Malabsorption

We speak of malabsorption to indicate the insufficient passage of one or more products of digestion from the gastrointestinal tract to the blood.

Malabsorption, often associated with maldigestion, can be:

• selective (relative to a single nutrient, as in "lactose intolerance);
• partial (relative to a more or less large part of nutrients, as in a-Beta-lipoproteinemia (rare hereditary disease that interferes with the normal absorption of lipids);
• total (typical of celiac disease and other diseases or conditions that damage the mucous membrane of the small intestine).

Symptoms of malabsorption

Malabsorption should be suspected in the presence of chronic symptoms of deficiency of one or more nutrients, important and persistent alterations of the alvus (diarrhea, dysentery, steatorrhea), flatulence, meteorism, abdominal pain, weight loss, growth retardation in children and adolescents. , exhaustion and reduced exercise tolerance. These symptoms are then associated with those typical of the disease or condition that generated them (jaundice, gastritis, anemia, muscle cramps, edema, etc.); since many of these symptoms are non-specific, and as such common to various morbid forms with different etiopathogenesis, we generally speak of malabsorption syndromes.

Causes of malabsorption

The causes potentially responsible for malabsorption are many and rather difficult to classify. Some of these, such as abetalipoproteinemia, have family origins, while others are acquired (following infections, taking particular drugs, surgery, trauma, etc.). Among all, celiac disease is the hereditary disease most frequently associated with malabsorption , closely followed by cystic fibrosis.

Among the malabsorption syndromes of an infectious nature we remember traveler's diarrhea, intestinal flu, tropical sprue, enteric tuberculosis and intestinal parasites. Among those due to an enzyme deficiency, we remember the intolerance to lactose and other sugars such as fructose and sucrose; in this case the malabsorption has a predominantly genetic basis. Other possible causes of malabsorption include: imbalances of the intestinal bacterial flora (dysbiosis, bacterial contamination of the small intestine), Crohn's disease, ulcerative colitis, neoplasms of the digestive system, diseases of the pancreas (pancreatitis, pancreatic insufficiency), diseases of the liver and biliary tract (stones, liver failure, biliary atresia), damage caused by radiation therapy, gastrointestinal resection or bypass surgery (for example, to remove tumors or reduce food intake in the obese patient), overeating ( for example vitamin megadoses, surplus of bran and other dietary fibers, meals that are too abundant and varied), certain drugs or supplements (think for example of laxatives and anti-obesity drugs such as "orlistat and" acarbose), alcohol abuse, gastritis atrophic, hypochlorhydria / achlorhydria.

Malabsorption Diagnosis

On the basis of the observation of symptoms and individual medical history, the doctor prescribes the most suitable diagnostic investigations. For example, blood tests can highlight specific deficiencies, anemic forms, reduced blood clotting capacity, any alterations in liver and pancreatic function markers, or abnormal antibodies. The examination of the faeces allows to identify the causative agent responsible for the forms of infectious malabsorption, but also to quantify the levels of fat for the diagnosis of steatorrhea (lipid malabsorption) and those of chymotrypsin to evaluate pancreatic function. Invasive imaging and diagnostic techniques (barium enema, endoscopy, colonoscopy, biopsy of the intestinal mucosa, endoscopic retrograde cholangio-pancreatography, etc.) can be performed to highlight anatomical alterations of the various tracts of the digestive tract and biliary tract. To identify microbial alterations and enzymatic deficits responsible for malabsorption, so-called breath tests are performed.

Care and treatment

Cures and treatments obviously depend on the causes responsible for malabsorption. Specific food supplements may be required to fill nutritional deficits, which in the most serious cases will be performed by venous route (parenteral nutrition); in the presence of enzymatic deficiencies, the supplementation of animal (pancreatin) or vegetable (bromelain and papain) digestive enzymes may be useful; exclusion diets can be useful in the presence of food intolerances and celiac disease (avoiding, for example, foods that contain gluten); the use of antibiotics on the one hand and probiotics on the other can be useful to restore the normal balance of the intestinal flora in malabsorption syndromes due to or associated with dysbiosis.