A 65-year-old man comes to the office after noticing blood in his urine. He has had 2 similar episodes of bloody urine over the last month that cleared spontaneously. He has had no abdominal pain, dysuria, or recent illness. The patient has a 30-pack-year smoking history but quit 10 years ago. He has a history of hypertension and has had a transient ischemic attack. Temperature is 36.7 C (98 F), blood pressure is 130/86 mm Hg, pulse is 80/min, and respirations are 16/min. Physical examination, including digital rectal examination, is unremarkable. Laboratory results are as follows: Which of the following is the most likely cause of this patient's symptoms?

Question

A 65-year-old man comes to the office after noticing blood in his urine.  He has had 2 similar episodes of bloody urine over the last month that cleared spontaneously.  He has had no abdominal pain, dysuria, or recent illness.  The patient has a 30-pack-year smoking history but quit 10 years ago.  He has a history of hypertension and has had a transient ischemic attack.  Temperature is 36.7 C (98 F), blood pressure is 130/86 mm Hg, pulse is 80/min, and respirations are 16/min.  Physical examination, including digital rectal examination, is unremarkable.  Laboratory results are as follows:  Which of the following is the most likely cause of this patient's symptoms?

Quizplus · Accepted Answer

Explanation: This patient has hematuria, which is defined as ≥3 red blood cells/hpf on urinalysis. Because hematuria is caused by a variety of benign and malignant conditions, additional testing (eg, cystoscopy, abdominal CT scan) is often required for differentiation of the underlying etiology. However, urinalysis findings, the presence or absence of pain during urination, and the age of the patient typically raises suspicion for a particular disease state, as follows: Bladder cancer generally arises from malignant transformation of the bladder surface epithelium (urothelium) due to chronic exposure to chemical carcinogens, particularly those found in tobacco smoke and industrial chemicals. Therefore, most cases arise in older individuals who smoke or who have workplace exposure to carcinogens. A common presentation is painless hematuria due to bleeding from friable blood vessels supplying the tumor. Bladder infections cause inflammation of the bladder epithelium, which can lead to hematuria. However, most cases are associated with suprapubic pain, dysuria, and signs of infection on urinalysis (eg, pyuria, positive leukocyte esterase, bacteriuria) (Choice C). Ureterolithiasis causes direct epithelial injury (scraping of epithelium by stone), which can result in hematuria. However, most cases are associated with pain (eg, flank pain that radiates to the groin), and crystals are sometimes seen on urinalysis (Choice F). Glomerulonephritis increases the permeability of the glomerulus, which allows RBCs to pass into the urinary tract from the circulatory system. However, most cases are associated with RBC casts, proteinuria, and (sometimes) a preceding upper respiratory infection (eg, postinfectious glomerulonephritis) (Choice A). This patient's advanced age, history of tobacco use, painless hematuria, absence of dysuria/bacteriuria/leukocyte esterase (signs of infection), and casts (sign of glomerular injury) raise suspicion for bladder cancer. (Choice D) Prostate cancer rarely causes hematuria because it generally grows in the periphery (not the central periurethral area) of the gland. In contrast, benign prostatic hyperplasia is often associated with hematuria because it primarily occurs in the periurethral area. (Choice E) Rhabdomyolysis can cause reddish-brown urine (resembles blood) due to myoglobinuria. Although myoglobinuria usually causes positive blood on urinalysis (this test detects heme), no RBCs would be seen. Educational objective: Bladder tumors are a common cause of painless hematuria in older adults, particularly in those who have used tobacco. References: Stratifying risk of urinary tract malignant tumors in patients with asymptomatic microscopic hematuria. (http://www.ncbi.nlm.nih.gov/pubmed/23312369) A prospective analysis of 1,930 patients with hematuria to evaluate current diagnostic practice. (http://www.ncbi.nlm.nih.gov/pubmed/10647670)

A 65-Year-Old Man Comes to the Office After Noticing Blood