LABS Flashcards
Fatty casts are ass/w?
Nephrotic syndrome mostly
ARF cause if FE sodium is <1 percent
Decreased perfusion (Hypovolemia or dehydration)
Kidney is retaining water/NA to increase volume -
UA Na is low
Crystal types
Uric acid
Calcium phosphate/oxalate
Cystine - Hereditary cystinuria
Struvite - Infection stones - (urease- proteus/klebsiella)
Trace protein indicates quan of?
<150mg/D
Other reasons keytones would be positive?
Starvation/Fasting, Carb free diet, dehydration, preg, ETOH
Gold standard of GFR measurement is?
Inulin Carb - (MC and convenient is Creatinine clearance)
Increased SG indicates?
Dehydration/Shock
Decreased SG indicates?
Overhydration, Cant concentrate urine
RBC casts are hallmark of?
Glomerulonephritis
GF pH is?
7.4 (acidifies thru tubules)
MOst important measurement of renal FX?
GFR - (Kidney status and RX adjustments)
FE sodium concept is
Amount of NA remaining in urine after filtration
pH is good for assessing?
UTI, Stones, Renal tubular acidosis
Cockcroft & gault formula?
(140-age) x (Ideal body weight Kg) / Plasma Cr x 72
Multiple total by 0.85 for females
NL GFR range is?
90-120mL/min
NL bun range is?
5-20mg/dL
BUN is decreased w/?
**Liver DZ - (Cant metabolize ammonia to urea)
Renal HYPERperfusion (Preggo, SIADH)
Overhydrated
WBC casts w/ EOS are seen W/?
Acute interstitial nephritis
Broad casts indicate what?
Severe urinary stasis
Random UA pH NL range?
4.5-8.0
Waxy casts are ass/w?
Severe urine stasis in tubules - CKF
WBC Casts are ass/w?
Acute pyelonephritis vs Low UTI D/O
Protein is often an 1st indication of?
Renal disease
Micro- Types of epithelial cells
Squam - >10/HPF = contamination
Transitional - LRG/Clumping = neoplasm (req cytology)
R. Tubular - DX for ATN (ischemic or nephrotoxic)
F= of Blood Dipstick due to?
High Vit-C (ascorbic acid)
W/out using a 24hr creatine clearance collection what is another way to determine GFR?
- Cockcroft & Gault
2. Modification of diet in renal disease (MDRD)
Increased Scr is due to ?
Renal failure
Increased protein diet/muscle
Azotemia is?
Excess nitrogenous waste
Decreased Scr is due to?
Veg diet
Decreased muscle mass (OLD/PED)
Mechanisms of regulating GFR?
Controlling BF in/out by changing diameter of AFF/EFF
Control Glom surface area by contract/relax mesangial cells.
F= Leukocyte esterase can be due to?
Concentrated Urine
Glycosuria
RX - Tetracycline/Cephalexin
ARF cause if FE sodium is >1 percent (often >3)
Intrinsic renal disease
Kidney is losing NA inappropiately - Urine Na is high.
Another name for transitional epithelials?
Urothelial cells
Casts are formed how?
Formed in the DCT/CD w/ Tamm-Horsfall protein and suggest parenchymal DZ
Increased BUN:Creatinine ratio is due to?
Prerenal - Dehydration
Postrenal - Obstruct
F+ nitrite due to?
Contamination/gross hematuria
Waxy casts are essentially what?
End stage disinegration of a cast
Bilirubin dispstick detects?
Conjugated bili (unconjugates is insoluble)
Dipstick keytones detects what? Useful for?
Acetic acid - ketosis, DKA
If you suspect UTI or Pyelonephritis should order?
UA Cx (>100k pos - 1-10k can still be + however)
Fractional excretion of sodium is used when?
Suspecting acute renal failure (most accurate with oliguria)
RBC morphology characteristics
Round/NL - Dz along epithelial lining
Dysmorphic - Irreg shape = nephritic disease
Crenated - Concentrated urine
Ghost RBC - swollen (dilute urine)
Micro - WBC eval cutoff?
> 5 WBC/HPF = pyuria (urinary tract injury)
Most accurate creatinine clearance is by?
24h UA collection (impractical)
Urobiligen range? detects?
NL= 0.2-1.0mg/dL
Byproduct of Conjugated bili breakdown in GI by bacteria
Orange colored urine RX
Phenazopyridine
Nitrofuranotin
Rifampin
Metronidazole
1st AM UA pH NL range?
5.0-6.0
BUN Creatinine ratio NL ratio is?
10:1
Factors of GFR are?
Age, Size, Physiological status
Leukocyte esterase is from?
Seg enzymes (Neutrophils predominate)
Scr is used for?
Measuring GFR (creatinine clearance - muscle metabolism)
MDRD Ccr is useful for?
OLD/Obese and corrects for sex/black
Oligura is defined as
<400ml
Micro - RBC eval cutoff?
> 3 RBC/HPF
Regulation pathways of GFR?
- Renal autoregulation
- Neural regulation
- Hormonal regulation
Dipstick blood measures?
RBC, free Hgb, myoglobin
Urea is a?
End product of protein catabolism measured w/ BUN
Increased urobili suggests?
Hemolysis or Hepatocellular disease
Bun is inverse to what?
GFR
Normal SG range? Used for?
1.005-1.030 - Hydration status/Concentrating ability
Sterile pyuria labs?
Pos WBC - Neg Cx
R. tubular casts are ass/w?
ATN
BUN is increased w/?
Renal hypoperfusion (CHF, Hypovolemia)
Dehydrated
Accelerated catabolism (ill, trauma)
RX (CCS, tetracycline)
Dipstick protein is sensitive to?
Albumin mostly (No Bence-jones)
Granular casts can be ass/w?
ATN - Nonspecific, correlate
DS nitrite is from?
Nitrate to nitrite reduction from GNB (E.Coli esp)
NL Scr range is?
0.5-1.2mg/dL
Decreased BUN:Creatinine ratio is due to?
Intrinsic DZ like (ATN-AIN)
Broad casts are essentially formed by?
Dilated/atrophic tubules