renal casts + stones + cysts + tumors + failure Flashcards
cylindrical structure that forms in distal convoluted tubule + collecting duct
renal cast (cellular + acellular casts)
RBC casts
glomerular damage: glomerulonephritis
ischemia/infarction of kidney
malignant HTN: end-organ kidney damage
WBC casts
acute pyelonephritis
bacterial casts
pyelonephritis
epithelial cell casts
acute tubular necrosis
toxic ingestion: mercury, DEG, salicylates
waxy casts
chronic renal failure
low urine flow
hyaline casts
most common type substance secreted from tubular epithelial cells concentrated urine (dehydrated person)
fatty casts “oval fat bodies”
nephrotic syndrome
granular casts “muddy brown”
chronic renal disease
yellow, brown in color
cylindrical
RBC cast = pathology in kidney (vs RBCs = pathology anywhere in urinary tract)
pyuria
no casts
acute cystitis
hematuria
no casts
bladder cancer
kidney stones
complications of obstruction of stone in ureter/ureterovesicular junction → black flow of urine into glomerulus
hydronephrosis: expansion of pelvis of kidney
pyelonephritis
chronic renal failure, if untreated
most common type of renal stone
calcium stone
radiopaque (see on xray)
calcium oxalate +/- calcium phosphate
associated with hypercalciuria
calcium stone
causes of hypercalciuria
hypercalcemia: cancer, ↑ PTH
causes of calcium oxolate stones
ethylene glycol (antifreenze) ingestion vitamin C abuse (>2000 mg/day for long period)
prevent calcium stones
hydrochlorothiazide: decreases Ca in urine (loops loose, thiazides retain Ca)
urease + bugs (proteus mirabilis, staph, klebsiella, pseudomonas): urea →ammonia + H20
ammonia → ammonium binds to Mg, phosphate →”staghorn calculi”
ammonium magnesium phosphate stones (struvite stones)
staghorn calculi: outlines renal pelvis
ammonium magnesium phosphate stones (struvite stones) or
cystine stones
treatment of ammonium magnesium phosphate stones (struvite stones)
surgical removal of stone
only stone that is radiolUcent (use US or CT)
associated with hyperuricemia and gout
Uric acid stones
children with cystinuria
“staghorn calculi”
cystine stones
treatment of cystine stones
alkalinize urine
multiple BILATERAL cysts of ENLARGED kidneys
associated with LIVER cysts
ADPKD
flank pain hematuria urinary infections HTN progressive renal failure
ADPKD
in utero/infants fetal US: BILATERAL ENLARGED, echogenic kidneys absent or small bladder oligohydramnios → potter sequence
ARPKD
inherited
SMALL shrunken kidneys
fibrosis + progressive renal insufficiency
medullary cystic disease
common
usually outer cortex: inconsequential
simple cysts
multiple or thick/septated walls
follow or remove due to ↑ risk renal cell carcinoma
associated with dialysis
complex cyst
most common primary renal malignancy
renal cell carcinoma
cancer originates in renal tubular cells
polyglonal clear cells full of lipids + carbs
renal cell carcinoma
men 50-70 yo
hematuria
palpable flank mass
associated with paraneoplastic syndromes:
ectopic EPO → polycythemia
ectopic ACTH → cushing syndrome
ectopic PTHrP → hypercalcemia
↑ prolactin → hypogonadism, ↓ libido, galactorrhea
if invades IVC → spread in blood → mets to lung + bone
risk factor: smoking, obesity
renal cell carcinoma
associated with von Hippel Lindau syndrome
wilms tumor
most common renal malignancy of childhood (2-4 yo)
contain embryological glomerular structures
wilms tumor
child: 2-4 yo
huge palpable flank mass
hematuria
wilms tumor
associated with deletion of tumor suppressor gene WT1 on chrom 11
WAGR complex associated with gene mutation:
Wilms tumor
Aniridia (lack of iris)
GU malformations
Retardation (mental/motor)
wilms tumor
most common tumor of urinary system: renal calcyes, renal pelvis, ureters, bladder (transitional cells here)
transitional cell carcinoma
PAINLESS hematuria
risk factors: smoking (biggest), cyclophosphamide (can cause hemorrhagic cystitis and also induce TCC), aniline dye exposure
transitional cell carcinoma
WBC or WBC casts in urine fever nausea painful urination CVA AMS: elderly tx: empiric abx
acute pyelonephritis
eosinophilc casts → dilate tubules (thyroidization of kidneys)
chronic pyelonephritis
causes acute renal failure presentation: fever, rash, eosinophilia, azotemia common causes: *NSAIDs* penicillin cephalosporin, sulfonamides (TMP-SMX, furosemide) ciprofloxacin cimetidine allopurinol proton-pump inhibitors indinavir mesalamine
drug-induced interstitial nephritis (acute interstitial nephritis)
treatment of acute interstitial nephritis (drug-induced)
2 wks of CS
stop offending drug
common cause of acute renal failure in hospitals
cause:
muscle breakdown from seizures, crush injuries, cocaine use or statin drug use → rhabdomyolysis, myoglobinuria (myoglobin into kidney)
ischemia
radiocontrast dye (prevent with fluids + naHCO3)
nephrotoxic drugs: aminoglycosides
cephalosporins
polymyxins
acute tubular necrosis
sloughing of papillae gross hematuria flank pain proteinuria ischemic causes: sickle cell disease analgesia use: acetaminophen, nsaids diabetes pyelonephritis
renal papillary necrosis
types of acute renal failure
prerenal
intrsinisc
postrenal
insufficient blood flow to kidneys: hypovolemia hypotension shock renal vasoconstriction via NSAIDs kidneys try to compensate for low blood flow: BUN/Cr ratio >20
prerenal acute renal failure
intrinsic renal diseases that can lead to: acute interstitial nephritis acute pyelonephritis glomerulonephritis acute tubular necrosis DIC
intrinsic acute renal failure
obstruction of urine: stones BPH- blocks urethra neoplasia congenital anomalies
postrenal acute renal failure
BUN/Cr ratio >20
prerenal azotemia: prerenal acute renal failure
complications of renal failure
fluid retention (can't produce urine): peripheral edema, HTN, heart failure, pulmonary edema hyperkalemia (retain K+) metabolic acidosis (high H+) anemia (low epo) low Ca uremia:high BUN, Cr
symptoms of uremia
manifestations of severe azotemia: ↑BUN/Cr nausea anorexia pericarditis asterixis encephalopathy platelet dysfunction
acute generalized cortical infarction of both kidneys
due to vasospasm + DIC
associated with multi-organ failure, ARDS, DIC (all can be caused by septic shock)
diffuse cortical necrosis
no vitamin D activation → less Ca reabsorption in gut → 2° hyperparathyroidism → degrade bones to ↑ Ca
tx: vitamin D + Ca in renal failure patients
renal osteodystrophy
differential diagnosis for blood/red urine
rifampin
excessive ingestion of beets
UTI, kidney stones, bladder cancer
