Diarrhoea

This is diarrhoea of sudden onset, often short-lived and is self-limiting. It requires no investigation or treatment. It is often seen after dietary indigestion. It may also be as a result of infections.

Acute diarrhoea in children

This is common of viral origin (e.g. Rotavirus, Norwalk virus, Adenoviruses or Enterovirus), but may also be caused by bacteria or other parasitic infections.

Clinical features

In addition to diarrhoea, there may be fever, abdominal pain and vomiting. If the diarrhoea is particularly severe, dehydration can be a problem.

With mild dehydration, there may be no signs. With moderate dehydration, the child may present with the following:

• Irritability, restlessness, sunken eyes
• Dry mouth and tongue, absence of tears
• Thirst
• Skin pinch goes back slowly

With severe dehydration, the child may present with:

• Lethargy or loss of consciousness
• Absence of tears
• Very dry mouth and tongue
• Thirst associated with poor drinking
• Skin pinch that goes back very slowly

Treatment

• Investigations are necessary if diarrhoea has lasted more than 1 week. In the meantime, supportive treatment should be given.
• Stools should be sent for microscopy and culture; any infective causes should be treated appropriately.
• Fluid management - See section on Cholera.
• In addition, the child should continue to feed on breast milk or other feeds.
• Anti-diarrhoeal drugs are not recommended.

Prevention:

• Acute Provision of clean water/sanitation
• Good disposal of faecal matter
• Boiling drinking water
• Chlorination of drinking water
• Personal hygiene - handwashing preferably with soap and running water after use of the toilet, when preparing food and before eating.

Diarrhoea in adults

Clinical features

In addition to diarrhoea, there may be fever, abdominal pain and vomiting. Dehydration can also be a problem if the diarrhoea is severe. This may be mild, moderate or severe in nature.

• Mild dehydration: The patient does not show enough signs to classify as moderate or severe dehydration.
• Moderate dehydration: The patient has two or more of the following signs:
  • Restlessness
  • Irritability
  • Sunken eyes
  • Dry mouth and tongue
  • Absence of tears
  • Thirsty, drinks eagerly
• Severe dehydration: The patient is classified as having severe dehydration if there are two or more of the following signs:
  • Lethargic or unconscious; floppy
  • Absence of tears
  • Very dry mouth and tongue
  • Very thirsty, drinks poorly or unable to drink
  • Pinched skin goes back very slowly

Other signs in adults and children above 5 years are absent radial pulse and low blood pressure.

Diagnosis

Investigations are necessary if the diarrhoea lasts more than one week, i.e. stool microscopy, culture and drug susceptibility.

Treatment

1. Fluid replacement
   Fluid therapy (see the section on Cholera)
2. Drug treatment
   In chronic diarrhoea and HIV-related diarrhoea where the cause has not been found:
   • Loperamide 2mg three times daily
   • Codeine phosphate 30mg four times daily

Any infective causes should be treated according to antimicrobial sensitivity patterns.

Prevention

As for acute diarrhoea in children.

This generally is diarrhoea lasting more than 2 weeks.

Causes include:

• Infections such as giardia, cryptosporidium, lsospora belli and microsporidia in AIDS patient.
• Colonic lesions such as carcinoma, Crohn's disease and ulcerative colitis
• Coeliac disease, Tropical sprue, Chronic pancreatitis
• Pseudo membranous colitis
• Thyrotoxicosis
• Diabetes

Clinical features:
Clinical features may include:

• Diarrhoea, bloody diarrhoea or steatorrhoea Abdominal pain and vomiting
• Weight loss
• Anaemia

Diagnosis Investigations:

• Stool microscopy, culture and sensitivity
• Special tests may be needed for certain parasites such as cryptosporidium, isospora and microsporidia
• Rectal/jejunal biopsy
• Barium enema
• Full blood count

Treatment: Treat infective causes of chronic diarrhoea.

1. Fluid therapy – Oral fluid use should be stressed except for patients presenting with severe dehydration in whom intravenous fluids should be used. However, even with severe dehydration, oral fluids should be given concurrently. Fluid management is as for cholera (See the section on Cholera).
2. Drug treatment - Antidiarrheal agents
   • Loperamide 2mg three times daily
   • Codeine phosphate 30mg four times daily
   • Nitazoxanide 100mg suspension;
     • Child 1 - 3 years 5ml twice a day with food for 3 days;
     • 4 - 11 years 10ml twice a day with food for 3 days;
     • 12 years and above, 500 mg tablets three times a day with food for 3 days.

Treat specific causes such as:

• Giardia – Metronidazole 400mg 8 hourly orally for 7 days
• Isospora Belli – Co-trimoxazole 960mg four times daily orally for 10 days. Give Pyrimethamine for sulpha-allergic patients. Recurrences tend to occur.
• Cryptosporidia – Albendazole 400mg twice daily orally for one month may help although combination antiretroviral therapy (cART) with immune reconstitution is the main line of management.

Prevention:

• As for acute diarrhoea.
• Prevention of HIV infection