Evaluation of visible hematuria

Visible (gross) hematuria is urine that is visibly discolored by blood or blood clot. It may present as urine that is red to brown, or as frank blood. As little as 1 mL of blood can impart color to 1 L of urine.

Visible hematuria, even when transient or asymptomatic, may indicate a significant disease process and always requires further investigation. Possible etiologies vary by age and the workup of visible hematuria differs among children, adults under the age of 35 years, and adults ages 35 years or older.

Patients with visible hematuria represent a higher-risk group for urologic malignancy than those presenting with nonvisible hematuria.[1]Nielsen M, Qaseem A. Hematuria as a marker of occult urinary tract cancer: advice for high-value care from the American College of Physicians. Ann Intern Med. 2016 Apr 5;164(7):488-97. https://annals.org/aim/fullarticle/2484287/hematuria-marker-occult-urinary-tract-cancer-advice-high-value-care http://www.ncbi.nlm.nih.gov/pubmed/26810935?tool=bestpractice.com [2]Kaag MG, Raman JD. Clinical guidelines: Clearing murky water - a guideline-based approach to haematuria. Nat Rev Urol. 2016 Apr 13;13(5):243-4. http://www.ncbi.nlm.nih.gov/pubmed/27071454?tool=bestpractice.com [3]Loo RK, Lieberman SF, Slezak JM, et al. Stratifying risk of urinary tract malignant tumors in patients with asymptomatic microscopic hematuria. Mayo Clin Proc. 2013 Jan 9;88(2):129-38. http://www.ncbi.nlm.nih.gov/pubmed/23312369?tool=bestpractice.com Visible hematuria is a presenting sign in more than 66% of patients with urologic cancer.[4]Edwards TJ, Dickinson AJ, Natale S, et al. A prospective analysis of the diagnostic yield resulting from 4020 patients at a protocol-driven haematuria clinic. BJU Int. 2006 Feb;97(2):301-5. http://www.ncbi.nlm.nih.gov/pubmed/16430634?tool=bestpractice.com The sensitivity of visible hematuria in revealing malignancy is significant: 0.83 for urothelial carcinoma of the bladder, 0.66 for ureteric carcinoma, and 0.48 in renal cell carcinomas.[5]Buntinx F, Wauters H. The diagnostic value of macroscopic haematuria in diagnosing urological cancers: a meta-analysis. Fam Pract. 1997 Feb;14(1):63-8. https://academic.oup.com/fampra/article/14/1/63/548718 http://www.ncbi.nlm.nih.gov/pubmed/9061347?tool=bestpractice.com In men ages >60 years, the positive predictive value of visible hematuria for urologic malignancy is 22.1%, and in women of the same age it is 8.3%.[6]Hicks D, Li CY. Management of macroscopic haematuria in the emergency department. Postgrad Med J. 2008 Oct;84(996):539-44. http://www.ncbi.nlm.nih.gov/pubmed/19017839?tool=bestpractice.com

Risk factors for urothelial carcinoma include:

• Male sex

• Age 35 years or older

• Smoking

• Exposures to benzene, aromatic amines, carcinogens, chemotherapy, or high doses of analgesics

• A history of:

  • Irritative voiding symptoms

  • Chronic urinary tract infection

  • Indwelling urinary catheter

  • Pelvic irradiation.