Renal manifestations and complications of inflammatory bowel disease

Thiadiazolidinone-8 Ameliorates Inflammation Associated with Experimental Colitis in Mice

Thiadiazolidinone-8 (TDZD-8) is an effective thiadiazolidinone derivate that is able to suppress the expression of inflammatory cytokines; it also presents tissue protective actions by glycogen synthase kinase (GSK)-3β inhibition, promoting thus an anti-inflammatory effect. Since inflammatory bowel disease is a chronic disease with reduced quality of life, where currently available therapies are only able to induce or maintain the patient in remission, it is crucial to investigate new pharmacological approaches. The main objective of this study was to evaluate the effect of TDZD-8 in 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Male CD-1 mice with TNBS-induced colitis were treated with a daily dose of TDZD-8 5 mg/kg/day IP during 4 days. The anti-inflammatory properties of TDZD-8 in the TNBS-induced colitis were confirmed by suppression of pro-inflammatory mediators, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β and myeloperoxidase, as well as by the significant increase of the anti-inflammatory cytokine, IL-10. These treated mice also presented a reduction in fecal hemoglobin and alkaline phosphatase, suggesting a beneficial effect of TDZD-8. Furthermore, renal and hepatic biomarkers remained stabilized after treatment. In conclusion, TDZD-8 reduces the inflammatory response associated with TNBS-induced colitis in mice, and modulation of GSK-3β seems to be an interesting pharmacological target in colitis.

Tubulointerstitial nephritis: diagnosis, treatment, and monitoring

Tubulointerstitial nephritis (TIN) is a frequent cause of acute kidney injury (AKI) that can lead to chronic kidney disease (CKD). TIN is associated with an immune-mediated infiltration of the kidney interstitium by inflammatory cells, which may progress to fibrosis. Patients often present with nonspecific symptoms, which can lead to delayed diagnosis and treatment of the disease. Etiology can be drug-induced, infectious, idiopathic, genetic, or related to a systemic inflammatory condition such as tubulointerstitial nephritis and uveitis (TINU) syndrome, inflammatory bowel disease, or immunoglobulin G4 (IgG4)-associated immune complex multiorgan autoimmune disease (MAD). It is imperative to have a high clinical suspicion for TIN in order to remove potential offending agents and treat any associated systemic diseases. Treatment is ultimately dependent on underlying etiology. While there are no randomized controlled clinical trials to assess treatment choice and efficacy in TIN, corticosteroids have been a mainstay of therapy, and recent studies have suggested a possible role for mycophenolate mofetil. Urinary biomarkers such as alpha1- and beta2-microglobulin may help diagnose and monitor disease activity in TIN. Screening for TIN should be implemented in children with inflammatory bowel disease, uveitis, or IgG4-associated MAD.

Rheumatologic and extraintestinal manifestations of inflammatory bowel diseases

Inflammatory bowel diseases (IBDs) often present as a complex inflammatory process wherein colon lesions (ulcerative colitis, UC) or widespread ulceration and fissure (Crohn's disease, CD) might be accompanied by ancillary extraintestinal manifestations (EIMs) that could involve almost every organ system, but also by autoimmune disorders ranging from psoriasis and rheumatoid arthritis to connective tissue diseases. Certain EIMs are more common related to the activity of the IBD (joint, skin, ocular and oral manifestations), other EIMs typically run a course independent of the IBD activity (hepatobiliary disorders) and some are non-specific disorders (osteoporosis and amyloidosis). This paper reviews the most common extraintestinal and rheumatologic manifestations of UC and CD. They may produce greater morbidity than the underlying intestinal disease and may even be the initial presenting symptoms of the IBD. Thus, early recognition of these manifestations should help guide therapy that will reduce overall morbidity in affected patients. Key Message A complete review on the most common extraintestinal and rheumatologic manifestations of ulcerative colitis and Crohn's disease.

Anti-Inflammatory Effect of Erythropoietin in the TNBS-induced Colitis

Erythropoietin is a potent stimulator of erythroid progenitor cells, which is able to inhibit NF-kB activation, due to its pleiotropic properties, thus promoting an anti-inflammatory effect. As inflammatory bowel disease is a chronic disease with reduced quality of life, and the current pharmacotherapy only induces or maintains the patient in remission, there is a crucial need of new pharmacological approaches. The main objective of this study was to evaluate the effect of erythropoietin in the TNBS-induced colitis model in mice with a normal intestinal flora. Mice with TNBS-induced colitis were treated with a daily dose of erythropoietin at 500 IU/kg bw/day and 1000 IU/Kg bw/day IP during 4 days. As to clinical symptoms/signs, erythropoietin attenuated the decreased body-weight and reduced diarrhoea and oedema of the anus registered in the non-treated mice group in a dose-dependent manner. The anti-inflammatory properties of erythropoietin in the TNBS-induced colitis were confirmed by suppression of pro-inflammatory mediators, such as TNF-α, IL-1β and MPO, as well as a significant increase in the anti-inflammatory cytokine, IL-10, was promoted. These treated mice also presented a reduction in haemoglobin faecal and ALP, suggesting a beneficial effect of erythropoietin in the haemorrhagic focus and destruction of the enterocyte associated with the colon injury induced by TNBS, respectively. The histopathological score was reduced after treatment with erythropoietin, decreasing the severity and extension of the colitis. Furthermore, renal and hepatic biomarkers, as well as haematocrit concentration, remained stabilized after treatment. In conclusion, erythropoietin reduces the inflammatory response associated with TNBS-induced colitis in mice.

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.

Prevalence and Characteristics of Extra-intestinal Manifestations in a Large Cohort of Greek Patients with Inflammatory Bowel Disease

BACKGROUND AND AIMS

Extraintestinal manifestations [EIMs] are common in inflammatory bowel disease [IBD]. Data on epidemiology and risk factors of EIMs in IBD patients are limited. The aim of this study was to investigate the prevalence of EIMs in a large cohort of Greek IBD patients and identify risk factors for their development.

METHODS

The study population consisted of IBD patients, who were followed in eight tertiary Greek hospitals. Demographic and clinical characteristics of patients were analysed. The diagnosis of EIMs was based on standard criteria and on specialist consultation.

RESULTS

In total, 1860 IBD patients (1001 with Crohn's disease [CD], 859 with ulcerative colitis [UC]) were registered. Among them 615 [33.1%] exhibited at least one EIM; 238 patients [38.6%] developed an EIM before IBD diagnosis. An association between active IBD and presence of an EIM was established in 61.1% of the patients. Arthritic [peripheral arthritis], mucocutaneous [erythema nodosum], and ocular [episcleritis] were the most common manifestations. EIMs were more prevalent in females, patients with CD, smokers [for all p <0.0001], patients with extensive UC [p = 0.007], and patients with a previous appendectomy [p < 0.0001] or a major IBD-related surgery [p = 0.012].

CONCLUSIONS

About one-third of Greek IBD patients developed at least one EIM. Of those, more than one-third had their EIM diagnosed before IBD, and in about two-thirds it was related to disease activity. EIMs were more frequently present in females and patients with extensive UC in multivariate analysis.

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).

Inflammatory bowel disease imaging: Current practice and future directions

The purpose of this paper is to evaluate the role of imaging in inflammatory bowel disease (IBD), including detection of extraluminal complications and extraintestinal manifestations of IBD, assessment of disease activity and treatment response, and discrimination of inflammatory from fibrotic strictures. IBD is a chronic idiopathic disease affecting the gastrointestinal tract that is comprised of two separate, but related intestinal disorders; Crohn’s disease and ulcerative colitis. The paper discusses, in detail the pros and cons of the different IBD imaging modalities that need to be considered in order to optimize the imaging and clinical evaluation of patients with IBD. Historically, IBD evaluation of the bowel has included imaging to assess the portions of the small bowel that are inaccessible to optical endoscopic visualization. This traditionally was performed using barium fluoroscopic techniques; however, cross-sectional imaging techniques (computed tomography and magnetic resonance imaging) are being increasingly utilized for IBD evaluation because they can simultaneously assess mural and extramural IBD manifestations. Recent advances in imaging technology, that continue to improve the ability of imaging to noninvasively follow disease activity and treatment response, are also discussed. This review article summarizes the current imaging approach in inflammatory bowel disease as well as the role of emerging imaging modalities.

Peculiar Presentation of Ulcerative Colitis

Ulcerative colitis (UC) is a chronic inflammatory and recurrent disorder that is characterized by bowel inflammation. Among the extraintestinal manifestations (EIMs) that associate UC are the joints and renal manifestations. Joint affection in the form of arthritis can precede the intestinal manifestations of UC. However, renal affection with amyloidosis does not precede the UC diagnosis. Herein, we report a case of 26-year-old male diagnosed with UC after having peripheral arthritis for long time in addition to spondylitis and kidney amyloidosis.

Solid Organ Transplantation in Patients with Inflammatory Bowel Diseases (IBD): Analysis of Transplantation Outcome and IBD Activity in a Large Single Center Cohort

Background

Currently, limited data of the outcome of inflammatory bowel disease (IBD) in patients after solid organ transplantation (SOT) are available. We aimed to analyze effects of SOT on the IBD course in a large IBD patient cohort.

Methods

Clinical data from 1537 IBD patients were analyzed for patients who underwent SOT (n = 31) between July 2002 and May 2014. Sub-analyses included SOT outcome parameters, IBD activity before and after SOT, and efficacy of IBD treatment.

Results

4.74% of patients with ulcerative colitis (UC) and 0.84% of patients with Crohn’s disease (CD) underwent SOT (p = 2.69 x 10⁻⁶, UC vs. CD). 77.4% of patients with SOT underwent liver transplantation (LTx) with tacrolimus-based immunosuppressive therapy after SOT. All LTx were due to primary sclerosing cholangitis (PSC) or PSC overlap syndromes. Six patients (19.4%) required renal transplantation and one patient (3.2%) heart transplantation. A survival rate of 83.9% after a median follow-up period of 103 months was observed. Before SOT, 65.0% of patients were in clinical remission and 5 patients received immunosuppressive therapy (16.1%). After SOT, 61.0% of patients were in remission (p = 1.00 vs. before SOT) and 29.0% required IBD-specific immunosuppressive or anti-TNF therapy (p = 0.54 vs. before SOT). 42.9% of patients with worsening of IBD after SOT were at higher risk of needing steroid therapy for increased IBD activity (p = 0.03; relative risk (RR): 10.29; 95% CI 1.26–84.06). Four patients (13.0%) needed anti-TNF therapy after SOT (response rate 75%).

Conclusions

SOT was more common in UC patients due to the higher prevalence of PSC-related liver cirrhosis in UC. Despite mainly tacrolimus-based immunosuppressive regimens, outcome of SOT and IBD was excellent in this cohort. In this SOT cohort, concomitant immunosuppressive therapy due to IBD was well tolerated.

Magnetic resonance colonography including diffusion-weighted imaging in children and adolescents with inflammatory bowel disease: do we really need intravenous contrast?

OBJECTIVES

Magnetic resonance colonography (MRC) is a well-accepted, noninvasive imaging modality for the depiction of inflammatory bowel disease. Diffusion-weighted imaging (DWI) is very helpful to display inflammatory lesions. The aim of this retrospective study was to assess whether intravenous contrast is needed to depict inflammatory lesions in bowel magnetic resonance imaging if DWI is available.

MATERIALS AND METHODS

Thirty-seven patients (23 females, 14 males; mean age, 14.6 years) underwent MRC on a 1.5-T scanner (MAGNETOM Avanto; Siemens). Contrast-enhanced T1-weighted (ce-T1-w) sequences and DWI sequences in axial and coronal planes (b = 50, 500, 1000) were acquired. Two reviewers evaluated (1) DWI, (2) ce-T1-w MRC, as well as (3) DWI and ce-T1-w MRC concerning lesion conspicuity. The preferred b value was assessed. Colonoscopy was performed within 1 week, including biopsies serving as the reference standard. Sensitivities and specificities were calculated, and interobserver variability was assessed.

RESULTS

Mean sensitivity and specificity of the 2 readers for the depiction of inflammatory lesions were 78.4%/100% using ce-T1-w MRC, 95.2%/100% using DWI, and 93.5%/100% combining both imaging techniques compared with colonoscopy including results of the histopathological samples. In 6 patients, inflammatory lesions were only detected by DWI; in another 6 patients, DWI detected additional lesions. The κ values for the 2 readers were excellent (k = 0.92-0.96). The preferred b value with the best detectability of the lesion was b1000 in 28 of the 30 patients (93.3%) with restricted diffusion.

CONCLUSIONS

Diffusion-weighted imaging of the bowel identified inflammatory lesions with high accuracy and revealed lesions that were not detectable with ce-T1-w imaging alone. A b value of 1000 showed the best lesion detectability.

Management of arthropathy in inflammatory bowel diseases

The most common extra-intestinal manifestation in patients with inflammatory bowel disease (IBD) is articular involvement, with a prevalence ranging between 17% and 39%. It is frequently characterized by an involvement of the axial joints but may also be associated with peripheral arthritis. The target of therapy in the management of arthritis associated with IBD is to reduce the inflammation and prevent any disability and/or deformity. This requires active cooperation between gastroenterologist and rheumatologist. The treatment of axial involvement has focused on the combination of exercise with nonsteroidal anti-inflammatory drugs. Immunomodulators have been efficacious in patients with peripheral arthritis and other extra-intestinal manifestations, but they are not effective for the treatment of axial symptoms of spondylitis. Tumor necrosis factor (TNF) α inhibitors have been proven to be highly effective in the treatment of IBD patients which are steroid-dependent or refractory to conventional therapy and in patients with associated articular manifestations. The treatment of peripheral involvement and/or enthesitis and/or dactylitis is based on local steroid injections, while sulfasalazine and/or low doses of systemic steroids may be useful in case of inadequate response to intra-articular steroids. Sulfasalazine induces only a little improvement in peripheral arthritis. Immunomodulators such as methotrexate, azathioprine, cyclosporine and leflunomide show their efficacy in some patients with peripheral arthritis and other extra-intestinal components. TNF-α inhibitors should be considered the first-line therapeutic approach when moderate-to-severe luminal Crohn's disease or ulcerative colitis is associated with polyarthritis. The aim of this review is to provide a fair summary of current treatment options for the arthritis associated with IBD.

Articular and other Immune-Mediated Extra-Intestinal Manifestations in Inflammatory Bowel Diseases

The articular involvement in patients with inflammatory bowel diseases is included in the group of immune-mediated extra-intestinal manifestations, occurring approximately in a range from 6.2–36% of the patients. This group is also made up of the skin and eyes manifestations, that usually but not invariably are correlated with intestinal inflammatory disease activity. Rheumatic manifestations are the most frequent extra-intestinal findings of this group with a prevalence from 20–50%. They are divided into two different clinical subsets: peripheral and axial joint involvement (including sacroiliitis with or without spondylitis). Peripheral arthritis is the most frequent finding in both Crohn's disease and ulcerative colitis, occurring with a frequency ranging from 17–20%, and it is more common in Crohn's disease. Axial involvement is more common in Crohn's disease (5–22%) than in ulcerative colitis (2–6%) and generally the prevalence of sacroiliitis (asymptomatic and symptomatic) is between 12–20% and of spondylitis is between 2–16%. The IBD is also associated with other rheumatic diseases such as rheumatoid arthritis, Sjogren syndrome, Takayasu arteritis and fibromyalgia. The management of patients with EA requires an active cooperation between gastroenterologists and rheumatologists.

Overlap syndrome consisting of PSC-AIH with concomitant presence of a membranous glomerulonephritis and ulcerative colitis

The association of primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) is known as an overlap syndrome (OS). OS can also be described in the setting of concomitant presence of AIH and PSC. These diseases can in some cases be associated with ulcerative colitis. In this case report we describe, to our knowledge, the first case in the literature of a young Caucasian male suffering from ulcerative colitis and an overlap syndrome consisting of an association between PSC-AIH, with the concomitant presence of a membranous glomerulonephritis.

The histopathologic spectrum of kidney biopsies in patients with inflammatory bowel disease

BACKGROUND AND OBJECTIVES

Kidney disease as a complication of inflammatory bowel disease (IBD), including Crohn disease (CD) and ulcerative colitis (UC), has been the subject of case reports. However, no cases series examining IBD and kidney disease has been published to date. This study aimed to evaluate a large series of kidney biopsy specimens from patients with IBD to better define the spectrum and relative frequencies of IBD-associated kidney pathology.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A retrospective review of native kidney biopsy specimens obtained from March 2001 to June 2012 identified 83 patients with IBD. Standard processing of all biopsy specimens included light microscopy, immunofluorescence, and electron microscopy.

RESULTS

There were 45 cases of CD and 38 cases of UC represented. The most common indication for kidney biopsy was acute or chronic kidney failure (63% [52 of 83]) and nephrotic-range proteinuria (16% [13 of 83]). IgA nephropathy was the most common diagnosis (24% [20 of 83]), followed by interstitial nephritis (19% [16 of 83]), arterionephrosclerosis (12% [10 of 83]), acute tubular injury (8% [7 of 83]), proliferative GN (7% [6 of 83]), and minimal-change disease (5% [4 of 83]). When compared, the frequency of IgA nephropathy in IBD was significantly higher than in all other native renal biopsy specimens from the same time period (24% [20 of 83] versus 8% [2734 of 33,630]; P<0.001). Of the 16 cases of interstitial nephritis, 9 (56%) had current or recent past exposure to aminosalicylates, including all cases of granulomatous interstitial nephritis.

CONCLUSIONS

IBD is associated with a spectrum of kidney diseases most commonly affecting the glomerular and tubulointerstitial compartments. IgA nephropathy is the most frequent kidney biopsy diagnosis in IBD and has a significantly higher diagnostic prevalence compared with all non-IBD kidney biopsy specimens. This may reflect a common pathogenic mechanism. Although many cases of tubulointerstitial nephritis are related to aminosalicylate exposure, the possibility of a direct relationship with IBD cannot be ruled out.

Lower fibroblast growth factor 23 levels in young adults with Crohn disease as a possible secondary compensatory effect on the disturbance of bone and mineral metabolism

Fibroblast growth factor 23 (FGF-23) is a bone-derived circulating phosphaturic factor that decreases serum concentration of phosphate and vitamin D, suggested to actively participate in a complex renal-gastrointestinal-skeletal axis. Serum FGF-23 concentrations, as well as various other laboratory parameters involved in bone homeostasis, were measured and analyzed with regard to various diseases and patients' characteristics in 44 patients with Crohn disease (CD) and 20 healthy controls (HCs) included in this cross-sectional study. Serum FGF-23 levels were significantly lower in patients with CD (900.42 ± 815.85pg/mL) compared with HC (1410.94 ± 1000.53pg/mL), p = 0.037. Further analyses suggested FGF-23 as a factor independent from various parameters including age (r = -0.218), body mass index (r = -0.115), 25-hydroxy vitamin D (r = 0.126), parathyroid hormone (r = 0.084), and bone mineral density (BMD) of hip and lumbar (r = 0.205 and r = 0.149, respectively). This observation remained even after multivariate analyses, exhibiting that BMD was not affected by FGF-23, although parameters such as age (p = 0.026), cumulative prednisolone dose (p < 0.0001), and smoking status (p = 0.024) were strong determinants of BMD regarding hip. Lower FGF-23 levels in patients with bowel inflammation are accompanied but not directly correlated with lower vitamin D levels, showing no impact on BMD determination of young adults with CD. The downregulation of serum FGF-23 levels in CD appears as a secondary compensatory effect on the bone and mineral metabolism induced by chronic intestinal inflammation.

Granulomatous Interstitial Nephritis as a Manifestation of Crohn Disease

Granulomatous interstitial nephritis is a rare extraintestinal manifestation of Crohn disease that has been described previously in 4 patients. We report a 23-year-old man with a history of Crohn disease since age 6 years who was admitted to the hospital for weight loss, fever, and bloody diarrhea in the midst of a recent flare up during the past 2 months. Investigations revealed anemia, high erythrocyte sedimentation rate, high C-reactive protein level, and an elevated serum creatinine level. Histopathologic examination of tissue specimens obtained at renal biopsy demonstrated granulomatous interstitial nephritis. Crohn disease needs to be in the differential diagnosis of granulomatous interstitial nephritis and can be a manifestation of drug allergy or the Crohn disease itself.

Renal insufficiency in IBD--prevalence and possible pathogenetic aspects

BACKGROUND AND AIMS

Extraintestinal manifestations of parenchymatous organs like kidney are rarely noticed in Inflammatory Bowel Disease (IBD). The aim of this study was to investigate the prevalence of renal insufficiency (RI) in IBD and look for potential causative factors and pathogenetic aspects.

METHODS

The study consists of two parts; the first determined the prevalence of RI in IBD and the second possible causative factors. For the first part all patients with IBD who had been investigated at our institution in the period from March 2006 to December 2007 were included. For the second part 25 IBD patients with RI were matched with 50 IBD patients without RI. To determine causative factors several gastroenterologic and renal parameters were compared between these two groups.

RESULTS

Eleven out of 775 patients with IBD had RI, all of them suffering from Crohn's disease (CD). This led to a prevalence of 1.99% for patients with CD and of 0% for patients with ulcerative colitis (UC). Concerning IBD risk factors only duration of disease (p=0.002) and length of resected small bowel (p=0.004) had a significant impact. Two nephrologic parameters, recurrent urolithiasis and the number of interventions due to kidney stones, were risk factors for the development of RI (p=0.03).

CONCLUSIONS

RI is a rare (2%) but relevant complication in CD, not found in UC. Extensive small bowel resection and recurrent urolithiasis seem to be the major causative factors.

Extraintestinal manifestations and complications in IBD

More than one-third of patients with IBD are affected by extraintestinal manifestations or extraintestinal complications beyond the intestinal manifestation of the disease. The most common manifestations include arthropathies, mucocutaneous and ophthalmological manifestations, as well as conditions affecting the hepatobiliary system, both in Crohn's disease and ulcerative colitis. However, less frequent manifestations, such as pulmonary or neurological manifestations, should also be considered in patients with IBD. Several extraintestinal manifestations follow the course of the underlying intestinal activity, whereas others are independent from the intestinal inflammation. Extraintestinal complications such as iron-deficiency anaemia and osteoporosis are consequences of the intestinal disease or of disease-specific treatment. As extraintestinal manifestations and complications strongly influence quality of life, and to avoid severe complications, adequate treatment is mandatory in affected patients. We provide a comprehensive overview of different extraintestinal manifestations and complications, including their management, in patients with IBD.

Frequency and risk factors of renal insufficiency in inflammatory bowel disease inpatients

BACKGROUND

Renal involvement in patients with inflammatory bowel disease (IBD) has been well documented. However, there was a paucity of data on the frequency of renal insufficiency and its risk factors in this patient population. The aim of the study was to determine the frequency and factors associated with renal insufficiency within IBD inpatients.

METHODS

This case-control study was conducted on both Crohn's disease and ulcerative colitis inpatients in our tertiary care center from 2009 to 2010. Patients were identified as having renal insufficiency by the criterion of glomerular filtration rate < 60 mL/min/1.73 m. The glomerular filtration rate was further assessed against normal reference ranges. Risk factors for renal insufficiency were evaluated by univariable and multivariable analyses.

RESULTS

A total of 251 eligible patients were included. The frequency of renal insufficiency was 15.9% (95% confidence interval: 11.4-20.5), with 40 patients having a glomerular filtration rate <60 mL/min/1.73 m. Univariable analysis demonstrated several possible risk factors, including older age at admission (42.0 ± 16.2 years versus 57.6 ± 13.3 years, P < 0.001), and a longer median duration of IBD (9.0 years [interquartile range: 3.5-20.0] versus 25.0 years [interquartile range: 15.0-36.0], P < 0.001). The multivariable logistic analysis demonstrated that for every 5-year increase in age at the time of admission, the likelihood of having renal insufficiency increased by 30%.

CONCLUSION

Acute or chronic renal sufficiency in IBD inpatients was common, especially in elderly. Acute renal insufficiency can be medically reversed if properly treated. We recommend that renal function be closely monitored in IBD inpatients.

Diagnosis and therapeutic management of extra-intestinal manifestations of inflammatory bowel disease

Extra-intestinal manifestations (EIMs) are reported frequently in patients with inflammatory bowel disease (IBD) and may be diagnosed before, concurrently or after the diagnosis of IBD. EIMs in IBD may be classified based on their association with IBD disease activity. The first group has a direct relationship with the activity of the bowel disease and includes pauciarticular arthritis, oral aphthous ulcers, erythema nodosum and episcleritis. The second group of EIMs appears to follow an independent course from the underlying bowel disease activity and include ankylosing spondylitis and uveitis. The third group includes EIMs that may or may not be related to intestinal inflammation, such as pyoderma gangrenosum and probably primary sclerosing cholangitis (PSC). Genetic susceptibility, aberrant self-recognition and immunopathogenic autoantibodies against organ-specific cellular antigens shared by the colon and extra-colonic organs may contribute to the pathogenesis and development of these EIMs. The use of biological agents in the IBD armamentarium has expanded the treatment options for some of the disabling EIMs and these agents form the cornerstone in managing most of the disabling EIMs. PSC is one of the most common hepatobiliary manifestations associated with IBD in which no clear treatment options exist other than endoscopic therapy and liver transplantation. Future research targeting the pathogenesis, early diagnosis and treatment of these EIMs is required.

Diagnosis and therapeutic management of extra-intestinal manifestations of inflammatory bowel disease

Extra-intestinal manifestations (EIMs) are reported frequently in patients with inflammatory bowel disease (IBD) and may be diagnosed before, concurrently or after the diagnosis of IBD. EIMs in IBD may be classified based on their association with IBD disease activity. The first group has a direct relationship with the activity of the bowel disease and includes pauciarticular arthritis, oral aphthous ulcers, erythema nodosum and episcleritis. The second group of EIMs appears to follow an independent course from the underlying bowel disease activity and include ankylosing spondylitis and uveitis. The third group includes EIMs that may or may not be related to intestinal inflammation, such as pyoderma gangrenosum and probably primary sclerosing cholangitis (PSC). Genetic susceptibility, aberrant self-recognition and immunopathogenic autoantibodies against organ-specific cellular antigens shared by the colon and extra-colonic organs may contribute to the pathogenesis and development of these EIMs. The use of biological agents in the IBD armamentarium has expanded the treatment options for some of the disabling EIMs and these agents form the cornerstone in managing most of the disabling EIMs. PSC is one of the most common hepatobiliary manifestations associated with IBD in which no clear treatment options exist other than endoscopic therapy and liver transplantation. Future research targeting the pathogenesis, early diagnosis and treatment of these EIMs is required.

Acute tubulointerstitial nephritis

Acute tubulointerstitial nephritis (TIN) is a frequent cause of acute renal failure, characterised by the presence of inflammatory cell infiltrate in the interstitium of the kidney. Immuno-allergic reaction to certain medications, mainly non-steroidal anti-inflammatory drugs and antibiotics are by far the most important etiology for TIN today, but other situations such as infections, toxins, and vasculitis are known to induce TIN. Incidence of TIN is increasing, probably due to prescription habits and NSAID overuse, representing 3-7% of acute kidney injury in biopsies in children. Avoidance of the causal substance and rapid steroid therapy are hallmarks for patient care, but spontaneous initial recovery is very frequent and the general prognosis seems satisfactory. However, development of chronic TIN, without response to steroid or other immunosuppressive treatment, is possible. As the largest part of TIN is secondary to certain drugs, clear indications in particular for NSAID or antibiotics should be respected to reduce the number of TIN cases.

Neutrophil gelatinase-associated lipocalin (NGAL) in inflammatory bowel disease: association with pathophysiology of inflammation, established markers, and disease activity

BACKGROUND

Neutrophil gelatinase-associated lipocalin (NGAL) is a multi-potent 25-kDa protein mainly secreted by neutrophils. In inflammatory bowel disease (IBD), overexpression of NGAL in colon epithelium has been previously shown. This is the first study analyzing serum and urinary NGAL levels in IBD patients, with regard to specific characteristics of patients and disease.

METHODS

Serum and urinary NGAL levels were determined in 181 patients with IBD, 93 with ulcerative colitis (UC), and 88 with Crohn's disease (CD), 82 healthy controls (HC), and 41 patients with irritable bowel syndrome (IBS).

RESULTS

Serum NGAL levels were elevated in IBD patients (88.19 ± 40.75 ng/mL) compared with either HC (60.06 ± 24.18 ng/mL) or IBS patients (60.80 ± 20.30 ng/mL), P < 0.0001. No significant difference was shown between UC (86.62 ± 35.40 ng/mL) and CD (89.92 ± 46.05 ng/mL). Significantly higher levels of serum NGAL were observed in patients with active (120.1 ± 38.46) versus inactive IBD (61.58 ± 15.98), P < 0.0001. Serum NGAL displayed a strong ability to distinguish active IBD from inactive disease, healthy controls, or IBS patients with a sensitivity of 100, 95, and 95% and a specificity of 68, 83, and 79%, respectively, performing better than erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in the assessment of disease activity in both UC and CD. Urinary NGAL levels showed neither significant difference among patients and controls nor correlation with disease activity.

CONCLUSIONS

Serum NGAL is elevated particularly in active IBD and correlates with established markers of inflammation and disease activity, implicating its role in the pathophysiology of IBD.

Drug-induced nephrotoxicity in inflammatory bowel disease

Conservative management of inflammatory bowel disease (IBD) is based on a combination of drugs, including aminosalicylates (ASAs), steroids, antibiotics, immunosuppressives and biologic agents. Although various side effects have been related to treatment regimens, drug-induced nephrotoxicity is rather uncommon. Furthermore, it is often underestimated since renal function deterioration may be attributed to the underlying disease. The nephrotoxicity of ASAs and cyclosporine A seems well established, but recent data have suggested a possible role of biologic agents such as infliximab and adalimubab in renal impairment. The aim of this review is to summarize the nephrotoxic effects of medical treatment as well as to express possible caveats in the administration of novel agents in IBD.