Long-term Outcome of Inflammatory Bowel Disease-Unclassified in Children

Pediatric Inflammatory Bowel Disease Type Unclassified: A Nationwide Cohort Study in Scotland With up to 20 Years Follow-up Shows Reclassification in the Majority and Mild Course in Those Whose Diagnosis Is Unchanged

BACKGROUND

Given the paucity of long-term longitudinal data for inflammatory bowel disease type unclassified (IBDU), we aimed to clarify IBDU disease course and reclassification rate by presenting nationwide data with up to 20 years of follow-up.

METHODS

We analyzed a prospectively identified 11-year cohort of pediatric patients diagnosed with IBDU between January 1, 2003 and December 31, 2013 at all Scottish pediatric IBD centers and followed up into adult services until December 31, 2022. Data were obtained from electronic medical records at fixed timepoints (5 and 10 years post-diagnosis) and at the final follow-up.

RESULTS

Overall, 102 patients were included in the analysis (57/102 [56%] male, median [interquartile range {IQR}] age at diagnosis: 11.5 [9.1-13.2] years) with a median (IQR) follow-up length of 10.5 (8.6-14.0) years. A change of diagnosis was made in 61 of 102 patients (60%); of these, 30 patients (29%) were reclassified to Crohn's disease (CD) and 31 patients (30%) to ulcerative colitis (UC). Patients who remained with IBDU had higher 1- to 5-year remission rates (IBDU 30/39 [77%] vs reclassified 16/57 [28%], P < .05), with lower rates of moderate-to-severe disease (IBDU 3/39 [8%] vs reclassified 31/57 [54%], P < .05) and less need for biologics across all timepoints (IBDU vs reclassified: first timepoint 1/39 [3%] vs 17/57 [30%], second timepoint 1/33 [3%] vs 26/56 [46%], third timepoint 0/18 [0%] vs 16/33 [49%]; all P < .05). Higher rates of surgical resections were observed in reclassified patients (reclassified 11/61 [18%] vs IBDU 1/41 [2%], P = .02).

CONCLUSIONS

In our nationwide pediatric IBDU cohort, 60% of patients were reclassified to either UC or CD over 10.5 years of median follow-up; those who remained with IBDU had a milder disease course.

SYSTEMATIC REVIEW AND META - ANALYSIS OF THE FREQUENCY AND RE-CLASSIFICATION TRENDS OF PEDIATRIC INFLAMMATORY BOWEL DISEASE - UNCLASSIFIED

BACKGROUND

The term inflammatory bowel disease-unclassified (IBDU) is used when an individual has chronic colitis but cannot be sub-typed into ulcerative colitis (UC) or Crohn's disease (CD) on the basis of the clinical, endoscopic, imaging and histopathological features. On follow-up a proportion of patients with IBDU are re-classified as CD or UC. There has been considerable variability in the frequency and reclassification rates of pediatric IBDU in published literature.

METHODS

PubMed and Scopus and were searched for publications related to Pediatric Inflammatory Bowel Disease (PIBD) published between Jan,2014 and July,2021. Two reviewers independently searched and selected studies reporting the frequency of IBDU and/or their re-classification. The pooled prevalence was expressed as proportion and 95%CI. Meta-analysis was performed using the inverse variance heterogeneity model.

RESULTS

A total of 2750 studies were identified through a systematic search of which 27 studies were included in this systematic review. The overall pooled frequency of IBDU (n=16064) was found to be 7.1% (95%CI 5.8-8.5%). There was no variation in IBDU frequency by geographical location. Seven studies (n=5880) were included in the IBDU re-classification analysis. Overall, 50% (95%CI 41-60%) children with IBDU were re-classified on follow-up. Amongst these 32.7% (95% 21-44%) were re-classified to UC and 17% (95%CI 12-22%) were re-classified to CD.

CONCLUSION

IBDU comprises 7.1% of PIBD at initial diagnosis. Half of these children are re-classified into UC or CD on follow-up with a higher likelihood of re-classification to UC as compared to CD.

Pediatric inflammatory bowel disease: Is it really uncommon in Asian children?

Background/Aim

Inflammatory bowel disease (IBD) is said to be rare in Asian children, and there is scarce information from India. We therefore analyzed our experience of pediatric IBD.

Methods

Prospectively maintained data of 105 consecutive children [median age 12 (IQR:7–14) years, 71 males] with IBD from July 2001 through June 2016 were retrospectively analyzed. Their detailed clinical features, endoscopic appearance, histopathology, and treatment outcomes were recorded. For Crohn's disease (CD), disease phenotype and disease location were assessed as per Paris classification.

Results

Disease spectrum includes ulcerative colitis (UC), 55 (52%); CD, 43 (41%); and IBD‐unclassified, 7 (7%). There was a significant increase in the number of cases in the last 5 years compared to the previous 10 years (63 vs. 42, r² = 0.96). Most UC cases (75%) had extensive/pancolitis, 74% of CD had colonic/ileocolonic disease, and 65% had inflammatory phenotype. Fever, growth failure, pain in abdomen, and need for surgery were significantly more frequent in CD than in UC (P < 0.0001). Over a median follow up of 19 (IQR: 7–48) months, remission was achieved in 48 of 51 (94%) UC patients and in 24 of 34 (70.6%) CD patients; an immunomodulator was required to maintain remission in 67% of UC cases. In CD, there was a significant reduction in the use of empirical antitubercular therapy (76%, P = 0.008) with time, and disease progressed in three.

Conclusions

IBD is not uncommon, and the incidence seems to be increasing among Indian children. UC is more common than CD and is more often an extensive disease. CD is mainly an inflammatory phenotype. The majority of children with IBD required an immunomodulator to maintain remission.

An Overview of Inflammatory Bowel Disease Unclassified in Children

BACKGROUND

The inflammatory bowel diseases cover a diverse range of conditions generally grouped into Crohn's disease (CD) or ulcerative colitis (UC) based on clinical, laboratory, radiological, endoscopic, and histological criteria. However, inflammatory bowel disease unclassified (IBDU) is used when there are clinical and endoscopic signs of chronic colitis without specific features of UC or CD but features of both. Conjecture exists regarding IBDU, especially in children, as to whether it represents a unique childhood phenotype or whether it reflects the difficulties in assigning an IBD subtype at an early age.

SUMMARY

This review examines the current understanding of pediatric IBDU and assesses the evidence supporting IBDU as a distinctive disease entity on the spectrum of inflammatory bowel disease.

KEY MESSAGES

Pediatric-onset IBDU is more common than adult-onset IBDU. Therefore, an understanding of IBDU in this age group assumes more importance. However, there remains a paucity of information and a lack of exclusive longitudinal studies on pediatric IBDU. Subsequently there is significant disparity in the reported prevalence, clinical course, reclassification trends, and treatment responses around pediatric IBDU. Therefore, it remains challenging to chart the natural history of pediatric IBDU and consequently form an accurate understanding of where pediatric IBDU sits on the spectrum of disease.