Elliot K. Fishman M.D.
Johns Hopkins Hospital

Click here to view this module as a video lecture.

“Hematuria is defined as the presence of red blood cells in the urine. When visible to the patient, it is termed gross hematuria and is usually alarming to patients. Microscopic hematuria is that detected by the dipstick method or microscopic examination of the urinary sediment.”
American Urologic Association

“Macroscopic haematuria is a commonly seen condition in the emergency department (ED), which has a variety of causes. However, most importantly, macroscopic haematuria has a high diagnostic yield for urological malignancy. 30% of patients presenting with painless haematuria are found to have a malignancy. The majority of these patients can be managed in the outpatient setting.”
Management of macroscopic haematuria in the emergency department
Hicks D, Li CY
Emerg Med J. 2007 Jun; 24(6): 385–390.

“In men aged >60 years, the positive predictive value of macroscopic haematuria for urological malignancy is 22.1%, and in women of the same age it is 8.3%. In terms of the need for follow‐up investigation, a single episode of haematuria is equally important as recurrent episodes.”
Management of macroscopic haematuria in the emergency department
Hicks D, Li CY
Emerg Med J. 2007 Jun; 24(6): 385–390.

Urinary tract malignancy: kidney, renal pelvis, ureter, bladder, prostate, urethra

• Urinary calculi
• Infections: urinary tract infection, schistosomiasis
• Trauma: penetrating or blunt
• Benign prostatic hyperplasia
• Haemorrhagic cystitis
• Endometriosis
• Nephrological disease: IgA nephropathy, glomerulonephritis
• Postprocedural bleeding—for example, transurethral surgery
• Bleeding disorders, anticoagulation therapy above therapeutic range
• Arteriovenous malformation/angiomyolipoma

Microhematuria should be defined as ≥3 red blood cells per high power field on microscopic evaluation of a single specimen. In patients diagnosed with gynecologic or non-malignant genitourinary sources of microhematuria, clinicians should repeat urinalysis following resolution of the gynecologic or non-malignant genitourinary cause. The Panel created a risk classification system for patients with microhematuria, stratified as low-, intermediate-, or high-risk for genitourinary malignancy. Risk groups were based on factors including age, sex, smoking and other urothelial cancer risk factors, degree and persistence of microhematuria, as well as prior gross hematuria. Diagnostic evaluation with cystoscopy and upper tract imaging was recommended according to patient risk and involving shared decision-making. Statements also inform follow-up after a negative microhematuria evaluation.
Microhematuria: AUA/SUFU Guideline 
Daniel A. Barocas et al.
J Urol 2020 Oct;204(4):778-786.

”At the same time, practice-pattern assessments have demonstrated significant deficiencies in the evaluation of patients presenting with hematuria. For example, one study found that less than 50% of patients with hematuria diagnosed in a primary care setting were subsequently referred for urologic evaluation. Furthermore, performance of both cystoscopy and imaging occurs in less than 20% of patients in most series, and varies to some degree by sex and race. The underuse of cystoscopy, and the tendency to rely solely on imaging for evaluation, is particularly concerning since the vast majority of cancers diagnosed among persons with hematuria are bladder cancers, optimally detected with cystoscopy.”
Microhematuria: AUA/SUFU Guideline 
Daniel A. Barocas et al.
J Urol 2020 Oct;204(4):778-786.

Clinicians should perform cystoscopy and axial upper tract imaging in patients with MH categorized as high-risk for malignancy. (Strong Recommendation; Evidence Level: Grade C) Options for Upper Tract Imaging in High-Risk Patients:

• a. If there are no contraindications to its use, clinicians should perform multiphasic CT urography (including imaging of the urothelium). (Moderate Recommendation; Evidence Level: Grade C)
• b. If there are contraindications to multiphasic CT urography, clinicians may utilize MR urography. (Moderate Recommendation; Evidence Level: Grade C)
• c. If there are contraindications to multiphasic CT urography and MR urography, clinicians may utilize retrograde pyelography in conjunction with non-contrast axial imaging or renal ultrasound. (Expert Opinion)

“ The most common diagnoses were renal colic (119/584, 20.4%) and intestinal obstruction (80/584, 13.7%). CT altered the leading diagnosis in 49% of the patients (284/584) and increased mean physician diagnostic certainty from 70.5% to 92.2%. The management plan was changed by CT in 42% (244/583). Surgery was planned for 79 patients before CT, whereas hospital discharge was planned for 25.3% of these patients (20/79) after CT.”
Abdominopelvic CT Increases Diagnostic Certainty and Guides Management Decisions: A Prospective Investigation of 584 Patients in a Large Academic Center
Abujudeh HH, Thrall JH et al
AJR 2011; 196:238-243

“The worldwide prevalence and incidence of urolithiasis have been increasing, with the number of new cases having nearly doubled in the United States over the past 3 decades. Acute urolithiasis is diagnosed in about 1% of all yearly ambulatory care visits in both U.S. and European emergency departments.”
Can Unenhanced CT Findings Predict Interventional Versus Conservative Treatment in Acute Renal Colic? 
Lotan E et al. 
AJR 2016; 207:1016–1021

“The lifetime risk for a urinary calculus disease is 12% for men and 6% for womenRisk factors include a personal or family history of stones, urinary tract anatomic abnormality, obesity, and metabolic disorders. The incidence for stone disease is highest in warm regions and during the summer months because of an increased rate of dehydration.”
Acute Urinary Tract Disorders 
Goel RH, Unnikrishnan R, Remer EM
Radiol Clin N Am 53 (2015) 1273–1292

• Presence or absence of calculus
• Location of calculus (kidney, ureter, bladder)
• Number of stones
• Stone diameter
• Presence of additional findings (i.e. acute pyelonephritis)

Nephrolithiasis: What Surgeons Need to Know
Eisner BH et al.
AJR 2011; 196:1274-1278

“ Not only does this study enable the detection of stones of all sizes, but in its area of examination from above the kidneys to below the bladder base, it enables the evaluation of other urinary and extraurinary abnormalities that may be contributing to symptoms of acute flank pain.”
Nephrolithiasis: What Surgeons Need to Know
Eisner BH et al.
AJR 2011; 196:1274-1278

“ The American Urological Association and the American College of Radiology (ACR) recommend low-dose (for body mass index [BMI] <30) noncontrast CT for the initial presentation of flank pain.”
Acute Urinary Tract Disorders 
Goel RH, Unnikrishnan R, Remer EM
Radiol Clin N Am 53 (2015) 1273–1292

Acute Urinary Tract Disorders 
Goel RH, Unnikrishnan R, Remer EM
Radiol Clin N Am 53 (2015) 1273–1292

Passage of a ureteral calculus depends on size and location, with a spontaneous passage rate of 48% for proximal versus 75% for distal ureteral calculi and 76%, 60%, 48%, and 25% for 2 to 4, 5 to 7, 7 to 9, and greater than 9 mm diameter, respectively.
Acute Urinary Tract Disorders 
Goel RH, Unnikrishnan R, Remer EM
Radiol Clin N Am 53 (2015) 1273–1292

“ROC curves that were constructed for stone size and attenuation revealed that stones larger than 6.5 mm and stones with an attenuation value greater than 1100 HU were more likely to require interventional treatment, with an AUC of 0.74 and 0.68, respectively.”
Can Unenhanced CT Findings Predict Interventional Versus Conservative Treatment in Acute Renal Colic? 
Lotan E et al. 
AJR 2016; 207:1016–1021

“Our results showed that larger stone size, higher density, and proximal location are significantly associated with the selection of interventional over conservative management for patients with acute renal colic. Complaints of shivering, fever, and leukocytosis also strongly correlate with the selection for interventional treatment. Other clinical and radiologic information may be useful as supportive findings, but they were not predictive for the purposes of choosing suitable patient management.”
Can Unenhanced CT Findings Predict Interventional Versus Conservative Treatment in Acute Renal Colic?
Lotan E et al. 
AJR 2016; 207:1016–1021