Flashcards - Renal
fetal hydronephrosis
failure to canalize uteropelvic junction
fetal renal embryology
pronephros (week 4) –> mesonephros (1st trimester) –> metanephros (5th week on)
mulitcystic dysplastic kidney
defect when ureteric bud (caudal) meets with metanephric mesenchyme to induce differentiation, usually unilateral cystic kidney
Fanconi syndrome
PCT defect - loss of AA, glu, HCO3, PO4 = metabolic acidosis
Bartter syndrome
thick ascending loop defect - Na/K/2Cl (lasix)
Gitelman syndrome
DCT - NaCl reabsorption defect (thiazide)
Liddle syndrome
collecting tubule - increased epithelial Na channel activity (increased Na absorption)
Genetic causes of Horseshoe kidney
Edwards, Down, Patau, Turner
Hartnup disease
AR - neutral AA transporter defect (tryptophan –> decreased niacin, pellagra)
RTA Type I
DCT - inability to excrete H+ - urine pH >5.5 - hypokalemia
RTA Type II
PCT - unable to reabsorb HCO3 - urine pH <5.5 - hypokalemia
RTA Type IV
no aldosterone - adrenal/collecting tubule - hyperK –> decreased NH4 excretion - urine pH
heparan sulfate
provides negative charge barrier in basement membrane - lost in nephrotic syndrome
Loop diuretic
TALH - blocks Na/K/2Cl ATPase - can cause hypokalemia, gout, ototoxocity
Thiazide
DCT - blocks Na/Cl co transporter - can cause hyperGLUC, hypoK
Angiotensin II - tubule effect
PCT - stimulates Na+/H+ exchanger (increased Na+ absorption)
ANP/BNP
relaxes smooth muscle via cGMP –> increased GFR, decreased renin
Macula densa
senses decreased NaCl delivery to DCT –> adenosine release –> vasocontriction
Digitalis
blocks Na+/K+ - hyperkalemia
RBC casts
Glomerulonephritis, malignant hypertension.
WBC casts
Tubulointerstitial inflammation, acute pyelonephritis, transplant rejection. Nephrotic syndrome.
Fatty casts (“oval fat bodies”)
Acute tubular necrosis.
Granular (“muddy brown”) casts
End-stage renal disease/chronic renal failure and ATN
Waxy casts Hyaline casts
Nonspecific, can be a normal finding, often seen in concentrated urine samples.
IF: starry-sky, lumpy bumpy (IgM, IgG, C3 deposition in GBM and mesangium) EM: subepithelial immune complex humps
acute post-strep glumerulonephritis - group A b-hemolytic strep (pyo) - decreased complement levels, type III hypersensitivity