Clinical aspects of hematuria

Question 1

Overview of hematuria

Answer 1

• A count of >3 RBC/HPF (high power field) is positive for hematuria
• Looks brown-red, coffee colored
• Transient hematuria is common and in younger pts is usually benign
• In older pts transient hematuria may indicate malignancy
• Hematuria may occur after physical activity
• Could be from contamination by menstrual blood
• Not all red urine is hematuria, first check dipstick to see if RBCs are present

Question 2

Lesions along urinary tract that could cause hematuria

Answer 2

• Neoplasms of bladder, ureter, or prostate
• Stones anywhere
• UTI, prostatitis
• BPH
• Hemorrhagic cystitis (cyclophosphamide) or radiation cystitis
• Catheter
• Anticoag

Question 3

Renal causes of hematuria

Answer 3

• Can be glomerular or non-glomerular
• Non-glomerular: tumors, SCD, renal vein thrombosis, hypercalcemia, renal malformations (PCKD, medullary sponge kidney), infection, drugs, trauma
• Glomerular: isolated or nephritic syndrome
• Isolated causes are either IgA or inherited diseases (thin basement membrane for women, Alport’s syndrome in men-X linked)
• Nephritic syndrome consists of: hematuria, proteinuria not nephrotic range), reduced renal function, HTN
• Causes of nephritic syndrome include SLE nephritis, post-infectious GN, IgA, anti-GBM/goodpasture’s, membranoproliferative GN

Question 4

Thin basement membrane

Answer 4

• Benign familial hematuria mostly affecting women
• Mutations in type 4 collagen alpha chain 4
• Only Sx is hematuria

Question 5

Alport’s syndrome

Answer 5

• X linked thus mostly affecting males
• Mutations in type 4 collagen alpha chains 3, 4, and 5
• Associated w/ deafness, proteinuria and HTN
• Progresses to ESRD

Question 6

Complement levels in various forms of nephritic syndrome

Answer 6

• Low serum complement (complement depleted): SLE, post-infectious GN, membranoproliferative GN (MPGN)
• Normal serum complement: IgA, anti-GBM/goodpasture’s

Question 7

Localization of hematuria

Answer 7

• May be glomerular or extra-glomerular
• Glomerular hematuria usually presents w/ brown/red urine and often a more severe proteinuria (>500 mg/day)
• There are dysmorphic RBCs (bleb and RBC casts
• In extraglomerular hematuria the urine is red or pink, proteinuria is less severe (<500 mg/day)
• There are usually no dysmorphic RBCs or RBC casts

Question 8

Risk factors for significant disease

Answer 8

• Smoking, exposure to chemicals/dyes
• Hx of gross hematuria
• Old age (>40)
• Analgesic abuse
• Pelvic radiation
• Cyclophosphamide use

Question 9

Dx studies for hematuria

Answer 9

• Intravenous pyelogram (IVP), ultrasound, CT scan
• Renal biopsy indicated if findings suggest intrinsic renal disease (positive urine sediment, proteinuria) and factors associated w/ poor prognosis (proteinuria >1g/day, elevated Cr)