One-year follow-up results of patients with prenatally diagnosed hydronephrosis and evaluation of renal functions

Abstract

Introduction: Hydronephrosis is the most common urologic anomaly detected in the fetus. Obstructive uropathy can cause long-term mortality and morbidity by leading to renal damage and decreasing renal functions. Objective: We aimed to determine the etiological reasons and frequency of prenatal determined hydronephrosis, also to evaluate the association between some (clinical and laboratory) parameters and renal functions during study. Patients and method: 48 patients with antenatally detected hydronephrosis were followed prospectively. The ultrasonography scan and renal functioning tests were performed on day 3rd-7th of life and repeated on week 4th-6th, months 3rd, 6th and 12nd. Results: The degree of hydronephrosis at the end of study was decreased significantly when compared to antenatal hydronephrosis severity (p<0.05). Transient hydronephrosis was diagnosed in 22 (28.9%) of 76 renal unit with prenatal hydronephrosis. Ureteropelvic junction obstruction was the most common cause of antenatal hydronephrosis. Positive correlations between the end study glomerular filtration rate (GFR) and tubular reabsorption of phosphate, blood urea nitrogen and creatinine levels were found at the end of the study. Some significant negative correlations between the end study GFR and fractional excretions of K+ and Mg++ were found at several periods of the study. Conclusion: Transient hydronephrosis is one of the most important reasons of prenatally detected hydronephrosis. The patients with antenatal hydronephrosis must be followed-up closely. Tubular functioning test may be impaired in early stages. The episodic evaluation of tubular functions may predict renal damage before the development of renal failure.