The purpose of this study is to learn more about the risk factors associated with kidney stone formation. The particular focus is on Oxalobacter formigenes, a bacterium in the colon that metabolizes dietary oxalate and is excreted in the stool; it is present in about 40% of the normal adult population. The absence of O. formigenes could reduce the metabolism of oxalate in the colon, resulting in its excretion by the kidneys, and thus, a greater likelihood of developing calcium oxalate kidney stones. This hypothesis was tested among 247 patients with recurrent calcium oxalate kidney stones from three Boston Hospitals (Massachusetts General Hospital, Boston Medical Center, and St. Elizabeth’s Medical Center) and Duke University Medical Center in Durham, North Carolina, compared with 259 age and gender-matched controls. The controls consist of housemates or friends of other stone patients from the same hospitals. The presence of the bacterium was demonstrated by culture of fecal smears. After being screened and recruited for the study, information regarding factors that might affect O. formigenes or the risk of kidney stones was obtained from the participants by telephone interview and a self-completed dietary questionnaire. A subset of 139 cases and 138 controls completed 24 hour urine collections for the assessment of urinary volume, oxalate, and other factors measured under their usual dietary conditions. Data collection has been completed. The main results show a strong inverse association between colonization and the development of recurrent stones, with an odds ratio of 0.4 This supports the hypothesis, although surprisingly, there was little relationship between O. formigenes and urinary oxalate. Further analyses are in progress.
Investigators:
David W. Kaufman, Sc.D, Principal Investigator
Slone Epidemiology Center, Boston University
Gary C. Curhan, M.D., Sc.D, Co-Investigator
Partners Center for Kidney Stone Disease,
Massachusetts General Hospital
David R. Cave, M.D., Ph.D, Co-Investigator
Division of Gastroenterology, St. Elizabeth’s Medical Center
Stephen P. Dretler, M.D.
Massachusetts General Hospital
Dianne Sacco, M.D.
Wang Ambulatory Care Center, Massachusetts General Hospital
Richard K. Babayan, M.D.
Chair, Department of Urology, Boston Medical Center
David S. Wang, M.D.
Department of Urology, Boston Medical Center
Glenn M. Preminger, M.D.
Division of Urologic Surgery, Duke University Medical Center
Study Staff:
Judith P. Kelly, M.S., Epidemiologist
Theresa Anderson, R.N., Project Coordinator
Lisa Crowell, R.N., Nurse Interviewer
Jean McDonald, Research Assistant
Source of funding:
NIDDK/NIH
Study Period:
August 2003 – December 2007
Analysis:
Ongoing
Publications:
Link to Publications
Contact information:
Teri Anderson: (617) 734-6006
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