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The interest inIn April 2018, about 50 questions on the current status of CDI assays and details on implementation and perceptions were written, and a survey questionnaire was administered to laboratory medicine specialists in 200 institutions.One-hundred and fifty institutions responded to the questionnaire, of which 90 (60.0%) including one commercial laboratory, performed CDI assays. The toxin AB enzyme immunoassay (toxin AB EIA), nucleic acid amplification test (NAAT), andThis study provides useful evidence on the current status of CDI laboratory diagnosis in Korea as well as on items that require improvement and is thought to aid in standardizing and improving the CDI laboratory diagnosis in Korea.

Central line-associated bloodstream infections (CLABSIs) are preventable health care-associated infections that can lead to increased mortality. Therefore, we investigated trends in CLABSI rates, and the factors associated with changing trends over a 10-year period using the Korean National Healthcare-associated Infections Surveillance System (KONIS).We investigated annual CLABSI rates from 2006 to 2015 in 190 KONIS-participating intensive care units (ICUs) from 107 participating hospitals. We collected data associated with hospital and ICU characteristics and analyzed trends using generalized autoregressive moving average models.The CLABSI pooled mean rate decreased from 3.40 in 2006 to 2.20 in 2015 (per 1,000 catheter-days). The trend analysis also showed a significant decreasing trend in CLABSI rates in unadjusted models (annual increase, -0.137; P.001). After adjusting for hospital and ICU characteristics, significant decreasing trends were identified (annual increase, -0.109; P.001). However, there were no significant changes in subgroups with non-university-affiliated hospitals, hospitals in metropolitan areas near Seoul, small hospitals (300-699 beds), or surgical ICUs.In South Korea, CLABSI rates have shown significant reductions in the past 10 years with participation in the KONIS. However, CLABSI rates may be reduced by encouraging more hospitals to participate in the KONIS and by improved policy support for hospitals lacking infection control resources.

We performed a point seroprevalence survey of measles among healthcare workers (HCWs) at two Korean teaching hospitals in 2019. A total of 2,830 HCWs underwent an antibody test. The overall seropositivity of measles was 93.1%. The seroprevalence of measles was lowest in HCWs aged 20 - 24 years (81.2%), followed by those aged 25 - 29 years (90.1%). The rates of anti-measles IgG positivity were significantly different between the two hospitals (97.0% vs. 89.4%, P

Background National surveillance data should be validated to identify data quality issues. This study tested the validity of healthcare-associated infection (HAI) data in the Korean National Healthcare-associated Infections Surveillance System (KONIS), intensive care unit (ICU) module. Methods The validation process consisted of external (EV) and internal (IV) validation phases. For the 10 hospitals that were selected based on the HAI rate, among the 193 participating hospitals between July 2016 and June 2017, both EV and IV were performed. For the EV, the validation team reviewed 295 medical records of 60 patients with reported HAIs, including 20 urinary tract infections (UTIs), 27 bloodstream infections (BSIs), and 13 cases of pneumonia (PNEU), and 235 patients with no reported HAI during 1-day visits conducted in November and December 2017. The reviewer’s diagnosis of HAI was regarded as the reference standard. IV was conducted by the staff of each hospital and evaluated whether UTI or BSI were present. Primary IV was performed for 279 patients who were subject to EV. Secondary IV was performed on 203 patients in another 11 selected participating hospitals that did not report HAIs to KONIS during the 1-year study period. Results In the EV, the diagnosis of UTI in the participating hospitals had a sensitivity of 72.0% and specificity of 99.3%. The sensitivity of BSI and PNEU was 63.2% and 70.6%, respectively, and specificity was 98.8% and 99.6%. The agreement (kappa) between the EV and primary IV was significant, with κ = 0.754 for UTI and κ = 0.674 for BSI. The results of the secondary IV showed that the hospitals that had no reports of HAI had few hospital beds and performed few blood or urine culture tests. In the secondary IV, eight UTIs and three BSIs were newly diagnosed in three hospitals, respectively. The reasons for not reporting the HAIs were presumed to be a lack of understanding of the surveillance standards and fear of the disadvantages of disclosing the HAI. Conclusion This study shows the need for ongoing validation and continuous training of surveillance personnel to maintain the accuracy of surveillance data. We also confirmed that IV can be used as an alternative monitoring method to examine validity and accuracy. Disclosures All authors: No reported disclosures.

The prevalence of toxigenic Clostridium difficile in Korea has been reported to be approximately 60–80 %. Although the prevalence of the tcdA−tcdB+ C. difficile strain was less then 5 % prior to the year 2000, it has become an emerging nosocomial pathogen in Korea. Therefore, we have attempted to determine the multicentre nationwide prevalence of tcdA+tcdB+ and tcdA−tcdB+ C. difficile for epidemiological purposes. C. difficile strains (n=724, 30 from 2000, 80 from 2001, 74 from 2002, 76 from 2003, 179 from 2004, 285 from 2005) were obtained retrospectively from January 2000 to December 2005 from in-patients at 6 hospitals, all of whom were suspected of having C. difficile-associated disease (CDAD), colitis or pseudomembranous colitis. The numbers of participating hospitals varied yearly (1 in 2000, 2 in 2001–2003, 3 in 2004, 5 in 2005). The hospitals were located in Seoul (n=4), Kyunggi Province (n=1) and Busan (n=1), Korea. PCR assays for tcdA and tcdB genes were conducted using 724 unduplicated C. difficile isolates. The mean prevalence of tcdA+tcdB+ and tcdA−tcdB+ C. difficile strains over the 6 years was 51.8 % (38.4–59.3 %) and 25.8 %(10–56.0 %), respectively. The mean prevalence of tcdA−tcdB+ C. difficile strains was less than 7 % until 2002, but began to increase in 2003 (13.2 %) and achieved a peak in 2004 (50.3 %). In 2005, the mean prevalence of tcdA+tcdB+ and tcdA−tcdB+ C. difficile strains was 47.7 % (30.9–60.3 %) and 27.0 % (17.6–54.8 %), respectively. This nationwide epidemiological study showed that tcdA−tcdB+ C. difficile strains have already spread extensively throughout Korea, and our results provide basic data regarding the controversies currently surrounding the toxigenicity of tcdA−tcdB+ C. difficile. The use of enzyme immunoassays capable of detecting both TcdA and TcdB is strongly recommended for the diagnosis of CDAD in microbiology laboratories, in order to control the spread of the tcdA−tcdB+ strains of C. difficile.

We studied the seroprevalence of HBsAg, anti-HBs and anti-HBc and the vaccination histories among health care workers (HCWs) at a large suburban referral hospital in Korea. The purpose of this study was to determine the immune status of HCWs against hepatitis B virus and we also wanted to prepare a practical guideline to protect HCWs from occupational exposure. During December, 2003, 571 HCWs (56 physicians, 289 nurses, 113 technicians and 113 aid-nurses) aged between 21 and 74 yr were included in the surveillance. The positive rates of HBsAg and anti-HBs were 2.4% (14/571) and 76.9% (439/571), respectively. The positive rate of anti-HBs was lower in the physician group, and this was associated with the male gender and older age. Of the 439 anti-HBs positive cases, 320 cases (73.1%) were anti-HBc negative and this was significantly associated with a past history of HBV vaccination. The distribution of the anti-HBs levels was not associated with age (except for HCWs in their sixties), gender or occupation. Our study revealed that the seroprevalence rates of HBsAg and anti-HBs in HCWs in Korea were not different from those of the general population. Based on this surveillance, we can make reasonable decisions in case of occupational exposure to hepatitis B virus.

The mechanism(s) of cystic fibrosis transmembrane conductance regulator (CFTR) trafficking from the endoplasmic reticulum (ER) through the Golgi apparatus, the step impaired in individuals afflicted with the prevalent CFTR-ΔF508 mutation leading to cystic fibrosis, is largely unknown. Recent morphological observations suggested that CFTR is largely absent from the Golgi in situ (Bannykh, S. I., Bannykh, G. I., Fish, K. N., Moyer, B. D., Riordan, J. R., and Balch, W. E. (2000)Traffic 1, 852–870), raising the possibility of a novel trafficking pathway through the early secretory pathway. We now report that export of CFTR from the ER is regulated by the conventional coat protein complex II (COPII) in all cell types tested. Remarkably, in a cell type-specific manner, processing of CFTR from the core-glycosylated (band B) ER form to the complex-glycosylated (band C) isoform followed a non-conventional pathway that was insensitive to dominant negative Arf1, Rab1a/Rab2 GTPases, or the SNApREceptor (SNARE) component syntaxin 5, all of which block the conventional trafficking pathway from the ER to the Golgi. Moreover, CFTR transport through the non-conventional pathway was potently blocked by overexpression of the late endosomal target-SNARE syntaxin 13, suggesting that recycling through a late Golgi/endosomal system was a prerequisite for CFTR maturation. We conclude that CFTR transport in the early secretory pathway can involve a novel pathway between the ER and late Golgi/endosomal compartments that may influence developmental expression of CFTR on the cell surface in polarized epithelial cells.

Atherosclerosis is characterized by a chronic inflammatory disease, and chemokines play an important role in both initiation and progression of atherosclerosis development. Leukotactin-1 (Lkn-1/CCL15), a new member of the human CC chemokine family, is a potent chemoattractant for leukocytes. Our previous study has demonstrated that Lkn-1/CCL15 plays a role in the initiation of atherosclerosis, however, little is currently known whether Lkn-1/CCL15 is associated with the progression of atherosclerosis. Matrix metalloproteinases (MMPs) in human coronary atherosclerotic lesions play a crucial role in the progression of atherosclerosis by altering the vulnerability of plaque rupture. In the present study, we examined whether Lkn-1/CCL15 modulates MMP-9 release, which is a prevalent form expressed by activated macrophages and foam cells. Human THP-1 monocytic cells and/or human peripheral blood monocytes (PBMC) were treated with phorbol myristate acetate to induce their differentiation into macrophages. Foam cells were prepared by the treatment of THP-1 macrophages with human oxidized LDL. The macrophages and foam cells were treated with Lkn-1/CCL15, and the levels of MMP-9 release were measured by Gelatin Zymography. Lkn-1/CCL15 significantly enhanced the levels of MMP-9 protein secretion from THP-1 monocytic cells-derived macrophages, human PBMC-derived macrophages, as well as macrophage-derived foam cell in a dose dependent manner. Our data suggest that the action of Lkn-1/CCL15 on macrophages and foam cells to release MMP-9 may contribute to plaque destabilization in the progression of atherosclerosis.

Sixty percent to 80% of Clostridium difficile isolates in Korea have been reported to be toxigenic. However, over 1 year, we encountered a high number of tcdA-tcB+ strains associated with pseudomembranous colitis (PMC). C. difficile was isolated from 224 of 471 specimens (47.6%) from 371 patients. A subset of the culture-positive specimens (n = 106), containing no duplicate cases, was randomly selected for tcdA and tcdB polymerase chain reaction (PCR) assays. PCR results showed that tcdA+tcdB+ and tcdA-tcdB+ strains accounted for 39.6% (42/106) and 50.9% (54/106), respectively. Endoscopy, performed on 55/106 patients, revealed 29 with PMC, 5 with colitis, 14 with other colon diseases, and 7 normal cases. Among the 29 PMC cases, 21 (72.4%) were associated with tcdA-tcdB+ strains (P = 0.0016). These results revealed the possible emergence of tcdA-tcdB+ C. difficile strains in Korea, and these variant strains could evoke a higher rate of PMC than tcdA+tcdB+ strains.

A novel subtype of influenza A virus called pandemic (H1N1) 2009 virus showed global outbreaks in 2009. Previous studies reported that gastrointestinal symptoms such as diarrhea, vomiting, and abdominal pain were frequent in patients with pandemic (H1N1) 2009 virus infection (3, 4, 5). However, the frequency of viral shedding in this pandemic (H1N1) 2009 virus infection was not well known. We recovered pandemic (H1N1) 2009 virus from stools of hospitalized H1N1-positive patients. From 10 November to 31 December 2009, 1,774 patients were diagnosed as having pandemic (H1N1) 2009 virus infections by real-time reverse transcription-PCR (RT-PCR) from nasopharyngeal swab samples in a tertiary-care hospital located in Seoul, South Korea. Among them, 96 patients required hospitalization due to progression to pneumonia or febrile convulsion, acute gastroenteritis, or underlying illnesses. Their stool samples were requested to be collected at admission, irrespective of gastrointestinal symptoms. A total of 65 patients submitted their stool samples at 0 to 8 days after the onset of flu symptoms and were included in this study (Table ​(Table1).1). Twelve patients (18.5%) complained of diarrhea during the hospitalization period. All of them were self-limited, and only one patient showed a pathogen, Salmonella group B, in routine stool cultures. This study was approved by the Sanggye Paik Hospital institutional review board. TABLE 1. Demographic characteristics categorized by the presence of viral RNA in stools among the study population hospitalized with pandemic (H1N1) 2009 virus Viral RNA in stool was isolated using the QIAamp virus RNA minikit (Qiagen, Crawley, United Kingdom). Pandemic (H1N1) 2009 virus was detected by two kinds of RT-PCR kits, the Anyplex FluA new H1N1 kit (SeeGene, Seoul, South Korea) and TaqMan Influenza A MGB assays (Applied Biosystems). Pandemic (H1N1) 2009 virus was recovered from stools of 16 patients (24.6%). Nine of them (56.3%) did not complain of any gastrointestinal symptoms during hospitalization. Only 4 patients simultaneously presented diarrhea and fecal excretion of pandemic (H1N1) 2009 virus. Comparing stool pandemic (H1N1) 2009-positive and -negative groups, no difference of frequency was noticed for diarrhea (P = 0.683), nausea (P = 0.746), vomiting (P = 0.898), and abdominal pain (P = 0.977) (Table ​(Table11). The clinical significance and pathophysiology of fecal influenza A virus excretion are not yet clear (1, 9). However, avian influenza A (H5N1) virus has been known to cause severe gastrointestinal manifestations and to replicate in human intestinal tissues (2, 7, 8). To et al. detected pandemic (H1N1) 2009 virus in stool from 4 of 9 patients with positive viral culture from the specimen with the highest viral load (6). This finding suggested the fecal shedding of viable pandemic (H1N1) 2009 virions. In this study, fecal excretion of pandemic (H1N1) 2009 virus was not correlated with the presence of gastrointestinal symptoms as described for avian influenza A (H5N1) virus (7). This study has some limitations: outpatients were not included and virus cultures and quantifications were not performed. However, our data show that considerable numbers of patients shed pandemic (H1N1) 2009 virus in their stool, even in the absence of diarrhea. The frequent detection of fecal pandemic (H1N1) 2009 virus excretion deserves attention in the study of infection control to prevent viral dissemination.

Angiogenesis, the recruitment of new blood vessels is a crucial mechanism required for both tumor growth and metastasis. Vascular endothelial growth factor (VEGF) and its receptors, particularly VEGF receptor 2 (VEGFR2, or kinase insert domain-containing receptor, KDR), play a critical role in tumor-associated angiogenesis. Monoclonal antibodies (mAb), due to their high specificity towards a given target, represent a unique class of novel therapeutics as angiogenesis inhibitors. We developed TTAC-0001, anti-KDR antibody from a fully human naïve single chain variable fragment (ScFv) phage library. Interestingly, TTAC-0001 displayed cross reactivity against murine homologue, Flk-1, which allows us to evaluate the anti-tumor efficacy in various in vivo models. TTAC-0001 inhibits VEGF-mediated proliferation and migration. In HUVEC, TTAC-0001 inhibited the phosphorylation of VEGFR2/KDR and ERK mediated by VEGF. TTAC-0001 inhibited VEGF-mediated sprouting endothelial cells from rat aortic rings and showed a potent anti-angiogenic activity in VEGF-mediated matrigel model in nude mice. Further in vivo anti-tumor efficacy of TTAC-0001 was seen in the xenografts of A549 (lung) and HCT116 (colorectal) human cancer. These changes were accompanied by the inhibition of microvessel density and induction of apoptosis in the tumors. In summary, our data indicates that TTAC-0001 blocks the binding of VEGF to VEGFR2/KDR and inhibits VEGFR-induced angiogenesis. Therefore, this data strongly supports for the further development of TTAC-0001 as an anti-cancer agent (This study was supported by grants of the Korea Healthcare technology R&D Project, Ministry for Health & Welfare Affairs (A092255 and A040016) and Advanced Medi-cluster R&D Project, Daejeon TechnoPark, Republic of Korea). Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4244. doi:10.1158/1538-7445.AM2011-4244

An epidermoid cyst located in the true intracavernous sinus is extremely rare. A 22-year-old man presented with right ophthalmoplegia that had developed 3 years previously. The computed tomography (CT) and magnetic resonance (MR) images demonstrated a mass in the right cavernous sinus. The mass was a non-enhancing cystic lesion with a focal high density portion seen on the CT scan. The lesion displayed a markedly hyperintense signal on the diffusion-weighted images (DWI) and a heterogeneously hyperintense signal on the constructive interference in the steady state (CISS) images, which was all consistent with an epidermoid cyst. On the operation field, the mass was noted to be a true intracavernous sinus lesion, and it was histopathologically confirmed to be an epidermoid cyst.

Background: The aim of this study is to clarify the epidemiology of swine-origin influenza A (H1N1) virus 2009 (S-OIV) during the first month of outbreak at one of influenza clinic in Seoul, Korea. Methods: We documented the epidemiologic and clinical features of S-OIV-confirmed cases who visited a university hospital in Northeastern Seoul between August 21 and September 20, 2009. Nasopharyngeal swab of patients with acute febrile respiratory illnesses were evaluated with rapid influenza antigen tests and multiplex RT-PCR for S-OIV and seasonal influenza A. Results: A total of 5,322 patients with acute febrile respiratory illnesses were identified at our influenza clinic for the study period. S-OIV was confirmed in 309 patients by RT-PCR. The patients ranged from 2 months to 61 years of age and 189 patients (61.2%) were teenagers. Eighty-one patients had known contact with S-OIV-confirmed patients in schools (N=61), households (N=15), and healthcare facilities (N=3). Frequent symptoms were fever (94.5%), cough (73.1%), sore throat (52.1%), and rhinorrhea (50.5%). Gastrointestinal symptoms were also present in 10 patients (4.9%). Ten patients (4.9%) required hospitalizations. Seventy patients (22.7%) could not take oseltamivir at the first visits, however, all of them recovered without complication. Rapid antigen tests showed the sensitivity of 44.4% (130/294). Patients with positive antigen tests, compared with negative antigen tests, showed higher frequencies of rhinorrhea (60.8% vs 43.3%, P=0.004) and stuffy nose (33.8% vs 20.1%, P=0.012). Conclusion: S-OIV infections spread predominately in school-aged children during the early accelerating phase of the outbreak. Rapid influenza antigen tests were correlated with nasal discharge and obstruction. (Korean J Clin Microbiol 2010;13:103-108)

Purpose: We wanted to evaluate the usefulness of helical CT, along with histopathologic correlation, for the preoperative evaluation of small advanced gastric cancers (AGCs) mimicking as early gastric cancer (EGCs) at endoscopy. Materials and Methods: From February 2001 to September 2004, we retrospectively reviewed 17 patients with pathologically proven small AGCs that were misinterpreted as EGCs at endoscopy. The preoperative helical CT findings were prospectively analyzed and the CT staging was compared with the pathologic staging that was based on the depth of tumor invasion and status of lymph node metastasis, according to the TNM classification. Results: The endoscopic findings of the 17 AGCs misinterpreted as EGCs were type IIc (n=7), IIb+IIc (n=3), IIa+IIc (n=3), IIa+IIb (n=1), and III (n=3). The mean size of the AGCs on the gross specimen was 2.8 cm (range: 1.2 cm-5 cm). Helical CT clearly depicted the depth of tumor invasion by the marked transmural enhancement or the reticular strands in the exraserosal fat. Preoperative helical CT detected all 17 AGCs (100%) and it correctly diagnosed then as AGCs in 15 (88%) of 17 cases. CT staging for the T category correctly staged 12 cases (71%), it understaged four cases and it overstaged one case. Regional lymph node metastasis was positive in 11 (64%) of 17 cases on the pathologic examination. The CT staging for the N category correctly staged 10 (59%) of 17 cases, it understaged four cases, and it overstaged three cases. Conclusion: Preoperative helical CT correctly diagnosed small AGCs mimicking as EGCs at endoscopy. Our results show that helical CT can be useful for the decision-making during the treatment planning for those patients with gastric cancer in which the endoscopic distinction between EGC and AGC is difficult.