4/24 - UWorld Flashcards
Mechanism of action and major side effects of each drug in RIPE therapy
Rifampin - inhibits bacterial DNA-dependent RNA; causes red-orange body fluids
Isoniazid - inhibits mycolic acid synthesis; causes hepatotoxicity and neurotoxicity (give vitamin B6)
Pyrazinamide - unknown MOA; causes hepatotoxicity and hyperuricemia
Ethambutol - inhibits arabinosyl transferase (carbohydrate synthesis in cell wall); causes optic neuropathy (color blindness, central scotoma, decreased visual acuity)
Describe how PAH relates to GFR
PAH is freely filtered and secreted but not reabsorbed
Will slightly overestimate GFR
Describe how inulin relates to GFR
Inulin is filtered but not secreted or reabsorbed
Can be used to estimate GFR
Describe how creatinine relates to GFR
Creatinine is filtered and slightly secreted (but not secreted as much as PAH
Describe how urea is handled in the kidney
It is freely filtered and poorly reaborbed
But not as much net excretion as PAH and inulin
Describe how bicarbonate is handled in the kidney
It is actively reaborbed in the proximal tubule
What substances have almost 100% reabsorption in the proximal tubule?
Glucose and amino acids
What is a Barr body
Inactivated X chromosome
One of two X chromosomes in females is inactivated by being condensed into heterochromatin with heavily methylated DNA and deacetylated histones
What test is often used instead of bacitracin?
Pyrrolidonyl arylamidase (PYR) test
Strep Pyogenes is PYR-positive aka Bacitracin sensitive
What are the effects of a VIPoma?
WDHA
Watery diarrhea, hypokalemia, achlorhydria
What is Wilson disease?
Autosomal recessive defect in ATP-mediated hepatocyte copper transport
Results in lack of copper transport into bila and lack of copper incorporation into ceruloplasmisn (copper transport protein)
Copper accumulates especially in liver, brain, cornea, and kidneys
Presentation: liver disease, neurologic disease, Kayser-Fleisher rings (deposits in cornea)
Treatment: Penicillamine (chelates copper)
Describe the process of atrial sepation
What is Hartnup disease (defect, presentation, treatment)
Autosomal recessive deficiency of neutral amino acid transporters
Leads to decreased absorption of tryptophan, which is the source of niacin (B3)
Can lead to pellagra-like symptoms
Treat with high-protein diet and nicotinic acid
What type of HSR is atopic dermatitis?
Type I HSR
What type of HSR is contact dermatitis?
Type IV HSR
Describe the common presentation of L-sided vs. R-sided colon cancer
R-sided are more likely to bleed, leading to iron deficiency anemia
L-sided often infiltrate the colon wall, narrowing the lumen and leading to obstruction (altered bowel habits, constipation, abd distension, nausea, vomiting)
What terms from the 2x2 table can be used to help calculate ARR
ARR = NPV - PPV
Common presentation of Giant cell arteritis
Unilateral headache, jaw claudication, polymyalgia rheumatic (joint and muscle pain), blindness
Presentation of Takayasy arteritis
Usually Asian females < 40 y/o
Involves aortic arch at branch points
“Pulseless disease”, visual and neuro symptoms
What is depersonalization/derealization disorder?
Peristent of recurrent experiences of 1 or both:
- Feelings of detachment of being an outside observer of one’s self
- Experiencing surroundings as unreal
What is dissociative amnesia
Inability to recall personal information
Usually subsequent to severe trauma or stress
What is dissociative identity disorder
Aka multiple personality disorder
Sequence of events under light microscopy in acute MI
Time after myocardial infarction - Predominant light microscopic changes
0-4 hrs - minimal change
4-12 hrs - early coagulation necrosis, edema, hemorrhage, wavy fibers
12-24 hrs - coagulation necrosis and marginal contraction band necrosis
1 to 5 days - coagulation necrosis and neutrophilic infiltrate
5 to 10 days - macrophage phagocytosis of dead cells
10 to 14 days - granulation tissue and neovascularization
2 weeks to 2 months - collagen deposition / scar formation
Describe Wernicke vs. Korsakoff syndrome
Both cause by Thiamine (B1) deficiency
Wernicke encephalopathy is the acute effects - ataxia, confusion, ophthalmoplegia; atrophy of mamillary bodies
Korsakoff syndrome is the chronic effects - memory loss, confabulation, personality change
