This document provides an overview of approaches to evaluating and managing malabsorption syndromes. It discusses the etiology, pathophysiology, clinical features, diagnostic testing and general management strategies for a wide range of conditions that can cause malabsorption including celiac disease, short bowel syndrome, exocrine pancreatic insufficiency, bile acid malabsorption, infections, surgeries, and other disorders. The evaluation involves a detailed history, physical exam, initial lab tests, and may require endoscopic examination, imaging, and specialized tests of digestive and absorptive functions. Management is directed at the underlying cause, correcting nutritional deficiencies, and addressing symptoms.

1. APPROACH TO MALABSORPTION
SYNDROMES

2. MALABSORPTION
• Maldigestion
• Malabsorption
• Clinical presentation is similar.
• Even both doesn’t cover pathophysiological
spectrum of malabsorption syndromes.

5. ETIOLOGY & PATHOPHYSIOLOGY
• Mechanisms can be devided into
1)pre mucosal
2)mucosal
3)post mucosal
• It has limited clinical value

6. ABSORPTIVE MECHANISMS
• Solubilisation.
• Digestion.
• Liberation.
• Chemical changes.
• Intestinal sensory or motor function.
• Neuronal or harmonal functions.

8. FAT MALABSORPTION
• Defective mixing.
• Reduced solubilisation of fat.
• Decreased lipolysis.
• Decreased mucosal absorption and
chylomicron formation.
• Defective lymphatic transport of
chylomicrons.

9. PROTEINS & AMINO ACIDS
• Defective intraluminal proteolysis.
• Defective Mucosal Hydrolysis of Peptides and
Decreased Absorption of Oligopeptides and
Amino Acids

10. CARBOHYDRATES
• Defective Intraluminal Hydrolysis of
Carbohydrates.
• Mucosal Defects of Carbohydrate Digestion
and Absorption.

11. VITAMINS
• Fat soluble vitamins
• Water-Soluble Vitamins
1) vit B12.
2)Folic acid
3)other water soluble vitamins.

12. MINERALS
• Calcium.
• Magnesium.
• Iron.
• Zinc.
• Copper
• Other minerals

13. MECHANISMS THAT COMPENSATE
FOR MALABSORPTION
• Role of the colon.
• Role of Intestinal Transit in the Salvage of
Malabsorbed Nutrients

14. CLINICAL FEATURES AND
EVALUATION

15. History and Physical Examination

18. • Greasy stools may indicate fat malabsorption
or mucus in stools.
• Floating of stool in the toilet water.

19. Laboratory Findings
• blood tests-raise the suspicion of
malabsorption.
• stool tests -confirm that suspicion.
• Low levels of serum β-carotene, cholesterol,
triglycerides, and calcium and a prolonged
prothrombin time suggest malabsorption of
fat and fat-soluble vitamins.

20. Laboratory Findings
• Low levels of vitamin B12, folate, iron, and
albumin suggest malabsorption of water-
soluble substances.
• Low levels of plasma citrulline are associated
with destructive small intestinal disease (e.g.,
celiac disease) or can follow intestinal
resection

23. Diagnostic Approach

24. Clinical Clues to the Presence of
Specific Diseases
• h/o previous surgery.
• history of celiac disease
• history of travel
• alcohol consumption
• history of chronic pancreatitis or symptoms
pancreatic tumor

25. Clinical Clues to the Presence of
Specific Diseases
• clinical features of thyrotoxicosis, Addison’s
disease, Whipple’s disease, biliary or liver
disease, or diabetic neuropathy.
• diet high in poorly absorbable carbohydrates.
• likelihood of human immunodeficiency virus n
infection.
• treatment with a drug that can cause
malabsorption

26. Clinical Clues to the Presence of
Specific Diseases
• history of stem cell or organ transplantation or
abdominal radiation.
• history of extraintestinal manifestations of
inflammatory bowel disease, celiac disease, or
Whipple’s disease

29. • first-line tests.
• second-line tests.
• third-line tests.
• observation of the response to therapy

31. v

34. Anatomic Investigations
• Endoscopic examination and biopsy

39. Anatomic Investigations
• Video Capsule Endoscopy and
• Balloon Enteroscopy

43. Abdominal Imaging
• Small Bowel Follow-through and Small Bowel
Enteroclysis.
• Abdominal CT
• MRI of the Small Intestine
• US Examination
• Other Studies

45. WHIPPLES DISEASE

46. Noninvasive Evaluation of GI
Digestive
and Absorptive Function
• Fat Malabsorption
1) Quantitative Fecal Fat Analysis
2) Semiquantitative Fat Analysis
3) Qualitative Fecal Fat Analysis
4) Breath Tests for Fat Malabsorption
5) Serum Tests for Fat Malabsorption

47. Noninvasive Evaluation of GI
Digestive
and Absorptive Function
• Carbohydrate Malabsorption
1) The hydrogen breath test
2) lactose tolerance test
3) fecal pH
4) Total SCFAs and lactic acid

48. Noninvasive Evaluation of GI
Digestive
and Absorptive Function
• Protein Malabsorption
1) fecal nitrogen content
2) 14C-octanoic acid–13C-egg white breath
test &urinary output of phenol & p-cresol

49. Noninvasive Evaluation of GI
Digestive
and Absorptive Function
• Vitamin B12 (Cobalamin) Malabsorption
1) Schilling Test
2) Serum Test for Vitamin B12 and Folate
Deficiency

50. Noninvasive Evaluation of GI
Digestive
and Absorptive Function
• SIBO
1) the quantitative culture of a small intestinal
aspirate
2) deconjugated bile acids or vitamin B12 analogs
in intestinal aspirates
3) serum folate
4) breath tests(14C-glycocholate breath test, the
14C-dxylose breath test, the lactulose hydrogen
breath test, and the glucose hydrogen breath test.)

51. Noninvasive Evaluation of GI
Digestive
and Absorptive Function
• Exocrine Pancreatic Insufficiency
1) measurement of pancreatic enzyme,
volume, and bicarbonate output.
2) fecal chymotrypsin or elastase
concentration.
3) fluorescein dilaurate test.
4) (NBT-PABA) test
5) Secretin-enhanced MRCP

52. Noninvasive Evaluation of GI
Digestive
and Absorptive Function
• Bile Salt Malabsorption
1) Measurement of Fecal Bile Acid Output
2) 14Carbon-Taurocholate Bile Acid
Absorption Test.
3) Therapeutic Trial of Bile Acid-Binding
Resins.
4) Selenium-75-Labeled Homotaurocholic
Acid Test (SeHCAT

53. Noninvasive Evaluation of GI
Digestive
and Absorptive Function
• D-Xylose Test
• Intestinal Permeability Tests
• 13Carbon Breath Tests

54. Lactose Malabsorption
• Types
1)congenital
2)adult onset
3)acquired
• Clinical features
• Diagnosis
• Management.

55. Fructose Malabsorption
• Etiology
• Clinical features
• Diagnosis
• management

56. Bile Acid Malabsorption
• Etiology
• Compensated and decompensated
• Cholestyramine therapy
• mutations in the ileal sodium-bile
acid cotransporter gene (SLC10A2).

57. Amyloidosis
• Types causing amyloiosis.
• Pathology
• Factors causing diarrhoea & malabsorption.
• Clinical features.
• Diagnosis
barium studies
endoscpic features
histology
• Treatment

61. Gastric Resection or Bariatric Surgery
• Gastric resection
mechanisms
protein & fat malabsorption
hypovitaminosis E
vit B12 & iron Deficiency
calcium malabsorption
Treatment

62. Gastric Resection or Bariatric Surgery
• Bariatric Surgery
types

63. SHORT BOWEL SYNDROME

64. SHORT BOWEL SYNDROME
1. Loss of Absorptive Surface Area
• Nutrient Malabsorption
• Water and Electrolyte Malabsorption
• Loss of Site-Specific Transport Processes
• Loss of the Ileocecal Valve
• Loss of Site-Specific Enteroendocrine Cells
and GI Hormones
• INTESTINAL ADAPTATION TO RESECTION

65. MEDICAL MANAGEMENT
• MEDICAL MANAGEMENT
1. low-fat (40 g), high-carbohydrate diet
2. medium-chain triglycerides
3. Supplementation with vitamins, calcium, and
possibly magnesium

66. • Extensive Small Intestinal Resection and
Partial Colectomy
Fluid and Electrolyte
Diet
HOME PARENTERAL
NUTRITION

68. Connective Tissue Diseases
• Scleroderma
pathology
mechanisms
treatment
• Lupus Erythematosus and Other Connective
Tissue Diseases

69. Disaccharidase Deficiency and
Transport Defects
for Monosaccharides
• sucrase-isomaltase deficiency
• glucose-galactose malabsorption

70. Congenital Disorders of Lipid
Absorption
• Abetalipoproteinemia(MTP Gene)
• Familial hypobetalipoproteinemia(apo B)
• Chylomicron retention disease
• Anderson’s disease
• TREATMENT-replacement of triglycerides that
contain long-chain fatty acids with medium-chain
triglycerides and dietary supplementation with
tocopherol.

71. Congenital Disorders of Cobalamin
Absorption
• congenital cobalamin deficiency
• Imerslund-Graesbeck syndrome
• transcobalamin II deficiency,
• TREATMENT-All congenital disorders of
cobalamin absorption are treated by the
parenteral administration of cobalamin, although
high-dose oral cobalamin also might be effective.

72. Primary Immunodeficiency Diseases
• Selective Immunoglobulin A Deficiency
gluten-sensitive enteropathy
sprue-like small intestinal lesions
Pernicious anemia, giardiasis, and
secondary disaccharidase deficiencies
• Common Variable Immunodeficiency
respond to antimicrobial treatment &
glucocorticoids

73. Primary Immunodeficiency Diseases
• X-Linked Infantile Agammaglobulinemia
(Bruton’s Agammaglobulinemia)
• Immune Dysregulation-Polyendocrinopathy-
Enteropathy–X-Linked Syndrome (FOXP3)

74. • Neurofibromatosis Type 1 (von
Recklinghausen’s Disease)
• Nongranulomatous Chronic Idiopathic
Enterocolitis and Autoimmune Enteropathy

75. Endocrine and Metabolic Disorders
• Adrenal Insufficiency (Addison’s Disease)
associations
fat malabsorption
treatment

76. • Autoimmune Polyglandular Syndrome Type 1
etiology
mechanisms of malabsorption
endocrine system involved
diagnosis(staining and harmone levels)

77. • Hyperthyroidism
fat malabsorption
mechanisms
histopathology
increased prevalence of celiac disease
and PBC,
autoimmune gastritis

78. • Diabetes Mellitus
presents
mechanisms
celiac disease, SIBO, and pancreatic
insufficiency.
autoimmune atrophic gastritis

79. • Metabolic Bone Disease

80. GENERAL APPROACH TO
MANAGEMENT
• directed against the underlying condition if
possible.
• nutritional deficits must be corrected.
• In sugar malabsorption, diet with reduced
content of poorly absorbable carbohydrates is
an effective long-term therapy.
• Fermentable Oligosaccharides in patients with
symptoms of IBS.

81. GENERAL APPROACH TO
MANAGEMENT
• pancreatic insufficiency, disorders of intestinal
fat absorption, and short bowel syndrome,
medium-chain triglycerides can be used as a
source of dietary calories. diet rich in
carbohydrates and medium-chain
triglycerides.
• Teduglutide

82. GENERAL APPROACH TO
MANAGEMENT
• bile acid malabsorption-absorption can be
improved markedly by oral administration of
natural conjugated bile acids or synthetic
cholylsarcosine.
• special care should be given to the
replacement of vitamins, iron, calcium, and
trace elements to avoid deficiency syndromes

83. GENERAL APPROACH TO
MANAGEMENT
• symptomatic treatment with opiates or
loperamide can increase the time available for
absorption of nutrients.
• home parenteral nutrition-taurolidine.