Friday, May 31, 2013

Diarrhoea and Oral Rehydration Therapy

Diarrhoea or acute gastroenteritis is a universal problem. The most frequent cause of acute gastroenteritis is an infection of the intestines. Such an infection results in an outpouring of fluid and electrolytes (sodium, potassium, chloride and bicarbonate) from the intestinal epithelial cells into the intestinal lumen, which is then purged out as diarrhoeal stool. Diarrhoea has been defined as passing of three or more loose or watery stools in a day. If there is vomiting along with loose stools; loss of large amount of body water and salts is imminent and would lead to dehydration. Infants and young children develop dehydration faster than adults especially in hot climates, when diarrhoea is also associated with fever. So the most significant harmful effect of diarrhoea is major loss of fluid and electrolytes. However during the infective diarrhoea the intestinal ability to absorb of glucose, salts, water and nutrients remain well preserved. Since the absorptive ability of intestines is not altered by diarrhoea, so the management of diarrhoea or acute gastroenteritis is possible with oral rehydration therapy (ORT).

For ORT, a standard solution of oral rehydration salts (ORS) prepared under the recommendations of World Health Organization (WHO) is administered through mouth in small amounts (50 to 100 ml) depending on the age of patient at regular intervals of time. For preparing a standard solution of ORS, the powder is dissolved in known quantity of boiled cooled or purified drinking water as mentioned on the packet of ORS. With oral rehydration therapy the death rate of people dying of severe dehydration due to diarrhoea has significantly come down and the requirement of intravenous drips has become almost negligible.

A packet of ORS contains 27.5 grams of essential salts to be dissolved in a litre of boiled cooled or purified drinking water. An ORS packet contains 20 grams of glucose, 3.5 grams of sodium chloride (common salt or table salt), 2.5 grams of sodium bicarbonate (backing soda) and 1.5 grams of potassium chloride. Packets of ORS are supplied free of cost at Primary Health Centers and Government Hospitals and dispensaries. Low salt content home-made fluids are equally good in emergency if a packet of ORS is not available immediately. Children with diarrhoea should be treated with ORS without loss of time.

The solution of ORS should be kept covered and used within 20 hours. If need be, fresh ORS solution should be prepared after 20 hours. Adults and older children should drink as much as they like from a cup or tumbler of ORS. A child under two years of age should be given half to one cup of ORS solution after each stool to compensate the loss of water and salts. Older children and adults should drink at least one to two cups after each stool. Easily digestible solid food such as boiled rice, soups, porridge, banana shake, curd, eggs, fish and well cooked meat are allowed even during diarrhoea. Treatment in hospitals and health centers depends on the degree of dehydration and other complications like fever and shock.

Monday, May 27, 2013

Potato & Mushroom Poisoning

If you study the botanical origin of potato, you would find that it belongs to the group of plants, the stems and leaves of which contain toxic agents termed as solanines. The botanical name of potato is Solanum tuberosum and it belongs to the family Solanaceae. Solanines are known to cause poisoning in cattle eating the potato plant. The tuber (potato) itself also contains small amounts of poisonous material called solanines in its peels. You must have seen that storage of potatoes leads to greening and sprouting. Both these processes lead to the production of poisonous material around the 'sprouting eyes' and also inside the flesh of potatoes. Sprouting and green potatoes taste bitter due to the presence of solanines and should not be consumed. Sometimes, people who are unaware of the poisonous nature of green and sprouting potatoes; eat these and develop poisoning symptoms. The onset of potato poisoning symptoms occurs some 4 to 12 hours after its consumption. The abdominal pain, vomiting and diarrhoea are predominant symptoms of potato poisoning. Mild headache and fever have also been reported in some cases. Severe potato poisoning may also lead to a state of coma.

Be cautious while eating potato products. The treatment of potato poisoning is always symptomatic; loss of fluids and electrolytes have to be replaced orally with oral rehydration powder dissolved in water or intravenously in cases of severe dehydration. Use of antibiotics should be avoided in known cases of potato poisoning. An average general practitioner may miss the diagnosis of potato poisoning and pass of the case as a common case of 'gastroenteritis'. The potato poisoning may be severe form of food poisoning in students eating midday meal from the common kitchen at schools, as the kitchen staff generally overlook the quality of potatoes received by them.

Mushroom poisoning is also presented with abdominal pain, vomiting and profuse diarrhoea after latent phase of around 12 hours or more. Severe mushroom poisoning may also lead to liver and kidney failure within 3 to 4 days after the development of vomiting and diarrhoea. Some of the mushrooms, e.g. Amanita phalloides are so poisonous that consumption of one mushroom is sufficient to cause severe poisoning and three mushrooms could be considered a fetal dose. With the cultivation of mushrooms being taken up by the trained personals, the cases of mushroom poisoning have come down. Only those who collect and eat wild mushrooms fall prey to mushroom poisoning due to lack of knowledge about the identifying features of poisonous mushrooms. Knowledge is the key to care and maintenance of health. Never eat green or sprouting potatoes and wild mushrooms to save yourselves from potato poisoning or mushroom poisoning.

Saturday, May 25, 2013

Cholera: Prevention is better than cure

Cholera is a diarrhoeal disease caused by the bacteria known as Vibrio cholerae. The infection leads to a form of diarrhoea in which the patient passes the so called rice-water stool instead of the usual formed faeces. The cause of such stools is now well understood. On entering the human intestine through contaminated food or water, the Vibrio cholerae lodges itself in small intestine. Here it secretes certain proteinaceous substances (known as enterotoxins), which attach to the specific receptors (Gm ganglioside)on the intestinal cell surface. A part of enterotoxin then enters the intestinal epithelial cells and activates the metabolic pathway in them leading to a profuse outpouring of fluids from them into the intestinal lumen. The bacteria themselves, however, do not invade the tissue. The disease had been endemic in India down the centuries, mainly in the Ganges and Brahmputra deltas in Bengal. The record of spread of Cholera throughout the world is available only after 1817 when the first pandemic occurred.  Since then six such pandemics are on record showing that the disease affected millions of people all over the world with high rate of mortality and morbidity. The seventh pandemic spread from the Sulwesi Island in Indonesia in 1961 that was caused by a biotype el Tor of Vibrio cholerae.

The man is the only source of the disease. The spread occurs through a contaminated environment. An infected patient excretes around 107 to 102 bacteria per ml of stool which may further contaminate drinking water through sewage pollution. Wells and reservoirs of surface water (lakes and ponds) can get contaminated easily.  Food is another source of infection. All people in the endemic area should use boiled cooled water for drinking. Food handlers can also act as transmitters of infection. Flies act as mechanical transmitters of Cholera infection. Sanitation staff should be alerted to decontaminate the water-bodies with permitted chemicals.

The clinical picture may range from an asymptomatic carrier state to the fulminant disease. The most characteristic feature is rice-water stool and a precipitate vomiting. Dehydration may develop due to fluid loss and if not treated, the patient may collapse within 24 hours. Tentative diagnosis of disease can be made by the microscopic examination of stool, where a hanging drop preparation on a slide would show darting mobility of the bacteria. The specific diagnosis is made by growing the bacteria on artificial media in the laboratory and by serotyping of bacterial colonies grown on media.

The disease is treated by replacing the lost fluids and electrolytes, intravenously if the patient is admitted to a hospital or orally through oral rehydration powder. Tetracycline is the drug of choice. Sulphonamides, furazolidne and cotrimethoxazole have also been found to be useful. Drugs should never be taken without medical consultation. Cholera is one of the diseases which can be prevented by vaccination controlled by sanitation. The source of infection being man alone and the commonest vehicle of transmission is the water. Special attention should therefore be paid to the purity of water and the ice made from it for human consumption. The disposal of human excreta and garbage should be safe and soiled clothes of the patient must be disinfected. The isolation and treatment of Cholera patients is must. The outbreak of cholera should be notified at national level immediately for adequate prophylactic vaccination of people traveling to that area. The cholera vaccine (vaccine developed from attenuated Vibrio cholerae) is given by intramuscular injection provides effective protection for two to three months in around 89% of vaccinated population. However, oral vaccines of cholera are also available with variable protective efficacy.