Hematuria
Siegfried Schmidt and Ku-Lang Chang
Hematuria, defined as “blood in the urine,” is encountered frequently in family practice. It can occur as gross (macroscopic) hematuria with obvious reddish discoloration or can be seen microscopically, detected only with dipstick or microscopic examination. Routine urinalysis in 1,000 men aged between 18 and 33 years reported a 40% incidence (1). The extent of the workup can be determined by considering factors such as the likelihood of association with a severe underlying illness, complications of procedures, and expenses affecting the patient.
Approach
A. General approach. The overall objective dealing with hematuria is to discover potentially serious diseases (including glomerulonephritis and malignancies). In general, the degree of hematuria is of little diagnostic or prognostic value. As little as 1 ml of blood can cause a visible color change. In addition, a variety of drugs, foods, and food coloring can discolor the urine. The use of a benzidine dipstick allows differentiation of these discolorations from those of hematuria and myoglobinuria. The timing of hematuria during micturition can be helpful.
Other associated symptoms will help to narrow the diagnosis and direct the workup. A detailed history is essential and it will help pinpoint other causes of hematuria (e.g., specific drugs, parasites, and congenital or hereditary factors). It is helpful to know that hematuria in the adult is more often urologic than nephritic in origin. Mariani and Mariani determined the cause for asymptomatic, isolated hematuria in 1,000 adult cases and found that only 1.5% were glomerular in origin; 75% were caused by urethritis, prostate disease, bladder malignancies, and cystitis (2). Strategies for further diagnostic tests depend on the history and physical examination findings, which should give some idea as to whether the cause is nephritic, renal parenchymal, urologic, extrarenal in origin.
B. Red flags. Painless gross hematuria in an elderly man, in the absence of infection, is caused by a malignancy until proved otherwise. Hematuria associated with “sterile” pyuria is genitourinary tuberculosis or interstitial nephritis until proved otherwise. The presence of hematuria in patients on anticoagulation treatment warrants a complete evaluation. To avoid missing a malignancy, repeat evaluations are indicated for those patients in whom a malignancy is suspected (mainly older adults) and for those with a negative evaluation. The time interval is subject to debate and a reasonable time frame appears to be 3 to 6 months for less invasive tests and 1 year for more invasive tests (3).
History
A thorough history is of utmost importance!
A. General aspects
1. Type of hematuria (macro/gross or microscopic).
2. Relationship to urination or timing of hematuria. The three-container method will help to separate the micturition into three portions with an initial, middle, and final portion.
Predominantly, initial hematuria results from anterior urethral disease; final hematuria results from disease of the bladder neck or posterior urethra; and hematuria throughout the stream suggests a disease site higher in the bladder, ureter, or kidney.
3. Urine color. Color can be affected by the following: Phenazopyridine (orange); nitrofurantoin (brown); rifampin (yellow-orange); l-dopa, methyldopa, and metronidazole (reddish-brown); phenolphthalein in laxatives, red beet and rhubarb consumption, food coloring, and vegetable dyes (red).
4. Clots, especially wormlike clots, suggest a location above the bladder neck.
5. Associated symptoms (e.g., recent sore throat, fever, chills, and flulike symptoms) may be the first sign of IgA nephropathy or postinfectious glomerulonephritis. Urinary frequency, dysuria, fever, chills, and urgency point to an infectious process. Diminished urine flow and abdominal pain or flank pain radiating into the groin can indicate the presence of urinary tract obstruction (Chapter 10.5). Vaginal discharge or bowel movement changes may hint at a nonurinary tract cause such as a foreign body (especially in children). A rash, joint pain, photosensitivity, flulike symptoms, and Raynaud’s phenomenon point to a collagen vascular disease.
B. Past medical history should lead to a suspicion of parasites (e.g., Schistosoma heamatobium) if the patient has traveled to endemic areas; of bladder tumor if there was exposure to chemical carcinogens (e.g., aniline dyes), or tobacco smoke. Other causes of hematuria detected in the history include drug ingestion and anticoagulation, and medical problems such as prostatic hypertrophy, diabetes mellitus (nephrosclerosis), analgesic medication abuse (renal papillary necrosis), nephrolithiasis, trauma (including vigorous masturbation), chemotherapy exposure with cyclophosphamide (chemical cystitis), antibiotic use (interstitial nephritis), previous urinary tract malignancies suggesting recurrence, and sickle cell disease (papillary necrosis).
C. Family history. Delineate any family history of polycystic kidney disease, sickle cell trait and disease, nephrolithiasis, various glomerular diseases, tuberculosis, and benign familial hematuria. The combination of renal failure, deafness, and hematuria suggests Alport’s hereditary nephritis.
Physical examination
should focus on signs of systemic disease (fever, rash, lymphadenopathy, joint swelling, and abdominal or pelvic mass), and underlying medical or renal disease (hypertension, edema). Multiple telangiectasias and mucous membrane lesions indicate hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber disease). An abdominal mass in children requires exclusion of Wilms tumor.
Testing
A. Initial evaluation. Hematuria is usually detected by dipstick or microscopic examination. The dipstick test relies on detecting hemoglobin and should always be confirmed by microscopic examination of the urine sediment. Some controversy exists about the abnormal number of red blood cells in urine. Most clinicians consider more than three to five red blood cells per high power field (40 × lens) as definitely abnormal. When dipstick testing is positive for blood but urine microscopy reveals no red blood cells, hemoglobinuria or myoglobinuria should be considered. The next step is a urine culture. Baseline blood tests include a renal panel, complete blood count with differential, sedimentation rate, prothrombin time, and partial thromboplastin time.
B. Further evaluation is highly dependent on the suspected cause. Further blood tests can include serum complement titer (significant if low), antistreptolysin-O titer (high), antinuclear antibody and extended panels with anti-deoxyribonuclease B titer (high), and hemoglobin electrophoresis. A tuberculin skin test or chest x-ray study can be done to detect tuberculosis. Further tests can include imaging studies and cytology. Intravenous pyelogram and abdominal and pelvic ultrasound or computed tomography scanning may detect malignancies of the various anatomic areas as well as benign conditions such as urolithiasis, obstructive uropathy, renal cysts, parenchymal abnormalities, and nonurinary tract lesions. To complete the workup, send the urine for cytology study and proceed with cystoscopy looking for abnormalities of the urethra and bladder. Biopsies of various areas, including kidney and bladder, and invasive vascular studies may be needed. Unless a diagnosis is made, patients will need referral to subspecialists.
Diagnostic assessment
The key to the diagnosis of hematuria is the clinical history and physical examination. Laboratory and imaging studies only confirm or rule out initial suspicions. The goal is to diagnose a variety of serious illnesses, including malignancies and renal parenchymal diseases. In general, keep in mind that transient hematuria, especially in a young person, is quite common and rarely indicative of significant pathology (4). When present in patients aged more than 50 years, however, transient hematuria always warrants a comprehensive evaluation to rule out malignancy. Similarly, a diagnostic workup should be performed when persistent hematuria is found in patients of any age.
References
1. Froom P, Ribak J, Benbassat J. The significance of microhematuria in young adults. BMJ 1984;288:20–28.
2. Mariani AJ, Mariani MC. The significance of adult hematuria: 1000 hematuria evaluations including a risk-benefit and cost-effectiveness analysis. J Urol 1989;
141:350–355.
3. Messing EM, Young TB, Hunt VB, et al. Hematuria home screening: repeat testing results. J Urol 1995;154(1):57–61.
4. Murakami S, Igarashi T, Hara S, et al. Strategies for asymptomatic microscopic hematuria: a prospective study of 1034 patients. J Urol 1990;144:99–106.
Book Source Details
- Book Title: The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter
- Author(s): Robert B. Taylor (editor)
- Year of Publication: 2000
- Copyright Details: The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter, Copyright © 2000 Lippincott Williams & Wilkins.
Other Book Chapters Related to Kidney symptoms
Read excerpts from these other book chapters related to Kidney symptoms:
Medical Books Excerpts
- HEMATURIA
- "Algorithmic Diagnosis of Symptoms and Signs" (2003)
- [ read ]
- Hematuria
- "In A Page: Pediatric Signs and Symptoms" (2007)
- [ read ]
- HEMATURIA
- "Differential Diagnosis in Primary Care" (2007)
- [ read ]
- Hematuria
- "Handbook of Signs & Symptoms (Third Edition)" (2006)
- [ read ]
- Hematuria
- "A Pocket Manual of Differential Diagnosis" (1999)
- [ read ]
- Hematuria
- "Professional Guide to Signs & Symptoms (Fifth Edition)" (2006)
- [ read ]
- Hematuria
- "The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter" (2000)
- [ read ]
- Hematuria
- "Signs & Symptoms: A 2-in-1 Reference for Nurses" (2007)
- [ read ]
- Hematuria
- "The Diagnostic Approach to Symptoms and Signs in Pediatrics" (2006)
- [ read ]
- Hematuria
- "Nursing: Interpreting Signs and Symptoms" (2007)
- [ read ]
- HEMATURIA
- "Differential Diagnosis in Primary Care" (2007)
- [ read ]
Copyright Details: The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter, Copyright © 2008 Williams & Wilkins.
More About Causes of Kidney symptoms
» Next page: Hematuria (Field Guide to Bedside Diagnosis)
Rate This Website
What do you think about the features of this website?
Take our user survey and have your say:
Website User Survey
Medical Tools & Articles:
Next articles:
Tools & Services:
Medical Articles:
Forums & Message Boards
- Ask or answer a question at the Boards:
