Persistent Diarrhoea In Children

Persistent diarrhoea is diarrhoea lasting 14 days or longer. It may follow an acute infection but persistence suggests ongoing enteric infection, postinfectious mucosal injury, malabsorption, nutritional deficiency or an underlying systemic disorder.

Important causes include Giardia, Cryptosporidium, persistent bacterial infection, HIV, tuberculosis, cow milk protein disease, coeliac disease, inflammatory bowel disease and severe malnutrition.

• Diarrhoea for at least 14 days
• Weight loss or poor weight gain
• Abdominal distension
• Reduced appetite
• Dehydration
• Perianal excoriation
• Signs of micronutrient deficiency
• Oral thrush, recurrent infection or lymphadenopathy where immunodeficiency is present

Blood, severe abdominal pain, oedema or marked wasting substantially increases concern.

• Assess hydration and nutritional status immediately.

• Send stool microscopy for ova, cysts and parasites where appropriate, particularly Giardia and Cryptosporidium, and bacterial culture or PCR when invasive infection is suspected.

• Test for HIV where status is unknown or clinical features suggest immunodeficiency.

• FBC, electrolytes, renal function and albumin help assess systemic effects.

• Consider coeliac serology, inflammatory markers and specialist gastrointestinal investigation when diarrhoea remains unexplained.

• Correct dehydration carefully and continue feeding.

• Continue breastfeeding.

• Provide energy dense, nutritionally complete feeds. Temporary lactose reduction can help when secondary lactase deficiency causes obvious worsening after milk intake.

• Treat a proven cause rather than using empirical antibiotics indiscriminately.

• Giardiasis: metronidazole 5 to 7.5 mg/kg PO three times daily for 5 to 7 days, or an appropriate tinidazole regimen where available.

• Correct zinc, vitamin and mineral deficiency and aggressively manage coexisting malnutrition.

• Persistent diarrhoea with severe malnutrition, dehydration, systemic illness or inability to feed requires inpatient treatment.