Relationship between microscopic haematuria and hydronephrosis in urolithiasis

Abstract

The aim of this study was to investigate the relationship between the degree of hydronephrosis and the presence of microscopic haematuria in patients who presented to the emergency department (ED) with ureteral stones. The records of patients who presented to our ED due to urolithiasis between January 2017 and December 2020 were retrospectively analysed. Patients aged 18years or older who underwent non-contrast computed tomography (CT abdomen/pelvis) and urinalysis (UA) and were diagnosed with ureteral stones were included in the study. Radiology reports were reviewed for stone size, localisation and degree of hydronephrosis. Patients with and without microscopic haematuria and the degree of hydronephrosis were compared. A total of 476 patients were included, which consisted of 391 with microscopic haematuria and 85 without microscopic haematuria. The median stone size was 4.1mm in the presence of microscopic haematuria and 5.5mm in the absence of microscopic haematuria. Logistic regression analysis was performed to determine the factors associated with the development of hydronephrosis. Stone size [odds ratio (OR):2.15, 95% confidence interval (CI):1.12-4.16, P<.001), presence of pyuria (OR: 2.58, 95% CI: 1.78-3.48, P<.001) and absence of microscopic haematuria (OR: 1.31, 95% CI 1.04-2.89, P=.017) were identified as risk factors for moderate and severe hydronephrosis. We consider that imaging studies may be necessary for the diagnosis, and treatment of emergency cases in which microscopic haematuria is not detected in urinalysis since their stone size may be larger and degree of hydronephrosis may be more severe.