Predictive value of urinary Tamm-Horsfall protein and 24-hour urine osmolality for recurrence in patients with calcium oxalate stones

Introduction: To investigate the predictive value of urinary Tamm-Horsfall protein (THP) and 24-h urine osmolality for recurrence in patients with calcium oxalate (CaOx) stones. Methods: : The clinical data of 120 patients hospitalized for upper urinary tract stones between January 2020 and January 2022 in our hospital were retrospectively reviewed. Patients with and without stone recurrence at postoperative follow-up were divided into a recurrence group (53 patients) and a non-recurrence group (67 patients); 50 healthy patients during the same period were selected as the control group. Levels of urinary THP, 24-h urine osmolality, and biochemical indices were then compared between the three groups. Receiver operating characteristic (ROC) curves were applied to predict the predictive values of urinary THP and 24-h urine osmolality for stone recurrence. Results: : Urinary THP, 24-hour urine osmolality, and biochemical indices in the recurrence group were significantly higher than those in the non-recurrence group and the control group (P < 0.05). 24-h urine osmolality was positively correlated with urinary oxalic acid and calcium excretion. ROC curve analysis showed that the optimal cut-off values for urinary THP and 24-h urine osmolality for the prediction of stone development were ≥27.01mg/L and ≥577.69mOsm/(kg·H 2 O); furthermore, the combination of these indices significantly improved the accuracy of prediction. Conclusion: Urinary THP and 24-hour urine osmolality are higher in patients with recurrent CaOx stones; the combined detection of these parameters can accurately predict stone recurrence.