Acute Diarrhoea Management and Antidiarrhoeal Agents

Acute gastroenteritis is usually a mild, self-limiting illness in the UK. If prolonged and untreated there may be sequelae from dehydration and electrolyte disturbances. In Western Europe dehydration may necessitate hospital admission, but death is uncommon in the previously well.

Most cases are short-lived and do not require investigation.

General principles

• Assess dehydration and whether patient is systemically unwell
• Encourage fluids and rehydration
• Provide symptomatic relief with antimotility drugs
• Obtain stool sample if persists or food poisoning suspected
• Consider antibiotics if ill or frail
• Consider referring if very ill, diabetic on insulin or metformin

• People should be advised how to reduce spread by hand washing.² Disinfecting contaminated surfaces, prompt washing of soiled items and avoiding contaminated food or water are also recommended.
• Affected people should remain away from work or school until symptom free. Food-handlers and staff in health care services should be symptom free for 48 hours before return.³
• If diarrhoea is due to Hepatitis A then employees must remain off work for 7 days after the start of symptoms.
• Specialist advice should be sought for all cases of typhoid fever and haemorrhagic E. coli.
• Negative stool cultures are NOT prerequisite for return to work.
• Particular care should be taken when dealing with the following patients:
  • The very young or elderly
  • Those with co-morbidity e.g.diabetes, immunodeficiency, valvular heart disease, inflammatory bowel disease or gastric hypochlorhydria
  • Patients taking systemic corticosteroids, ACE-inhibitors, diuretics or acid suppressants.

General principles

Most people can be safely advised to increase their daily fluid intake during the episode of diarrhoea.

• Patients should be encouraged to drink glucose containing liquids and soups. Carbohydrates e.g. pasta and bread, assist the co-transport of glucose and sodium, so the amount of diarrhoea lost will be less than if water is used alone.
• Children and the elderly are prone to dehydration; the use of Oral Rehydration Therapy (ORT) is advisable.⁴
• A child should be encouraged by their preferred diet.

Management

• Dehydration of less than 5% (mild) can be treated in primary care.
  • The amount of weight loss as a percentage of normal body weight provides the best estimate of degree of dehydration.
  • Clinical signs are not present until the child has lost at least 4% of their body weight. The best signs for identifying dehydration include decreased peripheral perfusion, abnormal skin turgor, and an abnormal respiratory pattern.⁵
• ORT should be used in all cases where dehydration is seen.
  • Blood glucose monitoring should be more regular in diabetics on ORT.
  • Soft or fizzy drinks may cause osmotic diarrhoea as they are hypertonic.
  • 30-50 ml of ORT should be given to children over 3-4 hours.
  • If breast feeding is continuing, alternate feeds with ORT.
  • Adults should receive 2 litres of ORT in the first 24 hours. This is followed by unrestricted normal fluids with 200 ml of ORT for every loose stool or vomit.
• Moderate (5-10%) or severe (greater than 10%)dehydration is an indication for admission.

There is no evidence that fasting has any benefit to recovery. Normal feeding should be resumed as soon as possible.⁶ Most children with watery diarrhoea regain their appetite after dehydration is corrected, whereas those with bloody diarrhoea often eat poorly until the illness resolves.⁷

• Meta-analyses have found limited evidence that lactose-free feeds reduced the duration of diarrhoea in children with mild to severe dehydration compared with feeds containing lactose.⁸ A further Cochrane review is expected soon.
• Continuing to feed is particularly important during breast feeding.
• If the child is also vomiting, very small frequent feeds of normal diet or ORT every 10-60 minutes may be tolerated better.⁹

• In general there is a lack of evidence to support their use in primary care. There may be significant adverse effects in children.
• Adults may be helped, if vomiting is a severe problem, by metoclopramide 10 mg intramuscularly.

HPA and local microbiology departments prefer the avoidance of treatment in infective diarrhoea, unless absolutely necessary. Preferably the patient's own immune system should be allowed to cope, to avoid antibiotic resistance.

• Antibiotic therapy is usually only indicated for patients with positive stool cultures, who are systemically unwell and whose condition fails to improve within a few days.
• Empirical treatment may be justified in high risk groups or those with clinical picture of dysentery.
  • Ciprofloxacin 500 mg bd is appropriate.
  • A significant reduction in the duration of diarrhoea and other symptoms has been observed after treatment, regardless of whether a pathogen is detected.¹⁰
• It is also appropriate where symptoms cause serious disruption e.g urgent/ non postponable event.
• It is also appropriate in diabetic patients.
• Community acquired diarrhoea e.g. salmonella, responds well to ciprofloxacin, in cases where antibiotics are considered necessary. It reduces the duration of symptoms by 1-2 days.¹
• Trimethoprim is first line in children, adolescents, pregnant and breast feeding mothers.
• Prophylactic antibiotic prescriptions are NOT available on the NHS for foreign travel. It may be appropriate for patients travelling to remote areas to obtain a private prescription. A single 500 mg dose of ciprofloxacin is an effective empirical treatment for reducing the duration and severity of diarrhoea in travellers.¹¹

• These are occasionally useful for symptom control in mild to moderate diarrhoea in adults.
• They should be avoided if the diarrhoea is bloody as there is a risk of causing severe colitis and toxic dilation of the colon.^1,6
• Loperamide is first line treatment as it has fewer central nervous system adverse effects
• Anti-motility drugs are not to be used in young children. They do not prevent dehydration.
• Loperamide may be used in children aged over 4 years. Some evidence shows it significantly improved recovery time. It may cause constipation.⁸

• If symptoms have not settled within 48 hours, stool cultures for parasites, cysts and ova should be sent. Ideally 3 samples from differing days.
• History of recent foreign travel.
• Clinically indicated by severity of systemic upset, bloody diarrhoea, persisting for more than 5 days, suspected food poisoning or suspected traveller's diarrhoea.
• Check stool for Clostridium difficile if recently hospitalised or received broad-spectrum antibiotic therapy in previous 6 weeks.

• Patients who are more than 5% dehydrated. The amount of weight loss as a percentage of normal body weight provides the best estimate of degree of dehydration. Clinical signs are not present until the child has lost at least 4% of their body weight. The best signs for identifying dehydration include decreased peripheral perfusion, abnormal skin turgor, and an abnormal respiratory pattern.
• Severe systemic upset and unable to tolerate ORT
• The elderly
• Immunocompromised or taking systemic corticosteroids
• Typhoid syndrome
• Inflammatory bowel disease
• Pancreatitis, carditis or renal failure
• Specialist opinion should be sought if homosexual young men, or patients who are HIV positive develop acute, severe or persistent diarrhoea
• Chronic diarrhoea is defined as loose stools, with or without increased frequency for more than 4 weeks. Specialist opinion should be sought.