4 - Hematuria

Authors: Macfarlane, Michael T.

Title: Urology, 4th Edition

Copyright 2006 Lippincott Williams & Wilkins

> Table of Contents > Part One - Chief Presentations > Chapter 4 - Hematuria

Chapter 4

Hematuria

Hematuria, whether microscopic or gross, is a red flag that demands careful evaluation and must not be ignored. It is the most common presenting sign of urinary tract cancer and parenchymal renal disease. Because of the seriousness of missing a diagnosis of cancer, most urologists have a low threshold for working up any significant hematuria.

Significant Hematuria

As few as three red blood cells (RBCs) per high power field (hpf) in a voided specimen from an adult male is considered significant. RBCs found in the urine can be differentiated into two types based on origin: epithelial RBCs and glomerular RBCs.

Epithelial RBCs are regular, with smooth, rounded, or crenated membranes and an even hemoglobin distribution. As few as one epithelial RBC per hpf is abnormal and is considered a sign of urologic disease.

Glomerular RBCs are dysmorphic with irregular shapes and cell membranes and minimal or uneven hemoglobin distribution. More than 1 million RBCs normally escape from the glomerular capillaries into the urine every 24 hours. The cells become dysmorphic because of the osmotic stresses experienced during passage through the nephron. A level of more than 2 RBCs per hpf is abnormal and suggests glomerular disease.

Differential Diagnosis

Qualifying the type of hematuria and any associated symptoms can narrow the differential diagnosis of hematuria. Bright red gross, or macroscopic, hematuria is usually of lower urinary tract origin, whereas renal parenchymal bleeding is usually smoky, hazy, or reddish-brown owing to the formation of acid hematin in urine of low pH. Proteinuria out of proportion to the degree of hematuria (i.e.,

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>2+ protein on dipstick or >1 g/24-hour urine with microscopic hematuria) suggests a renal parenchymal origin (e.g., glomerulonephritis). An active urine sediment (e.g., red cell casts or granular casts) also suggests a renal parenchymal origin. Medical hematuria (e.g., renal parenchymal disease excluding tumors) is suggested by the presence of glomerular RBCs, an active urinary sediment, and significant proteinuria. Surgical hematuria is suggested by epithelial RBCs, no casts, and minimal proteinuria.

Major Diagnosis Groups

  • Cancer

  • Infection

  • Stones

  • Benign prostatic hyperplasia

  • Renal parenchymal lesions

  • Trauma

  • Benign idiopathic hematuria

Workup

History

Silent or painless hematuria suggests tumor or renal parenchymal disease. Irritative voiding symptoms (e.g., frequency, urgency, dysuria) suggest infection; however, a bladder tumor should be suspected if cultures are negative. Colicky pain suggests stone passage or sloughed renal papillae. Ask about onset and duration; associated pain; a history of trauma; and family history of diabetes, sickle cell disease, polycystic disease, or renal stones. Cyclic hematuria occurring with menses in females suggests endometriosis. Hematospermia is generally insignificant in young males; however, it can be associated with carcinoma of the prostate involving the seminal vesicle in older men. Initial hematuria suggests anterior urethral bleeding, whereas terminal hematuria is more consistent with posterior urethral bleeding (e.g., prostate or bladder neck). Total hematuria indicates bleeding at the level of the bladder or above.

Physical Examination

Fever of higher than 101 F strongly suggests a serious infection (e.g., pyelonephritis or prostatitis). Palpate the abdomen for evidence

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of a mass. A palpable kidney suggests tumor or hydronephrosis. A palpable bladder may indicate obstruction or retention. An irregular heart rate (from atrial fibrillation) associated with flank pain and hematuria should raise the possibility of renal embolic infarction.

Urinalysis

The urinalysis is a critical part of every workup. Differentiation of the type of hematuria (i.e., epithelial vs. glomerular) is best made using a phase contrast microscope; however, lowering the condenser on any microscope usually produces enough contrast to make the differentiation. The presence of white cells suggests an inflammatory process (e.g., infection, foreign body reaction, interstitial nephritis). The presence of casts and proteinuria suggests a medical renal parenchymal disease.

Urine Culture

A urine culture should be performed if significant pyuria or bacteriuria is present. Persistent isolated pyuria with negative cultures raises the question of tuberculosis.

Twenty-Four Hour Urine for Protein

The presence of proteinuria out of proportion to the degree of hematuria demonstrated by dipstick (i.e., >2+ protein with microhematuria) or a primary picture of glomerular bleeding should be followed by a 24-hour urine collection for quantitative protein.

Complete Blood Count

A complete blood count to detect the presence of anemia or leukocytosis should be considered.

Chemistries

Routine screening chemistries [sodium (Na), potassium (K), chloride (Cl), carbon dioxide (CO2), blood urea nitrogen (BUN), creatinine, glucose, albumin] should be performed to evaluate renal function and look for electrolyte abnormalities. A

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serum albumin should be conducted only if significant proteinuria is in question.

Intravenous Urogram

An intravenous urogram is a fundamental diagnostic test for a patient with surgical hematuria. It should generally be obtained before cystoscopy if the upper tracts need further delineation by retrograde ureteropyelography.

Computed Tomography Scan of Kidneys

A computed tomography (CT) scan of the kidneys should be performed first without intravenous contrast, followed by a scan with contrast. Renal parenchymal tumors are best identified by contrast-enhanced CT.

Cystoscopy

Cystoscopy is mandatory to fully evaluate surgical hematuria. Small bladder tumors are easily missed on the cystogram phase of the intravenous urogram (IVU) or pelvic CT scan.

Renal Biopsy

Renal biopsy is indicated for patients with evidence of medical renal parenchymal disease, abnormal renal function, and proteinuria in excess of 250 mg/day.

Acute Management of Severe Bladder Hemorrhage

Occasionally, patients will present with severe, intractable gross hematuria that must be controlled on an acute basis. Two of the most common causes are as follows:

  • Advanced bladder cancer. Patients may present with major intravesical bleeding from the tumor. The steady blood loss with slowly dropping hematocrit may necessitate transfusions, and clot formation in the bladder may cause retention.

  • Hemorrhagic cystitis secondary to cyclophosphamide chemotherapy and/or radiation.

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Treatment Options

  • Place a 22 to 26 F urethral catheter and hand irrigate with normal saline.

  • Start continuous bladder irrigation via a three-way Foley catheter (22 26 F) if active bleeding is minor.

  • If there is still significant active bleeding, perform cystoscopy. If there is a resectable bladder tumor, resect it. If the tumor is unresectable, attempt to coagulate any obvious areas of active bleeding.

  • Continuously irrigate intravesically with 1% alum (aluminum potassium sulfate) solution as needed.

  • Instill 1% silver nitrate solution intravesically.

  • Instill 1% to 4% formalin intravesically. (Note: formalin instillation is accompanied by a high complication rate and requires anesthesia; thus, it should be used only for serious bleeding that has failed more conservative modalities. It is contraindicated in the presence of vesicoureteral reflux; therefore, a voiding cystourethrogram must be obtained first.)

  • Embolize or ligate the iliac arteries and perform cystectomy.



Urology
Smiths General Urology, Seventeenth Edition (LANGE Clinical Medicine)
ISBN: 0071457372
EAN: 2147483647
Year: 2004
Pages: 44

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