تشکیل سنگ کلیه در بیماران مبتلا به بیماری التهابی روده در جامعه Nephrolithiasis in patients with inflammatory bowel disease in the community

Nephrolithiasis represents a serious health problem in some countries. For instance, it has been reported that 5%–۱۵% of the general population in the United States will develop renal calculi in their lifetime, with the five-year recurrence rate ranging from 30% to 50%. Diet and gender are considered to be risk factors for the development of renal calculi, the incidence of which is higher in males. In the United States, nephrolithiasis accounts for 1% of all hospitalizations and is responsible for annual medical costs of two billion dollars.1–۴ Chronic diseases that are accompanied by intermittent diarrhea, such as ulcerative colitis and Crohn’s disease, are directly associated with the formation of renal calculi. Historical studies have demonstrated that the prevalence of symptomatic nephrolithiasis is higher in patients with inflammatory bowel disease (IBD, 7%–۱۵%) than in the general population (1%–۱۵%), typically in patients who have undergone extensive small bowel resection or in those with persistent severe small bowel inflammation.5,6 Extensive small bowel resections can lead to steatorrhea and increase the risk of hyperoxaluria by 28%, because these interventions can lead to loss of the bacterium Oxalobacter formigenes or chelation of free calcium in the colonic lumen by lipids.7 In addition, it has been reported that patients who have an ostomy are more likely to develop uric acid stones than calcium oxalate stones.6,8,9 In the last 10 years, new therapeutic approaches to patients with IBD have emerged and completely changed the natural history of these diseases; the impact of such approaches is reflected not only in lower rates of surgery but also in better prognoses, fewer hospitalizations, and better improved quality of life.9 Whether this has changed the prevalence of and risk factors for renal calculi in this patient population is unknown. The objective of the present study was to determine prospectively the prevalence of nephrolithiasis in a communitybased population of patients with IBD who had not undergone surgery. In addition, we sought to identify risk factors for formation of renal calculi in this population.