Methods: Consecutive patients with PCD were identified from the HKIBDR, and disease characteristics, treatments, and outcomes were analysed. The risks for medical and surgical therapies were assessed using Kaplan-Meier analysis.
Results: Among 981 patients with CD with 10530 patient-years of follow-up, 283 [28.8%] had perianal involvement, of which 120 [42.4%] were as first presentation. The mean age at diagnosis of PCD was 29.1 years, and 78.8% were male. The median follow-up duration was 106 months (interquartile range [IQR]: 65-161 months]. Perianal fistula [84.8%] and perianal abscess [52.7%] were the two commonest forms. Male, younger age at diagnosis of CD, and penetrating phenotypes were associated with development of PCD in multivariate analysis. Of 242 patients with fistulizing PCD, 70 [29.2%] required ≥5 courses of antibiotics, and 98 [40.5%] had ≥2 surgical procedures. Nine patients required defunctioning surgery and 4 required proctectomy. Eighty-four patients [34.7%] received biologics. Cumulative probabilities for use of biologics were 4.7%, 5.8%, and 8.6% at 12 months, 36 months, and 96 months, respectively, while the probabilities for surgery were 67.2%, 71.6%, and 77.7%, respectively. Five mortalities were recorded, including 2 cases of anal cancer, 2 CD-related complications, and one case of pneumonia.
Conclusion: Over 40% of CD patients presented with perianal disease at diagnosis. Patients with PCD had poor outcome, with young age of onset, multiple antibiotic use, and repeated surgery.
AIM: To evaluate the rate of relapse in perianal Crohn's disease (CD) after stopping anti-TNF therapy.
METHODS: Consecutive perianal CD patients treated with anti-TNF therapy with subsequent discontinuation were retrieved from prospective inflammatory bowel disease database of institutes in Hong Kong, Shanghai, Taiwan, Malaysia, Thailand and Singapore from 1997 to June 2019. Cumulative probability of perianal CD relapse was estimated using Kaplan-Meier method.
RESULTS: After a median follow-up of 89 months (interquartile range [IQR]: 65-173 months), 44 of the 78 perianal CD patients (56.4%) relapsed after stopping anti-TNF, defined as increased fistula drainage or recurrence of previously healed fistula, after stopping anti-TNF therapy. Cumulative probabilities of perianal CD relapse were 50.8%, 72.6% and 78.0% at 12, 36 and 60 months, respectively. Younger age at diagnosis of CD [adjusted hazard ratio (HR): 1.04; 95% CI 1.01-1.09; P = .04] was associated with a higher chance of perianal CD relapse. Among those with perianal CD relapse (n = 44), retreatment with anti-TNF induced remission in 24 of 29 patients (82.8%). Twelve (27.3%) patients required defunctioning surgery and one (2.3%) required proctectomy. Maintenance with thiopurine was not associated with a reduced likelihood of relapse [HR = 1.10; 95% CI: 0.58-2.12; P = .77]. Among the 17 patients who achieved radiological remission of perianal CD, five (35.3%) developed relapse after stopping anti-TNF therapy after a median of 6 months.
CONCLUSIONS: More than half of the perianal CD patients developed relapse after stopping anti-TNF therapy. Most regained response after resuming anti-TNF. However, more than one-fourth of the perianal CD patients with relapse required defunctioning surgery. Radiological assessment before stopping anti-TNF is crucial in perianal CD.
METHODS: We performed a prospective, population-based study of IBD incidence in predefined catchment areas, collecting data for 1 year, starting on April 1, 2011. New cases were ascertained from multiple overlapping sources and entered into a Web-based database. Cases were confirmed using standard criteria. Local endoscopy, pathology, and pharmacy records were searched to ensure completeness of case capture.
RESULTS: We identified 419 new cases of IBD (232 of ulcerative colitis [UC], 166 of Crohn's disease [CD], and 21 IBD-undetermined). The crude annual overall incidence values per 100,000 individuals were 1.37 for IBD in Asia (95% confidence interval: 1.25-1.51; 0.76 for UC, 0.54 for CD, and 0.07 for IBD-undetermined) and 23.67 in Australia (95% confidence interval: 18.46-29.85; 7.33 for UC, 14.00 for CD, and 2.33 for IBD-undetermined). China had the highest incidence of IBD in Asia (3.44 per 100,000 individuals). The ratios of UC to CD were 2.0 in Asia and 0.5 in Australia. Median time from symptom onset to diagnosis was 5.5 months (interquartile range, 1.4-15 months). Complicated CD (stricturing, penetrating, or perianal disease) was more common in Asia than Australia (52% vs 24%; P = .001), and a family history of IBD was less common in Asia (3% vs 17%; P < .001).
CONCLUSIONS: We performed a large-scale population-based study and found that although the incidence of IBD varies throughout Asia, it is still lower than in the West. IBD can be as severe or more severe in Asia than in the West. The emergence of IBD in Asia will result in the need for specific health care resources, and offers a unique opportunity to study etiologic factors in developing nations.