April 5, 2019
Disease Week: Renal Manifestations of Inflammatory Bowel Disease (IBD)
Inflammatory bowel disease (IBD) is a condition characterized by chronic inflammation of the gastrointestinal tract with the two most common types Crohn disease and ulcerative colitis. While renal and urinary involvement in IBD is not uncommon, renal parenchymal disease is rare and most commonly affects the glomerular and tubulointerstitial compartments.
The most common findings on renal biopsy of IBD patients are IgA nephropathy and tubulointerstitial nephritis, and this occurrence may represent a common pathogenic mechanism. Although several cases of tubulointerstitial nephritis have been related to drug exposure, there is increasing evidence that this finding may also represent a true extraintestinal manifestation of disease.
The overall morbidity of IBD-related renal manifestations is significant, and there is often only a short window of injury reversibility. This, along with an often subtle clinical presentation, requires a high index of suspicion and likely routine monitoring of renal function, particularly in the elderly and those with co-morbidities. There are currently no established guidelines for the optimal screening and monitoring of renal function in IBD patients. However, there appears to be general consensus that renal function should be assessed prior to initiation of drug therapy, with ongoing monitoring of renal function every 3 months to 6 months the first year, followed by annual to semiannual monitoring thereafter.