Norovirus (NoV) genogroups I and II are frequently recognized as the main causes of acute gastroenteritis and outbreaks of non-bacterial foodborne diseases. Furthermore, variants and recombinant strains of this virus are continuously emerging worldwide. The aim of this study was to identify NoV strains and to investigate and characterize rare genotypes. Stool samples (n = 500) were collected from patients with symptoms of acute gastroenteritis in Korea between December 2004 and November 2007. For analysis of the samples, rapid genotype screening was performed using reverse transcriptase-polymerase chain reaction. Full sequencing, using a newly designed set of 12 primers, revealed GII-12/13 strain. The partial sequence of GII-12/13 strain was compared with published NoV (GII-1 - 14) sequences targeting RdRp and capsid regions using phylogenetic analysis with the SimPlot program, which could evaluate recombination breakpoints. SimPlot analysis was also performed with the strain GII-12/Gifu-96/JPN (AB045603) for the RdRp region and with GII-13/G5175B-83/AUS(DQ379714) for the capsid region. NoV was detected in 19 of the 500 stool samples (3.8%). Genogroup GII-4 was found most frequently (n = 9, 1.8%), followed by GII-3 (n = 4, 0.8%), GII-6 (n = 3, 0.6%), GI-6 (n = 2, 0.4%), and GII-12/13 (n = 1, 0.2%). Importantly, we identified a novel NoV recombinant strain, C9-439 (KF289337), indicating potential risks, which suggested that, recombination occurred in the region between open reading frames 1 and 2 of the GII-12/13 strain and that breakpoints occurred in the polymerase region.

Severe fever with thrombocytopenia syndrome (SFTS) is being reported annually in South Korea since its first detection there in 2010. The causal agent is a negative-strand RNA virus 80-100 nm in diameter. It causes fever, thrombocytopenia, leukocytopenia, gastrointestinal symptoms, and neural symptoms. The mortality rate of SFTS was 32.6% among 172 cases reported from 2012 to 2015 in South Korea. Thus, is necessary to develop an effective diagnostic method that selectively identifies the isolates circulating in South Korea. The real-time reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay is a simple, rapid, and sensitive approach for molecular diagnosis. Here, we designed novel primers for this assay and found that the technique had very high specificity, sensitivity, and efficiency. This real-time RT-LAMP approach using the novel primers developed herein can be applied for early diagnosis of SFTSV strains in South Korea to reduce the mortality rate of SFTS.

The use of dual antiplatelet drugs and a higher aPTT can lead to an increased risk of post-procedural vascular complications. Therefore, manual compression should be applied cautiously after the correction of coagulopathy factors such as activated clotting time (ACT), aPTT, and platelets.

Schwannoma is a peripheral nerve sheath tumour that largely originates from the posterior mediastinum. Schwannoma arising in mediastinal lymph node is extremely rare. A 53‐year‐old female was referred to our hospital for the evaluation of enlarged mediastinal lymph node. Computed tomography scan revealed a non‐enhancing soft tissue mass at Rt. paratracheal area. Endobronchial ultrasound showed a well‐defined round‐shaped lymph node and transbronchial needle aspiration was performed from this lymph node. Pathologic findings revealed spindle cells with strong S100 positivity. Complete surgical excision was done. We report a rare case of schwannoma arising in mediastinal lymph node diagnosed by endobronchial ultrasound.

Norovirus, Rotavirus group A, the Hepatitis A virus, and Coxsackievirus are all common causes of gastroenteritis. Conventional diagnoses of these causative agents are based on antigen detection and electron microscopy. To improve the diagnostic potential for viral gastroenteritis, internally controlled multiplex real-time polymerase chain reaction (PCR) methods have been recently developed. In this study, individual real-time PCRs were developed and optimized for specific detections of Norovirus genogroup I, Norovirus genogroup II, Rotavirus group A, the Hepatitis A virus, and Coxsackievirus group B1. Subsequently, individual PCRs were combined with multiplex PCR reactions. In general, multiplex real-time PCR assays showed comparable sensitivities and specificities with individual assays. A retrospective clinical evaluation showed increased pathogen detection in 29% of samples using conventional PCR methods. Prospective clinical evaluations were detected in 123 of the 227 (54%) total samples used in the multiplex real-time PCR analysis. The Norovirus genogroup II was found most frequently (23%), followed by Rotavirus (20%), the Hepatitis A virus (4.5%), Coxsackievirus (3.5%), and Norovirus genogroup I (2.6%). Internally controlled multiplex real-time PCR assays for the simultaneous detection of Rotavirus, Coxsackievirus group B, the Hepatitis A virus, and Norovirus genogroups I and II showed significant improvement in the diagnosis of viral gastroenteritis.

Hepatitis A virus is known to cause acute hepatitis and has significant implications for public health throughout the world. In the Republic of Korea, the number of patients with hepatitis A virus infection has been increasing rapidly since 2006. In this study, the Kor-HAV-F strain was identified as subgenotype IIIA by RT-PCR, and its identity was confirmed by nucleotide sequencing and alignment analysis. Moreover, detailed phylogenetic analysis indicated that the Kor-HAV-F strain clustered into subgenotype IIIA, including strains isolated in Japan, Norway, and India. The entire amino acid sequence of the VP1 and 2A regions was compared with that of the reference strains isolated in various countries. We found 2 amino acid changes (T168A and L96P, resp.) in the VP1 and 2A regions, which had not been found in any other hepatitis A virus strain. To our knowledge, this study is the first to report the full-length sequence of a hepatitis A virus isolated in the Republic of Korea.

Norovirus is one of the major causes of non-bacterial gastroenteritis in humans. The aim of this study was to analyze the amino acid variation of open reading frame 2 of GII.4 variants in South Korea during the period from November 2006 to December 2012. Sixty-nine complete nucleotide sequences of open reading frame 2 were obtained from 113 GII.4 strains. The GII.4 2006b variants were detected predominantly between 2006 and 2009; however, new GII.4 variants, which were termed the 2010 variant and the 2012 variant, emerged in 2010 and 2012, respectively. The number of GII.4 2006b variants steadily decreased until 2012, whereas the number of gastroenteritis cases caused by the new variants increased between 2010 and 2012. The amino acid sequence in the ORF2 region obtained in this study was compared with other GII.4 variants isolated in various countries. Amino acid variations were observed primarily at epitope sites and the surrounding regions. Amino acids 294, 359, 393, and 413 of the P2 subdomain were the most variable sites among the GII.4 variants. The information in this study can be useful in basic research to predict the emergence and determine the genetic functions of new GII.4 variants.

Background The diagnosis of tuberculous pericarditis is difficult to set, not only for its non‐specific clinical presentation, but also for the lack of useful diagnostic tests. We comprehensively evaluate the overall diagnostic accuracy of Interferon‐gamma release assays (IGRA) upon tuberculous pericarditis by meta‐analysis. Methods We searched PubMed, Embase and Cochrane Library database from the earliest available date of indexing through April 30, 2019. The study quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS2) checklist. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR−) and constructed summary receiver operating characteristic curves parameters. Results Across six results from five studies (415 patients), the pooled sensitivity for IGRA methods was 0.94 (95% confidence interval [CI]; 0.87‐0.98) with heterogeneity (χ2 = 69.9, P = .01) and a pooled specificity of 0.94 (95% CI; 0.75‐0.94) without heterogeneity (χ2 = 41.1, P = .13). Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 16.8 (95% CI; 8.0‐35.4) and negative likelihood ratio (LR−) of 0.06 (95% CI; 0.03‐0.13). The pooled diagnostic odds ratio was 278 (95% CI; 114‐6806). Conclusions Interferon‐gamma release assays demonstrated good sensitivity and specificity for diagnosis of tuberculous pericarditis. At present, the literature regarding remains the use of IGRA for diagnosis of tuberculous pericarditis still limited; thus, further large multicenter studies would be necessary to substantiate the diagnostic accuracy of IGRA test for the diagnosis of tuberculous pericarditis.