In South Korea, surveillance of antimicrobial drug resistance in Neisseria gonorrhoeae is extremely limited. We describe the emergence and subsequent national spread of N. gonorrhoeae strains with mosaic penA alleles associated with decreased susceptibility and resistance to extended-spectrum cephalosporins. From 2012 through 2017, the proportion of mosaic penA alleles in gonococcal - positive nucleic acid amplification test (NAAT) specimens across South Korea increased from 1.1% to 23.9%. Gonococcal strains with mosaic penA alleles emerged in the international hubs of Seoul in Gyeonggi Province and Busan in South Gyeongsang Province and subsequently spread across South Korea. Most common was mosaic penA- 10.001 (n = 572 isolates; 94.7%), which is associated with cefixime resistance. We also identified mosaic penA- 34.001 and penA -60.001, both of which are associated with multidrug-resistant gonococcal strains and spread of cefixime and ceftriaxone resistance. Implementation of molecular resistance prediction from N. gonorrhoeae –positive nucleic acid amplification test specimens is imperative in South Korea and internationally.

Background:The increasing incidence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) has become a serious worldwide problem. However, there is insufficient data regarding the current status of MDR-TB and XDR-TB in Korea. This study examined the recent status of MDR-and XDR-TB using the data from 7 laboratories, in which almost all drug susceptibility tests (DST) for Mycobacterium tuberculosis were performed. Methods: The patients' identification data and DST results were collected from all 7 laboratories from 2001 to 2006 and the number of patients with MDR-TB and XDR-TB were calculated. Results: The number of DSTs was 140,638 for 6 years with an increasing incidence each year (p＜0.001). The number of DST with MDR results was 18,510 and personal identifying information was obtained in 16,640 (89.9%) tests. The number of MDR-TB patients from 2001 to 2006 was 2,329, 2,496, 2,374, 2,300, 2,354, and 2,178, respectively, when counting the duplications in a year as one patient. The number of MDR-TB patients when counting the duplications in 6 years as one patient was 2,281, 1,977, 1,620, 1,446, 1,512, and 1,373, respectively. When the same method was adopted, the number of XDR-TB patients was 191, 238, 282, 260, 272, and 264, respectively, and 189, 150, 130, 90, 122, and 110 patients, respectively. Conclusion: Despite the national efforts to control TB, there are still a large number of MDR-and XDR-TB patients in Korea.

Background : Fecal occult blood tests (FOBTs) have been widely used as a means of colorectal cancer screening. Automated FOBTs using immunologic principles have the advantages such as quantitation, high specificity, and high throughput. We evaluated a newly-introduced automated FOBT analyzer, OC-SENSOR neo (OC neo) (Eiken Chemical Co., Japan).Methods : The precision, linearity, and carry-over rate of OC neo were assessed with specimens prepared in accordance with the guidelines of CLSI. We performed a parallel test between OC neo and OC-SENSOR I (OC I) (Eiken Chemical Co.) using 300 consecutive stool specimens and 60 OC I-positive specimens. The results were analyzed with SPSS version 13.0 (SPSS Inc., USA).Results : The coefficients of variation (CV) of within-run, between-run, and between-day using OCControl L (Eiken Chemical Co.) of ca. 150 ng/mL were 3.5-7.8%, 4.5-8.8% and 4.9-5.0%, respectively. The linear regression coefficient and carry-over rate with the range of 67.8-939.4 ng/mL were 0.9998 (P<0.001), and 0.1%, respectively. Correlation coefficient between OC neo and OC I was R