(1) General. Dysentery is the term applied to a number of intestinal disorders (especially of the colon) that are characterized by inflammation of the mucous membranes. It is a common disease that is often self-limiting and mild but can be serious for babies up to 3 years old. A rise in strains of dysentery which are resistant to multiple antibiotics has been noted recently.

(2) Signs and symptoms. Dysentery usually begins abruptly and the patient has diarrhea, and suffers lower abdominal cramps and tenesmus. Blood and mucus are often found in the diarrheal stool. Other symptoms include fever (up to 104ºF in young children), chills, headache, and lethargy. Meningismus, coma, and convulsions occur in the most severe cases. Dehydration, weakness, and a tender abdomen follow as the illness progresses. In infants, dehydration, acidosis, and electrolyte imbalance occur.

(3) Treatment. The antibiotic of choice is ampicillin (100 mg/kg/d) which can be given for 5 to 7 days orally in 4 divided doses. If there is improvement, do not continue with the medication any longer even if the stool cultures are still positive. Other medication effectively used in treating dysentery are tetracycline, chloramphenicol, or co-trimoxazole. Actually the use of even mildly toxic antibiotics is usually not justified because the majority of cases are mild and self-limited. For all moderately or severely ill patients, parenteral hydration and correction of acidosis and electrolyte disturbances are a necessity. Give clear fluids for 2 or 3 days after the bowel has been at rest for a short time and offer the patient small frequent feedings with a diet that is soft and easily digestible. Whole milk, high residue, and fatty foods should be avoided. If cramps are severe, anti-spasmodics (i.e., tincture of belladonna) may be helpful. Place the patient on effective stool isolation precautions to limit the spread of infection.

b. Cholera.

(1) General. Cholera is an acute bacterial diarrheal disease of the small intestine. Cholera is caused by Vibrio cholerae which are transmitted by food or drink that is contaminated by feces containing a large number of vibrios. These vibrios produce a powerful exotoxin in the small intestine (in particular, the ileum) where they grow. The reduction of the sodium reabsorption causes massive diarrhea that is fatal in 50 percent of cases if untreated. This exotoxin induces hypersecretion of water and chloride in the small bowel.

(2) Signs and symptoms. Cholera victims experience a sudden onset of painless, watery diarrhea of up to 15 liters per 24 hours. The liquid stool is grayish containing mucus and food particles. There is no fecal odor, blood, or pus, but rapid dehydration takes place. The patient may have occurrences of vomiting and becomes markedly dehydrated and acidotic. His eyes are sunken and he experiences intense thirst, hypotension, a subnormal temperature, oliguria, shock, muscle cramps, and coma.

(3) Treatment. The loss of water and electrolyte must be restored immediately and continuously, and acidosis must be corrected. Replacement of oral fluids (same volume as that lost) may be possible in the moderately ill patients. If the patient is unable to take fluids by mouth, an I.V. infusion of Ringer's lactate must be used to replace the fluids until the blood pressure and circulating blood volume are restored. The medication used to suppress vibrio growth and shorten the time of vibrio excretion is tetracycline, 0.5g given orally every 6 hours for 3-5 days. If untreated, cholera lasts 3-5 days and has a mortality rate of up to 80 percent. If the victim receives prompt and competent treatment, however, the mortality rate can be reduced to 1 percent. The health department must be notified if it is suspected that a victim has cholera.

(4) Prevention. The cholera vaccine consists of 2 injections of 0.5 and 1 ml. intramuscularly or subcutaneously 1-4 weeks apart, then a booster dose of 0.5 ml is administered every 6 months when cholera is a hazard. Even so, the vaccine offers only limited protection and has no value in controlling outbreaks. All water, other drinks, food, and utensils must be boiled or avoided in endemic areas. When high standards of sanitation and public health exist, there is rarely an outbreak of cholera of any significant size.

c. Typhoid Fever.