Epidemiology of inflammatory bowel disease in the Songpa-Kangdong district, Seoul, Korea, 1986-2005: a KASID study.

BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) are considered rare diseases in developing countries. We have evaluated the incidence and prevalence of CD and UC over time in a district of Seoul, Korea. METHODS: A population-based study was performed from 1986 to 2005 in the Songpa-Kangdong district of Seoul. To recruit patients as completely as possible, multiple information sources, including all medical facilities in the study area and 3 referral centers nearby but outside the study area, were used. RESULTS: During the 20-year study period, 138 incident cases of CD (102 men, 36 women) and 341 incident cases of UC (170 men, 171 women) were identified. For the 20-year period, the adjusted mean annual incidence rates of CD and UC per 100,000 inhabitants were 0.53 (95% CI 0.44-0.62) and 1.51 (95% CI 1.34-1.67), respectively. When analyzed by 5-year intervals, the mean annual incidence rates of CD and UC increased significantly, from 0.05 and 0.34 per 100,000 inhabitants, respectively, in 1986-1990 to 1.34 and 3.08 per 100,000 inhabitants, respectively, in 2001-2005. The adjusted prevalence rates of CD and UC per 100,000 inhabitants on December 31, 2005, were 11.24 (95% CI 9.29-13.18) and 30.87 (95% CI 27.47-34.27), respectively. CONCLUSIONS: The incidence and prevalence of CD and UC in Seoul, Korea, are still low compared with those in Western countries, but are rapidly increasing.

Familial occurrence of inflammatory bowel disease in Korea.

BACKGROUND: Little information is available about the familial aggregation of inflammatory bowel disease (IBD) in Asian populations. We therefore determined the risk of familial aggregation of IBD among first-degree relatives of patients with ulcerative colitis (UC) or Crohn's disease (CD) in an ethnically distinct Korean population. METHODS: Familial aggregation of IBD was evaluated in terms of family history, prevalence, lifetime risk, and population relative risk in first-degree relatives of 1440 unrelated patients with UC (n = 1043) or CD (n = 397). RESULTS: A positive first-degree family history of IBD was observed in 27 probands (1.88%): 21 of 1043 (2.01%) with UC and 6 of 397 (1.51%) with CD. The crude prevalence of IBD in first-degree relatives of probands with IBD was 0.31%. The lifetime risk of IBD was 0.54% in all first-degree relatives of IBD probands, 0.52% in UC probands, and 0.67% in CD probands, with overall lifetime relative risks of 0.12% in parents, 0.79% in siblings, and 1.43% in offspring. The age- and sex-adjusted population relative risk of IBD was 13.8 in first-degree relatives of probands with IBD. CONCLUSIONS: Although a positive family history, prevalence, and lifetime risk of IBD among first-degree relatives of Korean IBD patients are much lower than among relatives of Western patients, the population relative risk in first-degree relatives is about equal in Koreans and Westerners. This finding indicates that a positive family history is an important risk factor for IBD in Koreans and in Westerners.

Characteristics of Epstein-Barr virus isolated from the malignant lymphomas in Korea.

Epstein-Barr virus (EBV) is a common herpes virus linked to a variety of human neoplasms. In this study, the EBV detection was identified with the paraffin-embedded tissues from 62 non-Hodgkin's lymphomas, 20 Hodgkin's lymphomas, and 48 non-neoplastic tonsils, using PCR for EBNA-1 and EBER-1 mRNA in situ hybridization for EBER-1 mRNA. The isolates were analyzed for type 1/2, variants C/D and F/f, and LMP-1 30 bp deletion. EBV was isolated in 31 of 48 (66%) non-neoplastic tonsils, 24 of 42 (57%) B cell lymphomas, in 15 of 20 (75%) T cell lymphomas, and 17 of 20 (85%) Hodgkin's lymphomas. These viruses were classified as type 1 for 81% of non-neoplastic tonsils, 95% of B cell lymphomas, 93% of T cell lymphomas, and 73% of Hodgkin's diseases. Both type 1 and 2 viruses were isolated in one non-neoplastic tonsil and 3 Hodgkin's diseases. Type C virus was predominant in non-neoplastic tonsils (77%) and B cell lymphomas (75%), while type D virus was common in T cell lymphomas (71%) and Hodgkin's diseases (73%) (P < 0.05). Majority of the viruses detected in non-neoplastic tonsils (93%) and malignant lymphomas (91%) were "F" prototype. LMP-1 30 bp deletion was found in high frequency in both non-neoplastic tonsils (92%) and malignant lymphomas (86%). In conclusion, most of EBV found in Korea was type 1, and "DF" genotype was more frequent in T cell lymphomas and Hodgkin's diseases than in non-neoplastic tonsils and B cell lymphomas. LMP-1 30 bp deletion did not seem to be associated with malignant lymphomas.