Percutaneous Nephrolithotomy and Spina Bifida - Complex Major Stone Surgery?

Background The incidence of spina bifida (SB) is approx 1:1000, and risk of stone disease is substantially raised in SB. This is the unique published study of the outcome of patients with SB undergoing percutaneous nephrolithotomy (PCNL) compared to a neurologically intact historically matched control group at the same institution. Patients and Method A series of 96 PCNLs in 13 SB and 50 non-SB control patients was analysed. The following measurements were recorded: (1) Co-morbidities; (2) Pre-operative: (renal function, American Society of Anesthesiologists (ASA) score); (3) Intra-operative: (anaesthesia time, number of tracks, stone free rate) and (4) Post-operative: (sepsis, intensive therapy unit (ITU) and total length of stay, transfusion rate, stone composition, rate of stone disease-related nephrectomy). Results Retrograde access to the ureter was impossible in all cases of SB. The median ASA grade (OR 10.5, 95% C.I. 2.6 to 42.7) and operative time (median difference 30mins, 95% C.I. 20 to 40) were both higher in the SB cohort. Surgeon's estimate of stone free rate was significantly lower in the SB cohort (46% versus 82%). Intensive care requirement (0.29 days / PCNL versus 0.1 days / PCNL); total hospital stay (7 versus 4 days); post operative transfusion rate (11.8% versus 1.6%) and sepsis rate (38% versus 1.6%) were all significantly higher in the SB group. Repeat PCNL, and nephrectomy for recurrent stone disease were both significantly increased in SB cohort compared to control group. Conclusions PCNL in patients with SB is associated with multiple parameters of poor outcome. Patients with SB should be counselled about increased peri-operative risk and likelihood of stone recurrence. In an era where hospitals are judged according to comparative outcomes, a case may be made for comparing PCNL in this cohort of patients separately because of the significantly increased peri- and post-operative morbidity.