Clinical Trial: Nephrolithiasis and Bariatric Surgery

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Nephrolithiasis and Bariatric Surgery

Brief Summary: Test the hypothesis that the new bariatric surgical procedures (BSP) increase stone risk, and will result in an increased incidence and prevalence of stone disease; the purpose is to determine if BSP patients require special management for stone prevention. This study does not include the bariatric surgery but enrolls subjects who are already scheduled for surgery with an affiliated surgeon. The study procedure is to collect 24 hour urines pre-and post surgically to evaluate the risk of kidney stone procedure after surgery.

Detailed Summary:

Surgical therapy for the morbidly obese began when the jejunocolic anastomosis procedure was performed in 1956 but was modified to a jejunoileal technique years later after intolerable metabolic complications ensued.1, 2 In 1969, Payne recommended that the end to side jejunal-ileal bypass (JIB) procedure which preserved 37cm of jejunum and 10cm of ileum should replace the jejunocolic bypass.2 In 1970, Scott modified JIB by increasing the length of intestine used and by fashioning an end-to-end anastomosis between the jejunum and ileum3; this modified procedure soon became the preferred procedure for weight reduction. This foray into bariatric surgery was quickly embraced and JIB was widely adopted. However, in the mid to late 1970's, about 10 years after the first JIB was performed, concern developed regarding the long-term adverse effects of anemia, vitamin deficiencies, nephrolithiasis and ultimately even renal and liver failure.4-14 It was not until a number of patients had end organ failure that the full impact of the complications of JIB were recognized. Much of the complications stem from the malabsorptive component that results from JIB. As fat is malabsorbed, fat-soluble vitamins and calcium are saponified. Subsequently, nutrients are lost and an increased oxalate load is delivered to the large intestine as the calcium that would normally bind oxalate is lost with the malabsorbed fat. In addition, bile salts normally reabsorbed in the ileum are delivered to the colon, increasing the permeability of the colonic mucosa to oxalate. These factors result in increased uptake of oxalate in the large intestine. Oxalate, which cannot be metabolized by humans, is rapidly cleared by the kidney resulting in "intestinal" hyperoxaluria and calcium oxalate nephrolithiasis4-6, 12, 15 and nephrotoxicity.7, 10, 11, 13, 16 The probability of a severe renal complication after JIB was calculated to be about 21% at 5 years a
Sponsor: Indiana Kidney Stone Institute

Current Primary Outcome: To quantify the prevalence of stone disease among patients at the Clarian Hospitals who have had BSP between 3 and 3.5 years previously. [ Time Frame: In the next two years ]

Original Primary Outcome: To quantify the prevalence of stone disease among patients at the Clarian Hospitals who have had BSP between 3 and 3.5 years previously.

Current Secondary Outcome: To identify clinical and laboratory risk factors for incident nephrolithiasis following bariatric surgery. [ Time Frame: In the next two years ]

Original Secondary Outcome: To identify clinical and laboratory risk factors for incident nephrolithiasis following bariatric surgery.

Information By: Indiana Kidney Stone Institute

Dates:
Date Received: September 9, 2005
Date Started: August 2005
Date Completion:
Last Updated: March 4, 2014
Last Verified: March 2014