Increased kidney stone risk following total pancreatectomy with islet autotransplantation.

Background/objectives: Chronic pancreatitis (CP) is associated with increased risk of calcium-oxalate kidney stones, likely due to enteric hyperoxaluria. However, the risk of kidney stones for patients with CP after total pancreatectomy with islet autotransplantation (TPIAT) is unknown. We aimed to evaluate kidney stone risk in patients with CP after TPIAT.

Methods: A retrospective analysis of 629 patients who underwent TPIAT was conducted to identify patients who developed kidney stones post-TPIAT. Kaplan-Meier analysis estimated time to first event. An Anderson-Gill proportional-hazards analysis of all kidney stone events described key clinical associations.

Results: Mean age at TPIAT was 33 years (SD 15.3, range 3-69); 69.8 % (n = 439) were female. The estimated chance of any kidney stone episodes by 5 years post-TPIAT was 12.8 % (95 % CI: 8.8-16.6 %); by 10 years, 23.2 % (CI: 17.5-28.6 %); by 15 years, 29.4 % (CI: 21.8-36.2 %). Significant associations with kidney stones post-TPIAT included older age (HR 1.25 per 10 years), smoking history (HR 1.72), mild chronic kidney disease (HR 1.96), renal cysts (HR 3.67), pre-TPIAT kidney stones (HR 4.06), family history of kidney stones (HR 4.10), and Roux-en-Y reconstruction (HR 2.68). Of the 77 patients who developed kidney stones, 34 (44.1 %) had recurrent episodes. Of 143 total kidney stone events, 35 (24.5 %) required stone removal, 79 (55.2 %) resolved spontaneously, and 29 (20.3 %) were missing this data.

Conclusions: Patients with CP post-TPIAT commonly have kidney stones: nearly 3 in 10 have ≥1 kidney stone episodes within 15 years. Clinicians should be aware of this risk and counsel patients on prevention.