Value of neutrophil-to-lymphocyte ratio in predicting surgical intervention for hydronephrosis during pregnancy

Background: We aimed to examine the hematological parameters of pregnant patients with ureteral stones that require intervention. Methods: Medical data of patients presenting to urology department between October 2018 and December 2020 were retrospectively analyzed. Patients with flank pain associated with hydronephrosis were included in the study and divided into two groups according to whether an intervention was performed or not (Group-1, Group-2). Ureterorenoscopy (URS) or ureteral stent placement was performed as intervention. Demographic data, complete blood count (CBC), urine analysis, and ultrasonographic findings were collected. Gestational age (week), number of pregnancies, maternal age (years), Anteroposterior pelvis diameter (mm), VAS (Visual Analog Scale) (range 1-10) and mean platelet volume (MPV) were collected from the patient file. Inflammatory markers including neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were computed. Results: About 35 patients were included in Group-1 and 52 patients in Group-2. Ureterorenoscopy was performed in 21/35 (60%) patients, and ureteral stents were placed in 14/35 (40%) patients. None of the patients experienced complications. There was no statistical difference between these two groups in terms of maternal age, gestational age, number of pregnancies, pelvis diameter, PLR, and MPV. VAS and NLR were statistically higher in group-1 (p < 0.05). According to the Receiver operating characteristic curve analysis performed for the prediction of ureteral stone presence, the best cut-off point for the NLR 4.153 (sensitivity 80%, specificity 80.6%, area under curve (AUC): 0.824). Conclusions: We think that NLR can be used to determine the group that needs to be intervented due to ureteral stones in patients with symptomatic hydronephrosis during pregnancy.