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Salmonella is one of the major causes of food-borne infections. We investigated the serotype distribution and antimicrobial resistance of Salmonella isolates collected in Korea between January 2016 and December 2017. In total, 669 Salmonella isolates were collected from clinical specimens at 19 university hospitals. Serotyping was performed according to the Kauffmann-White scheme, and antimicrobial susceptibility was tested using Sensititre EUVSEC plates or disk diffusion. Among the strains, C (39.8%) and B (36.6%) were the most prevalent serogroups. In total, 51 serotypes were identified, and common serotypes were S. enterica serovar I 4,[5],12:i:- (16.7%), S. Enteritidis (16.1%), S. Bareilly (14.6%), S. Typhimurium (9.9%), and S. Infantis (6.9%). The resistance rates to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole were 32.6%, 12.1%, and 8.4%, respectively. The resistance rates to cefotaxime and ciprofloxacin were 8.1% and 3.0%, respectively, while 5.4% were multidrug-resistant. S. enterica serovar I 4,[5],12:i:- and S. Enteritidis were highly prevalent, and there was an increase in rare serotypes. Multidrug resistance and ciprofloxacin resistance were highly prevalent. Periodic investigations of Salmonella serotypes and antimicrobial resistance are needed.

Next-generation sequencing (NGS) has been implemented as a rapid and cost-effective BRCA1/2 test strategy. The Oncomine™ BRCA Research Assay is an NGS-based tool for simultaneous detection of small-scale mutations and large genomic rearrangements (LGRs). We evaluated this NGS assay using different versions of Ion Reporter™ (IR) software.A total of 258 patients with breast, ovarian, primary peritoneal, and fallopian tube cancer, or a family history thereof, were enrolled in the study. The NGS assay was implemented for all samples, and the results were compared with those of Sanger sequencing and MLPA.All small-scale variations in Sanger sequencing were successfully detected by NGS assay. For the detection of LGRs, this assay showed 100% sensitivity from IR v5.10, and the latest version of the software (v5.16) showed the highest sensitivity and specificity.NGS with an appropriately updated workflow proved reliable for comprehensive BRCA1/2 gene testing, including LGR screening, which could facilitate efficient and accurate decision-making regarding treatment.

Background: Salmonella is an important pathogen that causes gastroenteritis and sepsis in humans. Recently, changes in serotype prevalence and an increase in antimicrobial resistance have been reported. This study investigated the distribution of Salmonella serotypes and determined the antimicrobial susceptibility of various strains. Methods: We collected 113 Salmonella isolates other than Salmonella serotype Typhi from 18 university hospitals in 2015. The serotypes were identified by Salmonella antisera O and H according to the Kauffman White scheme. Antimicrobial susceptibility tests for 12 antibiotics were performed using the disk diffusion method or E-test. Results: We identified 22 serotypes. Serotype group B (44.2%) was the most common, followed by groups C (34.5%) and D (21.2%). Salmonella I 4,[5],12:i:- (23.0%), S. Enteritidis (16.8%), and S. Typhimurium (12.4%) were the most common species. Resistance rates for ampicillin, chloramphenicol, ceftriaxone, and trimethoprim/sulfamethoxazole were 46.9%, 18.5%, 8.8%, and 5.3%, respectively. The intermediate resistance rate to ciprofloxacin was 29.2%. Six isolates were extended-spectrum β-lactamase (ESBL) producers, including 5 blaCTX-M-15 and 1 blaCTX-M-55. Conclusion: There have been changes in the serotype prevalence and antimicrobial resistance of Salmonella in Korea, with a high prevalence of CTX-M 15-positive strains. Continuous monitoring of Salmonella serotypes and antimicrobial resistance is warranted. (Ann Clin Microbiol 2019;22:55-60)

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.

Background In Korea, the first community outbreak of coronavirus disease 2019 (COVID-19) occurred in Daegu on February 18, 2020. This study was performed to investigate the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies in healthcare workers (HCWs) at 6 major hospitals in Daegu. Methods Blood specimens of 2,935 HCWs at 6 major hospitals in Daegu from January 2021 to February 2021 were collected. Every specimen was tested for antibody against SARS-CoV-2 using both Elecsys Anti-SARS-CoV-2 electrochemiluminescence immunoassay (Roche Diagnostics, Rotkreuz, Switzerland) and R-FIND COVID-19 IgG/M/A enzyme-linked immunosorbent assay kit (SG medical Inc., Seoul, Korea) as screening tests. If 1 or more of these screening test results was positive, 2 additional antibody tests were performed using Abbott Anti-SARS-CoV-2 IgG assay (Abbott, Abbott Park, IL, USA) and cPass SARS-CoV-2 Neutralization Antibody Detection Kit (GenScript USA Inc., Piscataway, NJ, USA). If 2 or more of the total 4 test results were positive, it was determined as positive for the antibody against SARS-CoV-2. Results According to the criteria of SARS-CoV-2 antibody positivity determination, 12 subjects were determined as positive. The overall positive rate of the SARS-CoV-2 antibody was 0.41% (12/2,935). Of the 12 subjects determined as positive, 7 were diagnosed with COVID-19, and the remaining 5 were nondiagnosed cases of COVID-19. Conclusion In early 2021, the overall seroprevalence of SARS-CoV-2 antibody among HCW located in Daegu was 0.41%, and 0.17% excluding COVID-19 confirmed subjects. These results were not particularly high compared with the general public and were much lower than HCWs in other countries., Graphical Abstract

A newly identified coronavirus, designated as severe acute respiratory syndrome coronavirus 2 (SARS CoV-2), has spread rapidly from its epicenter in China to more than 150 countries across six continents. In this study, we have designed three reverse-transcription loop-mediated isothermal amplification (RT-LAMP) primer sets to detect the RNA-dependent RNA polymerase (RdRP), Envelope (E) and Nucleocapsid protein (N) genes of SARS CoV-2. For one tube reaction, the detection limits for five combination SARS CoV-2 LAMP primer sets (RdRP/E, RdRP/N, E/N, RdRP/E/N and RdRP/N/Internal control (actin beta)) were evaluated with a clinical nasopharyngeal swab sample. Among the five combination, the RdRP/E and RdRP/N/IC multiplex LAMP assays showed low detection limits. The sensitivity and specificity of the RT-LAMP assay were evaluated and compared to that of the widely used Allplex™ 2019-nCoV Assay (Seegene, Inc., Seoul, South Korea) and PowerChek™ 2019-nCoV Real-time PCR kit (Kogenebiotech, Seoul, South Korea) for 130 clinical samples from 91 SARS CoV-2 patients and 162 NP specimens from individuals with (72) and without (90) viral respiratory infections. The multiplex RdRP (FAM)/N (CY5)/IC (Hex) RT-LAMP assay showed comparable sensitivities (RdRP: 93.85%, N: 94.62% and RdRP/N: 96.92%) to that of the Allplex™ 2019-nCoV Assay (100%) and superior to those of PowerChek™ 2019-nCoV Real-time PCR kit (RdRP: 92.31%, E: 93.85% and RdRP/E: 95.38%).

There are reports that pregnant women infected with SARS-CoV-2 not only have increased morbidity but also increased complications and evidence of maternal and fetal vascular malperfusion on placental pathology. This was a retrospective study of pregnant women diagnosed with SARS-CoV-2 infection after March 2020. The results of reverse transcription polymerase chain reaction testing and IgM and IgG antibody testing of the amniotic fluid, cord blood, placenta, and maternal blood were confirmed at delivery. Placentas were evaluated histopathologically. The study included seven pregnant women diagnosed with SARS-CoV-2 infection during pregnancy at a mean gestational age of 14.5 weeks. Out of the seven women, five were infected during the first trimester. The mean gestational age at delivery was 38.4 weeks. The reverse transcription polymerase chain reaction results for maternal plasma, cord blood, placenta, and amniotic fluid were negative and IgG antibodies were detected in maternal plasma and cord blood. On placental pathology, maternal vascular malperfusion was found in only one case, fetal vascular malperfusion in four cases, and inflammatory changes were found in two cases. Pregnancy outcomes for women diagnosed with SARS-CoV-2 infection during early pregnancy are positive and it is likely that maternal antibodies are passed to the fetus, which results in a period of immunity.

Objective We performed small-scale mutation and large genomic rearrangement (LGR) analysis of BRCA1/2 in ovarian cancer patients to determine the prevalence and the characteristics of the mutations. Methods All ovarian cancer patients who visited a single institution between September 2015 and April 2017 were included. Sanger sequencing, multiplex ligation-dependent probe amplification (MLPA), and long-range polymerase chain reaction (PCR) were performed to comprehensively study BRCA1/2. The genetic risk models BRCAPRO, Myriad, and BOADICEA were used to evaluate the mutation analysis. Results In total, 131 patients were enrolled. Of the 131 patients, Sanger sequencing identified 16 different BRCA1/2 small-scale mutations in 20 patients (15.3%). Two novel nonsense mutations were detected in 2 patients with a serous borderline tumor and a large-cell neuroendocrine carcinoma. MLPA analysis of BRCA1/2 in Sanger-negative patients revealed 2 LGRs. The LGRs accounted for 14.3% of all identified BRCA1 mutations, and the prevalence of LGRs identified in this study was 1.8% in 111 Sanger-negative patients. The genetic risk models showed statistically significant differences between mutation carriers and non-carriers. The 2 patients with LGRs had at least one blood relative with breast or ovarian cancer. Conclusion Twenty-two (16.8%) of the unselected ovarian cancer patients had BRCA1/2 mutations that were detected through comprehensive BRCA1/2 genetic testing. Ovarian cancer patients with Sanger-negative results should be considered for LGR detection if they have one blood relative with breast or ovarian cancer. The detection of more BRCA1/2 mutations in patients is important for efforts to provide targeted therapy to ovarian cancer patients.

Dear Editor Mycobacterium parascrofulaceum is a member of slow-growing scotochromogenic nontuberculous mycobacteria (NTM) that can cause opportunistic infections in immunocompromised patients [1]. Only a few clinical infections with this strain have been reported to date [1, 2, 3, 4]. We describe a case of M. parascrofulaceum pulmonary infection in a patient with bronchiectasis. To our knowledge, this is the first case of M. parascrofulaceum infection in Korea. A 65-yr-old man was referred to our hospital because of recurrent hemoptysis and prulent sputum for two days. He had a history of stomach cancer that had been treated by using total gastrectomy with Billroth II anastomosis and chemotherapy seven years ago; at that time, he was diagnosed as having bronchiectasis. Our laboratory tests revealed peripheral blood leukocyte counts of 6.48×109/L with 81.2% neutrophils. Chest computed tomography revealed no interval changes in the preexisting bronchiectasis of the lower left lobe of the lung. Nonetheless, new peribronchial infiltration and centrilobular nodules were found in the middle right lobe and lower left lobe. Acid-fast bacillus (AFB) staining, qualitative real-time PCR for Mycobacterium tuberculosis (COBAS TaqMan MTB Test; Roche, Basel, Switzerland), and nested PCR for NTM (MTB & NTM PCR Kit; BioSewoom Inc., Seoul, Korea) in the expectorated-sputum specimens all tested negative. Sputum cultures in liquid media were performed in triplicate by using the Mycobacteria Growth Indicator Tube System (MGIT, Becton, Dickinson and Company, Franklin Lakes, NJ, USA), and positive results were obtained from two cultures. For species identification, a PCR-based reverse line blot hybridization assay for the ITS gene (AdvanSure Mycobacteria GenoBlot Assay; LG Life Sciences, Seoul, Korea) was performed on both culture isolates, revealing poor discrimination of species (Mycobacterium lentiflavum/Mycobacterium genavense). For definitive species identification, sequencing analysis of the 16S rRNA, hsp65, and rpoB genes was performed. Primers used for PCR are shown in Table 1 [5, 6, 7]. 16S rRNA sequences obtained were searched against publicly available databases by using the basic local alignment search tool (BLAST) [8] and EzTaxon [9]. When the sequences were submitted to BLAST, both culture isolates revealed 99.74% similarity (767/769 bp) with M. parascrofulaceum HSC68. The next closest match was M. parascrofulaceum ATCC BAA-614 with similarity of 99.61% (776/779 bp). In EzTaxon, the isolates exhibited 99.36% similarity (773/778 bp) with M. parascrofulaceum ATCC BAA-614 followed by M. europaeum FI-95228 with similarity of 98.94% (750/758 bp). In the BLAST search, sequences of hsp65 and rpoB genes revealed 99.83% (602/603 bp) and 99.32% (740/745 bp) similarity with M. parascrofulaceum, respectively. The other best matches were Mycobacterium sp. MOTT-01 (99.83%, 602/603 bp) and Mycobacterium sp. MOTT-27 (99.06%, 739/746 bp), respectively. A phylogenetic tree, which was constructed using the neighbor-joining method by means of the MEGA software, version 5.05 (http://www.megasoftware.net), identified this isolate as M. parascrofulaceum (Fig. 1). Although there was a possibility of colonization of the respiratory tract, the patient was diagnosed as having M. parascrofulaceum pulmonary infection according to his newly developed radiological images. At diagnosis, he had only a mild cough with no progression according to chest radiography. Therefore, he did not receive long-term antibiotic therapy. Additional sputum cultures one year after the initial sputum analysis yielded negative results. Currently, he exhibits no symptomatic aggravation and regularly visits our hospital (and does not take medication). Therefore, it is possible that this isolate, M. parascrofulaceum, caused a transient infection rather than a progressive disease or colonization. We need long-term follow-up and repeat sputum analysis to confirm either the progressive disease or transient infection. Fig. 1 The neighbor-joining phylogenetic tree based on the 16S rRNA gene sequences of our Mycobacterium parascrofulaceum isolate and 19 similar microorganisms. The scale bar corresponds to 0.2% sequence divergence. Table 1 Primers and amplicon sizes for PCR analysis of the 16s rRNA, hsp65, and rpoB genes There are >150 species comprising the genus Mycobacterium, with a significant increase in the number of newly identified species recently. The latter phenomenon can be attributed in part to development of molecular techniques enabling accurate identification via detection of differences in the 16S rRNA gene [10]. M. parascrofulaceum is one of the species discovered recently after sequence-based identification and was previously known as the "MCRO 33" group of mycobacteria (GenBank accession No. {"type":"entrez-nucleotide","attrs":{"text":"AF152559","term_id":"5353729","term_text":"AF152559"}}AF152559). Discrimination of M. parascrofulaceum from other NTM is difficult because it shows phenotypic characteristics similar to those of Mycobacterium scrofulaceum and is genotypically close to Mycobacterium simiae [1]. Direct 16S rRNA gene sequence analysis is a powerful tool for confirming this strain; additional sequence analysis of the hsp65, rpoB, and ITS genes may be useful for unequivocal identification [10]. As the genetic diversity of NTM continues to be elucidated and new species are discovered, more accurate and specific diagnostic tests will be necessary for NTM identification. Multigene sequence analysis may be needed to discriminate NTM species accurately.

Phialemonium keratitis is a very rare case and we encountered a case of keratitis caused by Phialemonium obovatum (P. obovatum) after penetrating injury to the cornea. This is the first case report in the existing literature. A 54-year-old male was referred to us after a penetration injury, and prompt primary closure was performed. Two weeks after surgery, an epithelial defect and stromal melting were observed near the laceration site. P. obovatum was identified, and then identified again on repeated cultures. Subsequently, Natacin was administered every two hours. Amniotic membrane transplantation was performed due to a persistent epithelial defect and impending corneal perforation. Three weeks after amniotic membrane transplantation, the epithelial defect had completely healed, but the cornea had turned opaque. Six months after amniotic membrane transplantation, visual acuity was light perception only, and corneal thinning and diffuse corneal opacification remained opaque. Six months after amniotic membrane transplantation, visual acuity was light perception only, and corneal thinning and diffuse corneal opacification remained.

Background: Optimal blood culture performance is critical for successful diagnosis and treatment of sepsis. To understand the sta- tus of blood culture, we investigated several aspects of the procedure at 9 university hospitals. Methods: The process of ordering blood culture sets and sampling volume for adults and children was investigated from January 2010 to April 2010, while the positive rate of detection and growth of skin contaminants were compared in 2009. Microbial growth in aerobic and anaerobic bottles was investigated prospectively. Results: A majority of the hospitals used 2 sets of bottles for adults and 1 bottle for children. The average blood volume in each set was 7.7 mL for adults and 2.1 mL for children. The positive rate of microorganisms was 8.0%, and the isolation rate of the normal flora of the skin was 2.1%. Bacterial growth rates in aerobic and anaerobic bottles only were 31.8% and 24.5% respectively. Conclusions: Ordering blood culture sets and sampling volumes did not comply with CLSI guidelines. However, the rate of positive cultures and skin contamination rates were acceptable. Anaerobic bottles are useful in enhancing the yield of microorganisms.

Background : With the emergence of antimicrobial resistance among Streptococcus pneumoniae, a more accurate and automated antimicrobial susceptibility testing method is essential. We evaluated the BD Phoenix Automated Microbiology System (Becton Dickinson Diagnostic Systems, USA) SMIC/ID-2 panel for antimicrobial susceptibility testing of S. pneumoniae. Methods : A total of 113 clinical strains of S. pneumoniae (88 penicillin susceptible strains, 8 intermediate strains, and 17 resistant strains by 2008 CLSI criteria) were tested. Minimum inhibitory concentrations (MICs) for penicillin, cefotaxime, clindamycin, erythromycin, levofloxacin, trimethoprim/ sulfamethoxazole, tetracycline, and vancomycin were determined by Etest (AB Biodisk, Sweden) and Phoenix System. The results obtained by Phoenix system were compared to those obtained by Etest. Results : The overall essential agreement of MICs (within one dilution of MICs) defined by the Phoenix and Etest was 92.3%. Neither very major errors nor major errors were produced, and minor errors were 6.5%. Minor errors were frequently observed in susceptibility testings for penicillin (22.1%), cefotaxime (12.4%), and trimethoprim/sulfamethoxazole (11.5%). Conclusions : The Phoenix SMIC/ID-2 panel provided a simple and rapid susceptibility testing for S. pneumoniae, and the results were in a good agreement with those of Etest. The Phoenix system appears to be an effective automated system in clinical microbiology laboratories.

Loss-of-function mutations in the putative tumor suppressor gene, Ten-Eleven Ttranslocation 2(TET2), have been identified recently in myeloproliferative neoplasms (MPNs). The present study analyzed the TET2 gene in 99 MPNs patients. The overall TET2 mutational frequency was 12.1% (22.2% in polycythemia vera (PV), 9.7% in essential thrombocythemia (ET), 18.2% in primary myelofibrosis (PMF,) and 0% in unclassified MPNs), and 11 mutations (p.Lys95Asnfs*18, p.Gln967Asnfs*40, p.Lys1022Glufs*4, p.Asp1314Metfs*49, p.Gln1534Alafs*43, p.Tyr1618Leufs*4, p.Leu1609Glufs*45, p.Gly1735*, Q599R, c.3409+1GT, c.4044+2insT) were identified. All the patients with TET2 mutation were accompanied by the JAK2 V617F mutation. The existence of the TET2 mutation was not related to the patient's age, hematologic indices, JAK2 V617F allele burden, frequencies of organomegaly, marrow fibrosis, or thrombotic/hemorrhagic complications in entire MPN patients. However, tendencies toward higher JAK2 V617F allele burdens (88.0±4.3% vs. 19.1±28.7%, P=0.034) and higher Hct (47.4±5.4% vs. 25.5±6.2%, P=0.037) were detected in PMF patients harboring TET2 mutations. Moreover, a significantly higher frequency of organomegaly was identified in ET patients harboring the TET2 mutation (50% vs. 19.6%, P=0.018). The TET2 mutation most likely contributes to clinical phenotypes and shows a high accompanying rate with JAK2 V617F; larger scale studies involving more MPN patients are needed.

Pseudomonas aeruginosa isolates containing the bla IMP-6 gene were recovered from 5 patients hospitalized at a tertiary-care hospital in Korea. The bla IMP-6 gene was in a class 1 integron containing 5 different insert gene cassettes. All of the isolates showed identical pattern in Spe I macrorestriction analysis.

The aims of the current study were to investigate the prevalence and molecular characteristics of plasmid-mediated quinolone resistance (PMQR) genes from colonizing fecal organisms and to compare the incidence and subtype of these genes according to bacterial species and hospital at five tertiary-care hospitals in Korea. A total of 500 nonduplicated clinical isolates of Enterobacteriaceae were obtained from fecal specimens at five tertiary-care hospitals between March and May 2008. The PMQR genes (qnrA, qnrB, qnrS, aac(6')-Ib-cr, and qepA) were amplified by PCR and confirmed by direct sequencing of the PCR products. A total of 83 (16.6%) qnr-positive isolates were detected. The prevalence rates of qnrA, qnrB, and qnrS were 1.4%, 13.6%, and 1.6%, respectively. The species distributions of qnrB-positive isolates were Klebsiella pneumoniae (37/109; 33.9%), Citrobacter freundii (10/34; 29.4%), Citrobacter braakii (8/13; 61.5%), and Escherichia coli (8/275; 2.9%). Sixteen subtypes of qnrB were detected, including seven novel variants. The prevalences of aac(6')-Ib-cr and qepA were 15.6% (n=78) and 0.6% (n=3), respectively. The aac(6')-Ib-cr gene was detected in 39 (47.0%) of 83 qnr-positive isolates and 39 (9.4%) of 417 qnr-negative isolates There was one qepA variant containing a novel mutation (Ala231Val). The prevalence of PMQR genes was high in Enterobacteriaceae from stool specimens in Korea, and there was a close relation between qnr and aac(6')-Ib-cr.

Accurate and early detection of vancomycin-resistant enterococci (VRE) is critical for controlling nosocomial infection. In this study, we evaluated the usefulness of a selective chromogenic agar medium and of multiplex PCR for detection of VRE, and both these techniques were compared with the conventional culture method for VRE detection.We performed the following 3 methods for detecting VRE infection in stool specimens: the routine culture method, culturing in selective chromogenic agar medium (chromID VRE, bioMérieux, France), and multiplex PCR using the Seeplex® VRE ACE Detection kit (Seegene Inc., Korea) with additional PCR for vanC genes.We isolated 109 VRE strains from 100 stool specimens by the routine culture method. In chromID VRE, all the isolates showed purple colonies, including Enterococcus gallinarum and E. raffinosus, which were later identified using the Vitek card. All VRE isolates were identified by the multiplex PCR method; 100 were vanA-positive E. faecium, 8 were vanA- and vanC-1-positive E. gallinarum, and 1 was vanA-positive E. raffinosus.For VRE surveillance, culturing the isolates in chromID VRE after broth enrichment appears to be an accurate, rapid, and easy method for routine screening test. Multiplex PCR is relatively expensive and needs skilled techniques for detecting VRE, but it can be an auxiliary tool for rapid detection of genotype during a VRE outbreak.

The Beijing family of Mycobacterium tuberculosis has been emerging in the world. However, there are few nationwide data of genotypic distribution in Korea. This study aimed to identify the genotypic diversity of clinical isolates of M. tuberculosis and to demonstrate the population of Beijing family in Korea. We collected 96 clinical M. tuberculosis isolates from 11 university hospitals nationwide in Korea from 2008 to 2009. We observed 24 clusters in IS6110-RFLP analysis and 19 patterns in spoligotyping. Seventy-five isolates were confirmed to be Beijing family. Two isolates of the K strain and 12 isolates of the K family strain were also found. We found that drug resistance phenotypes were more strongly associated with Beijing family than non-Beijing family (P=0.003). This study gives an overview of the distribution of genotypes of M. tuberculosis in Korea. These findings indicate that we have to pay more attention to control of M. tuberculosis strains associated with the Beijing family.

In the present day, pretransfusion tests include ABO and RhD grouping, antibody screening, antibody identification, and cross matching. Although error rates for these tests have decreased compared to those in the past, clerical errors still occur. When exposed to RhD positive RBCs, a RhD negative person can produce anti-D that causes a severe hemolytic disease of the fetus and the newborn in addition to hemolytic transfusion reactions. Therefore, administration of RhD positive RBCs to a RhD negative person should be avoided. We experienced a RhD negative patient who had been misidentified as positive and transfused 35 units of RhD positive RBCs eight years ago, but did not have detectable anti-D in present. The red cells of the patient showed no agglutination with the anti-D reagent and a negative result in the standard weak D test. The multiplex PCR with sequence-specific priming revealed that the patient was RhD negative.

Purpose: To report a case of Phoma glomerata keratitis occurring in recurrent herpes simplex keratitis cicatrix. Case summary: A 63-year-old male patient was admitted to our hospital with complaints of abrupt visual deterioration and ocular pain in his left eye. He was treated for recurrent herpes simplex keratitis in the same eye 12 years prior. Because central desmatocele was observed as a result of advanced corneal stromal melting, Gram staining, Potassium Hydroxide (KOH) mount, and culture were performed in corneal scrape specimens. On microbiological evaluation, a Phoma species was detected and Phoma glomerata was diagnosed using DNA sequencing method. Two consecutive amniotic membrane transplantations were performed with topical antifungal agents. The lesion was not improved when using topical amphotericin B and natamycin eyedrops, thus fluconazole eyedrops were used additionally. The corneal infection was resolved with central thick opacification. Conclusions: In the present case, herpetic keratitis was the main underlying causative factor because the patient had no past history of trauma. When diverse appearances of keratitis occur in herpes simplex keratitis patients, clinicians need to consider the concurrence of fungal infection, especially Phoma glomerata, a rare fungal organism. J Korean Ophthalmol Soc 2014;55(8):1229-1232

Abstract 1455 Background: Since the acquired somatic mutation, JAK2 V617F, was discovered as a first molecular marker of myeloproliferative neoplasms (MPN), and it has been detected variably in each MPN subtypes. However, JAK2 V617F does not found in all of MPN cases and not necessarily specific to a particular clinicpathologic entity. Recently, mutation of the putative tumor suppressor gene, Ten-Eleven-Translocation-2(TET2), has been identified in MPN patients. However, the frequency of TET2 mutation or its relationship with JAK2 V617F mutation or pathologic function in MPN has not been concluded, yet. The aim of our study was to evaluate the frequency of TET2 in MPN patients, and whether there is any correlation of TET2 mutation with JAK2V617F mutation or the clinicohematologic parameters. Materials and Methods: Total 99 adult MPN patients (18 PV, 62 ET, 11 PMF and 8 MPN unclassified) whose bone marrow cells had been stored from 2007 to 2010 at point of first diagnosis were included in this study. Hematological diagnoses and subtyping were reconfirmed according to the 2008 WHO classification and clinicohematologic datas were collected from patient records. Direct sequencing for TET2(exon3–11) and JAK2 (exons 12 and 14) were performed using an ABI 3730XL DNA analyzer. The JAK2V617F allele burdens were determined by pyrosequencing for samples available and MPL was analyzed by allele-specific PCR. Results: The overall TET2 mutational frequency was 12.1%, and disease-specific mutational frequencies were 22.2% in PV, 9.7% in ET and 18.2% in PMF. The found mutations included 11 mutations, 7 frame-shift (p.Lys95AsnfsX18, p.Gln967AsnfsX40, p.Lys1022GlufsX4, p.Asp1314MetfsX49, p.Gln1534AlafsX43, p.Tyr1618LeufsX4, p.Leu1609GlufsX45), 1 nonsense (p.Gly1735X), 1 missense (Q599R) and 2 splicing mutations (c.3409+1G>T, c.4044+2insT). Those mutations most frequently involved exon 3(four mutations) and exon 11(four mutaions), and rarely intron 3, intron 8 and exon 7. None of the mutations were associated with a karyotypically apparent 4q24 rearrangement. All patients were also screened for JAK2 V617F, and the overall JAK2 V617F positive rate was 68%(94.4% in PV, 69.4% in ET, 45.5% in PMF and 37.5% in MPN, unclassified). All TET2 mutations occurred in JAK2 V617F positive cases. JAK2 exon12 mutation was not found in all patients. MPL W515L was found in one ET patient who also carried JAK2V617F, but not TET2 mutation. Information on JAK2 V617F allele burden was available in 78 patients. Considering all 99 patients, the patient age, hematologic indexes (leukocyte count, neutrophil fraction, lymphocyte fraction, monocyte fraction, Hb, Hct and platelet count), the frequency of organomegaly, marrow fibrosis or thrombotic/hemorrhagic complications were not different according to carrying TET2 mutation. However, TET2 mutation was more frequently found in JAK2 V617F carriers than non-carriers (P=0.008), but JAK2 V617F allele burden did not correlated with the presence of mutant TET2. When analysis was performed for each PV, ET, and PMF (no TET2 mutation in MPN-unclassifiable patients), correlation between TET2 and JAK2 V617F mutational status was not found in each subtypes (P=0.078 in PV, P=0.099 in ET and P=0.182 in PMF). However, the JAK2 V617F allele burden was significantly higher in PMF harboring TET2 mutation than PMF patients did not (88.0 ± 4.3% vs 19.1 ± 28.7%, P=0.034). In statistical analysis for the correlations of clinicohematologic parameters with TET2 mutation in each PV, ET and PMF patients, only a few statistically significant results were identified. The presence of TET2 mutation was correlated with high Hct in PMF (47.4 ± 5.4 vs 25.5 ± 6.2, P=0.037), and TET2 positive ET patients showed relatively higher frequency of organomegaly compared to ET patients without TET2 mutation (50% vs 19.6%, P=0.018). Conclusions: The overall and disease-specific frequencies of TET2 mutation in our study are similar with previous studies, and frame-shift mutation is the most frequent mutation type. There is no specific relationship between JAK2 V617F and TET2 mutation occurrence, but TET2 mutant PMF has higher JAK2 V617F allele burden than non-mutant. TET2 mutation is also associated with a higher Hct in PMF and higher frequency of organomegaly in ET. Larger scale studies involving more MPN patients are needed. Disclosures: No relevant conflicts of interest to declare.

Number of Blood Cultures per 1,000 Patient Days at University-Affiliated Hospitals in Korea Eui Chong Kim, Jeong Hwan Shin, Sunjoo Kim, Nam Yong Lee, Ji-Hyun Cho, Sun Hoe Koo, Nam Hee Ryoo, Sae Ick Joo Departments of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Inje University College of Medicine, Busan, Gyeongsang National University School of Medicine, Jinju, Sungkyunkwan University School of Medicine, Samsung Medical Center, Seoul, Wonkwang University Medical School, Iksan, Chungnam National University College of Medicine, Daejeon, Keimyung University School of Medicine, Daegu, Korea

Background: Metallo-β-lactamases (MBLs) have been reported in gram negative bacilli and are becoming increasingly important clinically because the enzymes hydrolyse almost all β-lactams, including carbapenems. Thus, the present study was conducted to determine the prevalence of MBL types in imipenem-nonsusceptible Pseudomonas aeruginosa and Acinetobacter baumannii isolated from a tertiary teaching hospital. Methods: Imipenem-nonsusceptible strains, 128 P. aeruginosa and 93 A. baumannii, were collected from clinical specimens. Identification and susceptibility tests were determined by Vitek GNI and GNS cards. MBL production was determined by modified Hodge test and imipenem-EDTA synergy test. Multiplex PCR amplification of MBL genes including blaIMP-1, blaVIM-1 and blaVIM-2 were performed. Results: Thirty-one P. aeruginosa (24.2%) isolates and 3 A. baumannii (3.2%) were found to be MBL producers. In P. aeruginosa, 20 (15.6%) and 11 (8.6%) isolates were positive for blaIMP-1 and blaVIM-2, respectively whereas 1 (1.0%) and 2 (2.2%) isolates in A. baumannii, respectively. Conclusion: IMP-1 is more prevalent MBL type than VIM-2 among imipenem-nonsusceptible P. aeruginosa unlike in other studies. Larger numbers of isolates and sequential studies are strongly recommended for the useful evaluation and monitoring of MBL production in the hospital setting to infection-control. (Korean J Clin Microbiol 2010;13:169-172)

A 13-year-old girl presented in a local clinic with intermittent left ankle pain for 3 months without any history of trauma. She often had discomfort in walking but with no altered sensation or swelling. The patient was transferred to our hospital for the persistent pain in her left ankle. Fever and other constitutional symptoms were absent at presentation. There was no family history of specific illness and no evidence of any underlying diseases. A physical examination revealed swelling and mild tenderness of her left ankle. She had no systolic murmur or other specific findings. She undertook simple radiography and magnetic resonance imaging (MRI). Preoperatively, blood examination revealed a leukocyte count of 6.0×10/L (reference range, 4.0∼10.0×10/L) with neutrophils in 54%, a hemoglobin level of 12.5 g/dL (reference range, 12∼14 g/dL) and a platelet count of 398×10/L (reference range, 140∼ 450×10/L). C-reactive protein level was at 0.08 mg/dL (reference range, 0∼0.5 mg/dL), and an erythrocyte sedimentation rate at 6 mm/hr (reference range

We experienced a case in which yeasts in blood sample from a patient with cervical cancer with hepatic metastasis and multiple intraperitoneal cysts interfered with platelet morphology flag in automated blood analyzer. The peripheral blood smear was performed to confirm the flag and revealed intracellular and extracellular yeasts, which were subsequently identified as Candida parapsilosis by blood culture. (Korean J Clin Microbiol 2009;12:138-140)

Children with Down syndrome (DS) have a higher risk of developing leukemia than do healthy children, and they especially have a higher risk for developing transient myeloproliferative disorder (TMD) or acute megakaryocytic leukemia (AMKL). In recent studies, it has been reported that most of these patients have acquired mutation of the GATA1 gene, which encodes the erythroid/megakaryocytic transcription factor GATA1. GATA1 mutations have not been found in AMKL patients who did not have DS and other hematologic malignancies in DS. Most of the GATA1 mutations in DS-TMD/AMKL are nonsense mutations that are mainly located in exon 2. We observed a nonsense mutation in exon 2 of GATA1 [c.189_190delCA (Tyr63X)] in one case of DS-TMD. The GATA1 mutation has been thought to be an early event in the leukemogenesis of DS-TMD/AMKL and it could be used as a stable molecular marker to assess the treatment response or to monitor for the recurrence of DS-TMD/AMKL.

Interleukin (IL)-12 activates T helper (Th) 1 cells to produce interferon (IFN)-gamma which inhibits atopic inflammation. IL-12 acts through interaction with its receptor, especially beta(2) subunit. In several studies, the low production of IFN-gamma in peripheral mononuclear cells of atopic patients on response to IL-12 stimulation has been reported. Therefore we investigated the IL-12 receptor beta(2) (IL-12R beta(2)) mRNA expression and RNA editing, nucleotide 2451 C-to-U conversion, to find the cause of low responsiveness to IL-12 in atopy. Quantitative real time PCR for mRNA expression and sequence analysis for RNA editing were performed in 80 atopic patients and 54 healthy controls. The expression of IL-12R beta(2) mRNA was significantly lower in atopic patients than healthy controls (p0.05). In sequence analysis, RNA editing on nucleotide 2451 was not found from either atopic patients or healthy controls. In additional evaluation, there was no relationship between expression of IL-12R beta(2) mRNA and serum total IgE or blood eosinophil count. Reduced IL-12R beta(2) mRNA expression in atopic patients indicate the reduced capacity to respond to IL-12 which induce IFN-gamma production and this may contribute to Th2-skewed immune response in atopy.

Purpose:Bacteremia is one of the major concerns in the treatment of pediatric cancer patients. This study was to determine the etiologic agents and the pattern of antibiotic susceptibilities in a single tertiary medical center. Methods:We retrospectively reviewed the medical records of the cases of bacteremia in pediatric cancer patients from 1998 to 2005 in Keimyung University Dongsan Medical Center. Results:There were 62 cases of bacteremia from 44 patients. Gram-positive organisms(48.3%) were more common than gram-negative organisms(38.7%) or fungi(13%). Among gram-positive organisms, Staphylococcus epidermidis was the most common etiologic agent(63.3%), followed by Staphylococcus aureus(16.7%), α-hemolytic Streptococcus(16.7%), and Streptococcus mitis(3.3%). Among gram-negative organisms, Alcaligenes xylosoxidans was the most common agent(41.7%) and the other organisms were Klebsiella pneumoniae(20.8%), Stenotrophomonas maltophilia(12.5%), Acinetobacter baumanii(8.2%), etc. In febrile neutropenic patients, however, K. pneumoniae was the most common cause of gram-negative bacteremia. All of the isolated K. pneumoniae in our center produced extended-spectrum beta-lactamase and were related with high mortality. S. aureus, S. epidermidis, and Streptococcus species were all susceptible to vancomycin and teicoplanin. Most staphylococci were resistant to penicillin and oxacillin. Most of the gram-negative organisms were susceptible to imipenem. Conclusion:Gram-positive organisms were more commonly isolated than gram-negative organisms in pediatric cancer patients like other studies. We could obtained valuable information on the choice of proper antibiotics in our institution. Further studies will be needed to explain the prevalence of A. xylosoxidans in our center