Non-visible hematuria, also referred to as 'microscopic hematuria' or 'dipstick positive hematuria' is a common reason for urology referrals with prevalence rates that range from 13% to 20%. The main concern for investigating non-visible hematuria, especially in the absence of lower urinary tract symptoms, is its potential relation to urinary tract malignancy, which however does not exceed 5%. The pathway of investigation of non-visible hematuria is impeded by the lack of clarity over definitions, diagnosis and specialist referral criteria. Towards that goal guidelines have been introduced by different societies. In this review we aim to discuss differences in current guideline regarding the investigation, management and follow up of non-visible hematuria. Areas covered: Guidelines, recommendations, algorithms and original articles on hematuria published in the English literature were retrieved using the following PubMed search terms 'microscopic hematuria', 'dipstick hematuria', 'non-visible hematuria' and 'guidelines'. Expert commentary: Available guidelines for investigation of microscopic hematuria actually differ both in the extent and the intensity of the proposed imaging and invasive tests. There is evidence that guidelines are not adhered to and this reflects the necessity for introducing selection criteria and maybe variable levels of investigation for microscopic hematuria depending on the individual patient.
Keywords: Non-visible asymptomatic hematuria; bladder cancer; computed tomography; cystoscopy; guidelines.