Digestion and Absorption Disorders Flashcards
Malabsorption Syndromes
- Pancreatic Insufficiency
- Bile Salt Deficiency
Pancreatic Insufficiency
- lack of pancreatic digestive enzymes
- lipase
- amylase
- trypsin
- chymotrypsin
Causes of Pancreatic Insufficiency
- Pancreatitis
- Pancreatic Carcinoma
- Pancreatic Resection
- Cystic Fibrosis
Primary Problem of Pancreatic Insufficiency
- Fat maldigestion
Most common signs of Pancreatic Insufficiency?
- Fatty Stools (steatorrhea)
- weight loss
Treatment of Pancreatic Insufficiency
- Lipase supplements
Bile Salt Deficiency
- Poor intestinal absorption of lipids
Bile salt deficiency caused by
- liver disease
- bile obstructions
Most common signs of bile deficiency
- fatty stools
- diarrhea
- loss of fat-soluble vitamins (A,D,E,K)
Bile Salt Deficiency treatment
- increase medium-chain triglyercides (MCFA-MCT-oil) in diet
- Parenterally administer fat soluble vitamines A,D,E,K
General Symptoms of Fat Malabsorption
- steatorrhea
- foul stools
- flatulence
- abdominal distension
- abdominal cramping
- Diarrhea: irritating products of colonic bacteria
- SCFA (small chain fatty acids) stimulate colonic crypt Cl- secretion
- Diarrhea: >100/250mL of water/liquid per day in stool
- Fat malnutrition:
- weight loss
- fatigue
- neuropathy
- nervous tissue composed of fat
Fat soluble Vitamin Deficiency Symptoms:
- A
- night blindness
- D
- osteopenia
- osteoporosis
- rickets
- E
- capillary fragility
- bruising
- bleeding
- stress
- K
- clotting disorders
- bleeding
- anemia
Diagnosis of Fat Malabsorption:
- Confirmation test:
- fecal fat test
- normal: <7g/day
- fecal fat test
- Determine cause: includes general malabsorption
- imaging:
- endoscopy of upper GI
- barium contrast may detect disease
- endoscopy of upper GI
- Blood tests
- Vitamins A, D, E, & K
- Iron/Hct/RBCs
- Vitamin B12
- Folate
- Fectal tests
- fecal elastase
- for pancreatic insufficiency
- Fecal osmotic gap:Osmolarity
- >100=osmotic diarrhea
- malabsorption
- <50=secretory Diarrhea
- solutes are ions
- due to colonic secretions
- >100=osmotic diarrhea
- fecal elastase
- Provacative/Functional Tests
- imaging:
Diagnosis of Fat Malabsorption: Provacative Malabsorption Tests
- Bile salt absoprtion
- measure absorption of radiolabeled bile salts
- low absorption=damage to terminal ileum or chemical interference (ex: lipid lowering drugs)
- Schilling Test
- measure radiolabelled B12 absorption
- If low repeat with intrinsic factor
- if absorption low in both, cause=terminal ileum
- absorption is low w/o IF=gastric
- D-xylose
- Transported by SGLT1 but not metabolized
- measure in urine over several hours
- low=intestinal disease
- celiac, Crohn’s
Fat Malabsorption: Gastric Causes
Etiology
- Gastric Insufficiency from disease process
- gastritis
- Reduced and delayed emulsification
Fat Malabsorption: Gastric Causes
Severity and Symptoms
- Severity:
- Moderate fat malabsorption
- Symptoms:
- Odorous stools
- flatulence
- abdominal cramps
- fecal incontenence
- Deficiencies in B12 or iron
- not A, D, E, K
Fat Malabsorption: Gastric Causes
Diagnosis
- Schilling test
- Anemia Tests
Fat Malabsorption: Gastric Causes
Treatment
- Treat underlining causes/condtions
- Decrease dietary fat intake
- increase small meal frequency
Fat Malabsorption: Liver/Gallbladder
etiology
- Reduced bile salts and phospholipids
Fat Malabsorption: Liver/Gallbladder
Severity and Symptoms
- Severity:
- moderate
- Symptoms:
- Odorous stools
- flatulence
- abdominal cramps
- fecal intolerance
- fat souble vitamin deficiency syndromes
Fat Malabsorption: Liver/Gallbladder
Treatment
- Treat underlying causes
- decrease fat intake
- increase small meal frequency
- Dietary Ursodeoxycholic acid (non-detergent bile salt)
Fat Malabsorption: Intestinal
Etiology
- Reduced absorption
- usually intestinal disease or short bowel syndrome
- other genetic or acquired casues
Fat Malabsorption: Intestinal
Severity and Symptoms
- Severity:
- variable depending on disease
- Symptoms:
- Fat, carbohydrate, protein or vitamin deficiency
Fat Malabsorption: Intestinal
Treatment
- Treat undelrying causes/condition
- parenteral nutrition
Fat Malabsorption: Other causes
- Lymph Obstruction (Lymphangiectasia)
- Cellular Processing
- Other
- MCFA enter by gap juncitons
Lymph Obstruction
- Aka lymphangiectasia
- tumor or other growth
- wilson/parasite disease
- typically presents w/fat malabsorption
- Biopsy
- chylomicrons in lamina propria
Cellular Processing
- Genetic Lesions to:
- golgi
- ER
- chaperone proteins
- cytoskeleton
- transport proteins
- apoproteins
- B lipoprotein (most common)
- exocytosis
- Biposy:
- fat in organelles or accumulated chylomcrons
Fat Malabsorption: Other causes
Treatment
- Treat underlying condition
- MCFA
- parenteral nutrietion or diet
Carbohydrate Intolerance
etiology
- Enzyme deficiencies
- Congenital
- rare
- lactase or sucrase
- Acquired
- primary adult hypolactasia
- use it or loose it phenomenom
- Secondary
- mucosal damage
- celiac
- crohns
- mucosal damage
- Congenital
Disaccharidase Deficiencies
- Lactose Intolerance
- lactase=inducible enzyme
- neonatal and adults forms
- 37% of US population is lactase deficient
- Tx: Abstinence
- Sucrose Intolerance
- 1 in 10,000
- tx: avoid sucrose (cane or beet sugar)
Carbohydrate: Transport Deficiencies
- Fructose intolerance
- Deficient GLUT5
- most common monosaccharide malabsorption syndrome
- Symptoms:
- Like lactose intolerance
- Tx:
- reducing fructose or adding glucose or sucrose
- Deficient GLUT5
- Other:
- Lack of Na-glucose cotransporter-1 (SGLT1)
- tx: substitute fructose for glucose
- Lack of Na-glucose cotransporter-1 (SGLT1)
Protein Digestion Disorders
- Pancreatic Insufficiency
- Gastric Disorder
- Amino Acid transport disorder
