test 6 Flashcards
postpartum psychosis
rare (0.1-0.2%) that lasts 4-6 wks post partum. suually manifests within the first 2 wks after birth. pt may have delusions, confusion, sleep disturbances, unusual behavior, emotional lability. tx: antipsychotics, antidepressants, inpatient hospitalization
achondroplasia: what is the problem?
activating mutation of FGF receptor 3 (and this constant activation actually inhibits chondrocyte proliferation). normal spine length but short limbs, large head, and saddle nose. is a sporatic mutation in 85% of cases; otherwise, it is autosomal dominant.
What drugs decrease warfarin activity?
anything that activates p450 system: rifampicin, phenobarbital and phenytoin.
also, cholestyramine binds warfarin adn many drugs and decr. the therapeutic effect of warfarin
syphilitic heart disease
tertiary syphilis (positive FTA-ABS) disrupts the vasa vasorum of the aorta with consequent atrophy of the vessel wall and dilation of the aorta and valve ring. may see calficifations of the aortic root and ascending aortic arch. leads to tree bark appearance of the aorta. can result in aneurysm and aortic insufficiency.
constrictive pericarditis
presentation: slowly progressive dyspnea, chronic edema, and ascites. rapid y descent that becomes deeper and steeper during inspiration is observed on JPV.
causes: TB, cardiac surgery, radiation therapy
diffuse esophageal spasm
periodic, non-peristaltic contractions of the esophagus. food bolus not propelled toward stomach. contractions may be painful. corkscrew esophagus on barium esophogram (q 13).
usually not associated with exertion and not relieved with rest, but always do a cardiac work up to be sure
femoral neck fractue
common in elderly pts w/ osteoporosis and a fall. femoral head and neck derive their blood supply from superior and inferior gluteal arteries and the medial and lateral femoral circumflex arteries (together, these vessels make the trochanteric anastamosis. medial femoral circumflex is vulnerable to damage from femoral neck fractures. injury or thrombosis of the medial femoral circumflex predisposes to avascular necrosis of the femoral head.
describe collagen synthesis and structure
- translation of collagen alpha chains (gly-X-Y; X and Y are usually pro or lys). glycine content reflects collagen synthesis. RER.
- hydoxylation of pro and lys resuides. this process requires vitamin C. RER.
- glycosylation: glycosylation of pro-alpha chain hydroxylysineand formation of procollagen via hydrogen and disulfide bonds. problems forming a triple helix –> osteogenesis imperfecta. RER.
- Exocytosis
- proteolytic processing: cleavage of disulfide rich regions of pro-collagen –> insoluable tropocollagen
- cross-linking: reinforcement of many staggered tropocollagen molecs by lysine-hydroxylysine cross linkage. performed by the Copper containing lysyl oxidase enzyme. problems with cross-linking is Ehlers danlos
elastin diseases
elastin is a stretchy protein that is found in lungs, large arteries, elastic ligaments, vocal cords, etc. rich in proline and glycine. nonhydroxylated forms.
marfan is caused by a defect in fibrillin, a glycoprotein that forms a sheath around elastin.
emphysema may be caused by an alpha1 antitrypsin deficiency that results in excess elastase activity.
Compare alcohol, chlorhexidine, hydrogen peroxide, and iodine as disinfectants.
alcohol: disrupts bacterial cell walls and denatures proteins. does not kill spores
chlorhexidine: disrupts cell walls and coagulates cytoplasm. does not kill spores.
hydrogen peroxide: produces destructive free radicals that oxidize cellular compartments. kills spores.
iodine: halogenation of proteins and nucleic acids. kills spores
myotonic dystrophy
prompt: weakness, gait disturbance, difficulty releasing doorknob. cataracts, frontal baldness, and gonadal atrophy. muscle atrophy involving type 1 fibers.
autosomal dominant trait d/t a trinucleotide repeat expansion of the gene tat codes for myotonia protein-kinase (DMPK).
lithium toxicity
neuromuscular excitability, coarse tremors, fascicular twitching, agitation, ataxia, heart block, hypothyroid, diabetes insipidus, and delirium.
Li is excreted by the kidneys, much like Na. renal injury, toxins, and drugs that change the GFR or electrolyte exchage in kidney can lead to increased proximal tubular absorption of sodium and lithium. vol depletion from GI losses, decompensated CHF, and cirrhosis can also cause increased proximal tubular reabsorption of sodium and lithium.
examples of drugs that can precipitate Li toxicity: thiazide diuretics, ACE-Is, and NSAIDs.
distinguishing btw different types of malaria
p vivax/ovale: fever every 48 hrs; add primaquine for hypnozoite (test for G6PD deficiency first).
P. falciparum: irregular fever pattern, severe. parasitized RBCS occlude capillaries in the BRAIN, KIDNEY, and LUNGs. if life-threatening, add quinidine.
P. malariae: 72 hr cycle. no dormant stage.
first line: chloroquine (blocks heme polymerase)
IgA deficiency
mostly asymptomatic, but can see airway and GI infections (esp. giardia lamblia), autoimmune disease, atopy, and anaphylaxis to IgA containing products (including blood).
amphotericin side effects
- acute infusion related rxns like fever, chills, rigors, and hypotension. premedication with antipyretics and antihistamines helps.
- dose-dependent nephrotoxicity b/c it decreases the GFR. don’t coadminister with other nephrotoxic drugs.
- electrolyte abnormalities (hypomagnesemia and hypokalemia.
- anemia (suppresion of renal EPO. may be severe in pts on zidovudine)
