Oral Calcium Supplementation, a Strategy to Reduce Kidney Stones in Crohn's Patients Living With a Small Bowel Resection

Calcium Supplements Strategy for Kidney Stones Prevention in Crohn's Patients


Lead sponsor: University of British Columbia

Collaborator: University of Texas Southwestern Medical Center

Source University of British Columbia
Brief Summary

Hospitalization for kidney stones in the Inflammatory Bowel Disease (IBD) population is common, particularly among Crohn's patients who had a small bowel resection. This patient population experiences a lifetime occurrence of kidney stone formation as high as 25% accompanied with a high rate of recurrence (the typical rate of stone formation is ~10% in the non IBD population). Giving oral calcium is used to bind oxalate in the intestine in an attempt to reduce the amount of oxalate that is absorbed into the body and to reduce urinary oxalate levels. However, there are no defined guidelines for the optimum dosing of calcium. This study's primary objective is to scientifically define an appropriate range of calcium supplementation that reduce the level of oxalate found in the urine of patients living with inflammatory bowel disease.

Detailed Description

The primary objective of this study is to establish optimal oral calcium supplementation in Crohn's patients who have had an ileal bowel resection. This population is at high risk for calcium oxalate kidney stones, a direct consequence of extensive gut malabsorption and enteric hyperoxaluria. The benefit of providing oral calcium in this patient population (as a means to reduce intestinal oxalate absorption) is known, however, there are no appropriate targets for calcium dosing, which is presently performed empirically or not at all. Our goal is to establish simple, safe and practical guidelines for calcium supplementation.

Overall Status Recruiting
Start Date December 2012
Completion Date December 2020
Primary Completion Date December 2020
Phase N/A
Study Type Interventional
Primary Outcome
Measure Time Frame
Molar ratio of urinary calcium:oxalate in relation to the supersaturation product of calcium oxalate 7 days
Secondary Outcome
Measure Time Frame
Optimal level of Ca supplementation for prevention of stones in Crohn's patients 7 days
Enrollment 40

Intervention type: Dietary Supplement

Intervention name: Calcium Carbonate

Description: There is a regimen for dietary supplement intake that will be provided to study participants.

Arm group label: Dietary supplement

Other name: CaCO3



Inclusion Criteria:

1. a pathologically confirmed diagnosis of Crohn's disease

2. prior ileal resection with an intact colon (surgery>6 months preceding involvement in study)

3. hyperoxaluria (defined as> 48 mg (>0.5 mmol) per 24 hour urine samples.

- Patients will not be excluded if they are known kidney stone formers.

Exclusion Criteria:

1. current pregnancy

2. patient's without baseline hyperoxaluria (defined as >48 mg or 0.5mmol per 24 hour urine samples)

3. patients in renal failure assessed by a GFR < 60

4. inability to provide informed consent

5. active cancer

6. hyperparathyroidism

7. hyperphosphatemia

8. <19 years of age

Gender: All

Minimum age: 19 Years

Maximum age: N/A

Healthy volunteers: No

Overall Official
Last Name Role Affiliation
Ben Chew, MD Principal Investigator University of British Columbia
Overall Contact

Last name: Olga Arsovska

Phone: 6048754111

Phone ext: 62421

Email: [email protected]

facility status investigator Vancouver General Hospital Ben Chew, MD Principal Investigator Ryan Paterson, MD Sub-Investigator
Location Countries


Verification Date

March 2020

Responsible Party

Responsible party type: Principal Investigator

Investigator affiliation: University of British Columbia

Investigator full name: Ben Chew, MD

Investigator title: Associate Professor

Has Expanded Access No
Condition Browse
Number Of Arms 1
Arm Group

Arm group label: Dietary supplement

Arm group type: Experimental

Description: Calcium Carbonate

Patient Data No
Study Design Info

Allocation: N/A

Intervention model: Single Group Assignment

Primary purpose: Prevention

Masking: None (Open Label)

Source: ClinicalTrials.gov