Percutaneous Nephrolithotomy and Spina Bifida: Complex Major Stone Surgery?

The incidence of spina bifida (SB) is ∼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.

A series of 96 PCNLs in 13 SB and 50 non-SB patients was analyzed. The following measurements were recorded: (1) Comorbidities; (2) Preoperative: (renal function, American Society of Anesthesiologists [ASA] score); (3) Intraoperative: (anesthesia time, number of tracks, stone-free rate); and (4) Postoperative: (sepsis, intensive therapy unit and total length of stay, transfusion rate, stone composition, rate of stone disease-related nephrectomy).

Retrograde access to the ureter was impossible in all cases of SB. The median ASA grade (OR 10.5, 95% confidence interval [CI] 2.6-42.7) and operative time (median difference 30 minutes, 95% CI 20-40) were both higher in the SB cohort. Surgeon's estimate of stone-free rate was significantly lower in the SB cohort (46% vs 82%). Intensive care requirement (0.29 days/PCNL vs 0.1 days/PCNL); total hospital stay (7 days vs 4 days); postoperative transfusion rate (11.8% vs 1.6%); and sepsis rate (38% vs 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.

PCNL in patients with SB is associated with multiple parameters of poor outcome. Patients with SB should be counseled 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 postoperative morbidity.