GI Flashcards
GERD
-most common disorder in esophagus
-endoscopy with biopsy for dysphagia
-H2RA/PPI/AA
H. Pylori Diagnostics / TX
- Biopsy (culture, urease enzyme activity detection)
- C-breath test
- Immunoassay for IgG antibody (may remain positive for years even after successful treatment)
PPI with 2: amoxi, clari, metro, or MTPB
All major phases of absorption may simultaneously be affected, i.e. fats, proteins, carbohydrates, vitamins, minerals, etc. This syndrome called general malabsorption is characterized by
amylorrhea (excess starch), steatorrhea (excess fat), and creatorrhea (meat fibers, protein)
General Malabsorption/Maldigestion May Be Due To:
- Pancreatic disease
- Zollinger-Ellison syndrome
- Liver disease
- Intestinal disease (CD/CD)
- Resin tx
PIZLR
Tests of nonspecific biochemical abnormalities seen in malabsorption
- Low Ca < 8.5
- High alk phos > 129
- Low urea nitrogen < 6
- Hypocholesterolemia (normal chol is < 200)
- Prolonged prothrombin time
- Flat glucose tolerance curve
CCAPN
Specific malabsorption/maldigestion defects
- Disaccharidase deficiencies:
-lactase deficiency
-sucrase deficiency
-maltase deficiency - Glucose-galactose malabsorption
- Pernicious anemia
- Protein-losing enteropathy
- Blind-loop syndrome
- Jejunal diverticulum
- Parasitic infestations
JP is a BD so he goes to GAP
Carbohydrate malabsorption
-D-xylose absorption test (decreased)
-Disaccharidase test (decreased)
-Breath hydrogen test (increased)
Fat malabsorption
-Fecal fat determination (elevated)
-14C-triolein breath test (decreased)
Bacterial overgrowth
14C-Xylose breath test (increased)
Other tests in malabsorption/digestion:
Schilling test will be ___
Sweat test will be ___
- Decreased
- Increased in cystic fibrosis
Celiac Disease
- Gluten in the patient’s diet at the time of testing for IgA endomysial ab (EMA) against transglutaminase
- Positive = bowel biopsies
- Diagnosis confirmed with resolution of sx after cutting out gluten
*in celiac disease but IgA deficient = need total IgA quantitation and IgG antibodies to tissue transglutaminase testing
ABSORPTION OF VITAMIN B12 AND PERNICIOUS ANEMIA
-Suspicion of pernicious anemia (macrocytic anemia) can be confirmed by measuring autoantibodies against intrinsic factor
-Diagnosis can also be confirmed by parenteral administration of B12 with resolution of sx
Schilling Test for Vitamin B12
-orally administering 57Co-radiolabeled B12 and quantitating its appearance in urine
-reference population excretes > 8% of the ingested dose in a 24 hour urine collection while < 7% is excreted in pernicious anemia
-if abnormality corrects with the co- administration of intrinsic factor with B12, the defect is due to deficiency of intrinsic factor rather than malabsorption due to pancreatic or ileal causes
SWEAT TEST FOR THE DIAGNOSIS OF CYSTIC FIBROSIS
-In cystic fibrosis, sweat chloride values are 60-120 mmol/L; normal values are < 60 mmol
-Only acceptable test is the sweat test done by iontophoresis with direct determination of chloride or sodium
*Normal Cl < 60, Na 10-90
*Elevated in CF: Cl 60-120, Na 60-180 (overlap = less useful)
Black, tarry stools
-Drugs (such as salicylates, steroids, reserpine, indomethacin, colchicine, iron, CRISSI) often cause increased gastrointestinal blood loss, resulting in positive occult blood tests
-False neg: ascorbic acid (NA)
-False pos: horseradish (peroxidase) (PH)
