Tropical sprue
Tropical sprue is a digestive system disorder primarily affecting individuals in tropical regions, characterized by severe diarrhea, intestinal irritation, and malabsorption of nutrients, leading to malnutrition. The condition is believed to be triggered by an infectious organism in the intestines, though the exact cause remains unclear. Common symptoms include pale, oily, and foul-smelling stools, abdominal discomfort, weight loss, and fatigue. Diagnosis typically involves blood tests for nutrient levels, stool tests for fat absorption, and imaging studies to assess intestinal damage. Treatment often includes a combination of antibiotics, such as tetracycline or Bactrim, and nutritional supplements to address deficiencies. While the prognosis with appropriate treatment is generally positive, children may experience more severe complications, including growth delays and dental issues, necessitating careful management. Awareness and timely medical intervention are crucial for those affected, especially in endemic areas such as Southeast Asia and the Caribbean.
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Tropical sprue
Tropical sprue is a relatively rare disorder of the digestive system. A person with the condition experiences severe diarrhea and intestinal irritation and has difficulty absorbing nutrients, minerals, and water, resulting in malnutrition. The disease is most likely caused by an infectious organism in the intestines, and as the name implies, it mostly affects people who live in or visit tropical regions. There is no known way to prevent the disease, but it can be treated with a combined therapy of folic acid and the antibiotic tetracycline. While there are some possible complications, especially in children who contract the disease, the prognosis with treatment is generally good.
Background
The condition known as tropical sprue was first identified in 1759 by William Hillary, an English doctor who had a special interest in tropical diseases. In that year he published a book, Observations on the Changes of the Air, and the concomitant Epidemical Diseases in Barbados, with a Treatise on the Bilious Remittent Fever, which contained the first description of this specific disease. It was later confirmed that the disease existed in other parts of the world besides Barbados.
A sprue is a medical condition in which the intestines' ability to absorb nutrients from food is impaired. The word sprue comes from a Dutch word for an inflammation of the mouth, which is one of the signs of the condition Hillary observed. While the condition can occur in any tropical area, it is most often found in people who live or travel for longer than a month in Southeast Asia, southern India, and the Caribbean. It is most commonly reported in Puerto Rico and the Dominican Republic. It is rarely seen in the United States and is growing rarer in other parts of the world as well, possibly because of the use of antibiotics to treat the condition known as "traveler's diarrhea" before it has a chance to progress to a point where food absorption is affected.
Overview
The exact cause of tropical sprue is unknown. It is believed that some microbe, possibly coliform bacteria, irritates the intestines and sets off a reaction of increasing irritation. Eventually, this reaches a point where the person's intestines are damaged and can no longer effectively process several key nutrients, including folic acid and vitamin B12. This results in a deficiency that triggers megaloblastic anemia, a blood disorder in which there are fewer red blood cells than the body needs to transport oxygen effectively. The lack of oxygen causes some of the symptoms of tropical sprue, while others are due to the inflammation and resulting inactivity of the intestines.
Symptoms of tropical sprue include severe diarrhea with stools that are pale, oily, unformed, and foul smelling, as well as abdominal gas, fatigue, loss of appetite, weight loss, and weakness. The diarrhea may be chronic or acute, and may result in severe stomach cramps. The condition can develop gradually or suddenly. It may be accompanied by a high fever, irritation of the mouth and tongue that gave it the name "sprue," and dry skin. In some cases, the disease prompts depressive symptoms in the patient as well.
Although the disease can sometimes go away on its own in what is known as spontaneous remission, the patient with tropical sprue will most likely require treatment with medication. There are no definitive diagnostic tests or procedures to identify tropical sprue, but physicians can look for several indicators. These include blood tests to measure the presence of certain nutrients, such as iron, folate, vitamin B12, and vitamin D; a stool test to see how well the intestines are processing fats; and a test called D-xylose, which measures the intestines' ability to process sugar. The physician may also order tests to examine the intestines for damage. These may include an enteroscopy, which uses a tube inserted into the mouth or rectum to access the intestines; an upper endoscopy, which uses a lighted tube to examine and sometimes take samples of internal tissue; or an upper gastrointestinal (upper GI) series, in which the patient is x-rayed after drinking a special beverage containing barium, a substance that helps the physician see the action of the esophagus, stomach, and intestines.
Diagnosis is sometimes made by elimination. If a patient with digestive symptoms like those of tropical sprue has been tested for other conditions with negative results and has had exposure to a tropical region, tropical sprue may be suspected. In either case, the treatment is the same.
Treatment starts with alleviating the symptoms. The patient is given fluids and drugs to combat diarrhea, as well as supplements of folic acid, iron, and vitamins to replenish those lost to malabsorption. The patient will also be given a course of antibiotics, most commonly tetracycline or Bactrim. It may be necessary for the patient to take the antibiotics for three to six months to fully heal the intestines and return the digestive system to full normal function. However, the treatment generally works with few if any long-term effects, and the patient's overall prognosis is very good. The notable exception is in children. While children get the condition less frequently than adults do, it can cause longer-lasting conditions in children, including growth failure or delay due to the malnutrition that accompanies the illness. In addition, children whose permanent teeth have not come in must be treated with a different antibiotic, as tetracycline causes irreparable damage to developing teeth.
Bibliography
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