Renal Flashcards
Causes of Elevated BUN (azotemia)
Prerenal: decreased renal perfusion (HF, renal artery stenosis, dehydration) & increased protein breakdown (diet, upper GI bleed)
Renal: acute/chronic renal failure
Post renal: obstruction of ureter/bladder neck
Causes of Decreased BUN
Severe liver disease, malnutrition (low protein diet), fluid overload (dilute out BUN levels)
SCr norm
0.6-1.2 mg/dL
Causes of Elevated SCr
Prerenal: decreased renal perfusion (HF, dehydration)
Renal: acute/chronic renal insufficiency
Causes of Decreased SCr
Prerenal: loss/lack of muscle mass (ELDERLY), severe liver dysfunction (cirrhosis)
Normal BUN/SCr ratio
Less than or equal to 20:1
BUN/SCr prerenal ratio
> 20:1
BUN/SCr renal/post renal ratio
10:1 or 20:1
CrCl norm
90-140 mL/min
Hazy yellow/cloudy urine indicates:
Infection
Froathy foam urine indicates:
Excess proteins
Red-orange urine indicates:
Myoglobin (rhabdomyolosis), hgb (hemolysis), RBCs (bleeding), drugs
Brown-black urine indicates:
Myoglobin, hgb, iron, drugs
Nitrite positive in urine indicates:
Bacteriuria (possible UTI)
Leukocyte Esterace positive in urine indicates:
Presence of “inflammation”
RBCs in urine Indicates:
Suggests kidney injury or damage to urinary tract
WBCs in urine indicates:
Suggest inflammation or infection
Tubular epithelial cells in urine indicates:
Suggests damage/inflammation to tubules of nephron
Hyaline cast
Clear = no renal disease
Cellular cast
Variable color = EARLY renal disease
Granular cast
Muddy brown = CHRONIC renal disease
Urine pH norm
4.5-8, deters bacterial colonization
Specific gravity (SG) norm range
1.010-1.025, ratio of urine density compared w/ water
Increased SG indicates:
Diabetes MELLITUS (glucose), nephrotic syndrome (proteins)
Decreased SG indicates:
Diabetes INSIPIDUS
Extrinsic urinalysis factors:
Glucose, ketones, bilirubin, urobilinogen, blood/hgb,
Intrinsic urinalysis factors:
Blood/hgb, nitrite, leukocyte esterace, protein
Glucose in the urine indicates:
Diabetes Mellitus
Ketones in the urine indicates:
Type 1 DM/specific diet
Bilirubin in the urine colors urine ______
Colors urine dark yellow/brown
Urobilinogen in the urine indicates:
Hemolytic anemia, hepatitis, liver injury
Hgb in urine indicates:
Severe hemolysis
Causes of Transient proteinuria:
Exercise, seizures, fevers, dehydration
Causes of Persistent proteinuria:
Specific disease state problem, decreased renal mass
Fraction of excreted sodium (%FeNa) norm
0.5%
Low FeNa (less than 1%) indicates:
Prerenal: azotemia (dehydration, volume depletion, CHF)
Hepatorenal syndrome
High FeNa (> 1%) indicates:
Acute tubular necrosis, SIADH, diuretics
BUN norm
8-23 mg/dL