LAUSR

The position paper by Malmstrom et al. regarding developing a Nordic standard for investigation of hematuria raises important points regarding the challenges that hematuria evaluation brings to clinicians. The condition is highly prevalent and in the case of microscopic hematuria rarely due to a clinically meaningful cause (cancer, renal failure, infection) [1]. Recommendations for macroscopic hematuria (MaH) are less controversial since cancer is found 10–20% of the time but this is far less common than microscopic hematuria (MiH). As such, there is wide variability in recommendations regarding evaluation of MiH from “no evaluation” in some countries to aggressive evaluation in others like US where asymptomatic MiH in those aged over 35 with no other explained causes leads to recommendation of upper tract imaging and cystoscopy [2]. There are numerous issues that have resulted in the differences in recommendations and most of the blame lies in the absence of randomized trials to support a ‘correct’ approach. One consideration is whether to view this as an individual problem or a population problem. From an individual perspective, the finding of blood in the urine even at a microscopic level is concerning. The rates of cancer in referred populations is 1–5% but this likely represents a bias since most patients with MiH are not referred. From a population perspective, the number of patients with MiH would overwhelm healthcare systems and the low positive predictive value of a one-time finding of MiH does not justify the enormous costs/resources associated with evaluating every patient. What are the directions forward? The Nordic countries have an opportunity to make advancements since they have robust national registries. The Fast Track Approach makes sense to expedite care of higher risk patients like MaH. As noted in this paper, this can increase referral since some providers did not refer these higher risk patients. The harder question is which patients with MiH to refer. Symptoms are not common for bladder cancer early on and hence many have focused on what to do in patients with asymptomatic MiH. However, the use of known risk factors such as age, gender and carcinogen exposure have not been robustly incorporated into recommendations [3]. Using registries to understand the risk factors of those who develop bladder cancer and impact of timing of evaluation on stage of disease could improve recommendations for evaluation. At this time, it is difficult to review the many screening studies and papers evaluating MiH and assure patients that no evaluation is necessary [1]. There is clearly a risk of cancer but the actual rate is challenging to determine due to high rates of patients who do not undergo evaluation [4,5]. There is also retrospective multicenter data that suggests that detection of bladder cancer when patients have MiH results in a lower stage of detection than MaH [6]. As such, there is a potential risk with arbitrarily stopping all evaluation of patients with MiH. Ideally, randomized studies assessing the value of evaluation of MiH and the potential use of risk-stratification to determine intensity of evaluation will help determine the optimal recommendations. In the meantime, use of population-based data can provide further insights into this complicated issue.