Most experts agree that a complete urologic evalua-tion should include imaging of the upper urinary tract and cytoscopic examination of the urinary bladder.. The goal of imaging is to de
Trang 1Most experts agree that a complete urologic
evalua-tion should include imaging of the upper urinary
tract and cytoscopic examination of the urinary
bladder The role of urine cytology is controversial,
as a negative cytology can never completely exclude
the presence of a bladder tumor[12] The goal of
imaging is to detect neoplasms, including renal
cell carcinoma (RCC), and the less prevalent
transi-tional cell carcinoma (TCC), of the renal pelvis and
ureters, urinary tract calculi, renal cystic disease, and
obstructive lesions[11]
This article discusses the current status of imaging
of patients suspected of having urologic causes of
hematuria The imaging of posttraumatic
hematu-ria, of patients with UTI, and patients with
glomer-ular causes of hematuria is beyond the scope of this
review The role of all modalities, including plain
radiography, intravenous urography or excretory
ur-ography, retrograde pyelur-ography, ultrasonur-ography,
multidetector computed tomography (MDCT),
including MDCT urography (MDCTU) and
mag-netic resonance (MR) urography, is discussed In
recent years, MDCTU has undergone significant
development and has been the subject of research
and investigation as a new technique for evaluation
of patients with urinary tract pathology [13,14]
Evidence is accumulating, which suggests that this
technique is now ready to play a pivotal role in
im-aging of patients presenting with hematuria This
article highlights the current status of MDCTU in
imaging of patients with hematuria, and discusses
various—often controversial—issues, such as
opti-mal protocol design, accuracy of the technique in
imaging of the urothelium, and the significant issue
of radiation dose associated with MDCTU
Common urologic causes of hematuria
Urinary tract calculi
Urolithiasis is associated with idiopathic
hypercal-ciuria, secondary hypercalhypercal-ciuria, and
hyperuricosu-ria[15] Stones are most commonly composed of
calcium oxalate and phosphate (34%), calcium
oxalate (33%), calcium phosphate (6%), mixed
struvite and apatite (15%), uric acid (8%), and
cys-tine (3%)[3] Nephrocalcinosis is characterized by
the formation of calculi within renal tubules and
interstitium, leading to impaired renal function
[16] Nephrocalcinosis is associated with medullary
sponge kidney, renal tubular acidosis, and
hyper-parathyroidism, and may present with hematuria
[16,17] Urinary tract calculi frequently present
with ureteric colic caused by obstruction of the
uri-nary collecting system With regard to the
associa-tion of urinary tract calculi with development of
microscopic hematuria, a recent study by Edwards
and colleagues[6]showed a prevalence of urinary
tract calculi of 7.8% in adult patients with micro-scopic hematuria and 8.8% in patients with macro-scopic hematuria
Malignancy The most common malignant conditions associ-ated with hematuria in adults are renal cell carcinoma, transitional cell carcinoma, prostate carcinoma, and less commonly, squamous cell car-cinoma, which can result from chronic inflamma-tory conditions[18–20]
RCC is the most common malignant neoplasm of the kidney, representing up to 90% of renal neo-plasms and up to 3% of all neoneo-plasms [18,21] RCC is more common in men than women, has
a peak incidence at 60 to 70 years of age, and is asso-ciated with smoking, obesity, and antihypertensive therapy[22] In recent years, the triad of flank pain, hematuria, and a palpable mass is less frequently the mode of presentation for RCC, because over 50% of lesions are identified by cross-sectional imag-ing, either incidentally or when performed for vague and apparently unrelated symptoms This is not sur-prising, as systemic symptoms, such as anorexia and weight loss, are commonly associated with RCC[23] Urothelial tumors account for 10% of upper uri-nary tract neoplasms [24] Although urothelial malignancies are most likely to occur in the blad-der, the ureters have been reported to be involved
in 2%, and the renal pelvis (extrarenal pelvis in preference to infundibulocalyceal regions) in 5%
of cases[19,25] The multifocal and bilateral nature
of TCC makes this a challenging condition for the radiologist[23] Synchronous tumors occur in up
to 2% of renal and 9% of ureteric lesions, with metachronous lesions typically occurring within the bladder in up to 50% of cases with upper ure-teric tumors on presentation [26,27] Therefore, imaging is required for primary diagnosis of TCC but is also very commonly used for detection of synchronous and metachronous lesions[23] Bladder neoplasia is the fifth most common ma-lignancy in Europe and the fourth most common cancer in the United States[28] TCC of the bladder occurs more commonly in men than women, is associated with smoking (fourfold greater than in nonsmokers), exposure to chemicals such as ben-zene and 2-naphtylamine, and structural abnormal-ities (horseshoe kidney) [29,30] Squamous cell carcinoma and adenocarcinoma are significantly less common in the bladder than TCC[31] Greater than 70% of bladder cancers are superficial and 25% invade muscle at the time of diagnosis[32] Bladder cancer most frequently presents with hematuria but can be associated with more nonspe-cific signs, such as urinary frequency and urgency, dysuria, and suprapubic pain[23]
O’Connor et al
114