Breaking through the silence: the experience of living with HIV-positive serostatus, and its implications on disclosure

AIDS has reached pandemic proportions and despite advances in medical treatment both the medical and social consequences of HIV-positive serostatus continue to be of concern throughout the world. In countries with greater access to antiretroviral therapy (ARV), HIV/AIDS it is no longer defined as fatal, but rather a chronic disease, thereby this study seeks to understand the experience of individuals living with HIV-positive serostatus, a multifaceted disease, from the time the infection is diagnosed through the four post-diagnosis years, and in particular its implications on the issue of disclosure. A qualitative analysis was conducted, based on 13 in-depth interviews with participants who are HIV-positive and the data was analyzed by inductive content analysis. The results identify six themes, four central elements that compose the experience of living with HIV: the emotional experience, the stigma attached to HIV, the inner dialogue, and disclosure. A three-phase coping process and personality differences were found, all of which will be discussed. The issue of disclosure was found to be cardinal and problematic in its impact on the patient's wellbeing.

IL-10R polymorphisms are associated with very-early-onset ulcerative colitis

BACKGROUND

Interleukin-10 (IL-10) signaling genes are attractive inflammatory bowel disease (IBD) candidate genes as IL-10 restricts intestinal inflammation, IL-10 polymorphisms have been associated with IBD in genome-wide association studies, and mutations in IL-10 and IL-10 receptor (IL-10R) genes have been reported in immunodeficient children with severe infantile-onset IBD. Our objective was to determine if IL-10R polymorphisms were associated with early-onset IBD (EO-IBD) and very-early-onset IBD (VEO-IBD).

METHODS

Candidate-gene analysis of IL10RA and IL10RB was performed after initial sequencing of an infantile onset-IBD patient identified a novel homozygous mutation. The discovery cohort included 188 EO-IBD subjects and 188 healthy subjects. Polymorphisms associated with IBD in the discovery cohort were genotyped in an independent validation cohort of 422 EO-IBD subjects and 480 healthy subjects.

RESULTS

We identified a homozygous, splice-site point mutation in IL10RA in an infantile-onset IBD patient causing a premature stop codon (P206X) and IL-10 insensitivity. IL10RA and IL10RB sequencing in the discovery cohort identified five IL10RA polymorphisms associated with ulcerative colitis (UC) and two IL10RB polymorphisms associated with Crohn's disease (CD). Of these polymorphisms, two IL10RA single nucleotide polymorphisms, rs2228054 and rs2228055, were associated with VEO-UC in the discovery cohort and replicated in an independent validation cohort (odds ratio [OR] 3.08, combined P = 2 x 10(-4); and OR 2.93, P = 6 x 10(-4), respectively).

CONCLUSIONS

We identified IL10RA polymorphisms that confer risk for developing VEO-UC. Additionally, we identified the first splice site mutation in IL10RA resulting in infantile-onset IBD. This study expands the phenotype of IL10RA polymorphisms to include both severe arthritis and VEO-UC.

Alterations in the gut microbiome of children with severe ulcerative colitis

BACKGROUND

Although the role of microbes in disease pathogenesis is well established, data describing the variability of the vast microbiome in children diagnosed with ulcerative colitis (UC) are lacking. This study characterizes the gut microbiome in hospitalized children with severe UC and determines the relationship between microbiota and response to steroid therapy.

METHODS

Fecal samples were collected from 26 healthy controls and 27 children hospitalized with severe UC as part of a prospective multicenter study. DNA extraction, polymerase chain reaction (PCR) amplification of bacterial 16S rRNA, and microarray hybridization were performed. Results were analyzed in GeneSpring GX 11.0 comparing healthy controls with children with UC, and steroid responsive (n = 17) with nonresponsive patients (n = 10).

RESULTS

Bacterial signal strength and distribution showed differences between UC and healthy controls (adjusted P < 0.05) for Phylum, Class, Order, Family, Genus, and Phylospecies levels with reduction in Clostridia and an increase in Gamma-proteobacteria. The number of microbial phylospecies was reduced in UC (266 ± 69) vs. controls (758 ± 3, P < 0.001), as was the Shannon Diversity Index (6.1 ± 0.23 vs. 6.49 ± 0.04, respectively; P < 0.0001). Steroid nonresponders harbored fewer phylospecies than responders (142 ± 49 vs. 338 ± 62, P = 0.013).

CONCLUSIONS

Richness, evenness, and biodiversity of the gut microbiome were remarkably reduced in children with UC compared with healthy controls. Children who did not respond to steroids harbored a microbiome that was even less rich than steroid responders. This study is the first to characterize the gut microbiome in a large cohort of pediatric patients with severe UC and describes changes in the gut microbiome as a potential prognostic feature.

Management of pediatric ulcerative colitis: joint ECCO and ESPGHAN evidence-based consensus guidelines

BACKGROUND AND AIMS

Pediatric ulcerative colitis (UC) shares many features with adult-onset disease but there are some unique considerations; therefore, therapeutic approaches have to be adapted to these particular needs. We aimed to formulate guidelines for managing UC in children based on a systematic review (SR) of the literature and a robust consensus process. The present article is a product of a joint effort of the European Crohn's and Colitis Organization (ECCO) and the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN).

METHODS

A group of 27 experts in pediatric IBD participated in an iterative consensus process including 2 face-to-face meetings, following an open call to ESPGHAN and ECCO members. A list of 23 predefined questions were addressed by working subgroups based on a SR of the literature.

RESULTS

A total of 40 formal recommendations and 68 practice points were endorsed with a consensus rate of at least 89% regarding initial evaluation, how to monitor disease activity, the role of endoscopic evaluation, medical and surgical therapy, timing and choice of each medication, the role of combined therapy, and when to stop medications. A management flowchart, based on the Pediatric Ulcerative Colitis Activity Index (PUCAI), is presented.

CONCLUSIONS

These guidelines provide clinically useful points to guide the management of UC in children. Taken together, the recommendations offer a standardized protocol that allows effective, timely management and monitoring of the disease course, while acknowledging that each patient is unique.

Assessment and management of febrile neutropenia in emergency departments within a regional health authority-a benchmark analysis

OBJECTIVES

Febrile neutropenia is considered an oncologic emergency, for which prompt initiation of antibiotics is essential.

METHODS

We conducted a retrospective cohort study for the 2006 calendar year involving all adult oncology patients presenting with febrile neutropenia to a regional health authority's emergency departments. The objective was to determine the time from triage to antibiotic administration and its impact on patient outcomes.

RESULTS

We identified 68 patients presenting with febrile neutropenia, most of whom (76%) were seen in tertiary care centers. Of those patients, 65% were triaged to be seen within 15 minutes of arrival in the emergency room; however, the median time to reassessment was 57 minutes. The median time from triage to antibiotic administration was 5 hours (range: 1.23-22.8 hours). No increased risk of death or increased length of hospital stay was associated with delayed antibiotic administration. Older patients and patients without caregiver support were more likely to experience delayed antibiotic administration (odds ratio: 3.8 and 12.7 respectively).

CONCLUSIONS

We were not able to show a deleterious effect of delay in antibiotic administration, but our analysis identified several points at which patient flow through the emergency room could be improved.

Role of surgery in severe ulcerative colitis in the era of medical rescue therapy

Despite the growing use of medical salvage therapy, colectomy has remained a cornerstone in managing acute severe ulcerative colitis (ASC) both in children and in adults. Colectomy should be regarded as a life saving procedure in ASC, and must be seriously considered in any steroid-refractory patient. However, colectomy is not a cure for the disease but rather the substitution of a large problem with smaller problems, including fecal incontinence, pouchitis, irritable pouch syndrome, cuffitis, anastomotic ulcer and stenosis, missed or de-novo Crohn’s disease and, in young females, reduced fecundity. This notion has led to the widespread practice of offering medical salvage therapy before colectomy in most patients without surgical abdomen or toxic megacolon. Medical salvage therapies which have proved effective in the clinical trial setting include cyclosporine, tacrolimus and infliximab, which seem equally effective in the short term. Validated predictive rules can identify a subset of patients who will eventually fail corticosteroid therapy after only 3-5 d of steroid therapy with an accuracy of 85%-95%. This accuracy is sufficiently high for initiating medical therapy, but usually not colectomy, early in the admission without delaying colectomy if required. This approach has reduced the colectomy rate in ASC from 30%-70% in the past to 10%-20% nowadays, and the mortality rate from over 70% in the 1930s to about 1%. In general, restorative proctocolectomy (ileoanal pouch or ileal pouch-anal anastomosis), especially the J-pouch, is preferred over straight pull-through (ileo-anal) or ileo-rectal anastomosis, which may still be considered in young females concerned about infertility. Colectomy in the acute severe colitis setting, is usually performed in three steps due to the severity of the inflammation, concurrent steroid treatment and the generally reduced clinical condition. The first surgical step involves colectomy and constructing an ileal stoma, the second - constructing the pouch and the third - closing the stoma. This review focuses on the role of surgical treatment in ulcerative colitis in the era of medical rescue therapy.

Limitations of fecal calprotectin at diagnosis in untreated pediatric Crohn's disease

BACKGROUND

Fecal Calprotectin (FC) is a validated screening test for intestinal inflammation in Crohn's disease (CD). The objective of the study was to prospectively evaluate the limitations of FC for identifying CD in newly diagnosed untreated pediatric patients and to assess the association of FC levels with disease location and serum inflammatory markers.

METHODS

Consecutive children with new onset untreated CD participating in the ongoing ESPGHAN GROWTH CD study were evaluated at diagnosis for disease activity, extent, C-reactive protein (CRP), and FC.

RESULTS

In all, 60 children met the inclusion criteria (mean age 12.6 ± 4.6 years,), 25 (42%) with mild disease, 17 (28%) moderate disease, and 18 (30%) severe disease. Twenty-seven (45%) had small bowel disease only. Median FC levels did not differ between children with small bowel only (2198 μg/g interquartile range [IQR] 696-2400) and those with colonic involvement (with or without small bowel disease; 2400 μg/g (IQR 475-2400) (P = 0.76). FC was elevated in 95% of patients, in comparison to CRP (86%) and erythrocyte sedimentation rate (ESR) (83%). Three children (5%) who had normal calprotectin levels also had low or normal CRP and/or ESR. There was no correlation between calprotectin levels and either the pediatric CD activity index (r = -0.11; P = 0.94) or physicians global assessment.

CONCLUSIONS

FC levels in active disease confined to the small bowel were elevated in the vast majority of children and site of disease was not a confounding factor in this setting. Patients with low FC had a trend toward low levels of inflammatory markers as well. We did not find a significant correlation between FC and clinical indices of activity.

Is pediatric IBD treatment different than in adults?

The incidence of pediatric inflammatory bowel disease (IBD) continues to rise in most countries. Approximately 20-25% of IBD patients present before the age of 20, and their management is associated with many unique challenges. These challenges stem both from the inherent differences between children and adults, and from the differences in the nature and course of the disease. Children with IBD are more likely than adults to present with extensive disease ‑ both in Crohn's disease (CD) and ulcerative colitis (UC). Diagnosis requires a high index of suspicion, as children may present with less typical signs such as poor growth and delayed puberty. In the very young patients with inflammatory bowel disease, the pediatric clinician must consider a broader range of immunological and allergic disorders. Optimal management requires recognition of pediatric patterns of presentation, efficacy and adverse-effect profiles, and understanding monitoring aspects unique to pediatrics. These aspects include pediatric disease-related psychological issues, adherence to therapy and transition to adult care. Inadequate attention to growth, puberty or bone health in childhood can result in long-term consequences, such as impaired adult height and increased risk of fractures. Management of pediatric IBD and prevention of adverse long-term consequences relies on a variety of therapies well-known to the adult practitioner, along with therapies that are not widespread in adults, most notably exclusive enteral nutrition (EEN). The latter is as effective as corticosteroids in achieving clinical remission in children, while achieving better results than corticosteroids with regard to mucosal healing and growth. This review discusses the broad variety of issues that form the basis for management of pediatric IBD.

Controlling soot formation with filtered EGR for diesel and biodiesel fuelled engines

Although exhaust gas recirculation (EGR) is an effective strategy for controlling the levels of nitrogen oxides (NO(X)) emitted from a diesel engine, the full potential of EGR in NO(X)/PM trade-off and engine performance (i.e., fuel economy) has not fully been exploited. Significant work into the cause and control of particulate matter (PM) has been made over the past decade with new cleaner fuels and after-treatment devices emerging to comply with the current and forthcoming emission regulations. In earlier work, we demonstrated that engine operation with oxygenated fuels (e.g., biodiesel) reduces the PM emissions and extends the engine tolerance to EGR before it reaches smoke-limited conditions. The same result has also been reported when high cetane number fuels such as gas-to-liquid (GTL) are used. To further our understanding of the relationship between EGR and PM formation, a diesel particulate filter (DPF) was integrated into the EGR loop to filter the recirculated soot particulates. The control of the soot recirculation penalty through filtered EGR (FEGR) resulted in a 50% engine-out soot reduction, thus showing the possibility of extending the maximum EGR limit or being able to run at the same level of EGR with an improved NO(X)/soot trade-off.

Syphilis outbreak among men who have sex with men, Tel Aviv, Israel, 2008-2009

BACKGROUND

Outbreaks of syphilis have been described among men who have sex with men (MSM) in many western urban communities in the last few years.

OBJECTIVES

To describe the first reported outbreak of syphilis among MSM in Israel within a decade of a constant increase in human immunodeficiency virus (HIV) prevalence.

METHODS

All patients diagnosed with syphilis were contacted and asked about their sexual behavior, substance use and previous infections. All were tested for HIV and a phylogenetic analysis was performed.

RESULTS

A total of 23 (59%) of all 39 male patients diagnosed with primary or secondary syphilis between August 2008 and August 2009 were interviewed. All were MSM and performed anal intercourse, while 13 (55%) reported unprotected anal intercourse. Most participants (21, 91%) practiced unprotected oral intercourse. Nine participants (39%) reported unprotected oral intercourse while using condoms during anal intercourse. Ten participants (43%) reported sexual contacts while traveling abroad in the previous few months. Most participants (96%) were co-infected with HIV, and 15 (68%) were already aware of their HIV infection. Fifteen (66%) reported the use of recreational drugs, alcohol, or both before or during sex. No common source or core transmitters were identified.

CONCLUSIONS

This syphilis outbreak included MSM who were co-infected with HIV and were characterized by risky sexual behavior including multiple partners, unprotected anal intercourse and substance use. Future targeted interventions should focus on HIV-infected MSM for secondary prevention.

Mathematical weighting of the pediatric Crohn's disease activity index (PCDAI) and comparison with its other short versions

BACKGROUND

The Pediatric Crohn's Disease Activity Index (PCDAI) has become the standard outcome measure in pediatric Crohn's disease (CD) clinical research. Other versions have been proposed but without systematic evaluation. The aim was to assess validity and responsiveness of the abbreviated PCDAI (abbrPCDAI), short PCDAI (shPCDAI), and modified PCDAI (modPCDAI) as measures of disease activity and to compare these with a mathematically weighted version developed here (wPCDAI).

METHODS

The raw data from four prospectively collected datasets were used, totaling 437 children with CD (including two clinical trials). Discriminant validity utilized physician global assessment of disease activity (PGA), and construct validity the correlation with PGA and laboratory results. Feasibility and face validity were ascertained by a survey of 33 experts in pediatric CD.

RESULTS

The wPCDAI had better performance than the PCDAI in construct validity and responsiveness and it discriminated better between the disease activity categories (area under the receiver operator characteristic [ROC] 0.97; 95% confidence interval [CI]: 0.95-0.99). In comparison to the original PCDAI, the noninvasive versions (abbrPCDAI and shPCDAI) had lower face, construct, and discriminant validity but were judged to be significantly more feasible. The modPCDAI performed well in the construct validation but was consistently inferior in all other parameters. Cutoffs that correspond to remission, response, and gradations of disease activity were determined for each index.

CONCLUSIONS

The newly weighted wPCDAI performed better than the original PCDAI and is more feasible. The noninvasive versions (shPCDAI and abbrPCDAI) are inferior to the full PCDAI, but when needed in retrospective studies either may be equally used.

A clinical prediction rule and platelet count predict esophageal varices in children

BACKGROUND & AIMS

The validation of noninvasive tests to diagnose esophageal varices is a priority in children because repeated endoscopic evaluations are too invasive. We measured the ability of a previously developed noninvasive clinical prediction rule (CPR) to predict the presence of esophageal varices in children.

METHODS

We analyzed data from 108 children, younger than age 18, who received endoscopies at 8 centers, to assess portal hypertension from chronic liver disease or portal vein obstruction. Blood test and abdominal ultrasound scan results were obtained within 4 months of endoscopy. Grading of varices identified by endoscopy was confirmed by independent blinded review. Spleen size, based on data from the ultrasound scan, was expressed as a standard deviation score relative to normal values for age.

RESULTS

Of the children studied, 74 had esophageal varices (69%), including 35 with large varices (32%). The best noninvasive predictors of esophageal varices of any size were as follows: platelet:spleen size z-score ratio (area under the receiver operating characteristic curve [AUROC], 0.84; 95% confidence interval [CI] 0.75-0.93), CPR (AUROC, 0.80; 95% CI, 0.70-0.91), and platelet count (AUROC, 0.79; 95% CI, 0.69-0.90). The positive predictive values for the CPR and platelet count were 0.87 and 0.86, the negative predictive values were 0.64 and 0.63, the positive likelihood ratios were 3.06 and 2.76, and the negative likelihood ratios were 0.64 and 0.63, respectively. Based on positive and negative predictive values, the most accurate noninvasive tests were the CPR and platelet counts.

CONCLUSIONS

Noninvasive tests such as CPR and platelet count can assist in triaging children for endoscopy to identify esophageal varices.

Emergence of an HIV-1 cluster harbouring the major protease L90M mutation among treatment-naïve patients in Tel Aviv, Israel

OBJECTIVE

Drug resistance-associated mutations (DRMs) among HIV-1 treatment-naïve patients have increased in recent years. Their incidence and prevalence in various exposure risk categories (ERCs) were evaluated.

DESIGN

Plasma samples of HIV-1 treatment-naïve patients diagnosed between 2001 and 2009 at the Tel Aviv Medical Center were screened for DRMs.

METHODS

Samples obtained from patients following the HIV diagnosis were analysed retrospectively. Genotyping was carried out using the Trugene HIV-1 genotype kit (Siemens, Berkeley, CA, USA). Phylogenetic relationships among viral sequences were estimated using the maximum likelihood method.

RESULTS

Thirty-eight of the 266 analysed sequences (14.3%) had DRMs, all occurring exclusively in the group of men who have sex with men (MSM). The rate of DRMs has constantly risen, reaching a peak of 21.9% in 2009. Notably, protease inhibitor (PI) DRMs became the most frequent DRMs in 2009. Phylogenetic analysis showed a tight cluster comprising 13 of 14 viruses harbouring the L90M major PI resistance mutation, suggesting a single infection source.

CONCLUSION

There was an unexpectedly high rate of the major L90M PI resistance mutation in the MSM group. The clustered transmission of this mutation might be related to a high-risk sexual behaviour. Added to nonnucleoside reverse transcriptase inhibitor and nucleoside reverse transcriptase inhibitor resistance mutations, such a PI mutation may limit future therapeutic options for this particular patient population.

C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) or both? A systematic evaluation in pediatric ulcerative colitis

BACKGROUND

There has not been an extensive comparison of CRP and ESR in ulcerative colitis (UC), and thus, we aimed to explore their utility in UC.

METHODS

Four previously enrolled cohorts of 451 children with UC were utilized, all including laboratory, clinical and endoscopic data. A longitudinal analysis was performed on prospectively collected data of 75 children. Disease activity was captured by both global assessment and pediatric UC activity index (PUCAI).

RESULTS

The best thresholds to differentiate quiescent, mild, moderate and severe disease activity, were <23, 23-29, 30-37, >37 mm/h for ESR, and <2.5, 2.5-5, 5.01-9, >9 mg/L for CRP (area under the ROC curves 0.70-0.81). Correlation of endoscopic appearance with CRP and ESR were 0.55 and 0.41, respectively (P<0.001). Both CRP and ESR may be completely normal in 34% and 5-10% of those with mild and moderate-severe disease activity, respectively. Elevated CRP in the presence of normal ESR or vice versa was noted in 32%, 38%, 30% and 17% of those with quiescent, mild, moderate and severe disease activity. Over time, the utility of CRP and ESR in reflecting disease activity remained stable in 70-80% of cases.

CONCLUSION

In ~2/3 of children, both CRP and ESR values reflect disease activity to a similar degree and in the remaining, either CRP or ESR may be sufficient, with slight superiority of CRP. CRP is more closely correlated with endoscopic appearance. When either CRP or ESR performs well for a given patient, this is likely to remain so over time. Therefore, it may not be justified to routinely test both ESR and CRP in monitoring disease activity.

Update of fecal markers of inflammation in inflammatory bowel disease

The diagnosis, prognosis, and assessment of disease activity of inflammatory bowel disease (IBD) require investigating clinical, radiological, and histological criteria, as well as serum inflammatory markers. However, a range of fecal inflammatory markers now appears to have the potential to greatly assist in these processes. Calprotectin, a prominent neutrophil protein, was identified two decades ago as a potentially revolutionary marker for IBD. Following this discovery, numerous additional markers, including S100A12, lactoferrin, and M2-pyruvate kinase, have also been suggested as novel markers of IBD. In the present study, we provide an up-to-date review of fecal markers of IBD, and further, provide a novel analysis of each of these fecal markers in severe ulcerative colitis and compare their expression pattern in contrast to calprotectin.

Fecal osteoprotegerin may guide the introduction of second-line therapy in hospitalized children with ulcerative colitis

BACKGROUND

Osteoprotegerin (OPG) is increased in inflamed colonic mucosa and has a role in immune regulation and apoptosis resistance. Fecal OPG may be useful in predicting corticosteroid resistance in hospitalized children with severe ulcerative colitis (UC). We aimed to determine whether fecal OPG predicts the need for second-line therapies in children hospitalized for UC.

METHODS

We included 83 children with UC admitted for intravenous corticosteroid treatment. Children were classified as responders/nonresponders based on the need for therapy escalation. Fecal OPG results were compared with those of four other fecal markers.

RESULTS

Of the enrolled children, seven had day 1 samples only, 53 children had day 3 samples only, and 23 had both. Twenty-two children failed corticosteroid therapy and required infliximab (n = 20) or colectomy (n = 2). On the third treatment day the median fecal OPG levels were significantly higher in the nonresponders group compared with the responders: 77 pmol/L (interquartile range [IQR] 27-137) versus 13 pmol/L (3-109); P = 0.007. The best day 3 fecal OPG cutoff to predict second-line therapy was >50 pmol/L with a sensitivity of 71% and specificity of 69% (area under the receiver operator curve [ROC] of 0.70%-95% confidence interval [CI] 0.57-0.82). Fecal OPG was superior to day 3 fecal calprotectin, lactoferrin, and S100A12 as a predictor of corticosteroid nonresponse, but equivalent to the less commonly used M2-pyruvate kinase.

CONCLUSIONS

Day 3 fecal OPG may guide the decision to institute second-line therapy in children with severe UC. The role of OPG in the inflammatory response in pediatric UC deserves further study.

Single nucleotide polymorphisms that increase expression of the guanosine triphosphatase RAC1 are associated with ulcerative colitis

BACKGROUND & AIMS

RAC1 is a guanosine triphosphatase that has an evolutionarily conserved role in coordinating immune defenses, from plants to mammals. Chronic inflammatory bowel diseases are associated with dysregulation of immune defenses. We studied the role of RAC1 in inflammatory bowel diseases using human genetic and functional studies and animal models of colitis.

METHODS

We used a candidate gene approach to HapMap-Tag single nucleotide polymorphisms in a discovery cohort; findings were confirmed in 2 additional cohorts. RAC1 messenger RNA expression was examined from peripheral blood cells of patients. Colitis was induced in mice with conditional disruption of Rac1 in phagocytes by administration of dextran sulfate sodium.

RESULTS

We observed a genetic association between RAC1 with ulcerative colitis in a discovery cohort, 2 independent replication cohorts, and in combined analysis for the single nucleotide polymorphisms rs10951982 (P(combined UC) = 3.3 × 10(-8), odds ratio = 1.43 [95% confidence interval: 1.26-1.63]) and rs4720672 (P(combined UC) = 4.7 × 10(-6), odds ratio = 1.36 [95% confidence interval: 1.19-1.58]). Patients with inflammatory bowel disease who had the rs10951982 risk allele had increased expression of RAC1 compared to those without this allele. Conditional disruption of Rac1 in macrophage and neutrophils of mice protected against dextran sulfate sodium-induced colitis.

CONCLUSIONS

Human studies and knockout mice demonstrated a role for the guanosine triphosphatase RAC1 in the development of ulcerative colitis; increased expression of RAC1 was associated with susceptibility to colitis.

Pediatric modification of the Montreal classification for inflammatory bowel disease: the Paris classification

BACKGROUND

Crohn's disease and ulcerative colitis are complex disorders with some shared and many unique predisposing genes. Accurate phenotype classification is essential in determining the utility of genotype-phenotype correlation. The Montreal Classification of IBD has several weaknesses with respect to classification of children. The dynamic features of pediatric disease phenotype (change in disease location and behavior over time, growth failure) are not sufficiently captured by the current Montreal Classification.

METHODS

Focusing on facilitating research in pediatric inflammatory bowel disease (IBD), and creating uniform standards for defining IBD phenotypes, an international group of pediatric IBD experts met in Paris, France to develop evidence-based consensus recommendations for a pediatric modification of the Montreal criteria.

RESULTS

Important modifications developed include classifying age at diagnosis as A1a (0 to <10 years), A1b (10 to <17 years), A2 (17 to 40 years), and A3 (>40 years), distinguishing disease above the distal ileum as L4a (proximal to ligament of Treitz) and L4b (ligament of Treitz to above distal ileum), allowing both stenosing and penetrating disease to be classified in the same patient (B2B3), denoting the presence of growth failure in the patient at any time as G(1) versus G(0) (never growth failure), adding E4 to denote extent of ulcerative colitis that is proximal to the hepatic flexure, and denoting ever severe ulcerative colitis during disease course by S1.

CONCLUSIONS

These modifications are termed the Paris Classification. By adhering to the Montreal framework, we have not jeopardized or altered the ability to use this classification for adult onset disease or by adult gastroenterologists.