Microhematuria: AUA/SUFU Guideline

Patients presenting with microhematuria represent a heterogeneous population with a broad spectrum of risk for genitourinary malignancy. Recognizing that patient-specific characteristics modify the risk of underlying malignant etiologies, this guideline sought to provide a personalized diagnostic testing strategy.

The systematic review incorporated evidence published from January 2010 through February 2019, with an updated literature search to include studies published up to December 2019. Evidence-based statements were developed by the expert Panel, with statement type linked to evidence strength, level of certainty, and the Panel's judgment regarding the balance between benefits and risks/burdens.

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.

Patients with microhematuria should be classified based on their risk of genitourinary malignancy and evaluated with a risk-based strategy. Future high-quality studies are required to improve the care of these patients.