Malabsorption syndrome refers to a number of disorders in which the intestine can’t adequately absorb certain nutrients into the bloodstream. It can impede the absorption of macronutrients (proteins, carbohydrates, and fats), micronutrients (vitamins and minerals), or both.
Proteins, carbohydrates, fats, and most fluids are absorbed in the small intestine (small bowel). Malabsorption syndrome occurs when something prevents the bowel from absorbing important nutrients and fluids. The problem may be caused by inflammation, intrinsic disease, or injury to the lining of the intestine. Sometimes, the condition may be the result of the body’s failure to produce enzymes needed to digest certain foods or to adequately mix the food with the enzymes and acid produced by the stomach.
Factors that may affect the digestion of food and cause malabsorption syndrome include:
- prolonged antibiotic use
- other conditions such as celiac disease, Crohn’s disease, chronic pancreatitis, or cystic fibrosis
- lactase deficiency, or lactose intolerance, which is fairly common in people of African or Asian descent and happens when the body lacks the enzyme needed to digest lactose, a sugar present in milk
- congenital (birth) defects, such as biliary atresia, which is when the bile ducts don’t develop normally and may become blocked and prevent the flow of bile from the liver
- diseases of the gallbladder, liver, or pancreas
- damage to the intestine (from infection, inflammation, trauma, or surgery)
- parasitic diseases
- radiation therapy (which may injure the mucosal lining of the bowel)
There are some fairly uncommon disorders that result in malabsorption. One possibility is short bowel syndrome. This condition may be a birth defect or the result of surgery. The surface area of the bowel decreases, and this hinders the bowel’s ability to absorb nutrients.
Another disorder that may lead to malabsorption is tropical sprue. This condition is most common in Southeast Asia, the Caribbean, and India. Its symptoms may include anemia, diarrhea, sore tongue, and weight loss. The condition may be related to environmental factors, such as toxins in food, infection, or parasites.
An even more rare possibility is Whipple’s disease, which usually affects middle-aged men. The condition may be caused by a bacterial infection. A key symptom is crampy abdominal pain. Additional symptoms include:
- chronic fever
- darkening of skin pigment
- joint pain
- weight loss
Symptoms of malabsorption syndrome are caused by the passage of unabsorbed nutrients through the digestive tract. They will be different depending on the specific nutrient or nutrients that are not properly absorbed. Other symptoms are caused by a deficiency of that nutrient in the body:
- If you have a fat deficiency, you may have light-colored, foul-smelling stools that are soft and bulky. Stools are difficult to flush and may float or stick to the sides of the toilet bowl.
- If you have a protein deficiency, you may experience fluid retention (edema), dry hair, or hair loss.
- If you have a sugar deficiency, you may have bloating, flatulence, or explosive diarrhea
- If you have a vitamin deficiency, you may have anemia, malnutrition, low blood pressure, weight loss, and muscle wasting.
Children with malabsorption syndrome may avoid certain foods. They may also fail to grow properly. Their weight or rate of weight gain may be significantly below that of other children of a similar age and gender.
Risk factors for malabsorption include:
- excessive alcohol consumption
- a family history of cystic fibrosis or malabsorption
- intestinal surgery
- use of certain medications including laxatives or mineral oil
- travel to Southeast Asia, the Caribbean, and India
A doctor may suspect malabsorption syndrome if the patient suffers chronic diarrhea, nutrient deficiencies, or has significant weight loss despite eating a healthy diet. Laboratory tests are used to confirm the diagnosis. These tests may include:
Stool tests measure fat in stool samples. These tests are the most reliable because fat in the stool is usually present in this disorder.
These measure malabsorption of specific nutrients such as vitamin B-12, vitamin D, folate, iron, calcium, carotene, phosphorus, albumin, and protein. A deficiency in one of these vitamins may not necessarily mean that you have malabsorption syndrome. Normal levels of these nutrients suggest that malabsorption is not the problem.
Breath tests are used to test for lactose intolerance. If lactose is not being absorbed, bacteria in the colon will use the lactose to produce hydrogen gas. The patient then exhales the gas. The presence of hydrogen gas in the breath after ingesting a product containing lactose means that you may have intolerance to lactose.
A biopsy is used if an abnormality in the bowel lining is suspected.
Nutrient and fluid replacement are the first step in treating malabsorption syndrome. Specific treatment will depend on the cause. For example, if you are found to have lactose intolerance, you should avoid milk and other dairy products or take a lactase enzyme tablet. Hospitalization may be required in the most extreme cases.
If you have been diagnosed with malabsorption syndrome, you should consult with a dietician to make sure you are getting proper nutrients. You should eat several small meals throughout the day that are rich in carbohydrates, fats, minerals, proteins, and vitamins. You will be monitored for signs of dehydration, which may include dizziness or weakness, dry mouth, skin or tongue, increased thirst, and low urine output.