Genitourinary System Disorders

Genitourinary System Disorders

Charles R. Kiefer


This chapter includes the latest information on the diseases and disorders of the genitourinary (GU) tracts. Each entry is organized with a brief definition of the disorder and information regarding clinical presentation, laboratory findings, and limitations, if appropriate.



□ Who Should Be Suspected?

  • Suspected patients are older than age 40 years, more commonly males with a history of cigarette smoking, who present with hematuria (painless, intermittent, grossly visible, and present throughout micturition), or irritative voiding symptoms (frequency, urgency, dysuria) that suggest carcinoma in situ (CIS) of the bladder.

  • The association of pain with bladder cancer (located to the flank; suprapubic, hypogastric, and perineal; abdominal or right upper quadrant areas; bone pain; or headache/disordered cognitive function) can be signs of locally advanced or metastatic disease. Constitutional symptoms (fatigue, weight loss, anorexia, failure to thrive) are usually signs of advanced or metastatic disease and carry a poor prognosis.

  • The definitive diagnosis and staging of bladder cancer are by cystoscopy, beginning with a baseline evaluation of the bladder and uninvolved mucosa to record the number, size, location, appearance, and growth type (papillary or solid) of all lesions observed. Visible lesions can be biopsied or resected for histologic analysis.

□ Laboratory Findings

  • Urinalysis: A positive dipstick test (detecting one to two red cells per high-power field [HPF]) should be confirmed by microscopic analysis (below). Infection should be ruled out by a urine culture prior to further workup of hematuria.

  • Urine sediment: Hematuria is significant if there are greater than three red cells per HPF, present throughout micturition. The presence of dysmorphic red cells or casts suggests a glomerular origin, whereas normally formed red cells likely originate from infections, tumors, or obstructions/calculi. The specimen should be maintained at room temperature and examined within 30 minutes of collection.

  • Urine cytology: Urine cytologic analysis by fluorescence in situ hybridization (e.g., UroVysionTM FISH) can be a useful noninvasive aid both in the primary diagnosis of urothelial carcinoma and in monitoring tumor recurrence (occurring in about 70% of cases after initial treatments). UroVysionTM FISH is designed to detect certain numerical chromosomal abnormalities commonly associated with urothelial carcinoma (either amplifications of chromosomes 3, 7, and 17 or deletions of the 9p21 locus). Test sensitivity ranges from 69% to 87%, and specificity ranges from 89% to 96%.

  • Urine biomarkers: Several urine-based biomarkers have been approved for diagnosis or surveillance of patients with a history of the disease. However, their sensitivity is low, and their use is not recommended for an initial workup of a suspected case.

□ Limitations on Interpretation of the UroVysionTM FISH Test for Bladder Cancer

  • A positive result in the absence of clinical evidence of urothelial bladder cancer may indicate urothelial malignancies of other organs along the GU tract (kidney, ureter, prostate, or urethra).

  • A negative result in the presence of other signs or symptoms of urothelial carcinoma may suggest a false-negative test.


□ Who Should Be Suspected?

  • Prostate cancer tends to develop in men over age 50. In the early stage of the disease, most men have no symptoms directly linked to the cancer, but because the gland surrounds the prostatic urethra, changes in urinary function can occur with disease progression.

  • As a presenting symptom, a change in urinary function (frequency, urgency, nocturia, hesitancy) is the most common, but benign prostatic hyperplasia (BPH) figures into the differential diagnosis and is usually the cause.

  • Hematuria and hematospermia are uncommon symptoms but, if present, also are more likely to be caused by BPH. However, if occurring in older men, prostate cancer should be included in the differential diagnosis.

  • Bone pain, often in the vertebrae, pelvis, or ribs, if present, would indicate metastatic disease.

□ Early Detection

  • The two methods for early detection of suspected prostate cancer are the digital rectal examination for asymmetric areas of induration or nodules on the posterior and lateral aspects of the prostate gland and measurement of serum prostate-specific antigen (PSA). About 20% of early detections occur through a suspicious digital rectal examination and the remaining 80% through a suspicious PSA test. A definitive diagnosis of prostate cancer by either method of early detection is established by a positive biopsy, but a suspicious PSA test should be repeated before recommending a biopsy. Almost a third of patients will evidence a decline in PSA levels to baseline in approximately a month.

  • Screening of unsuspected cases for prostate cancer via the PSA test is controversial. Because of the low specificity of elevated PSA levels for prostate cancer versus BPH or prostatitis, the benefits of screening are outweighed by the harms of unnecessary treatment. Screening is not recommended by the U.S. Preventive Services Task Force (Grade “D,” 2012) and the Centers for Disease Control and Prevention. The American Society of
    Clinical Oncology and the American College of Physicians discourage screening in those expected to live less than another 10-15 years. The American Urological Association (AUA) recommends shared decisionmaking in those from age 55 to 69 and no more often than every 2 years.

□ Laboratory Findings

  • PSA testing: PSA levels normally correlate with age and prostate size, averaging 1 ng/mL for men under age 50 and 3 ng/mL for men over age 60. A value of 4.0 ng/mL is widely used as a cutoff for prostate cancer. There are two effective methods of enhancing the specificity of the PSA test—use of an age-based reference range and calculation of the free versus total PSA ratio. In addition, although there is some increase in PSA with age, certain changes in PSA levels over time (PSA velocity) can be informative.

    • ▼ Age-based reference range: A PSA reference range based on age should be calculated for each laboratory performing PSA testing.

    • PSA free versus total ratio: The risk of prostate cancer is increased if the ratio of free to total PSA is <10%.

    • PSA velocity: A PSA change of >0.35 ng/mL from a baseline value of 2.5-4 ng/mL or an annual change >0.75 ng/mL from a baseline >4.0 ng/mL should prompt investigation.

Suggested Reading

Tabayoyong W, Abouassaly R. Prostate cancer screening and the associated controversy. Surg Clin N Am. 2015;95:1023-1039.


□ Who Should Be Suspected?

  • Individuals with carcinoma of the renal pelvis or ureter are most likely to have hematuria (70-80% of cases) or flank pain (8-40%) stemming from obstruction of the ureter or ureteropelvic junction by a tumor mass. Other types of urinary tract symptoms (bladder irritation, constitutional symptoms) are less likely to be seen at diagnosis (<10%). Calculi or chronic infection may precede the squamous cell carcinomas. Because the entire urothelial surface is of the same embryologic origin, and affected by the same carcinogens excreted or activated in the urine, approximately 17% of patients will have a concurrent bladder cancer at presentation.

  • Middle-aged individuals with leukoplakia of the renal pelvis typically have recurrent episodes of renal or ureteric colic. In 90% of cases, the lesion is unilateral.

□ Laboratory Findings

  • Urine cytology, carcinoma of the renal pelvis or ureter: Low-grade urothelial malignancies of the upper tract usually do not generate a positive cytology in the urinary sediment, but higher-grade lesions may do so. Rather, radiologic imaging procedures and uteroscopy are the initial diagnostic tools for these suspected tumors.

  • Urine cytology, leukoplakia of the renal pelvis: In a cell block or Pap smear, the finding of sheets of desquamated keratinized epithelial cells in urine during an attack of renal colic is pathognomonic.

  • Flow cytometry, leukoplakia of the renal pelvis: High-grade (aneuploid) tumors can be detected in >90% of cases.



□ Who Should Be Suspected?

  • Candidates are men, generally older than 30 years, with moderate to severe lower urinary tract symptoms (LUTS: frequency, nocturia, hesitancy, urgency, weak stream) that gradually progress with time. Becoming more prevalent with age, LUTS is present in approximately 50% of men at age 50 and up to 80% of men at age 80.

  • A history and physical examination should include a digital rectal examination of the prostate. A urine culture and urinalysis for hematuria should be undertaken to rule out other or more serious disorders that could cause symptoms similar to those of BPH (urinary tract infection [UTI], bladder calculi, prostatitis, prostate cancer, or bladder cancer). On digital rectal examination, symmetric enlargement and firmness of the prostate are typical of BPH, whereas asymmetric areas are suggestive of prostate cancer.

□ Laboratory Findings

  • Serum PSA: In 20% of BPH patients, serum PSA may be increased from the widely used prostate cancer cutoff value of 4.0-10 ng/mL (BPH is a more common cause of elevated PSA levels than is prostate cancer).

  • Serum creatinine: While not recommended by the AUA in the management of patients with BPH, a high serum creatinine value may suggest a bladder outlet obstruction or underlying renal or prerenal disease and an increased risk for post-prostate surgery complications and mortality.


□ Who Should Be Suspected?

  • In adults, the most common symptom of calculi that obstruct the ureter or renal pelvis is excruciating, intermittent pain that radiates from the flank to the groin or to the genital area and inner thigh. The pain is commonly accompanied by urinary urgency, restlessness, hematuria, sweating, nausea, and vomiting.

    • ▼ The waves or paroxysms of pain usually last 20-60 minutes and are related to the passage of the stone down the ureter and the associated ureteral spasm.

    • ▼ Flank pain is caused by upper ureteral or renal pelvic obstruction, whereas genital pain is caused by lower ureteral obstruction.

  • The differential diagnosis of patients with flank pain includes renal bleeding, pyelonephritis, ectopic pregnancy, rupture or torsion of an ovarian cyst, dysmenorrhea, intestinal obstruction, diverticulitis, appendicitis, biliary colic and cholecystitis, and herpes zoster. The intestinal and hepatic causes of flank pain are not accompanied by hematuria nor is a herpes zoster infection (which is usually accompanied by a rash).

    Figure 9-1. Algorithm for diagnosis of renal calculi, as revealed by flank pain, renal colic, hematuria, fever, and urinalysis findings. I, increased; N, normal; PTH, parathyroid hormone; HPT, hyperparathyroidism; HHM, humeral hypercalcemia of malignancy.

    TABLE 9-1. Comparison of Types of Idiopathic Hypercalciuria




    Due to

    Primary hyperparathyroidism

    Primary increase in intestinal absorption; reabsorption autosomal

    Abnormal renal tubular dominant


    Least common

    Most common

    1/10 as common as absorptive type

    2-hour urine after fasting


    30 mg

    <20 mg


    Calcium/creatinine ratio




  • Precipitating causes in adults with calculi (20-30%) include destructive bone diseases (either destructive, e.g., metastatic tumors, or osteoporotic, e.g., immobilization, Paget disease, or Cushing syndrome); milk-alkali (Burnett) syndrome; hypervitaminosis D; sarcoidosis; RTA type I (hypercalciuria, highly alkaline urine, normal serum calcium); hyperthyroidism; and gout (25% of primary cases, 40% of cases with marrow-proliferative disorders).

  • Precipitating causes in children with calculi include infections (13-40%); hypercalciuria (idiopathic but also caused by distal RTA and therapy with furosemide, prednisone, or ACTH); oxaluria (3-13%); uric acid (4%); cystinuria (5-7%); hypocitraturia (10%); xanthine (an inborn error of metabolism); and adenine phosphoribosyltransferase deficiency.

□ Laboratory Findings

  • Two 24-hour urine specimens should be collected and tested for daily volume and levels of magnesium, sodium, uric acid, calcium, citrate, and oxalate.

    • ▼ A urine culture should be performed to detect infecting microorganisms.

    • ▼ Urine microscopy should be performed to detect the presence and level of red cells, white cells, urinary casts, and crystals.

    • ▼ Calculi should be collected by urination through a stone screen, for chemical analysis.

  • Hematuria: Gross or microscopic, occurs in 80% of symptomatic patients and is the single most definitive predictor of a calculus in patients with unilateral flank pain. However, hematuria is not detected in 10-30% of patients with documented nephrolithiasis.

  • Renal function tests: Useful for interpretation of hypercalcemia.

  • Crystalluria: Diagnostically useful for cystine crystals (in familial cystinuria) or struvite crystals.

  • Cyanide-nitroprusside test: Positive (false positive may occur with sulfurcontaining drugs). Calcium oxalate, phosphate, and uric acid should arouse suspicion about possible causes, but they may occur in normal urine.

  • Neutrophilia: Suggestive of infection, for example, in the finding of struvite crystals.


□ Who Should Be Suspected?

  • Hematuria is common and, in many patients, particularly young adults, is transient and inconsequential. With increasing age, common causes can
    include inflammation or infection of the prostate or bladder and calculi. In patients over age 35, hematuria is associated with a higher risk of BPH and renal or GU malignancies.

  • Patients on oral anticoagulants and those with a high international normalized ratio (INR) are at higher risk of hematuria. Even if present in such patients, it is necessary to investigate for alternative source(s) of the condition.

  • Isolated hematuria occurs in patients with calculi, trauma, prostatitis, sickle cell trait or disease, tuberculosis, and Schistosoma haematobium infection. Acute cystitis or urethritis in women can cause gross hematuria. Hypercalciuria and hyperuricosuria are also risk factors for unexplained isolated hematuria.

  • Benign familial or recurrent hematuria refers to asymptomatic, recurrent hematuria without proteinuria or other laboratory abnormalities. Persistent or recurrent hematuria, even if only microscopic, should be investigated, especially in patients over age 50. Other family members may be affected. The condition may clear spontaneously.

□ Laboratory Findings

  • The single most important test in the evaluation of hematuria is the microscopic analysis of urine sediment, which can often distinguish glomerular from nonglomerular bleeding.

  • Microscopy of centrifuged urinary sediment should be examined under high dry magnification. Note that <3% of normal persons have ≥3 RBC per HPF. RBCs or casts indicate that the blood is of glomerular origin. The most common causes of isolated glomerular hematuria are IgA nephropathy, hereditary nephritis (Alport syndrome), and thin basement membrane disease. The presence of clots rules out a glomerular origin—large thick clots suggest a bladder origin, whereas small stringy clots indicate upper urinary tract disease. The presence of WBCs suggests inflammation or infection.

  • The urine dipstick can detect RBCs at a level equivalent to one to two RBCs per HPF but results in more false-positive tests owing to a number of interfering factors (listed below), and so a positive dipstick test must be confirmed by microscopic examination of the urine. Proteinuria is also detected by dipstick, and a 2+ proteinuria in the presence of microscopic hematuria indicates glomerular disease.

  • Immunocytochemical staining for human Tamm-Horsfall protein is positive with >80% of RBCs of renal origin and <13.1% of RBCs of nonrenal origin.

  • Imaging studies, urinary cytology, cystoscopy, or occasionally renal biopsy may be indicated in cases of persistent hematuria with no obvious etiology.

□ Limitations on the Urine Dipstick Test

Mar 20, 2021 | Posted by in PATHOLOGY & LABORATORY MEDICINE | Comments Off on Genitourinary System Disorders

Full access? Get Clinical Tree

Get Clinical Tree app for offline access