Download USMLE Step 2 CK - Nephrology and more Exams Nephrology in PDF only on Docsity!
USMLE Step 2 CK - Nephrology
best initial test in nephrology - ✔urinalysis plus bun and cre constituents of urinalysis - ✔protein and wbc or leuko esterase and rbc and spec gravity and ph and nitrites persistant non orthostatic proteinuria next step - ✔kidney bx to determine the amount of proteinuria - ✔protein to cre ratio. if ratio equals 1 pr.uria 1 g/d. if 2,5 then 2,5 g/d. (superior in accu to 24h urine, choose ratio if both are available) to determine the cause of p.uria - ✔bx dm plus microalb.uria next step - ✔give acei or arb. decr prog of disease and deve of rf bjuria detectable on dipstick? no. use i.phoresis - ✔ eosinuria value - ✔high spec low sens pers wbc on ua but neg culture - ✔may be tbc nsaid induced renal disease, eosinuria? - ✔no allergic interstitial nephritis urine finding - ✔eosin detected using wright and hansel stain normal rbcs in urine - ✔< fp hematuria, causes - ✔hburia or mgburia trauma and drak urine, dipstick pos for blood. best initial test to confirm dx - ✔micro exam of urine
cystoscopy, when? - ✔there is hematuria but no inf or trauma andrenal usg or ct show no etiology or bladder usg shows a mass to bx prerenal bun and cre - ✔rise in bun>cre these may also cause prerenal - ✔hypoalbu, cirrhosis, nsaids (constrict aff arteriole), acei (dilates eff arteriole), pancreatitis aki symps? - ✔may be asymp. n&v, tired, malaise, weak, short of breath, edema. if severe confusion (arrhythmia from hyperK and acidosis), pericarditis (sharp pleuritic pain) bun/cre ratio in pre, post or intrinsic renal diseases - ✔above 20:1 in pre and post, closer to 10:1 in intrinsic cause of aki is not clear, next best dxtic step - ✔urinalysis and UNa, FENa, urine osm. if all are in the choices go with urinalysis first prerenal, UNa and FENa - ✔UNa below 20, FENa below %1. both gives the same info. (decr bp incr aldos, aldos incr Na reabs) prerenal, Uosm - ✔incr (>. (decr iv volume incr adh. adh incr water reabs.) atn, Uosm - ✔inapp low. usually isosthenuria (300 mosm/l)(also called renal tubular conc defect). (damaged tubule cells cannot conc urine) atn, UNa - ✔above 20. canot reabs Na because cells are dead only mani of hbs trait - ✔isosthenuria. just avoid dehydr urine spec gravity correlates to - ✔Uosm (direct correlation) atn 36 h after hosp. admission and dxtic tests, possible cause - ✔radio contrast media. drugs usually cause a rise in cre 5-10 days after the adminstration
✔low dose d, diuretics (do not forget that furo plus ag causes ototox. related to total dose and injection rate), mannitol, steroids hepatorenal synd labs - ✔very low UNa (10-15), FENa below 1%, BUN/cre>20: hepatorenal synd rx - ✔midodrine, octreotide, albumin renal atheroemboli pres - ✔recent cath procedure, aki, blu/purplish skin lesions in fingers and toes, livedo ret, ocular lesions renal a.emboli labs - ✔eosinilia, eosinuria, low c levels, incr esr renal a.emboli most accu test - ✔bx of a purplish lesion. shows chol crystals. but no change in management ain, causes - ✔penicillins, cephalo, sulfas, rifampin, fqs, phenytoin, allopurinol, ppi (these also cause allergy, rash, sjs, ten, hemolysis), sle, sjogren, sarco ain pres - ✔fever, rash, arthralgia, eosinuria (not if nsiads) and ilia. bun/cre below 20, wbc and rbc in the urine ain most accu test - ✔Hansel or Wright stain (ua cannot distinguish eosins). no help from fena or spec gravity ain rx - ✔usually resolves sponta. if severe temp dialysis. if cre rises after stopping the drug give cs analge nephr presents with - ✔atn and ain and memb gn and renal vasc insuff (symp in older and rf patients) and papillary necrosis papillary necrosis history - ✔nsaid use PLUS hbs, dm, urinary obs, chr pyeloneph papillary necrosis pres - ✔sudden onset of flank pain, fever (in few h not few days in acute pyeloneph), hematuria (or grossly visible necrotic material)
papillary necrosis best initial test - ✔ua (rbc, wbc, necrotic material) papillary necrosis best most accu test - ✔ct (bumpy contour of where papillae are lost vs diffusely swollen kidny in acute pn) glomerular diseases most accu test - ✔bx (now always needed) gn UNa and FENa - ✔low goodpasture vs wegener - ✔no upper resp involv in goodpasture. only lung and kidney (also no gi, neuro, skin, joint) goodpasture best initial and most accu test - ✔antiglomerual bm ab and bx from lung or kidney (linear deposits). also chr blood loss from hemoptysis and abn cxr goodpasture rx - ✔ppheresis and steroids. cyc may help number 1 acute gn in us - ✔iga neph iga neph timescale with uri - ✔1-2 days after. asian patient iga neph most accu test - ✔bx iga neph indicator of severity and rate of prog - ✔proteinuria iga neph px - ✔30% totally resolve, 40-50% slowly prog to esrd iga neph rx - ✔if proteinuria is severe give cs and acei psgn timescale with inf - ✔1-3 wks after inf psgn bx? -
top causes of nephrotic synd - ✔ht and dm edema in chf vs nephrotic synd - ✔dependent area in eg in legs in chf. everywhere in nephrotic synd nephrotic synd best initial test - ✔ua albumin/cre ratio gives - ✔average protein produced over 24 h (eg if ratio is 2:1 then proteinuria is 2 g/d) periorbital edema is charactristic of - ✔nephrotic synd most accu test for determining the cause of neph synd - ✔renal bx nephotic synd best initial rx - ✔cs. if no resp over several weeks, immunosupps like cyc. acei to control proteinuria. salt rest and diuretics for edema. statins for hperlipidemia esrd definition - ✔need for dialyisis or tx. uremia top causes of esrd - ✔dm and ht uremia is defined as - ✔met acid and fluid overload and encephalopathy and hyperk and pericarditis (these are all indications for dialysis) peritoneal and hemo- dialysis effectiveness - ✔equal mani of rf and their rx - ✔anemia (fe supp and epo inj), hypoca (give vit d and ca), osteodystrophy, bleeding (ddavp when bleeding), inf.s, pruritus (dialysis and uv), hyperp (p binders), hypermg (rest high mg, laxatives and antacids), accelerated atheroscl(dialysis), ht, endocrinopathy (anovulation, low T, erectile dysfunc.) (dialysis, e and t replacement) oral p binders - ✔ca acetate, ca carbonate, sevelamer, lanthanum. use the latter two when ca is high. no aluminum p binders. al causes dementia
ttp is asc with - ✔hiv, cancer, cyclosp, ticlopidine, clapidogrel the only indispensible finding of ttp - ✔iv hemolysis hus rx - ✔if e. coli most sponta resolve. if severe needs urgent ppheresis. if no ppheresis give ffp. no cs. no plt ttp rx - ✔urgent ppheresis. if no ppheresis give ffp. no cs. no plt polycystic pres with - ✔pain, hematuria, stones, inf, ht pckd top cause of death - ✔rf pckd may also have - ✔liver cysts, ovarian cysts, mvp, diverticulosis hyperna may be caused by - ✔sweating, burns, fever, pneu, diarrhea, diuretics, di ndi, causes - ✔li, democlo, chr kidney disease, hypok, hyperca first clue to the pres of di - ✔high vol nocturia di best initial test - ✔water rest and measuring urine vol and osm ndi rx - ✔correct k and ca, stop li or demeclo. if no resp give HClthiazide or nsaids hypervol hypona, causes - ✔chf, nephrotic synd, cirrhosis (decr iv vol, incr adh levels) hypovol hypona, causes - ✔sweating, burns, fever, pneu, diarrhea, diuretics PLUS chronic water replacement (these cause hyperna), addison euvol hypona, causes - ✔pseudohypona (hypergly), psych polydipsia, hypothy, SIADH
hypok, k fails to rise despite adeq replaacement - ✔check mg levels. hypomg causes incr urinary k loss anion gap formula - ✔na-cl-hco3. n values are 6- most important causes of n ag met acid - ✔rta and diarrhea (hypercl acidosis) rta 1, causes - ✔ampB, sle, sjogren. rta 1, patophys - ✔no new hco3 is generated in distal tubule, no acid sec. high urine ph. causes stones (ca oxalate) rta 1, best initial test - ✔ua. ph above 5,5. rta 1 most accu test - ✔acid plus ammonium cl infusion. cannot exc acid and urine ph remains high rta 1 rx - ✔give hco rta 2, causes - ✔amyloidosis, myeloma, fanconi, acetazolamide, heavy metals rta 2, pathophys - ✔prox tubule cannot reabs hco3. but urine ph is low (hco3 is depleted eventually, first urine is basic). chr met acid causes osteomalacia rta 2, most accu test - ✔give hco3 and test urine ph. no hco3 abs causes high urine ph rta 2 rx - ✔thiazides (causes volume depl which will enh hco3 reabs) rta 4 #1 cause - ✔dm rta 4 pathophy - ✔decr effect of aldos at tubules. na and h retention rta 4 findings - ✔pers high urine na despite a na depl diet plus hyperk
cs with highest mineralocort effect - ✔fludro rta 4 rx - ✔fludro how to distinguish diarrhea vs rta - ✔urine ag. na-hco3 or na-cl. rta has pos uag. in rta acid secr is decr, so the buffer by nh4cl is decr, so urine cl is decr. in diarrhea acid exc is intact and to compensate met acid kidney secr acid. neg uag in diarrhea minute vent equals - ✔resp rate x tidal vol (more accu than resp rate) causes of resp alka - ✔anmeia, anxiety, pain, fever, inters lung disease, pulm emboli causes of resp acid - ✔copd, emphysema, opiate od, aat def, kyphoscoliosis, sleep apnea, morbid obesity most common kidney stone, urine ph, cause - ✔ca oxalate, alkaline urine, overexc of ca obviously a stone, next step - ✔nsaids cd causes which stones - ✔oxalate most accu test of kidney stones - ✔ct wo contrast stones that are not visible on xr but on ct - ✔uric acid best initial rx for acute renal colic - ✔analgesics, hydr, ct and USG (to detect obs) (if <5 mm pass sponta, if 5-7 give nifedipine and tamsulosin to help pass) etiology of stone is determined by - ✔stone analy, serum ca, na, urate, ph, mg, p, 24 h urine for vol, ca, oxalate, citrate, cystine, ph, urate, mg, p cystine stones rx -
✔acei or arb ht plus bph - ✔alpha blockers ht plus depression or asthma - ✔avoid BBs ht plus hyperthy - ✔BB first ht plus osteoporosis - ✔thiazides ht crisis defined by - ✔ht plus confusion or blurry vision or dyspnea or chest pain ht crisis best initial rx - ✔labetolol or nitroprusside (needs monitoring so usually not the first choice). may also use enalapril, diltiazem, verapamil, esmolol, hydralazine, fenoldopam (all iv). do not lower to normal, may cause stroke
