Diarrhoea

Diarrhea, characterized by frequent, loose, or watery stools, is a common condition with numerous potential causes. Its management is as crucial as understanding its causes, diagnosis, and differential diagnosis.

Causes

  • Infections:
    • Viral (e.g., Norovirus, Rotavirus, Adenovirus),
    • bacterial (e.g., Salmonella, E. coli, Campylobacter, Shigella, Yersinia), and
    • parasitic (e.g., Giardia) infections are primary causes.
    • Contaminated food or water, poor hygiene, and travel to endemic areas increase risk.
  • Chronic Diseases: Conditions like Crohn’s disease, ulcerative colitis, IBS, celiac disease, and malabsorption syndromes can lead to chronic diarrhea.
  • Medications and Therapies: Antibiotics can disrupt the normal gut flora. Laxatives, antacids containing magnesium, chemotherapy, and radiation can also cause diarrhea.
  • Diet and Lifestyle: Overconsumption of caffeine or alcohol, lactose intolerance, and artificial sweeteners (like sorbitol) can induce diarrhea.
  • Post-Surgical Causes: Procedures like gallbladder removal can affect bile acid absorption, leading to diarrhea.
  • Endocrine Causes: Conditions like hyperthyroidism or diabetes can cause diarrhea due to rapid gut transit.

Diagnosis

  • History and Examination
  • Laboratory Tests: Stool cultures, ova and parasite tests, and Clostridium difficile testing, especially after antibiotic use.
  • Blood Tests: Complete blood count for signs of infection; electrolyte and kidney function tests.
  • Endoscopic Procedures: Colonoscopy or sigmoidoscopy for direct visualization, particularly in chronic cases.
  • Imaging: Abdominal ultrasound, CT scan, or MRI for detailed views of the abdominal cavity.

Differential Diagnosis

  • Gastroenteritis: Often infectious, characterized by sudden onset following exposure to contaminated food or water.
  • Irritable Bowel Syndrome (IBS): Typically presents with abdominal pain relieved by defecation, bloating, and changes in stool consistency.
  • Inflammatory Bowel Diseases: Chronic inflammation of the GI tract with symptoms like bloody diarrhea, abdominal pain, weight loss.
  • Functional Disorders: Such as functional diarrhea, where diarrhea occurs without obvious pathology.
  • Endocrine Disorders: Thyroid disorders or diabetes impacting gut motility.

Management

  • Faeces for MCS: to establish the causative organism and antibiotic sensitivities.
  • Hydration and Electrolytes: Oral rehydration solutions or intravenous fluids in severe cases to prevent dehydration.
  • Dietary Adjustments: Bland diet initially; avoiding dairy, fatty foods, high sugar foods, and caffeine.
  • Medications:
    • Antidiarrheal Agents: Loperamide for symptom control but should not be used for bloody diarrhoea
    • Probiotics: For restoring gut flora, especially post-antibiotic diarrhea.
    • Antibiotics: For specific bacterial infections as identified by stool cultures.
      • Antibiotics should be avoided with E. coli 0157, Shigella or bloody diarrhoea.
  • Treating Underlying Conditions: Specific treatments for conditions like IBS, IBD, or thyroid disorders.
  • Avoiding Trigger Foods: For cases related to intolerance or allergy.
  • Surgical Intervention: In rare cases, such as for severe IBD or other structural problems.
  • Education and Counseling: For chronic conditions like IBS or celiac disease, patient education on diet and lifestyle adjustments is crucial.

Complications of infectious diarrhoea

  • Lactose intolerance (usually temporary)
  • Irritable bowel syndrome
  • Reactive arthritis
  • Guillain–Barré syndrome
  • Haemolytic uraemic syndrome (particularly when ABX are used with E.coli 0157 or Shigella)

Conclusion

Effective management of diarrhea requires a multifaceted approach, addressing the underlying cause, symptom relief, and prevention of complications like dehydration. Chronic or severe cases warrant a thorough diagnostic evaluation to guide specific treatments. Regular follow-up and lifestyle modifications play a significant role in managing chronic gastrointestinal conditions associated with diarrhea.