Most diarrheal illness is due to infections which could be viral, bacterial, or parasitic infections. There are also non-infectious causes of childhood diarrhoea.

Acute watery diarrhoea in children less than 2 years is mostly caused by Rotavirus. In other age groups, the etiological agents of watery diarrhoea are Enterotoxigenic Escherichia coli (ETEC) which is common in older children and adults; Vibrio cholera O1 and O139 whereby the stool is like “rice-water" come as endemics or epidemics. Cryptosporidium is common in infants or HIV infected children. Noroviruses present with a sudden onset of vomiting and diarrhoea.

• Acute bloody diarrhoea or dysentery is often caused by Shigella spp that comes with epidemics and patients have severe disease with complications like sepsis, intestinal perforations, megacolon, rectal prolapse seizures and encephalopathy.
• Enteroinvasive Escherichia coli (EIEC) present with similar symptoms as Shigella.
• Enterohemorrhagic Escherichia coli (EHEC) is like Shigella, and patients have increased risk of developing haemolytic uremic syndrome.
• Nontyphoidal Salmonella enterica infection is common among infants, elderly and immunocompromised children. Campylobacter jejuni infection presents with diarrhoea in young children and acute mesenteric lymphadenitis in older children mimicking appendicitis. It could also lead to Guillain-Barré syndrome.
• Entamoeba histolytica a protozoon that is similar in presentation to Shigella and in rare cases lead till hepatic abscess
• Adenoviruses cause both watery diarrhoea and dysentery.

Non infectious causes of diarrhoea in children includes:

• Carbohydrate malabsorption (congenital or acquired)
• Functional diarrhea, eg, diarrhea-predominant irritable bowel syndrome, “chronic nonspecific diarrhea”
• Inflammatory bowel disease
• Pancreatic insufficiency
• Immunodeficiency syndromes
• Motility disorders
• Neuroendocrine tumours
• Hyperthyroidism
• Congenital diarrhoea
• Drug-related

Frequent stools more than 3 times daily or that which differs from the norm because breastfed children could have more stool. It can be watery or with blood.

1. Acute diarrhoea occurs within hours to days.
2. Persistent diarrhoea is more than 2 weeks
3. Severe malnutrition like kwashiorkor and marasmus with diarrhoea present even with severe systemic dehydration, vitamin deficiency and heart failure.

An important consideration in the management of a child with diarrhoea is the accurate assessment for dehydration. The degree of dehydration determines the urgency of the situation and the volume of fluid required for rehydration.

In the early stage of dehydration the child usually has no symptoms.

At the intermediate stage of dehydration: patient could be restless, thirsty or irritable. May have sunken eyes and fontanelle or decreased skin turgor when the abdomen is gently pinched, and it takes > 2 seconds to go back to its original level.

When the dehydration becomes severe, patients manifest with hypovolemic shock. There is reduced urine production, unconsciousness, cool clammy extremities, undetectable radial pulse and hypotonia.

Malaria: history of mosquito bite, fever. Bacterial meningitis: diarrhoea with fever and seizures Sepsis. Appendicitis. Intussusception. Hyperthyroidism. HIV. Neoplastic diseases. Milk intolerance is rare but should be suspected if stool increases as milk is given.

1. Initial evaluation includes electrolytes, BUN and creatinine. Electrolytes like sodium could be high when patient is given sweetened food or too concentrated formulas or fluid with too much salt. Hyponatremia (Sodium <130 mmol/l) if the child is given plain water or low salt. Hypokalaemia (Potassium <3mmol/l) occurs when the loss of potassium is not replaced during diarrhoea.
2. Stool specimen should be examined for mucus, blood, leucocytes and parasitic agents.
3. Faecal culture is recommended for patients with fever, profuse diarrhoea and dehydration or if HUS is suspected.
4. Full blood count

In children with mild to moderate dehydration it is important to give Oral rehydration therapy. Salted drinks like yoghurt, chicken soup, rice water can be given to children at home. Avoid sweetened drinks, carbonated drinks as it may lead to osmotic diarrhoea or hypernatremia. Coffee and medicinal teas should not be given because of their diuretic or purgative effects.

Weigh the child without clothes. There should be no delay in treatment of dehydration even if there is no weighing scale because an estimate of weight can be done using weight for the child’s age. A child with no dehydration an estimate of <5% of body weight and a fluid deficit of <50 ml/kg can be given. In moderate dehydration, 5-10% of body weight and an estimate of 50-100ml/kg. With severe dehydration a fluid deficit of >10% give a fluid of >100ml/kg.  A child showing sign of overhydration such as puffy eyes should not be given ORS nor diuretics but breastmilk.

Patients with severe dehydration start with intravenous fluids but give oral rehydration when stable. In severe dehydration 100 ml/kg Ringer Lactate whereby the first 30ml/kg is given within the first 1 hour for infants and 30 minutes for older children. The remaining 70 ml/kg should be given in 5 hours for infants and 2½ hours for older children.

An average of 75 ml/kg Ringer’s Lactate in 4 hours if a child with moderate dehydration persists in diarrhoea and have vomiting. In settings without intravenous fluid give ORS via a nasogastric tube 20 ml/kg/hour. If a child vomits or the abdomen distends give slowly and evaluate hourly

High nutritious foods given during and after diarrhoea reduce the risk of complications. It is important to give small amounts of staple food available in the environment as frequently as every 3-4 hours for infants and 1-2 hours in older children. Assessment of the patient every 15-30 minutes.

Zinc: Giving 10-20mg Zinc within the duration of diarrhoea or 10-14 days improve recovery of the intestinal mucosa and immune system. It could be given as a supplement

Antibiotics and antidiarrheal agents should not be routinely used. Antimicrobial could be given in suspected Cholera or Shigella (Ciprofloxacin). Loperamide can lead to abdominal distension. and paralytic ileus.

Antimicrobials that are ineffective for treatment of Shigellosis

• metronidazole • streptomycin · • tetracyclines · • chloramphenicol · • sulfonamides • amoxycillin • nitrofurans (e.g. nitrofurantoin, furazolidone) • aminoglycosides (e.g. gentamicin, kanamycin) • first and second generation cephalosporins (e.g. cephalexin, cefamandole Click here to enter text.

TREATMENT ALGORITHM FOR ACUTE INFECTIOUS DIARRHOEA.

Children with signs of dehydration should be followed up after 2 days and if not better referred to the hospital.

Parents should be educated about red flags in diarrhoea that should make them seek medical care immediately.

Breastfeeding

Sanitation: hand washing

Use of clean water

Food safety: Washing of hands before cooking. Heat food before eating. Proper cooking of food

Appropriate disposal of faeces

Immunization against rota virus infection.

Lactobacillus acidophilus – a probiotic- reduces the incidence of community acquired and antibiotic associated diarrhoea in children treated with oral antibiotics for other infectious diseases.