Late onset interstitial nephritis associated with mesalazine treatment

5-ASA induced interstitial nephritis in patients with inflammatory bowel disease: a systematic review

Background

Acute interstitial nephritis (AIN) is an important cause of kidney injury accounting for up to 27% of unexplained renal impairment. In up to 70% of cases, drugs, including aminosalicylates, are reported as the underlying cause. Following two recent paediatric cases of suspected mesalazine induced AIN within our own department, we performed a systematic review of the literature to address the following question: In patients with inflammatory bowel disease (IBD), is interstitial nephritis associated with 5-aminosalicylate (5-ASA) treatment? Our primary objective was to identify the number of cases reported in the literature of biopsy-proven 5-ASA induced interstitial nephritis, in children and adults with IBD. We also aimed to identify which variables influence the onset, severity and recovery of 5-ASA interstitial nephritis.

Methods

Embase and PubMed databases were searched from inception to 07/10/20. Search terms had three main themes: “inflammatory bowel disease”, “interstitial nephritis” and “aminosalicylates”. Studies were included if they reported an outcome of AIN, confirmed on biopsy, suspected to be secondary to a 5-ASA drug in those with IBD. A narrative synthesis was performed.

Results

Forty-one case reports were identified. Mesalazine was the most frequently reported aminosalicylate associated with AIN (95%). The median duration of treatment before AIN was diagnosed was 2.3 years (Interquartile Range (IQR) 12–48 months). The median rise in creatinine was 3.3 times the baseline measurement (IQR 2.5–5.5). Aminosalicylate withdrawal and steroids were the most frequently used treatments. Despite treatment, 15% of patients developed end-stage renal failure.

Conclusions

AIN is a serious adverse drug reaction associated with aminosalicylates, with mesalazine accounting for most reports. The current guidance of annual monitoring of renal function may not be sufficient to identify cases early. Given the severity of AIN and reports in the literature that early treatment with steroids may be beneficial, we would recommend at least 6 monthly monitoring of renal function.

PROSPERO registration number CRD42020205387.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40001-022-00687-y.

Colitis and Crohn's Foundation (India) consensus statements on use of 5-aminosalicylic acid in inflammatory bowel disease

Despite several recent advances in therapy in inflammatory bowel disease (IBD), 5-aminosalicylic acid (5-ASA) therapy has retained its place especially in ulcerative colitis. This consensus on 5-ASA is obtained through a modified Delphi process, and includes guiding statements and recommendations based on literature evidence (randomized trials, and observational studies), clinical practice, and expert opinion on use of 5-ASA in IBD by Indian gastroenterologists. The aim is to aid practitioners in selecting appropriate treatment strategies and facilitate optimal use of 5-ASA in patients with IBD.

No increased risk of nephrotoxicity associated with 5-aminosalicylic acid in IBD: a population-based cohort and nested case-control study

BACKGROUND

There is conflicting evidence about nephrotoxicity risk associated with 5-aminosalicylates for treatment of IBD.

AIMS

To determine population-based temporal trends for 5-aminosalicylates and estimated risk of nephrotoxicity associated with 5-aminosalicylate use for ulcerative colitis (UC) and Crohn's disease (CD).

METHODS

Retrospective cohort and nested case-control study, using the Health Improvement Network primary care database linked to hospital discharge coding for patients in England, 1996-2017. Nephrotoxicity risk analysis was a first recorded renal impairment diagnosis adjusted for key variables and was assessed between 2008 and 2017.

RESULTS

A total of 35 601 patients with prevalent UC or CD were included. The proportion of patients prescribed 5-aminosalicylates fell from 83% in 1996-1999 to 71% in 2012-2015 for UC patients and 64% to 45% for CD patients. Thirty per cent of patients had prolonged 5-aminosalicylate use. Between 2008 and 2017, the incident rate of nephrotoxicity was similar and stable for UC (12.6/1000 person-years) and CD (10.9/1000 person-years) patients. Multivariate analysis showed no evidence for association between current prescription of 5-aminosalicylate and nephrotoxicity in UC or CD patients, comparing ≤ 30 days prescription prior to index vs 31-≤180 days. However, active disease, disease duration, concomitant cardiovascular disease or diabetes and nephrotoxic drug use were independently associated with development of nephrotoxicity in UC and CD.

CONCLUSIONS

Despite the paucity of evidence for their benefit, 5-aminosalicylates were prescribed to approximately half of CD patients (30% prolonged therapy). Nephrotoxicity was rare in this patient cohort, and was not associated with 5-aminosalicylate use, but rather with disease status, comorbidity and use of nephrotoxic drugs.

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.

Chronic tubulointerstitial nephritis induced by 5-aminosalicylate in an ulcerative colitis patient: a rare but serious adverse event

The 5-aminosalicylate is widely prescribed in inflammatory bowel disease patients. Its potential for renal damage has been seldom described. We report a case of a 23-year-old man who started 5-aminosalicylate after being diagnosed with ulcerative colitis. One year after, a significant decline on his creatinine clearance was noted, however, at that time, he was on an acute flare of his bowel disease and the 5-aminosalicylate dose was increased. Six months later, his renal function kept worsening and, on drug-induced toxicity suspicion, 5-aminosalicylate was halted and a kidney biopsy demonstrated a chronic tubulointerstitial nephritis. Steroids and azathioprine were started leading to partial recovery and stabilisation of his renal function. Physicians who prescribe 5-aminosalicylate to patients with inflammatory bowel disease should be aware of this adverse event.

Do gastroenterologists monitor their patients taking 5-amino-salicylates following initiation of treatment

BACKGROUND

5-Amino salicylate (5-ASA) medications may rarely be associated with a significant decline in renal function and interstitial nephritis. British Society of Gastroenterology guidelines advise regular renal function monitoring for patients taking these drugs.

AIM

To assess whether gastroenterologists in Kent were following best practice guidelines regarding the monitoring of their patients on 5-ASA therapy.

METHODS

Using longitudinal community and regional pathology databases for the Kent population, our renal unit regularly screens a total population of 300 000 for evidence of renal disease. The data extracted are analysed using an automated computerised system to identify patients requiring intervention for kidney disease. All patients taking 5-ASA medication were identified from a population of 300 000. The pathology database was studied to identify the patients on 5-ASA treatment and whether they had had renal function tests.

RESULTS

800 adult patients were identified taking 5-ASA therapy. 612 patients received 5-ASAs for 3 months or more, and these were included in the final analysis. 293 patients had no renal function checks while on treatment. 79 patients had renal function tests less than once every 4 years and 36 patients once every 2-4 years. 204 patients had renal function measurements in 50% or more of years of treatment, of whom 116 were checked every year. Some patients were started on treatment with abnormal results at baseline and some with identified kidney disease continued on their 5-ASAs.

CONCLUSIONS

The majority of patients receiving 5-ASA compounds do not have regular renal function monitoring. Clinicians are failing to follow best practice guidelines.

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.

Renal manifestations and complications of inflammatory bowel disease

Renal manifestations and complications are not rare in patients with inflammatory bowel disease (IBD) and may present as nephrolithiasis, amyloidosis, tubulointerstitial nephritis, and glomerulonephritis. Symptoms of renal impairment are not always specific and since the underlying bowel disease is preponderant, renal function deterioration may be underestimated. Additionally, medical treatment of patients with IBD such as aminosalicylates, cyclosporine, and tumor necrosis factor-α inhibitors can cause renal complications, although direct correlation to bowel disease is not always clear. The well-documented renal manifestations and complications of IBD, as well as the possible renal side effects of new drugs, emphasize the need for periodic evaluation of renal function. New markers of renal function may facilitate early diagnosis and unravel the complex mechanisms responsible for kidney damage. The purpose of this review is to summarize the renal manifestations and complications as well as the markers of renal function utilized in IBD, attempting to shed more light on the pathophysiology of renal damage in IBD.

Oxidative stress as a mechanism underlying sulfasalazine-induced toxicity

INTRODUCTION

Sulfasalazine (SASP) is a drug commonly used in the treatment of inflammatory bowel diseases (IBD) such as ulcerative colitis and Crohn's disease (CD) and rheumatoid arthritis (RA). A high incidence of side effects limits therapy with this drug. Getting a wider knowledge of drug pharmacology, indications and side effects is essential to ensure the best possible clinical care, minimizing toxicity and inappropriate use.

AREAS COVERED

This paper gives an overview of recent research about SASP and its main adverse effects, highlighting the mechanisms underlying them. To give an overview and comment on the data available so far on this topic, relevant literature was identified using a PubMed search of articles published up to December 2009. Search terms included: 'sulfasalazine', 'oxidative stress, 'renal effects', 'hepatotoxicity' and 'male fertility'. Original papers were reviewed and relevant citations from these articles were also considered.

EXPERT OPINION

Although SASP and 5-aminosalicylic acid also scavenge ROS, which may account for some of their anti-inflammatory properties, the reaction with ROS may also generate toxic free radicals; hence, the ability of other antioxidants to suppress the toxicity of SASP in vivo. Further investigations, particularly about SASP mechanism, are still needed.

Acute interstitial nephritis associated with ulcerative colitis

Although drugs used in inflammatory bowel diseases (IBD) cause renal injury, glomerulopathies may also accompany IBD. We report a case with the rare association of ulcerative colitis (UC) and acute progressive interstitial nephritis. Although the kidney is acknowledged as a target organ for injury as a result of drug nephrotoxicity, our findings lend support to the novel recognition that the deranged autoimmune system emerging in UC causes interstitial nephritis as an extraintestinal manifestation. Overt renal failure due to interstitial nephritis has rarely been reported in UC patients. The case presented here therefore provides novel information on UC-associated nephropathy.

Update on the role of modified release mesalamine in the management of ulcerative colitis and Crohn's disease

5-aminosalicyclates (5-ASA) remain a key first-line therapy for patients with ulcerative colitis (UC). A range of 5-ASA preparations is available and Eudragit-S^® coated modified release formulations of mesalamine, such as Asacol^®, remain among the most popular choices. We here review the current understanding of the mechanism of action of 5-ASA in inflammatory bowel disease. We evaluate evidence supporting the efficacy and safety of modified release mesalamine for both induction and remission maintenance in UC, including a review of the data from the recent ASCEND studies. We also examine the controversial issue of the role of mesalamine in treatment of Crohn’s disease (CD) and highlight data supporting its use following surgically induced remission of CD. Evidence supporting the use of mesalamine as prophylaxis for colorectal cancer and dysplasia will be considered. Finally, recent developments in our understanding of how to use modified release mesalamine in a safe and cost-effective manner are evaluated, including discussion of the importance of studying patient non-adherence as a key component of future studies in this area.

Effect of 5-aminosalicylates on renal function in patients with inflammatory bowel disease: 4-year follow-up study

OBJECTIVE

Nephrotoxicity has been described in some patients with inflammatory bowel disease (IBD) treated with 5-aminosalicylates (5-ASA). Our aim was to conduct a retrospective study of IBD patients, both with and without 5-ASA treatment, who underwent regular evaluation of renal function over a 4-year period.

METHODS

Serum creatinine was measured before the start of 5-ASA therapy, and thereafter yearly up to 4 years. Creatinine clearance (Cl(Cr)) was estimated from serum creatinine (Cockroft and Gault formula). The influence of 5-ASA treatment on renal function was assessed by univariate and multivariate analysis.

RESULTS

A total of 150 IBD patients (ulcerative colitis in 45%, Crohn's disease in 55%) were included. Sixty-two patients were receiving 5-ASAs (95% coated mesalazine, mean dose 1.9 +/- 0.8 g/day). Both serum creatinine levels and ClCr were similar in patients with and without 5-ASA treatment, and remained stable throughout the 4-year follow-up in patients taking 5-ASAs. In the multivariate analysis, 5-ASA treatment (or its dose) was not correlated with serum creatinine levels or Cl(Cr). No interstitial nephritis was reported during follow-up.

CONCLUSION

5-ASA-related renal disease was not found in our series, suggesting that the occurrence of renal impairment in IBD patients receiving these drugs is exceptional. Our results do not support the recommendation of serum creatinine monitoring in patients receiving 5-ASA treatment.

Renal effects of long-term treatment with 5-aminosalicylic acid

BACKGROUND

A number of case reports link the use of 5-aminosalicylic acid (5-ASA) to interstitial nephritis in patients with inflammatory bowel disease (IBD).

OBJECTIVE

To investigate whether the long-term use of 5-ASA has harmful effects on renal function in patients with IBD.

METHODS

A retrospective analysis of 171 consecutive outpatients with Crohn's disease or ulcerative colitis was conducted. Serum creatinine levels and body weight were measured before and after treatment to calculate the creatinine clearance (CrCl) rate.

RESULTS

In 171 patients (93 women, 78 men), the mean (+/- SD) dose of 5-ASA was 3.65+/-0.85 g/day with a cumulative dose of 11+/-7.7 kg over an interval of 8.4+/-5.9 years. Serum creatinine concentrations increased from 76.8 micromol/L to 88.7 micromol/L (n=171; P<0.0001) and the CrCl rate fell significantly from 104.6 mL/min to 93.1 mL/min (n=81; P<0.0001). There was one case of interstitial nephritis reported. Treatment groups included mesalamine (74.3%), sulfasalazine (15.2%) and combination (sulfalsalazine/mesalamine [10.5%]) with treatment durations of 7.2+/-4.5, 12.3+/-8.7 and 11.2+/-6.7 years, respectively. The duration of treatment was the most important covariate for change in CrCl and when analyzed by treatment group, those treated with sulfasazine had a strong correlation (r=-0.54, P=0.0145), while nonsignificant in the mesalamine group (r=0.06, P=0.7017). The decline in CrCl was negatively correlated with the pretreatment CrCl rate (r=-0.34; P=0.0024) and positively correlated with the mean daily dose of 5-ASA (r=0.32; P=0.0034).

CONCLUSION

The present study is the first to demonstrate a significant dose- and treatment duration-dependant decline in CrCl. The risks need to be further evaluated because 5-ASA is widely used for long-term maintenance therapy in patients with IBD.

5-Aminosalicylates and renal function in inflammatory bowel disease: a systematic review

Nephrotoxicity has been described in some patients with inflammatory bowel disease (IBD) treated with 5-aminosalicylic acid (5-ASA). Studies with 5-ASA treatment in which serum creatinine or creatinine clearance was measured regularly show that nephrotoxicity is exceptional (mean rate of only 0.26% per patient-year). There have been several case reports, including 46 patients, of renal disease associated with 5-ASA treatment in patients with IBD. 5-ASA treatment-related nephrotoxicity is reported most often within the first 12 months, but also delayed presentation after several years has been shown. The absence of a clear relationship between 5-ASA dose and the risk of nephrotoxicity suggests that this complication is idiosyncratic rather than dose-related. Most of the patients with renal disease associated with 5-ASA treatment suffered interstitial nephritis, with symptoms and signs being nonspecific, which may delay detection for many months. The nephrotoxicity potential of mesalazine and sulfasalazine seems to be similar. The risk with different oral preparations of 5-ASA is probably too small to influence the choice of agent. Mesalazine should be withdrawn when renal impairment manifests in a patient with IBD; if this does not result in a fall in serum creatinine, then renal biopsy should be considered. A trial of high-dose steroid may be recommended in patients whose renal function does not respond to drug withdrawal. The optimal monitoring schedule of serum creatinine in patients receiving 5-ASA treatment remains to be established, as there is no evidence to date that either the test, or the frequency of testing, improves patient outcomes.

5-Aminosalicylates and effects on renal function in patients with Crohn's disease

BACKGROUND

Case reports concerning irreversible renal failure caused by 5-aminosalicylates (5-ASA) have been published. The aim of this study was to investigate the effect of long-term use of 5-ASA on renal function in patients with Crohn's disease (CD).

METHODS

This was a retrospective survey in 200 consecutive outpatients with CD. Endogenous creatinine clearance (ECC) was estimated from serum creatinine with the Cockroft and Gault formula. The first ECC was chosen close to the start of 5-ASA and the second was the most recent ECC available.

RESULTS

In 153 patients (59 men and 94 women), sufficient data were available for analysis. The interval between ECCs was 11 years, with a mean exposure to 5-ASA of 8.6 years. The cumulative dose of 5-ASA amounted to 9 kg. The ECC declined 0.3 +/- 5 mL/min/yr (from 100 +/- 25 to 92 +/- 28 mL/min; P < 0.01). In a multiple linear regression model, duration of the interval was a significant predictor for change in ECC (P < 0.0001), but cumulative dose of 5-ASA was not predictive (P = 0.30). No interstitial nephritis was reported, and in the 8 patients with the largest decline in ECC, comorbidity causing renal function impairment was present.

CONCLUSIONS

The mean decline in ECC of 0.3 mL/min/yr in patients with CD does not exceed the decline expected from physiologic aging. Furthermore, the cumulative dose of 5-ASA was not a predictor for change in renal function. However, as interstitial nephritis caused by 5-ASA may rarely occur, we still advocate measurements of serum creatinine before and during treatment.

The clustering of other chronic inflammatory diseases in inflammatory bowel disease: a population-based study

BACKGROUND & AIMS

We aimed to discern the relative risk for several chronic inflammatory conditions in patients with ulcerative colitis (UC) and Crohn's disease.

METHODS

We used the population-based University of Manitoba IBD Database that includes longitudinal files on all patients from all health system contacts identified by International Classification of Diseases, 9th revision, Clinical Modification codes for visit diagnosis. From the provincial database we extracted a control cohort matching the IBD patients 10:1 by age, sex, and geography. We considered a potential comorbid disease to be present if the patient had 5 or more health system contacts for that diagnosis. The comorbid disease period prevalence was analyzed separately for patients with UC and Crohn's disease and a prevalence ratio was calculated comparing the IBD populations with the matched cohort.

RESULTS

There were 8072 cases of IBD from 1984 to 2003, including UC (n = 3879) and Crohn's disease (n = 4193). There was a mean of approximately 16 person-years of coverage for both patients and control patients. Both UC and Crohn's disease patients had a significantly greater likelihood of having arthritis, asthma, bronchitis, psoriasis, and pericarditis than population controls. An increased risk for chronic renal disease and multiple sclerosis was noted in UC but not Crohn's disease patients. The most common nonintestinal comorbidities identified were arthritis and asthma.

CONCLUSIONS

The finding of asthma as the most common comorbidity increased in Crohn's disease patients compared with the general population is novel. These may be diseases with common causes or complications of one disease that lead to the presentation with another. Studies such as this should encourage further research into the common triggers in the organ systems that lead to autoimmune diseases.

Experience of 5-aminosalicylate nephrotoxicity in the United Kingdom

AIM

To study 5-aminosalicylate nephrotoxicity in patients with inflammatory bowel disease in the UK.

METHODS

A detailed postal questionnaire was sent to all 1298 names in the British Society of Gastroenterology database and 290 consultant members of the Renal Association. The British Society of Gastroenterology reported new cases monthly, the Renal Association 6 monthly. Results were expressed as estimated glomerular filtration rate.

RESULTS

Retrospective study: cases--British Society of Gastroenterology:Renal Association 202:87, aged 15-76 years. Median peak (range) creatinine (British Society of Gastroenterology:Renal Association) - 300:301 (78-1200) micromol/L. Prospective study - 59 cases, median age 52 years (M:F ratio: 47:12). Median pre-treatment estimated glomerular filtration rate: 76.9 (123.9-39), at diagnosis 28.4 (80.5-3.6, creatinine range: 92-1361 micromol/L), recovery 46.8 [111.2-end stage renal failure] mL/min/1.73 m2. Recovery of renal function was significantly improved for patients treated for < 12 months [n = 10, median recovery estimated glomerular filtration rate 70.5 (92-26.9) vs. > 12 months 38.4 (111.2-end stage renal failure) mL/min/1.73 m2, P = 0.028].

CONCLUSIONS

Regular monitoring of renal function may allow earlier detection of nephrotoxicity, particularly during the first year of therapy. Based on an inflammatory bowel disease prevalence in the United Kingdom of 412 x 10(5) with about 50% on treatment, we estimate that the incidence of clinical nephrotoxicity in patients taking 5-aminosalicylate therapy is approximately one in 4000 patients/year.

Acute interstitial nephritis due to mesalazine. Case Report

A case of mesalazine-induced acute interstitial nephritis (AIN) in a 41-year-old patient with ulcerative colitis (UC) is reported here. Clinical symptoms such as fever and arthralgia, and laboratory findings such as eosinophilia and renal failure suggested AIN, which was confirmed by biopsy. With withdrawal of mesalazine and intravenous methylprednisolone the patient's renal function was recovered. It is observed that early discontinuation of mesalazine is associated with amelioration of interstitial nephritis in most patients, so the recommendation is that patients receiving mesalazine should undergo routine monitoring of renal function. Delayed diagnosis may lead to permanent renal function impairment.

Interstitial nephritis from mesalazine: case report and literature review

We report a new case of biopsy-confirmed mesalazine-induced interstitial nephritis in an 18-year-old male with ulcerative colitis. His renal function improved with drug discontinuation and corticosteroid treatment. An English literature review revealed an additional 22 cases of this complication that, taken together, showed (1) a male predominance, (2) an absence of specific symptoms or findings on urinalysis, (3) a 61% frequency of residual chronic renal insufficiency with 13% of patients developing end-stage renal disease, and (4) an apparent favorable response to steroid therapy. We conclude that patients receiving 5-aminosalicylates should be routinely monitored with serum creatinine measurements to prevent this uncommon but potentially serious adverse drug reaction.

Role of mesalazine in acute and long-term treatment of ulcerative colitis and its complications

BACKGROUND

Sulfasalazine, consisting of 5-aminosalicylic acid bound to sulfapyridine by a diazo bond, was first used for treatment of ulcerative colitis in the early 1940s and later found effective in placebo-controlled trials for acute disease and for long-term maintenance of remission. Later studies found that the active moiety is 5-ASA (mesalazine, mesalamine) and the sulfapyridine moiety acts as a carrier molecule but causes many of the symptomatic adverse reactions.

METHODS

Review of the literature.

RESULTS

The finding that 5-ASA in the active motility led to the development of mesalazine prodrugs, olsalazine (Dipentum) and balsalazide (Colazide, Colazal), and targeted release mesalazine preparations, such as Asacol, Pentasa, and Salofalk, as well as enemas and suppository preparations for distal disease. Most patients with adverse effects from sulfasalazine will tolerate mesalazine. Mesalazine has been shown equivalent or superior to sulfasalazine, and superior to placebo, with a dose-response benefit, in inducing remission of acute disease. and comparable to sulfasalazine and superior to placebo for long-term maintenance of remission. Better tolerance of mesalazine and the ability to use higher doses favor its use in patients intolerant of sulfasalazine and in patients failing to respond to usual doses of sulfasalazine. Adverse effects from mesalazine are uncommon, but include idiosyncratic worsening of the colitis symptoms and renal toxicity. Mesalazine is safe to use during pregnancy and for nursing mothers. As maintenance therapy, mesalazine may reduce the risk of developing colorectal carcinoma.

CONCLUSION

Mesalazine represents effective and well-tolerated first-line therapy for mildly to moderately acute disease as well as for the long-term maintenance treatment in the patient with ulcerative colitis.

Osteoporosis and other complications of inflammatory bowel disease

Osteoporosis has received increasing attention as a potential complication of inflammatory bowel disease (IBD). The first population-based data on incidence of fractures in an IBD population were published this past year. The incidence of fractures was one per 100 patient years. Compared with the general population, the fracture rate was increased; however, the relative risk was 1.4 and, therefore, not as high as might be expected from the myriad of studies reporting high rates of osteopenia measured by dual energy x-ray absorptiometry (DXA). Another area receiving increasing attention is that of the enhanced risk of venous thrombosis in patients with IBD. The first population-based incidence rates of venous thrombosis in IBD were also published this past year and showed that IBD patients are affected by venous thrombosis at a rate of approximately one per 200 patient years. The relative risk for venous thrombosis compared with the general population was 3.5. Several studies have reported on associated risk markers or genetic clotting abnormalities, but no clear paradigm has emerged to account for those patients who will suffer a clot. Finally, the first North American population-based study was published, quantifying the prevalence rates of extraintestinal manifestations in patients with IBD for at least 10 years. Some gender- and disease-specific findings emerged. This study found that iritis and uveitis were more common in female patients with ulcerative colitis (3.2%), primary sclerosing cholangitis (PSC) was most common in male patients with ulcerative colitis (3%), ankylosing spondylitis was most common in male patients with Crohn disease (2.7%), and erythema nodosum was most likely to occur in female patients with Crohn disease (1.9%).

Renal tubular injury is present in acute inflammatory bowel disease prior to the introduction of drug therapy

BACKGROUND

5-aminosalicylic acid (5-ASA) has been associated with renal complications in inflammatory bowel disease. Renal function is typically monitored using serum creatinine; however, significant disease may predate increases in creatinine.

AIMS

To identify whether markers of early renal disease (urinary albumin, alpha-1-microglobulin [alpha-1-M] and N-acetyl-beta-D-glucosaminidase [NAG], and serum cystatin C) are useful in the assessment of renal function in inflammatory bowel disease patients receiving 5-ASA.

METHODS

Twenty-one patients with a new diagnosis of inflammatory bowel disease were investigated. Samples were taken at diagnosis, and at 3-monthly intervals after the commencement of 5-ASA, for 1 year.

RESULTS

Mean creatinine clearance was 100 mL/min and did not change following treatment. Inflammatory bowel disease was not associated with albuminuria. Urinary N-acetyl-beta-D-glucosaminidase and alpha-1-microglobulin at diagnosis were increased in 10 (48%) and 11 (52%) patients, respectively: treatment was not associated with consistent changes in urinary protein excretion. There was a significant correlation between cystatin C and creatinine clearance both at diagnosis (r=-0.533, P=0.0275) and combining the initial and follow-up data (r=-0.601, P < 0.01), but not between creatinine and creatinine clearance (P > 0.05).

CONCLUSIONS

Tubular proteinuria is an extra-intestinal manifestation of inflammatory bowel disease irrespective of 5-ASA treatment. Tubular proteins are not useful predictors of an adverse renal response to 5-ASA. Serum cystatin C may be an improved marker of glomerular filtration rate in this setting.

Minimal renal dysfunction in inflammatory bowel disease is related to disease activity but not to 5-ASA use

BACKGROUND

Conflicting data exist about proteinuria in inflammatory bowel diseases. It is still unclear whether the occurrence of proteinuria in inflammatory bowel disease patients is an extra-intestinal manifestation of disease or the result of adverse effects to medication, especially to aminosalicylates (ASA).

METHODS

A total of 95 patients (51 with Crohn's disease and 44 with ulcerative colitis) were enrolled in the study. Disease activity was assessed by Crohn's Disease Activity Index (CDAI) or the Truelove index, respectively. Urine was collected over 24 h and protein excretion of specific marker proteins for tubular (alpha 1-microglobulin-alpha 1-MG) and glomerular (albumin-Alb, Immunoglobulin G-IgG) dysfunction was measured using a highly sensitive immunoluminometric assay.

RESULTS

Out of 51 Crohn's disease patients, 20 showed elevated urinary alpha 1-MG. The amount of alpha 1-MGuria was strongly correlated to the CDAI (r=0.6, P < 0.001). Only four Crohn's disease patients showed slightly elevated values for glomerular proteins in urine. Similar results were obtained for ulcerative colitis: whereas only two ulcerative colitis patients showed albuminuria, tubular proteinuria was detected in 28 out of 44 ulcerative colitis patients. Proteinuria was strongly dependent on disease activity (P < 0.01) but was not related to ASA treatment.

CONCLUSIONS

Proteinuria of tubular marker proteins occurs in the majority of inflammatory bowel disease patients and is related to disease activity rather than to ASA treatment. Tubular proteinuria seems to reflect a renal extra-intestinal manifestation of inflammatory bowel disease and may serve as a new relevant marker of disease activity.

Interstitial nephritis in patients with inflammatory bowel disease treated with mesalamine

Mesalamines are slow-release formulations of 5-aminosalicylic acid (5-ASA) and are effective as primary treatment and maintenance therapy in inflammatory bowel disease. Interstitial nephritis is a recognized side effect. We report two cases of biopsy-confirmed interstitial nephritis in patients being treated with 5-ASA. Both had a trial of steroid therapy. One patient had partial recovery of renal function but the other patient was in chronic renal failure and likely was approaching the need for dialysis. Interstitial nephritis is an under-recognized complication of 5-ASA therapy. Early identification and withdrawal of this drug can lead to a partial or complete reversal of renal dysfunction.

Review article: interstitial nephritis associated with the use of mesalazine in inflammatory bowel disease

5-Aminosalicylic acid (5-ASA) has replaced sulphasalazine as first line therapy for mild to moderately active inflammatory bowel disease and is widely used. A number of reports have linked oral 5-ASA therapy to chronic tubulo-interstitial nephritis and this relationship is now well established. Despite increasing recognition of the potential for this serious adverse event, guidelines for monitoring renal function in patients prescribed 5-ASA preparations are not widely employed. Whilst the incidence of this adverse event in the population of patients with inflammatory bowel disease treated with mesalazine is low, the morbidity in an affected individual is high with some cases progressing to end-stage renal disease. Routine monitoring of renal function is simple and inexpensive and could prevent this outcome. Based on the available data, serum creatinine should be estimated prior to commencing treatment, monthly for the first 3 months, 3-monthly for the next 9 months, 6-monthly thereafter and annually after 5 years of treatment.

Oral delayed-release mesalazine: a review of its use in ulcerative colitis and Crohn's disease

Oral delayed-release mesalazine is an enteric-coated formulation which releases mesalazine in the terminal ileum and colon. Up to 74% of patients with mild to moderately active ulcerative colitis experience endoscopic or symptomatic improvement (including remission) or both when treated with oral delayed-release mesalazine 2.4 to 4.8 g/day. There is a trend towards a better response in patients receiving higher daily dosages of oral delayed-release mesalazine, especially in patients with active distal disease. In patients with left-sided ulcerative colitis, oral balsalazide 6.75 g/day appears to be more effective than oral delayed-release mesalazine 2.4 g/day, but a higher dosage of oral delayed-release mesalazine 4.8 g/day may provide additional benefit in these patients. Oral delayed-release mesalazine 0.8 to 4.4 g/day appears to be as effective as sulfasalazine 2 to 4 g/day, prolonged-release mesalazine 1.5 g/day or balsalazide 3 g/day in maintaining remission in patients with ulcerative colitis. The optimal dosage of oral delayed-release mesalazine for the maintenance of remission is unclear. However, oral delayed-release mesalazine 1.6 g/day with rectal mesalazine 4g, administered twice weekly, was more effective than oral drug alone in maintaining remission in patients at high risk of relapse. In patients with left-sided or distal disease oral olsalazine 1 g/day appeared to be superior to oral delayed-release mesalazine 1.2 g/day for maintenance of symptomatic remission. Limited data in patients with Crohn's disease have shown oral delayed-release mesalazine 0.4 to 4.8 g/day to be an effective therapy for active disease (remission in up to 45% of patients) and for quiescent disease (relapse in 34% of recipients over a duration of up to 12 months). Preliminary data indicate that oral delayed-release mesalazine 2.4 g/day is effective in preventing postoperative recurrence of Crohn's disease. Oral delayed-release mesalazine is effective and well tolerated in sulfasalazine-intolerant patients with ulcerative colitis or Crohn's disease.

CONCLUSIONS

Oral delayed-release mesalazine is effective in patients with mild to moderately active or quiescent ulcerative colitis. Available data suggest that patients with left-sided or distal ulcerative colitis are likely to require higher daily dosages of oral delayed-release mesalazine or supplementation with rectal mesalazine. Oral delayed-release mesalazine also appears to be effective in active and quiescent Crohn's disease. The drug is well tolerated and it appears to be effective in sulfasalazine-intolerant patients.