renal Flashcards
parts of developing kidny
pronephors, degen at 4 weeksmesonephros (interim kdiney)
metanephros (permanent)
when does metanephros appear
5th week
how does glomerulus through to DCT form
utereric bud interacts with metanephric mesenchyme which induces differentaiton
last part of uro system to canalize
ureteropelvic junction MOST COMMON SITE OBSTRUCTION
potter sequence etiology
anything that causes OLIGOhydramnios
ARPKD, obstructive uropathy (posterior urethral valves), bilateral renal agensis
cause of death in potter sequence
pulmonary hypoplasia
symptoms of potter sequence
all compression related POTTER Pulmonary hypoplasia oligohydramnios twisted face twisted skin extremity deformities renal failure in urtero
etiology horsehoe kidney
abnormal fusion of inferior poles of both kidneys
what does the horshoe kidney get stuck under as it ascends from pelvis during dvlpmt
IMA
thats why they remain low in abdomen
complications of horshoe kidney
kidney function NORMAL but
can develop hyronephrosis (uteropelvic junction), renal stones, infection,
unilateral renal ageneiss vs multicystic dysplastic kidney
unilateral - complete absence of kidney and ureter
multicystic - nonfunctional kidney is just a bunch of cysts and connective tissue
BOTH INVOLVE FAILURE OF URETERIC BUD TO INDUCE DIFFERENTIATION WITH METANEPHRIC MESENCHYME
y shaped bifid ureter
duplex collecting system
assocaitd with vesicoureteral reflux or ureteral obsrution
MCC cause of bladder outlet obstruction in male infants
posterior urethral valvues
presents with hydronephrosis
ureters travel under what structures
female - uterine artery
male - vas deferens
water under bridge
renal blood flow from renal artery to venous outflow
renal artery segmental artery interlobar artery arcuate artery interlobular artery afferent arteriole glomerulus efferent arteriole vasa recta/peritubular capillaries venous outflow
GFR barrier composed of….
fenestrated capillary endothelium
basement membrane with type IV collagen
epithelial layer of PODOCYTES
which is a better filter fenestrated capillary epithelium or podycyte foot processes
podocyte foot processes forms slit diaphragm chich presvents 50-60 nm molecules
fenestrated capillary prevenst greater than 100
charge of GFR barier
negatively charge glycoproteins (prevent postiive charged molecule entry)
where does AT II target on nephron
PCT - stimulates Na/H exchange (inrease Na reabsorption, h20, and hc03 reabs) permitting contraction alkalosis
how does angiotensin II affect RBF
constricts efferent arteriole
ANP stimulated by what
increases in atrial pressure…will increasee GFR and NA filtration with no reabsorption…Na loss and water loss (brake on RAAAS system)`
how is EPO released
releasd by intertitial cells in peritubular cap bed in response to hypoxia
formula correlating RBF and RPF
RBF = RPF/1-Hct
every time GFR halves serum creatinine will
double (creatinine not a sensitive indicator of kidney function when GFR is normal)
which part of nephron is impermeabl to water despite adh
thick ascending loop
winters formula
predicted Pco2 =( hco3x1.5) + 8 +/-2
what part of nephron is Mg and Ca reabsorbed
Thick ascending loop
distal RTA type 1
distal tubule cannot acidify urine (urine ph high) assocaited with hypokalemia
low bicarb
assocaited symptoms of distal RTA type 1
alkalinized urine increases risk for calcium phosphae kidney stones
an rickets
how to calculate URINE anion gap
Na + K - Cl
what is the Cl in urine anion gap a good approx for?
Nh4 (Nh4 leaves with Cl)
Urine anion gap in setting of GI acidosis like diarrhea
UAG becomes negative (more chlorine leaving and NH4)
Urine anion gap in setting of distal RTA?
since urine can’t be acidified, it does not become negative despite acidosis
when given ammonia “challenge” (acid load of NH4Cl) what will RTA urine ph be
would still be greater than 5.3
negative UAG in acidosis vs psoitive UAG in acidosis
negative UAG = GI acidosis
postivie UAG - RTA
autoimmune disease (srogens or RA) presents with bilateral recurrent kidney stones, with high urine pH, hypokalemia, positive UAG
distal RTA
urine pH high or low ins type II proximal RTA
low as it should be
since DCT can still excrete H+
loss of HCO3 resportion in PCT
proximal rta type II
why is proximal rta type II assocaited with hypokalemia
low bi carb, low volume, increase in aldosterone, HYPOKALEMIA
assocaited with fanconi syndrome
type II proximal RTA
hypophosphatemic rickets BUT NO KIDNEY STONES
type II proximal RTA
only RTA with hyperkalemia
type 4 RTA
dysfuction of aldosterone channels
type 4 rta (distal)
dysfunction of distal H/K exchanger
type 1 RTA distal
dysfunction of proximal bicarb channels HCO3
type 2 rta
noninherited cysts in kidnys
dysplastic kidney
inherited defect, BILATERAL enlarged kidneys with cysts in renal cortex AND medulla
Polycystic kidney disease
infant PKD
autosomall recessive
renal failure HTN
ARPKD assocaited with what complications
cysts in kidney- so bad you can get oligohydram-> potter
cysts in LIVER also -> PORTAL HTN -> hepatic fibrosis
ADPKD presents what age
young adults
mutation ADPKD
APKD1 APKD2, cysts develop GRADUALLY over time
why do ADPKD present wiht HTN
can have dysfunctional release of renin
CNS complication of ADPKD
berry aneurysm
cardiac complication ADPKD
MVP
inherited defect ONLY IN MEDULLARY COLLECTING DUCTS
medullary cystic kidney disase (kidneys are SHRUNKEN)
shrunken kidneys
medullary cystic kidney disease
prerenal Bun:cr ratio and FeNa, urine osm
BunCr>15
FeNa < 1 (tubules still able to resorb Na)
urine osm > 500 (high)
key finding ATN
granular “muddy brown “ casts in urine
Bun cr, FeNa, Urin osm in intrinsic renal
Buncr low
Fe na High
urine osm low
part of nephron most suseptible to injury during renal failure
PCT and thick ascending limb
agents that can cause nephrotoxic injury
aminoglycosies heavy meatlas myoglobinuria (crush injiry) urate (TLS) radiocontrast!
how does ATN afect acidase status and potassium status
metabolic acidosis
hyperkalemia
how long can oliguria persist in ATN
2-3 weeks before recovery (tuublar cells are stable cells)
drug induced hypersensivitiy reaction of intersitium
acute interstitial nephritis
oligura, fever, RASH, hematuria with Eosinophils
aute interstitial neph
key finding in urine in AIN
eosinophils
drugs tha can induce AIN
P's Pee (diuretics) Pain free (NSAIDS) Penicillins PPi rifamPin