Response to Hamilton et al. re: Conservative Management of Staghorn Calculi: When Is It Safe?

Background: To describe the clinical characteristics, infectious and kidney function patterns, and overall outcomes in a cohort of patients with staghorn calculi treated conservatively. Methods: Staghorn calculi treated nonoperatively between January 2009 and January 2017 were identified. A retrospective analysis was completed. Results: Twenty-nine patients were identified with a median age of 74 years (interquartile range [IQR] 61-81). Mean follow-up was 24 months. Fifty-nine percent (17/29) had complete staghorn calculi with 6/29 (21%) bilateral. Mean body mass index was 29.4 (IQR 24.8-31.7). Of the 29 patients, 14 were treated conservatively due to comorbidities, 12 refused treatments, and 3 were due to aberrant anatomy. The age-adjusted Charlson Comorbidity Index (CCI) score demonstrated 8 patients in our cohort with a CCI of <3, 11 patients with a CCI of 4 or 5, 7 patients with a CCI of 6 or 7, and 3 patients with a CCI of >8. Overall, kidney function remained stable for 19/29 patients (66%) and the glomerular filtration rate decreased by <10% for 4/29 (14%), by 10%-29% for 2/29 (7%), and >30% for 4/29 patients (14%) over the study period. None of the study patients required hemodialysis. No patients in the cohort developed an abscess, nor were any patients on daily prophylactic antibiotics. There was only one related admission for a complication during the study; this was for pyelonephritis. There were two deaths during the study period. One death was an unrelated cardiac death and the other was from urosepsis; this patient had been noncompliant with follow-up. Conclusions: Outcomes for patients treated conservatively were reasonable in this select group. There is a need for future prospective studies to show whether conservative treatment of these patients is safe.