GI - Pathology (Malabsorption syndromes) Flashcards
Pg. 353 in First Aid 2014 Sections include: -Malabsorption syndromes
What are 5 signs/symptoms that malabsorption syndromes can cause?
Can cause (1) diarrhea, (2) steatorrhea, (3) weight loss, (4) weakness, and (5) vitamin and mineral deficiencies; Think: “These Will Cause Devastating Absorption Problems”
To what other condition does Tropical sprue have similar findings? How is it different?
Similar findings as celiac sprue (affects small bowel), but responds to antibiotics
What is the cause of Tropical sprue? In patients with what exposure/history is it seen?
Cause is unknown, but seen in residents of or recent visitors to tropics
What pathogen causes Whipple disease? What is its Gram stain?
Infection with Tropheryma whipplei (gram positive)
What are 3 key histologic findings of Whipple disease?
(1) PAS (+) (2) foamy macrophages in intestinal lamina propria, (3) mesenteric nodes
What are 3 common symptoms of Whipple disease?
(1) Cardiac symptoms (2) Arthralgias and (3) Neurologic symptoms are common.; Think: “Foamy (macrophages) WHIPPed cream in a CAN”
In what patient population does Whipple disease most often occur?
Most often occurs in older men
What defines celiac sprue?
Autoimmune-mediated intolerance of gliadin (wheat) leading to malabsorption and steatorrhea
With what 2 HLA markers is Celiac sprue associated? With what ethnicity is it associated?
Associated with HLA-DQ2, HLA-DQ8, and northern European descent
What are 6 histologic/lab/clinical findings that characterize Celiac sprue?
Findings include (1) anti-endomysial, (2) anti-tissue transglutaminase, and (3) anti-gliadin antibodies; (4) blunting of villi; and (5) lymphocytes in lamina propria. (6) Decreased mucosal absorption that primarily affects distal duodenum and/or proximal jejunum
What is used to diagnose Celiac sprue?
Serum levels of tissue transglutaminase antibodies are used for diagnosis
With what skin condition is Celiac sprue associated? What kind of risk does Celiac sprue increase? Give an example of this risk.
Associated with dermatitis herpetiformis; Moderately increased risk of malignancy (e.g., T-cell lymphoma)
How is Celiac sprue treated?
Treatment: gluten-free diet
What is the most common disaccharidase deficiency, and what effect does it have?
Most common is lactase deficiency => milk intolerance
Describe the key histologic finding in disaccharidase (lactose) deficiency. What is its major symptom?
Normal-appearing villi. Osmotic diarrhea.
Where in the intestine is lactase located? Give this, how can self-limited lactase deficiency occur?
Since lactase is located at tips of intestinal vili, self-limited lactase deficiency can occur following injury (e.g., viral diarrhea)
What test is used for lactase deficiency? What are 2 criteria for determining that a patient is positive for lactase deficiency?
Lactose intolerance test: (+) for lactase deficiency if: (1) Administration of lactose produces symptoms and (2) Glucose rises < 20 mg/dL
What is the pathophysiology of Abetalipoproteinemia, and what effect does it have?
Decreased synthesis of apolipoprotein B => inability to generate chylomicrons => decreased secretion of cholesterol, VLDL into bloodstream => fat accumulation in enterocytes
When does Abetalipoproteinemia present, and what are 5 of its signs/symptoms?
Presents in early childhood with failure to thrive, steatorrhea, acanthocytosis, ataxia, night blindness
What are 3 causes of pancreatic insufficiency?
Due to cystic fibrosis, obstructing cancer, and chronic pancreatitis
What effects does pancreatic insufficiency have?
Causes malabsorption of fat and fat-soluble vitamins (vitamins A, D, E, K)
What stool finding is associated with pancreatic insufficiency?
High neutral fat in stool
What clinical test is relevant to pancreatic insufficiency? What kind of result is expected with pancreatic insufficiency? In what other contexts/conditions is this result different?
D-xylose absorption test: normal urinary excretion in pancreatic insufficiency; decreased excretion with intestinal mucosa defects or bacterial overgrowth
