Renal and Urological Disorders Associated With Inflammatory Bowel Disease

Renal and urinary tract complications related to inflammatory bowel disease (IBD) have been relatively understudied in the literature compared with other extraintestinal manifestations. Presentation of these renal manifestations can be subtle, and their detection is complicated by a lack of clarity regarding the optimal screening and routine monitoring of renal function in IBD patients. Urolithiasis is the most common manifestation. Penetrating Crohn's disease involving the genitourinary system as an extraintestinal complication is rare but associated with considerable morbidity. Some biologic agents used to treat IBD have been implicated in progressive renal impairment, although differentiating between drug-related side effects and deteriorating kidney function due to extraintestinal manifestations can be challenging. The most common findings on renal biopsy of IBD patients with renal injury are tubulointerstitial nephritis and IgA nephropathy, the former also being associated with drug-induced nephrotoxicity related to IBD medication. Amyloidosis, albeit rare, must be diagnosed early to reduce the chance of progression to renal failure. In this review, we evaluate the key literature relating to renal and urological involvement in IBD and emphasize the high index of suspicion required for the prompt diagnosis and treatment of these manifestations and complications, considering the potential severity and implications of acute or chronic loss of renal function. We also provide suggestions for future research priorities.

[Renal granulomatous nephritis: Histopathological point of view]

Granulomatous interstitial nephritis (NIG) is a rare form of interstitial nephritis that can be related to acute or chronic clinical presentation. NIG is characterized by granulomas located to the renal interstitium and composed of either epithelioid histiocytes with giant cells and/or of foreign body reaction. The symptoms are unspecific and associate varying degrees of renal failure with abnormal urinanalysis. Extra-renal signs may point to systemic disease. Pathological examination from kidney percutaneous biopsy or surgical resection is required to assert NIG diagnosis and to guide the etiological research. The main causes of NIG are sarcoidosis, drug reactions, mycobacterial infections and crystalline nephropathies. Sarcoidosis is characterized by non-necrotic and well-formed giant cell epithelioid interstitial granulomas. Drug reactions have less well-defined granulomas with inconstant eosinophils. The presence of caseous necrosis within giant cell and epithelioid granulomas leads to infectious NIG diagnosis (tuberculosis and fungal infection). Identification of crystals within foreign body reaction can be improved by polarized light study. Xanthogranulomatous pyelonephritis and malakoplakia are rarer causes of NIG characterized by patches of histiocytes associated with inconstant giant cells. Differential diagnoses of NIG are represented by granulomatous reactions centered on glomeruli and vessels (vasculitis and emboli of cholesterol crystals). Less than 10% of NIG are idiopathic. The prognosis and the treatment vary according to the cause. The factors of poor renal prognosis are chronic irreversible tubulo-interstitial injury (tubular atrophy and interstitial fibrosis).

The Association of Mesalamine With Kidney Disease

The package inserts for products containing 5-aminosalicylic acid, or mesalamine, include the following language regarding the risk of adverse kidney effects: "renal impairment, including minimal change nephropathy, acute and chronic interstitial nephritis, and rarely renal failure, has been reported in patients given products such as mesalamine delayed-release tablets that contain mesalamine or are converted to mesalamine." In this article, we review the data regarding this nephrotoxicity and the recommendations regarding appropriate monitoring. Chronic interstitial nephritis is a rare occurrence in patients treated with these drugs for Crohn disease and ulcerative colitis. Patients often present with asymptomatic reductions in glomerular filtration rate, without accompanying pyuria, skin lesions, or eosinophilia, unlike cases of acute interstitial nephritis. Drug cessation is usually associated with improved kidney function. However, if left undetected, more prolonged exposure to the drug can lead to irreversible kidney failure and end-stage kidney disease. No convincing studies demonstrate efficacy of treatment with corticosteroids. Frequent monitoring of serum creatinine, especially in the first years after initiation of therapy, is recommended.

[Renal and Urinary Manifestations of Inflammatory Bowel Disease]

The incidence of inflammatory bowel disease (IBD) is increasing rapidly and extra-intestinal manifestations in IBD are also increasing. The prevalence of renal and urinary involvement in IBD ranges from 4-23%. Nephrolithiasis is the most common urinary complication in IBD patients. Parenchymal renal disease is rare but has been well documented and presents most commonly as glomerulonephritis or tubulointerstitial nephritis. The overall morbidity of IBD-related renal manifestations is significant. Therefore, a high index of clinical suspicion and optimal monitoring of the renal function are needed for the early diagnosis and prevention of IBD-related renal manifestations and complications.

Tubulointerstitial Nephritis Associated with Enteritis and Sacroiliitis

The association between sacroiliitis and tubulointerstitial nephritis has not been reported. A 28-year-old man with a history of clinically diagnosed ulcerative colitis (4 years earlier) and sacroiliitis (6 months earlier) developed renal dysfunction 9 months ago, which progressed thereafter. We diagnosed him with tubulointerstitial nephritis by a renal biopsy, for which we started steroid therapy. Subsequently, his renal dysfunction, sacroiliitis, and enteritis partially improved. A pathological analysis of the kidney and intestine revealed lymphocyte infiltration and non-caseating granuloma in both organs. The similarities in the pathological findings and treatment response suggested a pathogenetic association between tubulointerstitial nephritis, enteritis, and sacroiliitis.

[Tubulointerstitiel nephritis and Crohn's disease, nephrotoxicity or extraintestinal manifestation of Crohn's disease? About a case]

Extraintestinal manifestations in inflammatory bowel disease involve most frequently the joints, the skin, the eyes, the liver and the biliary tract. Renal involvement is rare, and manifested as nephrolithiasis, tubulointerstitial nephritis, glomerulonephritis and amyloidosis. In patients with inflammatory bowel disease, renal disease is most frequently due to treatment nephrotoxicity and rarely as a guenine extraintestinal manifestation of inflammatory bowel disease. We are reporting a case of tubulointerstitial nephritis as an extraintestinal manifestation of Crohn's disease and we are explaining the diagnostic difficulty to distinguish this from drug-induced nephrotoxicity.

Infliximab-Induced Tubulointerstitial Nephritis with Image Findings of Striated Nephrogram in Crohn's Disease

Tubulointerstitial nephritis is primary injury to renal tubules and interstititum which could be resulting in decreased renal function. The acute and chronic forms are most often due to allergic drug reactions or to infections. Tubulointerstitial nephritis in Crohn's disease has rarely been reported. Imaging findings of a striated nephrogram on enhanced computed tomography (CT) could represent the clinical state of tubulointerstitial nephritis. This is the first report of tubulointerstitial nephritis caused by infliximab, monoclonal antibody against human tumor necrosis factor-α, showing striated nephrograms in Crohn's disease. The case of a 28-year-old man treated with infliximab for Crohn's disease is described. Infliximab was added to his maintenance therapy, and bowel symptoms were stable. The patient presented with a 2-month history of fever and an elevated C-reactive protein after infliximab administration for 4.5 years. Contrast-enhanced CT showed striated nephrograms in both kidneys. Urinalysis showed no abnormal findings. The pathological diagnosis on CT-guided percutaneous renal needle biopsy was drug-induced tubulointerstitial nephritis because of eosinophilic infiltration with neutrophils mainly in the tubulointerstitial areas. The imaging findings of striated nephrogram are important for the diagnosis of tubulointerstitial nephritis. Tubulointerstitial nephritis could be caused by drug-induced inflammation or direct extension of Crohn's disease as an extra-interstitial manifestation. The treatment strategies for these two diseases are contradictory to each other and inappropriate treatment could worsen the renal function. Needle biopsy is therefore indispensable for differential diagnosis.

Renal Manifestations of Inflammatory Bowel Disease

Renal and urinary involvement has been reported to occur in 4% to 23% of inflammatory bowel disease (IBD) patients. Parenchymal renal disease is rare and most commonly affects glomerular and tubulointerstitial compartments. The most common findings on renal biopsy of IBD patients are IgA nephropathy and tubulointerstitial nephritis. Overall morbidity of IBD-related renal manifestations is significant, and there is often only a short window of injury reversibility. This, along with subtle clinical presentation, requires a high index of suspicion and routine monitoring of renal function. There are no established guidelines for the optimal screening and monitoring of renal function in IBD patients.

Histopathologic review of granulomatous inflammation

Granulomatous inflammation is a histologic pattern of tissue reaction which appears following cell injury. Granulomatous inflammation is caused by a variety of conditions including infection, autoimmune, toxic, allergic, drug, and neoplastic conditions. The tissue reaction pattern narrows the pathologic and clinical differential diagnosis and subsequent clinical management. Common reaction patterns include necrotizing granulomas, non necrotizing granulomas, suppurative granulomas, diffuse granulomatous inflammation, and foreign body giant cell reaction. Prototypical examples of necrotizing granulomas are seen with mycobacterial infections and non-necrotizing granulomas with sarcoidosis. However, broad differential diagnoses exist within each category. Using a pattern based algorithmic approach, identification of the etiology becomes apparent when taken with clinical context. The pulmonary system is one of the most commonly affected sites to encounter granulomatous inflammation. Infectious causes of granuloma are most prevalent with mycobacteria and dimorphic fungi leading the differential diagnoses. Unlike the lung, skin can be affected by several routes, including direct inoculation, endogenous sources, and hematogenous spread. This broad basis of involvement introduces a variety of infectious agents, which can present as necrotizing or non-necrotizing granulomatous inflammation. Non-infectious etiologies require a thorough clinicopathologic review to narrow the scope of the pathogenesis which include: foreign body reaction, autoimmune, neoplastic, and drug related etiologies. Granulomatous inflammation of the kidney, often referred to as granulomatous interstitial nephritis (GIN) is unlike organ systems such as the skin or lungs. The differential diagnosis of GIN is more frequently due to drugs and sarcoidosis as compared to infections (fungal and mycobacterial). Herein we discuss the pathogenesis and histologic patterns seen in a variety of organ systems and clinical conditions.

CT and MRI of Rare Extraintestinal Manifestations of Inflammatory Bowel Disease in Children and Adolescents

Inflammatory bowel disease (IBD) is associated with a spectrum of extraintestinal manifestations (EIMs) affecting many organ systems. EIMs can occur in more than 40% of patients with IBD and are associated with significant morbidity. They occur at any time point in the course of disease, often during an active phase of bowel inflammation, but sometimes preceding bowel disease. Prompt recognition of EIMs enables timely and more effective therapy. Physicians who image patients with IBD should be aware of the myriad extraintestinal conditions that may be detected on imaging studies, both within and outside of the abdomen, as they may predate the diagnosis of IBD. Cross-sectional imaging of unusual conditions associated with IBD will be presented, including pathology in the hepatobiliary, pancreatic, genitourinary, musculoskeletal, mucocutaneous, vascular, neurologic, and pulmonary systems.

Granulomatous interstitial nephritis and Crohn's disease

Granulomatous interstitial nephritis has been observed in <1% of native renal biopsies. Here, we describe two patients with granulomatous interstitial nephritis in relation to Crohn's disease. Circulating helper and cytotoxic T cells were highly activated, and both cell types predominated in the interstitial infiltrate, indicating a cellular autoimmune response. After immunosuppressive treatment, renal function either improved or stabilized in both patients. In conclusion, granulomatous interstitial nephritis is a genuine extraintestinal manifestation of Crohn's disease, the treatment of which should include immunosuppressive agents.

[Interstitial nephritis in rheumatic diseases]

Interstitial nephritis is responsible for about 12 % of end-stage renal disease in Germany. It comprises an etiologically heterogenous group of inflammatory renal disorders which primarily affect the renal interstitium and tubuli. Drugs, predominantly antibiotics, nonsteroidal anti-inflammatory drugs and proton pump inhibitors are causative in the majority of cases. Rheumatic diseases frequently affect the kidneys, either the glomeruli or the interstitial tissues. Inflammatory interstitial processes can be accompanied by complex functional tubular disorders. This review gives an overview about clinical and laboratory findings of interstitial nephritis in the context of rheumatic diseases. Sarcoidosis, tubulointerstitial nephritis and uveitis (TINU) syndrome, primary Sjogren's syndrome, and IgG4-related disease often show an interstitial nephritis when the kidneys are affected. Other diseases, such as systemic lupus erythematosus, systemic sclerosis, drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, and granulomatosis with polyangiitis are more rarely associated with predominant interstitial nephritis. Glucocorticoids are the mainstay of therapy for most cases; in refractory cases or when side effects occur, second-line immunosuppressants such as mycophenolate mofetil, azathioprine and others, rarely biologics, can be used.

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).

Clinical Features and HLA Association of 5-Aminosalicylate (5-ASA)-induced Nephrotoxicity in Inflammatory Bowel Disease

BACKGROUND AND AIMS

Nephrotoxicity is a rare idiosyncratic reaction to 5-aminosalicylate (5-ASA) therapies. The aims of this study were to describe the clinical features of this complication and identify clinically useful genetic markers so that these drugs can be avoided or so that monitoring can be intensified in high-risk patients.

METHODS

Inflammatory bowel disease patients were recruited from 89 sites around the world. Inclusion criteria included normal renal function prior to commencing 5-ASA, ≥50% rise in creatinine any time after starting 5-ASA, and physician opinion implicating 5-ASA strong enough to justify drug withdrawal. An adjudication panel identified definite and probable cases from structured case report forms. A genome-wide association study was then undertaken with these cases and 4109 disease controls.

RESULTS

After adjudication, 151 cases of 5-ASA-induced nephrotoxicity were identified. Sixty-eight percent of cases were males, with nephrotoxicity occurring at a median age of 39.4 years (range 6-79 years). The median time for development of renal injury after commencing 5-ASA was 3.0 years (95% confidence interval [CI] 2.3-3.7). Only 30% of cases recovered completely after drug withdrawal, with 15 patients requiring permanent renal replacement therapy. A genome-wide association study identified a suggestive association in the HLA region (p = 1×10(-7)) with 5-ASA-induced nephrotoxicity. A sub-group analysis of patients who had a renal biopsy demonstrating interstitial nephritis (n = 55) significantly strengthened this association (p = 4×10(-9), odds ratio 3.1).

CONCLUSIONS

This is the largest and most detailed study of 5-ASA-induced nephrotoxicity to date. It highlights the morbidity associated with this condition and identifies for the first time a significant genetic predisposition to drug-induced renal injury.

Etiological diagnosis of granulomatous tubulointerstitial nephritis in the tropics

Background

Granulomatous tubulointerstitial nephritis (GIN) is common due to infections, drugs or sarcoidosis. However, the cause is often difficult to establish and the studies are limited. We studied the etiology of GIN and compared the clinical and histological features and outcome in different etiologies at a tertiary care center in North India.

Methods

Renaö biopsies from GIN cases diagnosed from January 2004 to April 2014 were retrieved. Stain for acid fast bacilli was performed in all biopsies. Etiological diagnosis was based on clinical features, extra-renal manifestations, radiology, history of drug intake and demonstration of infective agent. Tissue PCR for tubercular DNA was performed in seven biopsies.

Results

Seventeen GIN patients [mean age 35 ± 15 years; males 11] were identified. Tuberculosis was the commonest etiology followed by idiopathic, sarcoidosis and fungal. Both tuberculosis and sarcoidosis patients presented with subnephrotic proteinuria and raised serum creatinine. Acid fast bacilli were demonstrated in 1/9 and necrosis was demonstrated in 3/9 granulomas in tuberculosis. Tissue PCR for tubercular DNA was positive in six TB patients and negative in one sarcoidosis patient. Patients responded well to appropriate therapy.

Conclusion

Etiological diagnosis of GIN is essential for timely and appropriate therapy. Tuberculosis is the commonest etiology (53%) in the tropics. Necrosis in granuloma, demonstration of acid fast bacilli, blood interferon gamma release assay and urine culture is not sensitive for the diagnosis of tuberculosis in GIN. Our findings suggest that tissue PCR for tuberculosis performed in an appropriate clinical setting is useful in the diagnostic evaluation of GIN.