Dysentery

What is dysentery?

Dysentery is a condition characterised by inflammation in the colon, which causes frequent and poorly formed stools with mucus and blood. Dysentery is of two types: bacterial dysentery wherein the causative microorganism is a bacterium, such as Shigella or Eisherichia coli (E. coli) and amoebic dysentery where the causative organism is a protozoan Entamoeba histolytica (E. histolytica).

What are its main signs and symptoms?

Dysentery occurs commonly in unhygienic or low sanitation conditions, especially in rural India and slum areas of urban India. The disease is marked by intermittent constipation and watery stools. The symptoms that one might commonly experience are

• Watery or poorly formed stool
• Occurrence of mucous and blood in stool
• Pain while passing stool
• Fever
• Nausea
• Increased frequency of passing stools

Dysentery is often misunderstood or confused with diarrhoea. However, the latter is caused by toxins released from certain infective agents, and although the patients pass poorly formed stools in both the diseases, they are not full of mucus or blood in diarrhoea.

If the disease is not treated, colonic perforations leading to ulcers in the colon may be observed in some cases.

What are its main causes?

The disease occurs due to consumption of drinking water and food which is contaminated by infected faecal matter containing the microbes. Depending on the type of contamination, dysentery can be of two types:

• Bacterial Dysentery – It caused by bacteria E.coli or four different species of Shigella
• Amoebic Dysentery – It caused by protozoan E. histolytica (Read more: Amoebiasis treatment)

In both types of diseases, the infection spreads by

• Drinking infected water
• Non-maintenance of hygiene before eating
• Eating infected food
• Having oral or anal sex with an infected person

How is it diagnosed and treated?

The diagnosis is made by some simple laboratory tests, such as

• Stool examination and its microbial culture
• Immunochromatographic dipstick technique
• Endoscopy, in case the passage of blood in stool continues

WHO has provided clear guidelines for treating dysentery as it occurs as an epidemic during the rainy season in the months of May to October in India:

• Rehydration to make up the loss of water and electrolytes (Read more: How much water to drink in a day)
• Antibiotic treatment to eliminate the bacteria
• Antiprotozoals to avoid protozoa infection

Generally, 5-8 days of treatment should be sufficient to manage the symptoms. Prolonged use of antibiotics without a doctor’s advice can lead to drug resistance. The medication is uncostly and the treatment is not painful. Some self-care and preventive tips can help you avoid further recurrence:

• Following healthy eating habits
• Washing hands before meals
• Avoiding defecation in the open
• Drinking boiled and cooled water

Conclusively, dysentery, although a commonly occurring disease, can be controlled by following hygienic lifestyle, healthy eating habits, and proper medication.

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