Diarrhoea: Incidence, Causes, Symptoms, Diagnosis, and Treatments
What is Diarrhoea?
Diarrh0ea is the condition in which they is increased passage of loose or watery stools relative by anorexia to the person’s usual bowel habit. It may be associated by anorexia, nausea, vomiting, abdominal cramps or bloating. It is not a disease but a sign of an underlying problem such as an infection or gastrointestinal disorder. The most likely cause of diarrhoea in all age groups is viral or bacterial infection; therefore it can be associated with other conditions, for example, irritable bowel syndrome, inflammatory bowel disease, colorectal cancer and malabsorption syndromes.
Incidence Rate of Diarrhoea
In children leads to high consultation rates with primary care doctors and accounts for one in five consultations in the 0–4 age group. It has been estimated that children under the age of 5 years have between one and three bouts of diarrhoea per year. The incidence of diarrhoea in adults is, on average, just under one episode per person each year. Many of these cases are thought to be food related, with 22% of those consulting a doctor claiming to have
‘food poisoning’. Traveller’s diarrhoea is another common cause of diarrhoea.
What are the Causes of Diarrhoea
Rotavirus and small round structured virus (SRSV) are the most common identified causes of gastroenteritis in children. In adults, Campylobacter followed by rotavirus are the most common causes, although rates of norovirus have reported to be on the increase. Other identified causes include: the bacteria E. coli, Salmonella, Shigella, Clostridium perfringens enterotoxin; viruses such as adenovirus and astrovirus; and the protozoa Cryptosporidium, Giardia and Entamoeba histolytica. So-called traveller’s diarrhoea frequently affects people travelling from an area of more developed standards of hygiene to a less developed area. In many instances, the cause remains unknown, even after stool culture, but where a pathogen is identified, bacterial infection is responsible in over 80% of cases, and associated with ingestion of contaminated food or water and occurs during or shortly after travel. Bacterial pathogens commonly isolated include E. coli, Shigella, Salmonella, Campylobacter, Vibrio and Yersinia species.
Viruses (10–15% of cases) and parasites (2–10% of cases), such as norovirus,Giardia, Cryptosporidium and Entamoeba, account for the remainder.
Signs and Symptoms of Diarrhoea
Acute-onset diarrhoea is accompanied with loose or watery stools which is associated with anorexia, nausea, vomiting, abdominal cramps, flatulence or bloating. When there is blood in the diarrhoea this is classed as dysentery and indicates the presence of an invasive organism which include Campylobacter, Salmonella, Shigella or E. coli. The history of symptom onset is important. The duration of diarrhoea, whether other members of the family and contacts are ill, recent travel abroad, food eaten, antibiotic use and weight loss are all important factors to elucidate. Dehydration is a common problem in the very young and frail elderly and the signs and symptoms must be recognised.
In children, the severity of dehydration is most accurately determined in terms of weight loss as a percentage of body weight prior to the dehydrating episode. Unfortunately, in the clinical situation pre-illness weight is rarely known; therefore, clinical signs of dehydration must be assessed. Symptoms that could indicate mild dehydration are vague and include tiredness, anorexia, nausea and lightheadedness. Symptoms become more prominent in moderate dehydration and include dry mucous membranes, sunken eyes, decreased skin turgor (pinch test of 1–2s or longer), tachycardia, apathy, dizziness and postural hypotension. In severe dehydration, the above symptoms are more marked and may also include hypovolaemic shock, oliguria or anuria, cold extremities, a rapid and weak pulse and low or undetectable blood pressure.
Diagnosis for Diarrhoea
Before any investigations are undertaken a medication history is required to eliminate antibiotic- and other drug-induced diarrhea, or the possibility of a laxative overuse-induced diarrhea. Testing for C. difficile-induced pseudomembranous colitis is indicated in those with severe symptoms or where hospitalisation or antibiotic therapy with lincomycins, broad spectrum β-lactams or cephalosporins has occurred within the preceding 6 weeks. In general, stool culture is required in patients who are immunocompromised, with bloody diarrhoea, severe symptoms, where there is no improvement within 48h. Stool culture is also required when there is a history of recent overseas travel to non-Western countries. Where the diarrhoea persists for more than 10 days, further investigation should be undertaken to exclude parasites such as Giardia, Entamoeba and Cryptosporidium. Acute, severe or persistent diarrhoea in a homosexual male or patient with AIDS warrants referral for specialist advice.
Treatment for Diarrhoea
Depending on the causative agent, a number of complications may have to be dealt with.
- Patients should be advised on handwashing and other hygiene-related issues to prevent transmission to other family members.
- Exclusion from work or school until the patient is free of diarrhoea is advised.
- In acute, self-limiting diarrhoea, children, health care workers and food handlers should be symptom free for 48h before returning to school or work.
- In both children and adults, normal feeding should be restarted as soon as possible. In weaned and unweaned children with gastroenteritis, early feeding after rehydration has been shown to result in higher
weight gain, no deterioration or prolongation of the diarrhoea and no increase in vomiting or lactose intolerance.
- Similarly, breastfeeding infants should continue to feed throughout the rehydration and maintenance phases of therapy. Avoidance of milk or other lactose-containing food is seldom justified.
Dehydration Treatment for of Diarrhoea
- Since diarrhoea results in fluid and electrolyte loss, it is important to ensure the affected individual maintains adequate fluid intake.
- Most patients can be advised to increase their intake of fluids, particularly fruit juices with their glucose and potassium content, and soups because of their sodium chloride content.
- High-carbohydrate foods such as bread and pasta can also be recommended because they promote glucose and sodium co-transport.
- Young children and the frail elderly are prone to Diarrhoea induced dehydration and use of an oral rehydration solution (ORS) is recommended.