Endocrine/Metabolism/GI Flashcards
Vitamin A Overdose
-acute- N/V, vertigo, blurred vision
chronic- alopecia, dry skin, hyperlipidemia, hepatotoxicity, hepatosplenomegaly, visual difficulties, papilledema/cerebral edema
teratogenic- microcephaly, cardiac anomalies, fetal death
Vitamin B1 Deficiency
- thiamine
- infantile and adult beriberi (dry with peripheral neuropathy or wet with cardiac sx)
- Wernicke-Korsakoff syndrome in alcoholics
Vitamin B12 Deficiency
- cobalamin
- pernicious anemia
- presentation: older, mentally slow women of northern Euro descent who is lemon colored (anemic and icteric), and has a smooth/shiny tongue indicative of glossitis w/ shuffling, broad based gait
Vitamin B3 Deficiency
- Niacin
- 3 Ds of pellagra: dementia, dermatitis, diarrhea
Vitamin C Overdose
- false negative stool guaiac results
- diarrhea, abdominal bloating
Vitamin E Overdose
-higher mortality rate due to hemorrhagic stroke in adults and higher rates of necrotizing enterocolitis in infants
Vitamin B2 Deficiency
- riboflavin
- cheilosis (cracks at corners of mouth), stomatitis, glossitis, dermatitis, corneal vascularization, and ariboflavinosis
Cholecystekinin
- stimulates digestion of fat and protein
- secreted by I cells in duodenum
- causes secretion of digestive enzymes from pancreas and gall bladder contraction
Gastrin
- released by G cells
- stimulates HCl secretion by promoting histamine release
Somatostatin
- hormone that inhibits gastrin release
- secreted by delta cells
- raises pH in duodenum
Indirect Indicators (Labs) of Chronic EtOH Consumption
- macrocytosis (vitamin/folate deficiency)
- AST:ALT ratio >2
GLUT4
- transmembrane glucose transport protein
- responsive to insulin
- expressed in skeletal muscle cells and adipocytes
- provides facilitated diffusion of glucose across membrane
- steroselective for D-glucose
GLUT2
- present in hepatocytes (liver), pancreatic B cells, renal tubules, small intestine
- provides facilitated diffusion of D-glucose across membrane
GLUT3
-present in placenta and neuronal cells
Amylase
- secreted by parotid gland
- hydrolyzes starch into sugars
- elevated in acute bacterial parotits (caused by Staph a.)
Chymotrypsin
- secreted by pancreas
- inactive precursor is chymotrypsinogen
- activated by trypsin
Phospholipase A2
- can damage cell membranes
- secreted by pancreas as inactive precursor prophospholipase A2
- activated by trypsin
Elastase
- secreted by pancreas
- inactive precursor is proelastase
- activated by trypsin
Trypsin
- activates chymotrypsin, phopholipase A2, carboxypeptidase, and elastase
- inactive form is trypsinogen
- inappropriate activation is a central path to necrotizing pancreatitis
- converted to trypsin by enteropeptidase (enterokinase)
Lipase
-converts triglycerides to fatty acids and glycerol
Wilsons Disease
- AR WD gene mutation in copper transporting ATP-ase
- kayser fleischer ring on eye
- basal ganglia atrophy
- disorder of copper metabolism causing liver disease
- dx: dec. serum ceruloplasmin and inc. tissue copper levels
- tx: D penicillamine or trientine, transplant is curative
C Peptide
Released with endogenous release of insulin. Will not be present of insulin supply is exogenous.
Elevated alk phos… What now?
Test for gamma glutamyl transpeptidase. If high, this indicates hepatic issue, but if low, this indicates bone issue.
Secretin
Secreted by duodenal S cells and inc. bicarbonate secretion from the pancreas.
Small intestine bacterial overgrowth is associated with increased:
Vitamin K and folate (because these are made by gut bacteria)
Budd Chiari Syndrome
Thrombotic occlusion of hepatic veins, leading to portal HTN, ascites, and hepatosplenomegaly.
Ceruloplasmin and Copper Elimination
- major copper carrying protein in the blood
* copper eventually ends up in bile and is excreted in poop
VIPoma
- pancreatic islet cell tumors that secrete VIP
- inc. VIP inc. intestinal Cl loss
- VIP also inhibits gastric acid secretion
- somatostatin inhibits secretion of VIP and is used to tx VIPoma
- watery diarrhea, hypokalemia, achlorydria
Pompeii Disease
Deficiency of a-1-4 glucosidase (acid Maltese)
Cardiomegaly, macroglossia, and muscular hypotonia with hepatomegaly.
MEN1
- primary hyperparathyroidism (hypercalcemia)
- pituitary tumors (prolactin, visual defects)
- pancreatic tumors (gastrinomas)
- associated with zollinger ellison due to gastrin
- protein is menin
- also called Werner syndrome
MEN2a
- medullary thyroid cancer (calcitonin) with amyloid
- pheochromocytoma
- parathyroid
- also called sipple syndome
- RET genes
MEN2b
- medullary thyroid cancer (calcitonin) w/ amyloid
- pheochromocytoma
- mucosal neuromas/marfinoid habitus/neurofibroma
- RET gene
Niemann-Pick
- sphingomyelinase deficiency causes accumulation of lipid sphingomyelin
- hepatospelenopmegaly
- neurologic regression
- cherry red macular spot in infancy
Tay-Sachs
- deficiency in B-hexosaminidase A
- leads to GM2 accumulation in neurons
- neurologic regression
- cherry red spot on macula
- NO hepatosplenomegaly
Gauchers
- glucocerebrocidase accumulation
- B-glucocerebrocidase deficiency
- hepatosplenomegaly, pancytopenia, skeletal problems
- tissue paper macrophages
Fabry Disease
- a-galactocidase A deficiency
- globotriaosylceramide (ceramide trihexoside) accumulation
- neuropathic pain and dermatologic pathology in childhood
Krabbe Disease
- galactocerebrocidase deficiency
- accumulation of galactocerebroside and psychosine
- infants have developmental delay and/or regression, hyptotonia, optic atrophy, and seizsures
Zollinger Ellison
- gastrin secreting tumor of the pancreas
- causes GI mucosal ulceration
- high acid
- big folds
Menetrier Disease
- hyperplasia of surface mucous cells in stomach
- parietal cells dec (dec. acid)
- enlarged rugal folds
- dec. acid production, inc. risk gastric cancer
HLA associated with Celiac?
HLA-DQ 2 or 8
Whipple Disease
- infectious dz involving any organ
- caucasian males who work on farms
- tropheryma whipplei
- lamina propria of gut is filled with macrophages stuffed with PAS positive, gram +, rod shaped bacilli
- malabsorption, weight loss, diarrhea
- tx with antibiotics