In this study, we observed a significant reluctance amongst primary care physicians in a universal health care system to refer patients with gross or significant microscopic hematuria to urology for further investigation.
There is consensus amongst experts that gross hematuria is a worrisome presentation and warrants a thorough investigation.
3,7–10 This certitude stems from strong evidence associating it with urologic malignancies. In fact, visible blood in the urine is thought to be the first presentation in 85% and 40% of patients with bladder and renal cancers, respectively.
8 As such, in this setting, both the CUA and AUA recommend thorough physical examination, upper tract imaging with computerized tomography (CT), intravenous urography (IVU) or renal ultrasound, as well cytology and cystoscopic examination.
3,4With that in mind, our first goal was to investigate how GPs would approach a patient with macroscopic hematuria and presented the case of a 45-year-old man with resolved asymptomatic gross hematuria and no evidence of infection. We were surprised to see that only 63.7% of the respondents elected to refer to urology for full investigation. Notably, this rate is similar to ones obtained from another recent large multi-institutional questionnaire emanating from the United States with only 69% and 77% of physicians from 2 different centres electing to refer to urology in the face of gross hematuria.
11 As such, one conclusion that could be extracted from this is that there seems to be a generally relaxed attitude and/or lack of knowledge with regards to referring and fully evaluating patients with gross hematuria. Another potential explanation could be the difficult access to specialists in Quebec, thus discouraging GPs from referring to urology. This approach is concerning and may possibly lead to delays in diagnosis and initiation of therapy for potentially serious conditions.
We then chose to shift our attention to the more common scenario of asymptomatic microscopic hematuria and its management. The challenge here is to detect the more serious conditions while minimizing the costs and morbidity of unnecessary investigation. This is particularly true when one keeps in mind that in retrospective studies, an overall prevalence rate for microscopic hematuria as high as 13% in the general population has been reported.
12 As such, while there is a need for risk stratification to appropriately detect worrisome patients, there still remains an elevated chance of malignancy with microscopic hematuria. Referral studies have shown that up to 26% of high-risk patients with hematuria harbour genitourinary malignancies.
13 Even in low-risk cases, 4% of patients with asymptomatic microscopic hematuria are found to have bladder cancer.
14 The need for early detection in these patients is further illustrated by the fact that 92% of cancers detected during the workup of hematuria are still localized and curable.
15 Accordingly, best practice guidelines were put forth by the European Association of Urology, CUA and the AUA. In the absence of external factors or evidence of glomerular source, the AUA guidelines recommend upper tract imaging, cystoscopy and cytology in all adult patients.
5 The CUA has slightly varied guidelines with immediate urine cytology collection and cystoscopy alongside initial upper tract imaging (renal ultrasound) in all patients over 40 years old or if risk factors are present regardless of the patient’s age.
3To evaluate GP practice patterns in this population of patients with significant microscopic hematuria and to assess any gender disparity among GP evaluation, we presented a clinical scenario of a postmenopausal woman with 2 episodes of clear asymptomatic microscopic hematuria. We were also surprised to see that only 48.6% of GPs elected for referral to urology for further investigation. These results, though low, were still an improvement over the referral rates in the previously reported American-based questionnaire (36% referral to urology for microscopic hematuria).
11 One may argue that the reluctance to refer to urology may stem from lack of knowledge about the association between hematuria and genitourinary malignancy at the primary care level; however, this is not the case in this study as >90% of respondents stated that microscopic hematuria was associated with bladder cancer. The disparity between the referral rates within the 2 above-mentioned clinical scenarios may be due to multiple factors. For example, the level of suspicion may be higher when evaluating patients with gross hematuria compared to microscopic hematuria; similarly, the level of suspicion of serious urologic conditions may also be higher at the primary care level when evaluating male versus female patients who present with hematuria. This finding is supported by several studies showing significant delay in diagnosis and workup in females who present with hematuria when compared to male.
6Another possibility for this reluctance to refer or workup microscopic hematuria seems to be related to how GPs define and quantify
significant microscopic hematuria. Whether one opts to follow the AUA or CUA guidelines, most would agree that the upper limit of normal for the presence of RBC in urine is 2 RBC/HPF.
3,4 Also, emphasis is placed on the fact that there is no safe value for microscopic hematuria to safely rule out transitional cell carcinoma.
16 Our survey showed that over half of the GPs considered ≥10 RBC/hpf to be significant with only 42.1% correctly answering ≥3 RBC/ hpf. Clearly, the need for hematuria education seems to extend to basic concepts which are essential for accurate diagnosis and treatment.
Finally, we asked the physicians who they would consider screening with a urinalysis on a routine physical check-up. Around half of the respondents perform routine screening urinalysis on all men and women regardless of risk factors (such as smoking history or occupation exposure to chemicals). This was surprising since the American Cancer Society, the AUA and the CUA do not currently recommend routine screening urinalysis. Furthermore, the US Preventive Services Task Force and the Canadian Task Force on the Periodic Health Examination both recommend
against doing so in the face of insufficient evidence.
3,4,17–19We believe this project to be a very helpful tool in the assessment of general practice with regards to diagnosis, workup and management of a very common urologic presentation, such as hematuria. Clearly, further education needs to be implemented at the primary care level to correct deficiencies, prevent delays in diagnosis, and improve care.