- Author: Sanjeev Gulati, MD, MBBS, DNB(Peds), DM, DNB(Neph), FIPN(Australia), FICN, FRCPC(Canada); Chief Editor: Craig B Langman, MD more...
Generally, hematuria is defined as the presence of 5 or more red blood cells (RBCs) per high-power field in 3 of 3 consecutive centrifuged specimens obtained at least 1 week apart. Hematuria can be either gross (ie, overtly bloody, smoky, or tea-colored urine) or microscopic. It may also be either symptomatic or asymptomatic, either transient or persistent, and either isolated or associated with proteinuria and other urinary abnormalities. See the image below.
Signs and symptoms
The first step in the evaluation of hematuria consists of a detailed history and a thorough physical examination. Efforts should be made to distinguish glomerular causes from extraglomerular ones, as follows:
Passage of clots in urine suggests an extraglomerular cause
Fever, abdominal pain, dysuria, frequency, and recent enuresis in older children may point to a urinary tract infection as the cause
Recent trauma to the abdomen may be indicative of hydronephrosis
Early-morning periorbital puffiness, weight gain, oliguria, dark-colored urine, and edema or hypertension suggest a glomerular cause
Hematuria due to glomerular causes is painless
Recent throat or skin infection may suggest postinfectious glomerulonephritis
Joint pains, skin rashes, and prolonged fever in adolescents suggest a collagen vascular disorder
Anemia cannot be accounted for by hematuria alone; in a patient with hematuria and pallor, other conditions should be considered
Information regarding exercise, menstruation, recent bladder catheterization, intake of certain drugs or toxic substances, or passage of a calculus may also assist in the differential diagnosis
A family history that is suggestive of Alport syndrome, collagen vascular diseases, urolithiasis, or polycystic kidney disease is important
Physical examination should include the following:
Measurement of the blood pressure (with an appropriately sized cuff)
Evaluation for the presence of periorbital puffiness or peripheral edema
Detailed skin examination to look for purpura.
Abdominal examination to look for palpable kidneys
Careful examination of the genitalia
Detailed ophthalmologic evaluation (in familial hematuria)
The following findings help distinguish between glomerular and nonglomerular hematuria:
Glomerular hematuria: Brown-colored urine, RBC casts, and dysmorphic (small, deformed, misshapen, sometimes fragmented) RBCs and proteinuria
Nonglomerular hematuria: Reddish or pink urine, passage of blood clots, and eumorphic (normal-sized, biconcavely shaped) erythrocytes
See Clinical Presentation for more detail.
The laboratory tests ordered for the evaluation of hematuria must be based on the clinical history and the physical examination. Tests that may be helpful include the following:
Urinalysis with careful microscopic review of the urine sample
Phase-contrast microscopy to help determine the source of the bleeding
Blood urea nitrogen (BUN) and serum creatinine levels
Hematologic and coagulation studies (eg, complete blood count [CBC] and, sometimes, platelet counts)
Urine calcium excretion
Serologic testing (eg, complement, antistreptolysin [ASO], anti-DNase B, antinuclear antibody [ANA], and double-stranded DNA [dsDNA])
Urine culture for suspected urinary tract infection (UTI)
The following imaging studies may be helpful:
Renal and bladder ultrasonography
IV urography rarely contributes additional information in the evaluation of hematuria and may result in unnecessary exposure to ionizing radiation.
A kidney biopsy is rarely indicated in the evaluation of isolated asymptomatic hematuria. Relative indications for performing a kidney biopsy in patients with hematuria are as follows:
Abnormal renal function
Recurrent persistent hematuria
Serologic abnormalities (abnormal complement, ANA, or dsDNA levels)
Recurrent gross hematuria
A family history of end-stage renal disease
In most patients, a renal biopsy either is normal or reveals minor changes, such as thin glomerular basement membranes, focal glomerulonephritis, or mild mesangial hypercellularity. In a minority of patients, histologic findings, together with historical or serologic data, may point to specific conditions.
Patients with hematuria may usefully be categorized into 1 of the following 4 groups:
Microscopic hematuria with clinical symptoms
Asymptomatic microscopic hematuria with proteinuria
Asymptomatic microscopic (isolated) hematuria
See Workup for more detail.
General principles of treatment are as follows:
Hematuria is a sign and not itself a disease; thus, therapy should be directed at the process causing it
Asymptomatic (isolated) hematuria generally does not require treatment
In conditions associated with abnormal clinical, laboratory, or imaging studies, treatment may be necessary, as appropriate, with the primary diagnosis
Surgical intervention may be necessary with certain anatomic abnormalities (eg, ureteropelvic junction obstruction, tumor, or significant urolithiasis)
Dietary modification is usually not indicated, except for children who may tend to develop hypertension or edema as a result of the primary disease process (eg, nephritis)
Patients with persistent microscopic hematuria should be monitored every 6-12 months for the appearance of signs or symptoms indicative of progressive renal disease
Guidelines on hematuria from the American College of Physicians (ACP) advises that clinicians should include gross hematuria in their routine review of systems and specifically ask all patients with microscopic hematuria about any history of gross hematuria.[1, 2]
The ACP also recommend that[1, 2] :
Clinicians should not use screening urinalysis for cancer detection in asymptomatic adults.
Clinicians should confirm heme-positive results of dipstick testing with microscopic urinalysis that demonstrates 3 or more erythrocytes per high-powered field before initiating further evaluation in all asymptomatic adults.
Clinicians should refer for further urologic evaluation in all adults with gross hematuria, even if self-limited.
Clinicians should consider urology referral for cystoscopy and imaging in adults with microscopically confirmed hematuria in the absence of some demonstrable benign cause.
Clinicians should pursue evaluation of hematuria even if the patient is receiving antiplatelet or anticoagulant therapy.
Clinicians should not obtain urinary cytology or other urine-based molecular markers for bladder cancer detection in the initial evaluation of hematuria.
Hematuria is one of the most common urinary findings that result in children presenting to pediatric nephrologists. Generally, hematuria is defined as the presence of 5 or more RBCs per high-power field in 3 of 3 consecutive centrifuged specimens obtained at least 1 week apart. In the office setting, a positive reaction on the urine dipstick test is usually the first indication of the presence of hematuria. Hematuria can be gross (ie, the urine is overtly bloody, smoky, or tea colored) or microscopic. It may be symptomatic or asymptomatic, transient or persistent, and either isolated or associated with proteinuria and other urinary abnormalities. The role of the primary care physician in the management of a child with hematuria includes the following:
Recognize and confirm the finding of hematuria.
Identify common etiologies.
Select patients who have significant urinary system disease that might require further expertise in either diagnosis or management and referral.
The etiology and pathophysiology of hematuria vary. For instance, hematuria of glomerular origin may be the result of a structural disruption in the integrity of glomerular basement membrane caused by inflammatory or immunologic processes. Chemicals may cause toxic disruptions of the renal tubules, whereas calculi may cause mechanical erosion of mucosal surfaces in the genitourinary tract, resulting in hematuria.
The prevalence of gross hematuria in children is estimated to be 0.13%. In more than half of the cases (56%) this is due to an easily identifiable cause. The most common cause appears to be cystitis (20-25%). Asymptomatic microscopic hematuria is, on the average, 10-fold as prevalent as gross hematuria (1.5%, range 0.4-4.1%, depending on the criteria used to define hematuria). With repeated evaluations, the prevalence of asymptomatic microscopic hematuria decreases to less than 0.5%, supporting the notion that most cases of hematuria in children are transient. The incidence of simultaneous hematuria and proteinuria is estimated to be only 0.06%, but their coexistence signals significant renal disease.
In general, children with isolated asymptomatic microscopic hematuria tend to do well, whereas those with associated findings (eg, hypertension, proteinuria, abnormal serum creatinine levels) are more likely to have serious problems. Because hematuria is the end result of various processes, the morbidity and mortality rates of the condition depend on the primary process that initiated it.
The incidence of hematuria in specific racial groups is determined by the primary cause. For example, idiopathic hypercalciuria is infrequent in black and Asian children, but relatively common in whites. Conversely, hematuria caused by sickle cell disease is more common in blacks than in whites.
Sex may predispose a child to specific diseases that manifest as hematuria. For example, the sex-linked form of Alport syndrome has a male preponderance, whereas lupus nephritis is more common in adolescent girls.
Prevalence of certain conditions varies with age. For instance, Wilms tumors are more frequent in children of preschool age, whereas acute postinfectious glomerulonephritis is more frequent in the school-aged population. In adults, hematuria is often a sign of malignancy of the genitourinary tract (eg, renal cell carcinoma, bladder tumors, prostatic tumors). These conditions are rare in children.
Nielsen M, Qaseem A, High Value Care Task Force of the American College of Physicians. Hematuria as a Marker of Occult Urinary Tract Cancer: Advice for High-Value Care From the American College of Physicians. Ann Intern Med. 2016 Jan 26. [Medline].
Phillips D. Clinical Guideline on Hematuria Released by ACP. Medscape Medical News. Available at http://www.medscape.com/viewarticle/857888. January 28, 2016; Accessed: February 8, 2016.
Tu WH, Shortliffe LD. Evaluation of asymptomatic, atraumatic hematuria in children and adults. Nat Rev Urol. 2010 Apr. 7(4):189-94. [Medline].
Higashihara E, Nishiyama T, Horie S, et al. Hematuria: definition and screening test methods. Int J Urol. 2008 Apr. 15(4):281-4. [Medline].
Quigley R. Evaluation of hematuria and proteinuria: how should a pediatrician proceed?. Curr Opin Pediatr. 2008 Apr. 20(2):140-4. [Medline].
Kashtan CE. Familial hematuria. Pediatr Nephrol. 2009 Oct. 24(10):1951-8. [Medline].
Diven SC, Travis LB. A practical primary care approach to hematuria in children. Pediatr Nephrol. 2000 Jan. 14(1):65-72. [Medline].
Dodge WF, West EF, Smith EH, Bruce Harvey 3rd. Proteinuria and hematuria in schoolchildren: epidemiology and early natural history. J Pediatr. 1976 Feb. 88(2):327-47. [Medline].
Friedlander DF, Resnick MJ, You C, Bassett J, Yarlagadda V, Penson DF, et al. Variation in the intensity of hematuria evaluation: a target for primary care quality improvement. Am J Med. 2014 Jul. 127 (7):633-640.e11. [Medline].
Boughton B. Microscopic hematuria may be poor predictor of cancer. Medscape Medical News. January 10, 2013. Available at http://www.medscape.com/viewarticle/777505. Accessed: March 18, 2013.
Crompton CH, Ward PB, Hewitt IK. The use of urinary red cell morphology to determine the source of hematuria in children. Clin Nephrol. 1993 Jan. 39(1):44-9. [Medline].
Cruz CC, Spitzer A. When you find protein or blood in the urine. Contemp Pediatr. 1998. 15:89-109.
Cybulsky AV, Walsh M, Knoll G, Hladunewich M, Bargman J, Reich H, et al. Canadian Society of Nephrology Commentary on the 2012 KDIGO clinical practice guideline for glomerulonephritis: management of glomerulonephritis in adults. Am J Kidney Dis. 2014 Mar. 63(3):363-77. [Medline].
D'Amico G. The commonest glomerulonephritis in the world: IgA nephropathy. Q J Med. 1987 Sep. 64(245):709-27. [Medline].
Emancipator SN, Gallo GR, Lamm ME. IgA nephropathy: perspectives on pathogenesis and classification. Clin Nephrol. 1985 Oct. 24(4):161-79. [Medline].
Feld LG, Stapleton FB, Duffy L. Renal biopsy in children with asymptomatic hematuria or proteinuria: survey of pediatric nephrologists. Pediatr Nephrol. 1993 Aug. 7(4):441-3. [Medline].
Feld LG, Waz WR, Perez LM, Joseph DB. Hematuria. An integrated medical and surgical approach. Pediatr Clin North Am. 1997 Oct. 44(5):1191-210. [Medline].
Kalia A, Travis LB, Brouhard BH. The association of idiopathic hypercalciuria and asymptomatic gross hematuria in children. J Pediatr. 1981 Nov. 99(5):716-9. [Medline].
Kincaid-Smith P, Fairley K. The investigation of hematuria. Semin Nephrol. 2005 May. 25(3):127-35. [Medline].
Krieger I, Sargent DA. A postural sign in the sensory deprivation syndrome in infants. J Pediatr. 1967 Mar. 70(3):332-9. [Medline].
Loo RK, Lieberman SF, Slezak JM, Landa HM, Mariani AJ, Nicolaisen G, et al. Stratifying risk of urinary tract malignant tumors in patients with asymptomatic microscopic hematuria. Mayo Clin Proc. 2013 Feb. 88(2):129-38. [Medline].
Meyers KE. Evaluation of hematuria in children. Urol Clin North Am. 2004 Aug. 31(3):559-73, x. [Medline].
Roy S 3rd. Hematuria. Pediatr Rev. 1998 Jun. 19(6):209-12; quiz 213. [Medline].
Samuel S, Bitzan M, Zappitelli M, et al. Canadian Society of Nephrology Commentary on the 2012 KDIGO clinical practice guideline for glomerulonephritis: management of nephrotic syndrome in children. Am J Kidney Dis. 2014 Mar. 63(3):354-62. [Medline].
Sargent JD, Stukel TA, Kresel J, Klein RZ. Normal values for random urinary calcium to creatinine ratios in infancy. J Pediatr. 1993 Sep. 123(3):393-7. [Medline].
Seigel M, Lee ML. Hematuria. Semin Arthritis Rheum. 1974. 3:1.
Ward JF, Kaplan GW, Mevorach R, et al. Refined microscopic urinalysis for red blood cell morphology in the evaluation of asymptomatic microscopic hematuria in a pediatric population. J Urol. 1998 Oct. 160(4):1492-5. [Medline].
Yadin O. Hematuria in children. Pediatr Ann. 1994 Sep. 23(9):474-8, 481-5. [Medline].
|Systemic lupus erythematosus||Mild glomerulitis, proliferative changes, immune complex deposition, crescents, immunoglobulin deposition||Hematuria, proteinuria, hypertension, joint pains, rashes||Abnormal C3, C4, ANA, and dsDNA levels; anemia; thrombocytopenia|
|IgA nephropathy||IgA deposition in the mesangium, glomerular sclerosis, proliferative changes, crescents in severe cases||Gross, intermittent, painless hematuria||No specific changes, although increased serum
IgA levels observed in some patients
|Henoch-Schönlein purpura||Same as IgA nephropathy||Purpura, joint pains, abdominal pain, hematuria||No specific laboratory data|
|Alport syndrome||Some thinning of basement membranes, "basket weave" changes in the glomerular basement
membrane on electron microscopy
|Sensorineural hearing loss, corneal abnormalities, hematuria, renal failure||No specific changes|
|Thin basement membrane disease||Average glomerular basement membranes reported to be 100-200 nm in children in this condition||Persistent microscopic or gross hematuria, significant family history||No specific changes|
|Mesangiocapillary glomerulonephritis||Glomerular lobulations, thickening of the mesangial matrix and glomerular basement membranes, crescents||Hematuria, proteinuria, hypertension||C3 levels possibly abnormal|