Flashcards in Renal Deck (68):
Where is the macula densa? JG cells?
Macula densa are cells w/in DCT
JG cells are modified SmM of aff art, make connection w/ DCT and macula densa
Body water is where?
60-40-20 (% of body wt)
60% TBW, 40% ICF, 20% ECF (1/4 pl vol, 3/4 interstitial vol)
vol of pl from which the substance is cleared per unit time:
C [ml/min] = [U] x V / [P]
- Cr over or underest's GFR?
GFR = CL(inulin) = UV/P, where U is the urine conc of inulin, P is the pl conc of inulin, and V is the urine flow rate
- slightly overest's bc is secreted
Is ERPF really RPF?
use PAH for est'd renal pl flow bc all PAH that enters kidneys is excreted:
ERPF = UV/P = CL of PAH
- RBF = RPF / (1-Hct)
- no, ERPF underest's true RPF by about 10%
Filtered load =
FF = GFR/RPF, nl is 20%
Filtered load = GFR x pl conc
What effect do PGEs and ATII have on FF?
PGEs don't affect FF bc they incr RPF -> incr'd GFR
ATII incr's FF bc decr RPF -> incr'd GFR
What effect do NSAIDs and ACEIs have on FF?
NSAIDs constric aff art (prevent dilation) -> decr'd RPF and GFR -> no change in FF
ACEIs dilate eff art (prevent constriction) -> incr'd RPF and decr'd GFR -> decr'd FF
Filtered load =
Excretion rate =
How to calc reab'n? secretion?
GFR x [P]x
V x [U]x
Reab'n = filtered - excreted
Secretion = excreted - filtered
Pl glc reab'n threshold?
Glc reab'n sat'n max at?
- What happens in nl preg?
~160 -> glucosuria
350 -> all transporters fully sat'd (Tm)
- Reduced reab'n of glc -> glucosuria and aminoaciduria (also not ab'd as well)
Hartnup's dz =
defic in neutral AA (Tryptophan) transporter -> pellegra
ATII's affect on kidneys?
PTHs 2 affects on kidneys?
- PT: stim's Na/H exchange -> reab'n of Na, water, bicarb -> contrac alkalosis
- PT: inhib's Na/phos cotrans -> phos excretion; and DCT: stim's Ca/Na exchange -> incr'd Ca reab'n
What 3 things stim renin release from kidney?
Decr'd BP (sensed by JG cells)
Decr'd Na deliv (sensed by MD cells)
Incr'd symp tone (on b1 Rs)
Why don't you get reflex brady w/ incr'd BP from ATII?
ATII also affects baroR func -> limits reflex brady
ADH reg's osmol's (except w/ low bl vol then incr's water reab'n to save vol)
Aldos reg's bl vol
EPO is made by?
Act'd VitD is made where?
- Interstitial cells in the peritubular capillaries
- In the PT cells by 1a-hydroxylase
3 things that stim PTH release?
Decr'd pl Ca
Incr'd pl PO4(3-)
Decr'd pl 1,25-(OH)2 VitD
Insulin defic -> what effect on K?
Thus incr'd insulin does what?
Causes hyperK bc decr'd act'n of Na/K pump
- Incr'd INsulin shifts K INto cells (hyopK)
HyperK shows what on EKG?
- wide QRS and peaked T waves, arrhythmias
- tetany, seizures
- tetany, arrhythmias
Winter's formula =
- use for?
PCO2 = 1.5(bicarb) + 8 +/-2
to determine what PCO2 should be w/ simple metab acidosis (determine if resp compensation is adequate of it there is a mixed acid-base d/o)
- check when?
AG = Na - Cl - HCO3-
check w/ metab acidosis to see if it's gap or non-gap acidosis
Causes of gap metabolic acidosis?
Methanol (formic acid)
Iron tab's or INH
Ethylene glycol (oxalic acid)
Causes of non-gap metab acidosis?
Addison's dz (decr'd aldos)
Salicylate poisoning causes what change in bl pH first? then later?
Early: rep alkalosis bc stim's resp center -> hypervent
Late: metab acidosis bc of acid
4 causes of metab alkalosis?
loop diuretics (incr'd Na to DCT, and incr'd H+ out)
antacid use (less H+)
hyperaldos (incr'd H+ out)
Type I RTA has incr'd risk of?
Ca phosphate kidney stones bc of alk urine pH and bone resorption
Type II RTA has incr'd risk of?
- May see this RTA w/?
- Fanconi's synd
Nephrotic synd sx?
6 nephrotic synd's are?
proteinuria >3.5g/d, frothy urine from incr'd albinuria, hyperlipidemia, fatty casts, edema, incr'd coag state (decr'd ATIII), incr'd risk of infec (loss of Igs)
- Membranous nephropathy, MPGN (also a GN synd), MCD -> FSGS, Amyloidosis, Diabetic nephropathy
Fat Hispanic/AfAm w/ HIV, does heroin, on IFN trtmt and has effacement of foot processes -> what renal synd?
Spike and dome appearance on EM, has SLE and a tumor, and is a Caucasian adult -> what renal synd?
Kid w/ recent cold -> what renal synd?
MCD (aka lipoid nephrosis) can progress to FSGS), cytokines from infec (or R-S cells in HL), KO podocytes)
Chronic conditions like MM, TB, RA -> what renal synd?
C3 nephritic factor -> what renal synd?
Type II MPGN (intramem IC deposits)
- is autoAb that stabilized C3 convertase -> incr'd act'n of C': C3->C3a+C5a -> decr's C3 in circ
HBV/HCV -> what renal synd?
Type I MPGN (subendo IC deposits)
Mesangial expansion w/ pink nodular glomerulosclerosis -> what renal synd?
Diabetic nephropathy w/ Kimmelstiel-Wilson lesions
Nephritic synd has what sx?
- 5 ex's of it?
Inflamm process -> hematuria, RBC casts in urine, azotemia, oliguria, HTN and proteinuria <3.5g/d
- Acute post-strep GN, RPGN (crescents), DPGN, IgA nephropathy, Alport synd
Lumpy-bumpy appearance on LM in person w/ recent cold -> what renal synd?
Acute post-streptococcal GN (from Strep w/ M pr VF), w/ subepi IC deposition (granular on EM)
Crescents in ? renal dz, are made of?
Crescents are made of fibrin and Mphage (inflamm debris)
c-ANCA renal dz?
p-ANCA renal dz?
Granulomatosis w/ polyangiitis (Wegener's)
Microscopic polyangiitis (also Churg-Strauss)
Granular IF and SLE -> what renal synd?
DPGN, subendo and sometimes intramem IgG ICs often w/ C3 deposition
Mesangial IC deposits -> what renal synd?
- presents why?
IgA nephropathy (Berger's dz)
- mucosal infec -> incr'd IgA made
Deaf, renal problems and eye problems = what synd?
Ca (oxalate/phosphate) stones:
- see on XR?
Thiazides and citrate
Staghorn calculi is made of?
- due to infec w/ what?
Ammonium magnesium phosphate stone
- Urease (+) bac: Proteus, Staph, Klebsiella
What is the only kidney stone that you can't see on XR?
Uric acid stone, from gout or conditions w/ high cell turnover (leukemia)
- KHCO3 to alkalize urine and hydration
Staghorn hexagonal stone in a kid is what?
Cystine stone, assoc'd w/ Cystinuria (genetic decr'd reab'n of Cys)
RCC is assoc'd w/ what gene deletion?
- assoc'd w/ what paraneoplastic synd's?
VHL gene on chr3
- EPO, ACTH, PTHrP, renin
VHL dz =
RCC + hemangioblastoma of Ce
Wilm's tumor is made up of cells from?
Embryonic glom struc's (blasthema cells)
WAGR complex =
Beckwith-Wiedmann synd =
Painless hematuria w/ no casts ->
Bladder ca (transitional cell ca)
- often multifocal and will recur due to field damage of entire bladder epithelium
What is assoc'd w/ problems in your Pee SAC (aka bladder)?
Aniline dyes (hair dyes)
White cell casts in urine =
- 3 causes?
Pylonephritis (E.coli, Klebsiella, Enterococcus)
Tubules w/ Eo'ic casts (aka thyroidization of kidney) is caused by?
Chronic pyelonephritis (coarse asymm corticomedullary scarring, blunted calyx)
4 causes of drug-induced AIN (acute interstitial nephritis)?
Diuretics, Pn's, sulfonamides, rifampin
- 1-2wks after drug use, or mo's after starting NSAIDs
Granular muddy brown casts =
ATN (renal ischemia from shock/sepsis, crush injury w/ myoglobinuria, drugs, toxins (usu PT)
Can get renal papillary necrosis from recent infec or imm stimulus, inc'ing (4)?
DM, acute pyelo, chronic phenacetin (acetaminophen) use, SCA/trait
Prerenal azotemia bc kidneys are working fine to conc urine and reab Na
FeNa is >two w/ urine osmol <15
Intrinsic renal azotemia bc kidneys aren't working to conc urine nor to reab Na nor to reab BUN
FeNa >two w/ urine osmols 15
Postrenalazotemia bc kidneys have back P on them so can't conc urine nor reab Na very well, but can reab BUN bc back P pushes BUN into bl
In renal failure:
HyperK (can't excrete K+)
Metab acidosis (can't excrete org acids)
No, bc plt dysfunc from uremia
Off, esp have high TGs
Low Ca causing renal osteodystrophy is from what 2 causes?
1) low VitD (can't be act'd in kidneys) -> low Ca reab'n from gut
2) high phos binds Ca, decr'ing free Ca
3 things assoc'd w/ ADPKD?
What is assoc'd w/ ARPKD?
- hepatic cysts -> congenital hep fibrosis causing portal HTN
Cysts in renal cortex + small kidneys =
Medullary cystic disease
Which diuretics cause acidemia? which cause alkalemia?
Acidemia: CA inhib's, K+ sparing aldos blockers
Alkalemia: Thiazides and loop diuretics (incr K loss -> incr'd exchange for H+)
Which diuretic causing hypocalcemia?
Which causes hypercalcemia?
Thiazides (can cause Ca renal stones)