Outcomes of renal calculi in patients with spinal cord injury

Patients with spinal cord injury (SCI) are at risk of developing renal calculi. This study describes the management of renal calculi among patients with SCI with attention to factors influencing surgical management vs observation.

This retrospective, cohort study identified patients with SCI and renal calculi between 2009 to 2016 from an institutional neurogenic bladder database and detailed the management of their stones. A stone episode was defined as radiographic evidence of new calculi.

Of 205 patients with SCI, 34 had renal stones, for a prevalence of 17%. The mean age was 50 years (range 22,77) and most had cervical SCI (n = 22, 65%). There were 41 stone episodes with 98 individual stones identified with a mean stone size of 4.9 mm (range 1-19). Of the 41 episodes, 10 (24%) underwent surgery after initial diagnosis. Pain was the most common primary indication for surgery (n = 9, 60%). The median time from diagnosis to intervention for all patients was 4 months (interquartile range 1,23). Of the 41 episodes, 31 (76%) were initially observed and among these, 5 ultimately required surgery (16%) while 26 (84%) did not. Of these 26, 12 (46%) stones passed spontaneously and 14 (53%) remained unchanged. The need for surgery correlated with more stone episodes (P = .049).

In this cohort of patients with SCI and small, nonobstructing renal stones, 76% (n = 31) were offered observation. Of these observed patients, 84% (n = 26) did not require further intervention at a median of 4 years of follow-up.