Approach to diagnosis of patient with malabsorption : Approach to diagnosis of patient with malabsorption Seminar By Dr.Hariharan, 26.11.10
“Death sits in the bowels . . . Bad digestion is the root of all evil.”
Hippocrates, 400 B.C. What is “Malabsorption”? : What is “Malabsorption”? The integrated processes of digestion and absorption have 3 phases:
• Luminal phase
Disturbances of these processes lead to “malabsorption” Schematic representation of lipid digestion and absorption : Schematic representation of lipid digestion and absorption Individual diseases-Celiac Sprue : Individual diseases-Celiac Sprue Exposure to wheat, barley, or rye induces a characteristic mucosal lesion
E/O: Intestinal antigen-presenting cells in people expressing HLA-DQ2, or HLA-DQ8, bind with dietary gluten peptides in their antigen-binding grooves activate specific mucosal T lymphocytes cytokines mucosal damage.
Symptoms: spectrum asymptomatic to nutritional deficiencies weight loss, diarrhea, excess flatus, and abdominal discomfort
Diagnosis: IgA anti-tissue transglutaminase test (tTGA) or the IgA antiendomysial antibody test (EMA)
Treatment: Gluten free diet Lactose Malabsorption : Lactose Malabsorption E/O: deficiency of lactase
C/F: history of the induction of diarrhea, abdominal discomfort, and flatulence following the ingestion of dairy products
Diagnosis: The diagnosis is confirmed by the lactose breath hydrogen test.
An alternative is the oral lactose intolerance test.
Management: Lactose free diet Tropical sprue : Tropical sprue E/O: colonization of the intestine by an infectious agent or alterations in the intestinal bacterial flora induced by the exposure to another environmental agent ?
C/F: diarrhea, steatorrhea, weight loss, nausea, and anorexia, anemia,
Treatment: Tetracycline + folic acid Whipple’s disease : Whipple’s disease E/O: Tropheryma whipplei. Multi system involvement
increase in the frequency of HLA-B27
C/F: Weight loss, diarrhea, steatorrhea, and abdominal distention, arthritis, fever, nutritional def symptoms
Diagnosis: The diagnosis is established by demonstration of T.whipplei in involved tissues by microscopy
Treatment: Ceftrioxne 2weeks + septran 2 yrs Crohn’s Disease : Crohn’s Disease Crohn disease patients with extensive ileal involvement, extensive intestinal resections, enterocolic fistulas, and strictures leading to small intestinal bacterial overgrowth may develop significant and occasionally devastating malabsorption
C/F: Abdominal pain and diarrhea, Fever and weight loss, abdominal tenderness, most classically in the right lower quadrant
Diagnosis: barium imaging of small bowel mucosal disease, including strictures, ulcerations, and fistulae. CT, MRI
Colonoscopy- punched out lesions
Treatment: Sulfasalazine, ciprofloxacin, metronidazole, steroids, immunosuppresants Parasitic Infestations : Parasitic Infestations Giardia lamblia
Risk factors: travel to areas where the water sup-ply may be contaminated, swimming in ponds,
C/F: diarrhea, flatulence, abdominal cramps, and epigastric pain and nausea. Approximately one third of symptomatic patients experience vomiting. Significant malabsorption with steatorrhea and weight loss may develop
Lab: Stool examination for ova and parasites- 50%, three separate stool samples increases the yield of positive examinations to 80–90%.
Other parasites- coccidial, strongyloides Small Intestinal Bacterial Overgrowth (SIBO) : Small Intestinal Bacterial Overgrowth (SIBO) Diarrhea, steatorrhea(bacteroides deconjugate bile acids), and macrocytic anemia(B12)
E. coli or Bacteroides
E/O: diverticula, fistulas and strictures related to Crohn's disease , bypass surgeries functional stasis
Lab: low cobalamin and high folate levels
aerobic and/or anaerobic colonic-type bacteria in a jejunal aspirate obtained by intubation. Bacterial overgrowth is best established by a Schilling test
Treatment: surgical correction of an anatomical blind loop, tetracyclines- 2-3 weeks Protein-Losing Enteropathy : Protein-Losing Enteropathy group of gastrointestinal and non gastro intestinal disorders with hypoproteinemia and edema
increased protein loss into GIT
mucosal ulceration-ulcerative colitis, gastrointestinal carcinomas, and peptic ulcer
mucosal damage-celiac sprue and Ménétrier's disease
Diagnosis: peripheral edema and low serum albumin and globulin levels in the absence of renal and hepatic disease
alpha1-Antitrypsin can be used to document enhanced rates of serum protein loss into the intestinal tract
Treat the cause Approach to diagnosis-history : Approach to diagnosis-history Steathorrea Chronic pancreatitis Cystic fibrosis Surgery Cholecystectomy, resection Bloody diarrhea Large volume Arsenic, drugs, bowel resection, crohn’s, carcinoid, gastrinoma Radiation IBD, eosinophilic gastroenteritis, immunodef + pain, fever Lactase def Osmotic + low pH Chronic diarrhea Crohn’s Slide 18: 1)anemia, dermatitis herpetiformis, edema ulcerative colitis dermatitis herpetiformis IBD 2)abdominal mass or tenderness erythema nodosum Flushing Carcinoid celiac disease 4)mucocutaneous manifestations Edema ptn losing enteropathy 3)Flatus undigested CHO 6)amenorrhea, infertility, and impotence due to malnutrition Clinical examination 5)Manifestations of vitamin and mineral deficiencies Xeropthalmia, glossitis, purpura, tetany, peripheral neuropathy etc Initial tests : Initial tests Stool
Sudan stain, quantitative determination-48hrs-fat
Cck-secretin stimulation test- pancreatic insufficiency
Stool samples should be evaluated for ova and parasites and for specific parasitic antigens in patients with suspected malabsorption
Elastase, chymotrypsin, pH(<5-5 in CHO malabsorption)
CBC, complete metabolic profile (including liver enzymes), albumin, total protein, cholesterol, triglycerides, iron studies.
B12, folic acid, ESR/CRP, TSH,
Esophagogastroduodenoscopy with small intestinal biopsies
Abdominal ultrasound Slide 20: The Schilling Test-
This test is performed to determine the cause for cobalamin malabsorption.
Since cobalamin absorption requires multiple steps, including gastric, pancreatic, and ileal processes, the Schilling test can also be used to assess the integrity of these other organs
Achlorhydria, Bacterial overgrowth syndromes
administering 58Co-labeled cobalamin orally and collecting urine for 24 h. Urinary excretion of cobalamin will reflect cobalamin absorption Urinary D-Xylose Test : Urinary D-Xylose Test The urinary D-xylose test for carbohydrate absorption provides an assessment of proximal small-intestinal mucosal function.
D-Xylose, a pentose, is absorbed almost exclusively in the proximal small intestine. The D-xylose test is usually performed by giving 25 g D-xylose and collecting urine for 5 h. An abnormal test (<4.5 g excretion) primarily reﬂects the presence of duodenal/jejunal mucosal disease. Radiologic Examination : Radiologic Examination Normal individual.
Jejunal diverticulosis(blind loop)
Crohn's disease. Biopsy of Small-Intestinal Mucosa : Biopsy of Small-Intestinal Mucosa RESULTS OF DIAGNOSTIC STUDIES IN DIFFERENT CAUSES OF STEATORRHEA : RESULTS OF DIAGNOSTIC STUDIES IN DIFFERENT CAUSES OF STEATORRHEA Second line tests : Second line tests Sigmoidoscopy, colonoscopy, ERCP
Esophagogastroduodenoscopy with small intestinal biopsies
immunoglobulins, human immunodeficiency virus antibodies, antinuclear antibodies, ferritin, food allergen-specific IgE, adrenocorticotropic hormone, cortisol, chromogranin A, gastrin, urinary 5-HIAA
Quantitative fecal fat Third line tests : Third line tests MRI
Somatostatin (octreotide) scan
Enteroscopy, including biopsies
Spiral CT of the pancreas for tumor
Tests for bile acid malabsorption
Glucagon, somatostatin in serum/plasma References : References Harrison’s internal medicine
Current diagnosis and treatment in gastroenterology
Pubmed.com Thank you : Thank you