Insights into renal and urological complications of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic condition characterized by immune-mediated inflammation in the gastrointestinal tract, which follows a relapsing and remitting course. Apart from affecting the gastrointestinal tract, IBD also has extra-intestinal manifestations (EIMs). While the etiology of extraintestinal manifestation remains unclear, it is theorized to be based on immunological responses influenced by genetic factors. Renal involvement is one of the EIMs observed in ulcerative colitis and Crohn's disease. The renal manifestations in IBD patients encompass a range of conditions including nephrolithiasis, amyloidosis, tubulointerstitial nephritis, glomerulonephritis (GN), obstructive pathologies, and chronic kidney disease (CKD). The incidence of CKD in IBD patients varies from 5%-15%. The decline in renal function can stem from various factors such as direct inflammatory damage to the kidneys leading to glomerular or tubular injury, or from complications like recurrent stones, amyloidosis, or GN. Additionally, nephrotoxic medications used in treating IBD, such as TNF-α inhibitors, calcineurin inhibitors, and aminosalicylates, can exacerbate the decline in renal function. Currently, there is a lack of consensus regarding these patients' screening and renal function monitoring. This review aims to assess the existing literature on the different renal complications among individuals with IBD, shedding light on their pathophysiology and management.

Therapeutic effects of biological treatments on AA amyloidosis associated with inflammatory bowel disease: a case report and literature review

AA amyloidosis is a rare and significant complication of long-term inflammation that can be caused by a variety of disorders, including inflammatory bowel disease, and is linked to an increased risk of morbidity and mortality. To date, there has been no effective direct treatment, and treatment aims at treating the underlying condition with potent immunosuppression to limit inflammatory activity and, as a result, switch off amyloidogenesis. Theoretically, biological treatment can control AA amyloidosis by inducing and maintaining inflammatory bowel disease remission and inhibiting the synthesis of Serum Amyloid A, which is an acute phase reactant and precursor protein of AA amyloidosis that accumulates in the organs. We report the first case of ustekinumab's therapeutic effect after infliximab's loss of response in AA amyloidosis associated with Crohn's disease. We also conducted a literature review of the therapeutic effect of biological treatment on AA amyloidosis.

Renal Amyloidosis and Crohn Disease

Background: Secondary amyloidosis, a rare complication of Crohn disease (CD), is triggered by persistent systemic inflammation. Kidney involvement is the most frequent manifestation and is often characterized by nephrotic syndrome and kidney failure. This complication usually appears in patients with long-standing disease and is associated with increased morbidity and mortality risk. Diagnosis is by microscopic amyloid observation of tissue biopsy, and when the diagnosis is confirmed, the therapeutic objective is disease activity control. Response assessment is challenging because of a lack of reliable biomarkers.

Case Report: A 56-year-old male with a long-standing history of CD treated with a tumor necrosis factor-α inhibitor presented with an acute elevation of creatinine in association with clinical and laboratory markers of nephrotic syndrome. Kidney biopsy revealed renal amyloidosis. After treatment adjustment, although a stable creatinine was achieved, the patient had persistent impaired glomerular filtration rate.

Conclusion: As a systemic chronic inflammatory disorder, CD may present multisystemic morbidity, for which increased awareness among gastroenterologists is warranted. Renal amyloidosis is an infrequent extraintestinal complication of CD that may lead to chronic kidney impairment. Although evidence-based treatment is lacking, disease activity control is pivotal for management.

Amyloidosis in Inflammatory Bowel Disease: A Systematic Review of Epidemiology, Clinical Features, and Treatment

BACKGROUND AND AIMS

Amyloidosis is a rare complication of inflammatory bowel disease [IBD]; its low prevalence has hindered both descriptive and therapeutic studies. The aim of this study was to estimate the prevalence of amyloidosis in IBD and the risk factors associated with this complication.

METHODS

This paper presents an observational study, followed by a systematic review of the epidemiological and clinical characteristics of the disease and a review of the diagnostic and therapeutic options.

RESULTS

The prevalence of amyloidosis among IBD patients is 0.53% (95% confidence interval [CI]: 0.32-0.75), although epidemiological data suggest that it may be under-diagnosed. The phenotype most frequently associated with amyloidosis is males with aggressive and extensive Crohn's disease, fistulising behaviour, perianal disease, and extra-intestinal complications, with the development of proteinuria and renal failure.

CONCLUSIONS

Identifying risk factors of amyloidosis in IBD patients and screening for proteinuric renal dysfunction are useful to improve diagnostic accuracy. Referral of biopsies to a tertiary centre should also be considered, to improve diagnostic accuracy. Although there is no reliable evidence on the effectiveness of treatment, it seems reasonable to treat the underlying disease with potent immunosuppression to minimise inflammatory activity, thereby switching off amyloidogenesis.

Renal Involvement in Inflammatory Bowel Diseases

The prevalence of extraintestinal manifestations in inflammatory bowel diseases varies from 6% to 46%. The aetiology of extraintestinal manifestations remains unclear. There are theories based on an immunological response influenced by genetic factors. Extraintestinal manifestations can involve almost every organ system. They may originate from the same pathophysiological mechanism of intestinal disease, or as secondary complications of inflammatory bowel diseases, or autoimmune diseases susceptibility. The most frequently involved organs are the joints, skin, eyes, liver and biliary tract. Renal involvement has been considered as an extraintestinal manifestation and has been described in both Crohn's disease and ulcerative colitis. The most frequent renal involvements in patients with inflammatory bowel disease are nephrolithiasis, tubulointerstitial nephritis, glomerulonephritis and amyloidosis. The aim of this review is to evaluate and report the most important data in the literature on renal involvement in patients with inflammatory bowel disease. Bibliographical searches were performed of the MEDLINE electronic database from January 1998 to January 2015 with the following key words (all fields): (inflammatory bowel disease OR Crohn's disease OR ulcerative colitis) AND (kidney OR renal OR nephrotoxicity OR renal function OR kidney disease OR renal disease OR glomerulonephritis OR interstitial nephritis OR amyloidosis OR kidney failure OR renal failure) AND (5-aminosalicylic acid OR aminosalicylate OR mesalazine OR TNF-α inhibitors OR cyclosporine OR azathioprine OR drugs OR pediatric).