Malabsorption Syndrome


  • It’s a group of disorders related to the involvement of the small intestines in absorbing nutrients, vitamins, and trace elements. In its broad sense, this term also includes malabsorption syndrome – a disorder of digestion.

Causes of Malabsorption:

  • Primary cause: related to genetic and congenital disorders in the structure of the small intestines and fermentopathies.
  • Secondary cause: appears in cases of acquired diseases.
  • Originating from the intestines (organic and functional).
  • Pancreas (chronic pancreatitis, pancreatic cancer).
  • Stomach (atrophic gastritis, gastric resection, gastrinoma, gastric cancer).
  • Liver (cholestatic liver disorders, large bowel syndrome).

Small Intestine Diseases (Intestinal Damage):

  1. Gluten enteropathy (celiac disease).
  2. Crohn’s disease.
  3. Whipple’s disease.
  4. Diverticulosis (diverticular disease).
  5. Tumors, lymphomas of the small intestines.
  6. Small intestine resection, fusions.
  7. Infectious and parasitic diseases of the small intestines (tuberculosis, giardiasis, whipworm disease, ascariasis, tapeworm disease, trichuriasis, salmonellosis), small intestine inflammation by northeastern severity.
  8. Toxins (heavy metals, alcohol, uremia).
  9. Hypothetical: drug-induced (nonsteroidal anti-inflammatory drugs, antibiotics, antacids, cytostatics, corticosteroids, laxatives), radiation therapy.
  10. Sensitivity to small intestinal damage.
  11. Hormonal intestinal damage (hyperthyroidism, hypothyroidism, diabetes, Addison’s disease, deficiency of the pituitary gland hormone, APUD system tumors).
  12. Immunodeficiency conditions (gluten enteropathy, AIDS).
  13. Hemodynamic dynamics (decreased mesenteric blood flow, severe right ventricular failure).
  14. Functional diseases of the small intestines (hypothetical and secondary to enzyme disorders, different motilities).
  15. Systemic diseases (amyloidosis, systemic scleroderma).

According to the nature of the lesion:

  • Partial (selective) absorption.
  • Complete absorption.
    According to the severity of the condition:
  • Mild (Grade I).
  • Moderate (Grade II).
  • Severe (Grade III) Depending on the deficiency of body mass index and the severity of general symptoms.

Biological Pathway of Malabsorption Syndrome:

  • Damage or decrease in the absorption surface of the small intestines (organic diseases of the small intestines).
  • Disturbance in the absorption capacity of the small intestines:
  • Digestive system disorders due to lack of stomach and small intestinal enzymes, acceleration in motor activity, pancreas, and gallbladder disorders.
    Disorders within the intestines in malabsorption syndrome:
  • Morphological changes in the mucous membrane (atrophic-degenerative changes in the mucous membrane, shortening and flattening of the villi).
  • Disturbance in the operation of enzyme and transport systems in the small intestines.
  • Disorders in motor function.
  • Development of bacterial overgrowth syndrome in the small intestines.
  • Development of diarrhea (type of excessive water intake).

General Disorders in Malabsorption Syndrome:

  • Protein and fat malabsorption, carbohydrates, vitamins, trace elements, and bile acids.

    Disorders in all types of exchanges: protein, fat, carbohydrate, water-electrolyte, mineral, vitamin, hormonal.
    Clinical symptoms (digestive disorder):
  • Diarrhea with the formation of excessive stool (stool mass exceeding 300 grams per day).
  • Abdominal pain syndrome.
  • Intestinal discomfort (bloating, rumbling, gas bloating).
    Clinical signs of the appearance of intestinal malabsorption syndrome:
  • Weight loss (in children – delay in growth and dwarfism).
  • Bleeding syndrome.
  • General anemia syndrome.
  • Iron deficiency syndrome.
  • Electrolyte imbalance syndrome (calcium deficiency, potassium deficiency, sodium deficiency, magnesium deficiency).
  • Vitamin deficiency.
  • Protein energy malnutrition syndrome.

Types of Diarrhea:

  1. Secretory Diarrhea – Increased secretion of water and electrolytes in the lumen of the small intestines.
  • Passive secretion when hydrostatic pressure increases in the blood vessels of the small intestines (lymphoma, amyloidosis detachment in the intestines, Whipple’s disease, severe right ventricular failure).
  • Active secretion when activating the adenylate cyclase-cAMP system (infections, bile acid, laxatives, pancreatic secretions, serotonin, bacterial overgrowth syndrome).

Osmotic Diarrhea – Decrease in water and electrolyte absorption:

  • Malabsorption syndrome (disorders in the oral and membrane digestion).
  • Consumption of salt laxatives, sorbitol.
  1. Exudative Diarrhea – Discharge of water, electrolytes, and plasma protein through the damaged mucous membrane of the intestines:
  • Exudative enteropathy, vascular diseases in the intestines, intestinal tumors, Crohn’s disease, salmonellosis.

Hypermotility Diarrhea:

  • Neural stimulation (functional motor disorders, diabetic enteropathy).
  • Hormonal stimulation (serotonin, gastrin, secretin).
  • Drug-induced (laxatives, magnesium-containing antacids).
Diagnosis of Malabsorption Syndrome:
  1. Clinical blood analysis: Microcytic and macrocytic anemia; there may be an increase in leukocyte count and erythrocyte sedimentation rate (in lymphoma and Crohn’s disease), decrease in lymphocytes count (in exudative enteropathy), increase in eosinophil count (in allergic enteropathy).
  2. Biochemical blood analysis: Disorders in protein, fat, carbohydrate, and electrolyte exchange.
  3. Coagulation test: Decrease in prothrombin and fibrinogen.
  4. Determination of vitamin B12 levels, folic acid, iron, ferritin in the blood.
  5. Glucose tolerance test: Acute glycemic curve.
  6. Complete urine analysis: Presence of oxalates in urine, in severe malabsorption syndrome – reduction in daily urine excretion.
  7. Hormonal tests: Decrease in T3, T4, cortisol, TSH, sex hormones. In case of intestinal tumors – increase in serotonin and histamine.
Immune tests:
  • Blood test for tissue transglutaminase antibodies, endomysium antibodies, gliadin – for celiac disease diagnosis.
  • pANCA, ASCA – for diagnosing spiral diseases.
  • Immunogram – decrease in all classes of antibodies – in case of exudative enteropathy, spiral diseases.
  1. Blood analysis tests: Beet reactions with Yersinia antigen, tuberculin, and Salmonella – PCR for parasites.
  2. Ultrasound and sonography.
  3. Digestive methods: Examination of the esophagus, stomach, duodenum with targeted biopsy sampling from the distant section of the small intestines, and if necessary – with targeted biopsy sampling from the thin small intestines, video capsule endoscopy, colonoscopy with biopsy sampling from the soft intestines.
  4. Histological analysis of the small intestines’ mucous membrane.
  5. X-ray examination of the intestines using barium sulfate (diagnosis of Crohn’s disease, typhoid fever, diverticulosis, tumors, deformities, and congenital deformities).
  6. CT, MRI (diagnosis of tumors, peritoneal inflammation).
  7. Duplex scanning and angiography of the legs and abdominal arteries.

Principles of Malabsorption Syndrome Treatment:

  1. Treatment of the underlying disease condition.
  2. Therapeutic nutrition.
  3. Improvement of digestion and absorption processes in the small intestines (alternative treatment with enzymes and correction of absorption function).
  4. Treatment of diarrhea and improvement of intestinal motility function.
  5. Treatment of bacterial overgrowth disorders and restoration of normal bacterial balance in the intestines.
  6. Improvement of the mucous membrane condition in the small intestines (use of inhibitory, absorbing, and coating substances).
  7. Correction of metabolic and electrolyte disorders, treatment of anemia, vitamin deficiencies, and pituitary gland disorders.