cause prolonged diarrhoea, particularly in children.
2. Inflammatory Causes:
- Inflammatory Bowel Disease (IBD): Includes Crohn's disease and ulcerative colitis, which are chronic inflammatory conditions of the gastrointestinal tract that cause diarrhoea, along with abdominal pain and weight loss.
- Celiac Disease: An autoimmune disorder triggered by gluten that causes chronic diarrhoea, bloating, and malabsorption.
- Microscopic Colitis: A form of IBD that can cause chronic watery diarrhoea, often seen in older adults.
3. Malabsorptive Disorders:
- Lactose Intolerance: Inability to digest lactose leads to diarrhoea after the consumption of dairy products.
- Pancreatic Insufficiency: In conditions like chronic pancreatitis, the lack of pancreatic enzymes results in malabsorption and chronic diarrhoea.
4. Endocrine Causes:
- Hyperthyroidism: Increased thyroid hormone levels can cause increased gut motility, resulting in chronic diarrhoea.
- Diabetes Mellitus: Diabetic patients may suffer from autonomic neuropathy, which affects gut motility and leads to diarrhoea.
5. Medications and Toxins:
- Antibiotics: Broad-spectrum antibiotics can disrupt the normal gut flora, leading to antibiotic-associated diarrhoea or Clostridium difficile infections.
- Chemotherapy: Diarrhoea can be a side effect of chemotherapy.
6. Functional Disorders:
- Irritable Bowel Syndrome (IBS): This functional gastrointestinal disorder can cause chronic diarrhoea, often associated with abdominal cramping and bloating.