Glucocorticoid receptor mRNA in patients with ulcerative colitis: a study of responders and nonresponders to glucocorticosteroid therapy

Systemic glucocorticoid therapy and adrenal insufficiency in adults: A systematic review

OBJECTIVES

The aim of this systematic literature review was to summarize the current knowledge regarding the prevalence of, time to recovery from, and influence of glucocorticoid dose and duration on glucocorticoid-induced adrenal insufficiency (AI).

METHODS

Eligible studies were original research articles, which included adult patients with an indication for glucocorticoids and measured adrenal function following exposure to systemic glucocorticoids. Searches were performed in Web of Science and MEDLINE, with further articles identified from reference lists. Screening was performed in duplicate. Data were extracted for each group of glucocorticoid-exposed patients within eligible studies. The reported proportion of patients with AI was summarized as median and inter-quartile range. Results were then stratified by daily dose, cumulative dose, duration of exposure and time since last glucocorticoid use. The risk of bias within and across studies was considered: for randomised controlled trials risk of bias was assessed using the tool developed by the Cochrane Collaboration.

RESULTS

Overall, 73 eligible studies were identified out of 673 screened. The percentage of patients with AI ranged from 0% to 100% with a median (IQR) = 37.4% (13-63%). Studies were small-median (IQR) group size 16 (9-38)-and heterogeneous in methodology. AI persisted in 15% of patients retested 3 years after glucocorticoid withdrawal. Results remained widely distributed following stratification. AI was demonstrated at <5mg prednisolone equivalent dose/day, <4 weeks of exposure, cumulative dose <0.5g, and following tapered withdrawal.

CONCLUSIONS

The heterogeneity of studies and variability in results make it difficult to answer the research questions with confidence based on the current literature. There is evidence of AI following low doses and short durations of glucocorticoids. Hence, clinicians should be vigilant for adrenal insufficiency at all degrees of glucocorticoid exposure.

Review article: The pharmacokinetics and pharmacodynamics of drugs used in inflammatory bowel disease treatment

BACKGROUND

The following review is a compilation of the recent advances and knowledge on the behaviour of the most frequently used compounds to treat inflammatory bowel disease in an organism.

RESULTS

It considers clinical aspects of each entity and the pharmacokinetic/pharmacodynamic relationship supported by the use of plasma monitoring, tissue concentrations, and certain aspects derived from pharmacogenetics.

Glucocorticoid sensitivity in inflammatory bowel disease

Glucocorticoid therapy is used in the treatment of moderate to severe inflammatory bowel disease (IBD). However, IBD patients display varying degrees of glucocorticoid sensitivity: some respond rapidly to the given treatment, whereas others show no response, or develop steroid therapy-related side-effects. At present, we cannot foresee whether the patient will benefit from the administered glucocorticoids or not. During the past 10 years, numerous attempts have been made to provide the means to identify and predict steroid therapy-sensitive patients in advance. This would be vital to avoid unnecessary glucocorticoid exposure in patients that do not respond to treatment with steroids. Here we provide a concise review of recent developments regarding the molecular basis of glucocorticoid sensitivity in IBD patients and the methods employed to assess it.

Glucocorticoids in pediatric inflammatory bowel disease

Children with moderate to severe inflammatory bowel disease (IBD) are treated with systemic glucocorticoids (GCs). The majority of the patients respond to the given treatment; however, steroid resistance and dependency are significant clinical problems. Also therapy-related side effects limit the use of GCs in the control of active inflammation. This review summarizes recent knowledge of GC treatment in pediatric patients with IBD.

Gene expression changes associated with resistance to intravenous corticosteroid therapy in children with severe ulcerative colitis

BACKGROUND AND AIMS

Microarray analysis of RNA expression allows gross examination of pathways operative in inflammation. We aimed to determine whether genes expressed in whole blood early following initiation of intravenous corticosteroid treatment can be associated with response.

METHODS

From a prospectively accrued cohort of 128 pediatric patients hospitalized for intravenous corticosteroid treatment of severe UC, we selected for analysis 20 corticosteroid responsive (hospital discharge or PUCAI ≤45 by day 5) and 20 corticosteroid resistant patients (need for second line medical therapy or colectomy, or PUCAI >45 by day 5). Total RNA was extracted from blood samples collected on day 3 of intravenous corticosteroid therapy. The eluted transcriptomes were quantified on Affymetrix Human Gene 1.0 ST arrays. The data was analysed by the local-pooled error method for discovery of differential gene expression and false discovery rate correction was applied to adjust for multiple comparisons.

RESULTS

A total of 41 genes differentially expressed between responders and non-responders were detected with statistical significance. Two of these genes, CEACAM1 and MMP8, possibly inhibited by methylprednisolone through IL8, were both found to be over-expressed in non-responsive patients. ABCC4 (MRP4) as a member of the multi-drug resistance superfamily was a novel candidate gene for corticosteroid resistance. The expression pattern of a cluster of 10 genes selected from the 41 significant hits were able to classify the patients with 80% sensitivity and 80% specificity.

CONCLUSIONS

Elevated expression of several genes involved in inflammatory pathways was associated with resistance to intravenous corticosteroid therapy early in the course of treatment. Gene expression profiles may be useful to classify resistance to intravenous corticosteroids in children with severe UC and assist with clinical management decisions.

Pharmacogenomics in the treatment of inflammatory bowel disease

In recent years, the benefits of early aggressive treatment paradigms for inflammatory bowel disease have emerged. Symptomatic improvement is no longer considered adequate; instead, the aim of treatment has become mucosal healing and altered natural history. Nonetheless, we still fail to achieve these end points in a large number of our patients. There are many reasons why patients fail to respond or develop toxicity when exposed to drugs used for inflammatory bowel disease, but genetic variation is likely to account for a significant proportion of this. Some examples, notably thiopurine methyltransferase polymorphism in thiopurine treatment, are already established in clinical practice. We present a review of the expanding literature in this field, highlighting many interesting developments in pharmacogenomics applied to inflammatory bowel disease and, where possible, providing guidance on the translation of these developments into clinical practice.

Glucocorticoid bioactivity does not predict response to steroid therapy in severe pediatric ulcerative colitis

BACKGROUND

The pathophysiological basis for corticosteroid (CS) failure in ulcerative colitis (UC) is unknown. A transactivation glucocorticoid bioassay (GBA) was developed to measure the biological activity of CS by quantifying glucocorticoid response elements. This approach eliminates differences in bioavailability, chemistry, affinity, and other potential differences between the various steroids regarding their ability to activate the glucocorticoid receptor. In this multicenter prospective study, we aimed to evaluate whether CS bioavailability plays a role in CS refractoriness in severe pediatric UC.

METHODS

GBA (using COS-1 transfected cells) was measured in the serum of 50 children (52% males, age 13.4 +/- 3.5 years) admitted for acute severe UC on the third day of CS treatment. Demographic, clinical, and laboratory data were prospectively recorded.

RESULTS

Of the children enrolled, 16 (32%) failed CS therapy and required infliximab (n = 14) or colectomy (n = 2) within a median of 10 days (interquartile range [IQR] 6.5-14.5). Reflecting internal validity of the assay, GBA was highly correlated with the last CS dose and the time interval to bloodletting (r = -0.41 and r = -0.54, respectively; P < 0.001). There was no statistically significant difference in the GBA levels between responders and nonresponders (249 nM versus 200 nM cortisol equivalent, P = 0.18). In a multivariate regression model adjusted for time elapsed from CS and the administered dose, GBA did not predict response to CS (P = 0.34).

CONCLUSIONS

The lack of correlation of GBA level and treatment outcome lends support to the hypothesis that the bioavailability, type, and dosing of intravenous CS are not associated with response or failure to the drug.

Treatment of steroid-naive ulcerative colitis

The introduction of steroid therapy by Truelove and Witts in the 1950s revolutionized the treatment of ulcerative colitis. Corticosteroids are potent inhibitors of T-cell activation and proinflammatory cytokines and still represent the mainstay of therapy of patients with ulcerative colitis. About 15% of patients are resistant to steroids, and about a quarter of patients become dependent within 1 year of therapy. Steroid-related adverse events are numerous and occur frequently. So, new steroids with low systemic absorption and better safety profile have been studied, but they show an overall lower efficacy compared with traditional steroids. A new drug-delivery system based on the use of autologous erythrocytes loaded with dexamethasone 21-phosphate has been recently developed. Several studies have demonstrated its efficacy in steroid-dependent patients leading to complete withdrawal of oral steroids and disappearance of the most steroid-related adverse events. In this review we elaborate on the role of steroids in the treatment of ulcerative colitis, focusing on the aspects related to the mechanisms of action and resistance to the steroids, and their secondary effects. Moreover, we analyse the alternatives to traditional systemic steroids such as the new steroids with low bioavailability and the steroids encapsulated into erythrocytes.

Refractory ulcerative colitis and iatrogenic colorectal Kaposi's sarcoma

Colorectal Kaposi's sarcoma, a human herpes virus-8 associated mesenchymal tumour, is exceedingly rare in human immunodeficiency virus-negative subjects and almost always reported in association with severe, refractory, inflammatory bowel disease. In this paper we report a case--the second from Italy--of a colorectal Kaposi's sarcoma in a human immunodeficiency virus-negative, heterosexual man with severe refractory ulcerative colitis. Kaposi's sarcoma developed after starting glucocorticosteroid therapy, supporting the theory that colorectal Kaposi's sarcoma associated with ulcerative colitis is iatrogenic.

Steroid-refractory severe ulcerative colitis: what are the available treatment options?

Approximately 15% of patients with ulcerative colitis will experience a severe episode requiring hospitalization. Although intravenous corticosteroids are the current first-line therapy for these patients, about 30% of patients do not respond to corticosteroids and require either an alternative anti-inflammatory agent or surgery. Ciclosporin has proven its efficacy in a number of controlled trials in this setting and is characterized by high early response rates. Patients who respond to ciclosporin and avoid colectomy are more likely to retain their colon if they bridge to immunomodulators in the medium term. Infliximab has also demonstrated efficacy in reducing early colectomy rates and longer term data are awaited. Other agents, such as tacrolimus and basiliximab, and leukocytapheresis, have been studied in small trials and may be alternative options. Key issues remain as to what should be first- and second-line therapies, when surgery should be undertaken, and the risk of switching between immunosuppressants in these critical patients.

Review article: steroid resistance in inflammatory bowel disease - mechanisms and therapeutic strategies

BACKGROUND

Steroid resistance in inflammatory bowel disease presents a difficult clinical challenge. The advent of biological therapies coupled with an increasing understanding of the pathogenesis of inflammatory bowel disease has provided new therapeutic options.

METHODS

We review the available literature of the mechanisms behind steroid resistance. In addition, we outline some of the options available for treating those patients who fail to respond adequately to glucocorticoids.

RESULTS

Approximately 30% of patients prescribed glucocorticoids will not achieve clinical remission. Many such patients are offered immunosuppressive or, recently, biological agents. However, these agents are ineffective in a large proportion of patients. Immunosuppressive agents only bring 40-60% of patients into remission, and biological agents typically induce remission in just 40% of patients. In this review, the possible explanations for glucocorticoid resistance are discussed. Recent evidence suggests that in many patients it is mediated by interleukin-2. Basiliximab, a biological agent that interrupts interleukin-2 signalling, has shown significant benefit in early clinical studies.

CONCLUSIONS

Patients who fail to respond to steroid therapy should have alternative agents introduced in a timely fashion. Steroid refractory inflammatory bowel disease remains a difficult condition to treat, but new therapies and managements are emerging.

Update in medical therapy of ulcerative colitis: newer concepts and therapies

Recent advances in the pathogenesis of ulcerative colitis recognize the interface of genetic susceptibility, environmental factors (eg, gut microflora), and an altered host's immune response. The meteoric evolution of new therapies designed to address these pathogenetic factors may lead to confusing and often confounding treatment programs. This review is designed to assist the practitioner when in [corrected] incorporating new or novel therapies into a treatment program. These decisions are based on new clinical trial data and the experience of seasoned gastroenterologists with established remedies. NEWER CONCEPTS AND THERAPIES IN UC 5-ADA-- 1. Remains drug of choice for induction and maintenance of remission in mild to moderate IC.1,2 2. Rare but increased incidence of renal disease exists but benefits outweigh risks.18-20 3. Chemoprevention of colorectal cancer in UC is promising and may be related to higher dose and a lessened degree of inflammation.29-36 4. Bioequivalence of all USA 5-ASA is established. Choice of a 5-ASA preparation is not dependent on superiority of a particular mesalamine.3 Phosphodiesterase Inhibitor (OPC-6525)37: preliminary data promising Immunomodulators 6MP/AZA 1. long-term effect not waning51 2. concerns over lymphoma voiced but overall benefits outweigh risks64-70 3. 6MP metabolites measurements of increasing use52-56 Cyclosporine experience continues but serious adverse events remains.105-114 Biologics Infliximab--somewhat disappointing in CUC, awaiting RCT87-92 Basiliximab--useful as "steroid sensitizer" in previously steroid resistant patients118-120 Visilizumab--promising as alternative to cyclosporin in server U.C.115-117 Apheresis--and emerging "non-drug" treatment alternative121-135 Probiotics--Useful in pouchitis and some mild to moderate U.C.94-98, 154 ISIS topical therapy useful in early pilot study (pouchitis)151 Budesonide (pouchitis)147 Antibiotics (pouchitis)140-146 [corrected]

Can we alter the natural history of Crohn disease in children?

The natural history of Crohn disease is characterized by recurrent bouts of active disease, the consequences of which can severely impair sufferers' physical and social functioning. Not only does the illness cause day-to-day morbidity for children but the consequence of the chronic inflammatory process also commonly results in the need for major intestinal surgery. The present challenge facing physicians treating children with Crohn disease is to alleviate symptoms and prolong periods of remission via the use of specifically targeted therapies while minimizing toxicity and promoting normal growth and development. Although systemic corticosteroids are effective in inducing clinical remission, they are of little or no benefit in maintaining remission and can contribute to linear growth retardation. Immunomodulating drugs such as azathioprine, 6-mercaptopurine and methotrexate have proved effective for inducing and maintaining remission of active Crohn disease. These agents are now commonly prescribed in children at diagnosis, after a severe attack or after surgery or in those who become corticosteroid-dependent or corticosteroid-resistant. Their use is not without potential adverse effects and not all patients respond well to these agents. With the introduction of biologic agents, notably the tumor necrosis factor-alpha monoclonal antibody infliximab, progress has been made in targeting specific pathogenetic mechanisms of Crohn disease and potentially altering the underlying disease process. Published experience in children is currently limited, but infliximab has been shown to improve symptoms and achieve corticosteroid independence in this age group. Unresolved issues with infliximab and other emerging biologic agents, including long-term safety, necessitate a degree of caution in selecting appropriate patients for treatment and with careful monitoring of their effects. The collection of contemporary natural history data is crucial to facilitate the better integration of current and emerging therapies in an attempt to alter the natural history of Crohn disease in children.

Medical therapy for ulcerative colitis 2004

There continue to be evolutionary changes in the management of ulcerative colitis despite the fact that, aside from a variety of aminosalicylate formulations, no new therapies have been approved over the past few decades. Nevertheless, debates continue regarding the optimization of treatment with aminosalicylates and the short- and long-term benefits of immunomodulation in ulcerative colitis. This article focuses on the most recent clinical studies pertaining to the management of ulcerative colitis and explores both the advances and controversies pertaining to aminosalicylate therapy, corticosteroids, cyclosporine, and the purine antimetabolites. Novel therapeutic approaches--including preliminary experience with biological therapies directed at tumor necrosis factor and other cytokines, adhesion molecules, growth factors, and probiotics--will be reviewed. Recent data regarding potential chemoprevention in long-standing ulcerative colitis and management of postoperative complications and pouchitis will also be discussed.

Glucocorticoid receptor expression in inflammatory bowel disease: evidence for a mucosal down-regulation in steroid-unresponsive ulcerative colitis

BACKGROUND

Glucocorticoids (GC) play a major role in the attenuation of inflammation. Glucocorticoid receptor (GR) expression is an important determinant of steroid sensitivity.

AIMS

To investigate whether GR mRNA expression is altered in inflammatory bowel disease, and whether GR mRNA expression correlates with disease activity and may predict response to GC therapy.

METHODS

Mucosal biopsies were taken from 33 patients with ulcerative colitis, 21 with Crohn's disease and 11 controls. Peripheral blood mononuclear cells were isolated from 24 ulcerative colitis and 18 Crohn's disease patients and 11 controls. GR mRNA was measured by quantitative reverse transcriptase polymerase chain reaction (RT-PCR), and correlated to endoscopic findings, clinical activity and outcome of GC therapy. In a subset of subjects GR localisation was shown by immunohistochemistry.

RESULTS

In patients with inflammatory bowel disease GR expression was not different from controls. However, GR was decreased in biopsies from ulcerative colitis patients with impaired GC response. The inhibitory subtype GRbeta was expressed 100-1000 times lower than GRalpha. GR immunoreactivity was identified in immune and epithelial cells except for colonic crypts.

CONCLUSION

In inflammatory bowel disease systemic and mucosal GR mRNA expression is not altered. However, in ulcerative colitis patients, low mucosal GR expression may predict the outcome of GC therapy. The low expression of GRbeta challenges its role in steroid refractoriness in inflammatory bowel disease.