Flashcards in Nephrology Deck (765)
what is a normal 24-hour urine protein?
less than 150 mg
how much protein w/i 24 hours indicates significant GLOMERULAR pathology?
more than 2 g/day (or 40-50 mg/kg/d)
how much protein w/i 24 hours indicates significant INTERSTITIAL pathology?
less than 1 g/day
the only exceptions in which there can be pathology and a NORMAL URINE SEDIMENT with MINIMAL proteinuria (2)
1. medullary cystic disease
2. obstructive uropathy
will urinary light chains in myeloma be picked up on a urine dipstick?
causes of false-positive urine albumin on urine dipstick: (6)
1. very alkaline urine with a pH > 8
3. heart failure (HF)
4. urinary tract infection (UTI)
6. very concentrated urine
common in people during a febrile illness, after strenuous exercise, and in pts w/ HF and COPD
first step in a pt w/ transient proteinuria
recheck UA (if negative; benign)
proteinuria reverts to near-normal when pt is SUPINE
BENIGN ORTHOSTATIC PROTEINURIA
what equates to 24-hour urinary protein?
spot protein:creatinine ratio
proteinuria ranges using spot ratio:
- overt proteinuria, usually d/t interstitial disease
- nephrotic range
- less than 0.15 (150 mg)
- 0.03 - 0.3 (30 - 300 mg)
- 0.3 - 1 (300 mg - 1 g)
- 3 - 3.5 (3 - 3.5 g)
EARLIEST indicator of diabetic and hypertensive nephropathy
indicate probable glomerulonephritis/nephritic syndrome
RBC casts, or "dysmorphic" RBCs
FEW RBCs on microscopic analysis, BUT urine dipstick is POSITIVE for blood
HEMOglobinuria or MYOglobinuria (rhabdomyolysis)
hematuria associated w/ proteinuria, especially if dysmorphic cells and/or RBC casts are present in the urine, is ALWAYS d/t
MCC of ISOLATED GLOMERULAR HEMATURIA (normal renal function, NO proteinuria)
- IgA nephropathy
- thin basement membrane disease
- early Alport syndrome
can cause transient hematuria
pts w/ sickle cell TRAIT may also have
isolated microscopic or gross hematuria is more likely what in origin?
in older pts, complete GU imaging must be done to exclude what?
renal cell or GU tract carcinomas
what GU imaging must be done to r/o renal cell or GU tract carcinomas?
US, MRI, or CT
w/ EOSINOPHILURIA, think of
drug-induced interstitial nephritis
w/ COARSE GRANULAR casts, or "MUDDY BROWN" casts, think
acute tubular injury
w/ OVAL FAT BODIES ("maltese crosses" under polarized light) may be seen in
what suggests rhabdomyolysis-induced renal failure?
unusually rapid rise in serum creatinine (more than 1.5 mg/dL over 24H)
in the elderly, what will be normal despite reduced renal function?
serum creatinine (sCr) is artificially INCREASED by these medications (4)
interfere w/ the test for creatinine and may falsely elevate results
indicates either PRERENAL AZOTEMIA (low flow and increased absorption), or increased protein breakdown
elevated (> 20:1) BUN:Cr ratio