Nam-Joong Kim

Outcome of Vancomycin Treatment in Patients with Methicillin-Susceptible Staphylococcus aureus Bacteremia

ABSTRACT Limited data on the clinical outcome of vancomycin treatment compared with that of beta-lactam treatment in patients with methicillin-susceptible Staphylococcus aureus bacteremia (MSSA-B) are available. We used different and complementary approaches: (i) a retrospective cohort study using a propensity score to adjust for confounding by treatment assignment and (ii) a matched case-control study. Of all patients with S. aureus bacteremia (SAB) in two university-affiliated hospitals over a 7-year period, 294 patients with MSSA-B were enrolled in the cohort study. The cases for the case-control study were defined as patients who received vancomycin treatment for MSSA-B; the controls, who were patients that received beta-lactam treatment for MSSA-B, were selected at a 1:2 (case:control) ratio according to the objective matching scoring system and the propensity score system. In the cohort study, SAB-related mortality in patients with vancomycin treatment (37%, 10/27) was significantly higher than that in those with beta-lactam treatment (18%, 47/267) (P = 0.02). In addition, multivariate analysis revealed that vancomycin treatment was associated with SAB-related mortality when independent predictors for SAB-related mortality and propensity score were considered (adjusted odds ratio of 3.3, 95% confidence interval of 1.2 to 9.5). In the case-control study using the objective matching scoring system and the propensity score system, SAB-related mortality in case patients was 37% (10/27) and in control patients 11% (6/54) (P < 0.01). Our data suggest that vancomycin is inferior to beta-lactam in the treatment of MSSA-B.

Severe fever with thrombocytopenia syndrome, South Korea, 2012.

We report a retrospectively identified fatal case of severe fever with thrombocytopenia syndrome (SFTS) in South Korea from 2012. SFTS virus was isolated from the stored blood of the patient. Phylogenetic analysis revealed this isolate was closely related to SFTS virus strains from China and Japan.

Diagnostic usefulness of a T-cell-based assay for extrapulmonary tuberculosis in immunocompromised patients

BACKGROUND The low reactivity of the tuberculin skin test limits its clinical use in immunocompromised patients with extrapulmonary tuberculosis. A recently developed T-cell-based assay for diagnosing tuberculosis infection gave promising results. However, there were few data on the usefulness of this assay for diagnosing extrapulmonary tuberculosis in immunocompromised patients. METHODS All adult patients with suspected extrapulmonary tuberculosis were prospectively enrolled at 2 university-affiliated hospitals over an 18-month period. In addition to the conventional tests for diagnosing extrapulmonary tuberculosis, enzyme-linked immunospot (ELISPOT) assay for the interferon-gamma-producing T-cell response to early secretory antigenic target-6 and culture filtrate protein-10 was performed. The final diagnoses in patients with suspected extrapulmonary tuberculosis were classified by clinical category. RESULTS There were 179 patients with suspected extrapulmonary tuberculosis enrolled: 59 (33%) were classified as immunocompromised. Of the 179 patients, 75 (42%) were classified as extrapulmonary tuberculosis, including 56 confirmed tuberculosis plus 19 probable tuberculosis, and 97 (54%) were classified as not tuberculosis. The remaining 7 (4%) had possible tuberculosis and were excluded from the final analysis. The tuberculin skin test (induration size >or=10 mm) was less sensitive in immunocompromised patients (38%; 95% confidence interval [CI], 19%-59%) than in immunocompetent patients (69%; 95% CI, 54%-81%, P=.01). In contrast, the ELISPOT assay retained a high sensitivity: (88%; 95% CI, 68%-97%) in immunocompromised patients compared with 96% (95% CI, 87%-100%) in immunocompetent patients (P=.32). CONCLUSION The immunosuppressive condition does not affect the diagnostic sensitivity of the ELISPOT assay for extrapulmonary tuberculosis.

Diagnosis of central nervous system tuberculosis by T-cell-based assays on peripheral blood and cerebrospinal fluid mononuclear cells.

ABSTRACT In active tuberculosis (TB), Mycobacterium tuberculosis-specific T cells are compartmentalized more to the site of infection than to the circulating blood. Therefore, an M. tuberculosis-specific enzyme-linked immunospot (ELISPOT) assay with samples from the site of infection may permit a more sensitive or specific diagnosis of active central nervous system (CNS) TB than that achieved by the assay with blood alone. Therefore, we prospectively evaluated the usefulness of circulating and compartmentalized mononuclear cell (MC; i.e., peripheral blood mononuclear cell [PBMC] and cerebrospinal fluid [CSF] MC)-based ELISPOT assays (i.e., the T-SPOT.TB test) for the diagnosis of active TB in patients with suspected CNS TB. The clinical categories of CNS TB were classified as described previously (G. E. Thwaites, T. T. Chau, K. Stepniewska, N. H. Phu, L. V. Chuong, D. X. Sinh, N. J. White, C. M. Parry, and J. J. Farrar, Lancet 360:1287-1292, 2002). Thirty-seven patients with suspected CNS TB were enrolled over a 12-month period. Of these, 31 (84%) showed clinical manifestations of suspected TB meningitis and 6 (16%) gave indications of intracranial tuberculoma with disseminated TB. The final clinical categories of the 37 patients with suspected CNS TB were as follows: 12 (32%) were classified as having CNS TB (7 with confirmed TB, 3 with probable TB, and 2 with possible TB) and 25 (68%) were classified as not having active TB. The sensitivity and specificity of the PBMC ELISPOT assay were 91% (95% confidence interval [CI], 59% to 100%) and 63% (95% CI, 41% to 81%), respectively. By comparison, the sensitivity and specificity of the CSF MC ELISPOT assay were 75% (95% CI, 19% to 99%) and 75% (95% CI, 43% to 95%), respectively. When the ratio of the CSF MC ELISPOT assay results to the PBMC ELISPOT results was 2 or more, the sensitivity and specificity were 50% (95% CI, 7% to 93%) and 100% (95% CI, 74% to 100%), respectively. The ELISPOT assay with PBMCs and CSF MCs is a useful adjunct to the current tests for the diagnosis of CNS TB.

Effect of Routine Sterile Gloving on Contamination Rates in Blood Culture: A Cluster Randomized Trial

BACKGROUND Blood culture contamination leads to inappropriate or unnecessary antibiotic use. However, practical guidelines are inconsistent about the routine use of sterile gloving in collection of blood for culture. OBJECTIVE To determine whether the routine use of sterile gloving before venipuncture reduces blood culture contamination rates. DESIGN Cluster randomized, assessor-blinded, crossover trial (ClinicalTrials.gov registration number: NCT00973063). SETTING Single-center trial involving medical wards and the intensive care unit. PARTICIPANTS 64 interns in charge of collection of blood for culture were randomly assigned to routine-to-optional or optional-to-routine sterile gloving groups for 1854 adult patients who needed blood cultures. INTERVENTION During routine sterile gloving, the interns wore sterile gloves every time before venipuncture, but during optional sterile gloving, sterile gloves were worn only if needed. MEASUREMENTS Isolates from single positive blood cultures were classified as likely contaminant, possible contaminant, or true pathogen. Contamination rates were compared by using generalized mixed models. RESULTS A total of 10 520 blood cultures were analyzed: 5265 from the routine sterile gloving period and 5255 from the optional sterile gloving period. When possible contaminants were included, the contamination rate was 0.6% in routine sterile gloving and 1.1% in optional sterile gloving (adjusted odds ratio, 0.57 [95% CI, 0.37 to 0.87]; P = 0.009). When only likely contaminants were included, the contamination rate was 0.5% in routine sterile gloving and 0.9% in optional sterile gloving (adjusted odds ratio, 0.51 [CI, 0.31 to 0.83]; P = 0.007). LIMITATION Blood cultures from the emergency department, surgical wards, and pediatric wards were not assessed. CONCLUSION Routine sterile gloving before venipuncture may reduce blood culture contamination.

Clinical Responses to Smallpox Vaccine in Vaccinia-Naive and Previously Vaccinated Populations: Undiluted and Diluted Lancy-Vaxina Vaccine in a Single-Blind, Randomized, Prospective Trial

We conducted a single-blind, randomized trial of 2 dilutions (1:1 or 1:10) of Lancy-Vaxina vaccine (Berna Biotech) in vaccinia-naive persons (n=36) and persons previously vaccinated >25 years ago (n=76). All vaccinees responded successfully to the vaccination. There were no significant differences in the size of the skin lesions, the number of adverse events, the amount of viral shedding, or the level of antibody responses between the undiluted (n=56) and diluted (n = 56) vaccine groups. Compared with vaccinia-naive persons, previously vaccinated persons exhibited significantly smaller and more rapidly evolving skin lesions and fewer adverse events. Previously vaccinated persons had significantly higher neutralizing antibody levels before the administration of the study vaccine than vaccinia-naive persons, and viral shedding from lesions in previously vaccinated persons was lower and diminished more rapidly than from lesions in vaccinia-naive persons.

Human Granulocytic Anaplasmosis, South Korea, 2013

We report a patient with human granulocytic anaplasmosis in South Korea. The patient had fever and thrombocytopenia. Human granulocytic anaplasmosis was confirmed by seroconversion, PCR, and sequence analysis for Anaplasma phagocytophilum. Morulae were observed in the cultured HL-60 cells inoculated with blood from the patient.

Clinical and Epidemiological Factors Associated with Methicillin Resistance in Community-Onset Invasive Staphylococcus aureus Infections: Prospective Multicenter Cross-Sectional Study in Korea

Successful empirical therapy of Staphylococcus aureus infections requires the ability to predict methicillin resistance. Our aim was to identify predictors of methicillin resistance in community-onset (CO) invasive S. aureus infections. Sixteen hospitals across Korea participated in this study from May to December 2012. We prospectively included cases of S. aureus infection in which S. aureus was isolated from sterile clinical specimens ≤72 hours after hospitalization. Clinical and epidemiological data were gathered and compared in methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) cases. Community-associated (CA) infections were defined as in previous studies. In total, there were 786 cases of community-onset S. aureus infection, 102 (13.0%) of which were CA-MRSA. In addition to known risk factors, exposure to 3rd generation cephalosporins in the past 6 months [odds ratio (OR), 1.922; 95% confidence interval (CI), 1.176–3.142] and close contact with chronically ill patients in the past month (OR, 2.647; 95% CI, 1.189–5.891) were independent risk factors for MRSA infection. However, no clinical predictors of CA-MRSA were identified. Methicillin resistance, CO infection, and appropriateness of empirical antibiotics were not significantly related to 30-day mortality. MRSA infection should be suspected in patients recently exposed to 3rd generation cephalosporins or chronically-ill patients. There were no reliable predictors of CA-MRSA infection, and mortality was not affected by methicillin resistance.

The burden of nosocomial staphylococcus aureus bloodstream infection in South Korea: a prospective hospital-based nationwide study

BackgroundWe estimated the nationwide burden of nosocomial S. aureus bloodstream infection (SA-BSI), a major cause of nosocomial infection, in South Korea.MethodsTo evaluate the nationwide incidence of nosocomial SA-BSI, cases of SA-BSI were prospectively collected from 22 hospitals with over 500 beds over 4?months. Data on patient-days were obtained from a national health insurance database containing the claims data for all healthcare facilities in South Korea. The additional cost of SA-BSI was estimated through a matched case?control study. The economic burden was calculated from the sum of the medical costs, the costs of caregiving and loss of productivity.ResultsThree hundred and thirty nine cases of nosocomial SA-BSI were included in the study: 254 cases of methicillin-resistant SA-BSI (MRSA-BSI) and 85 cases of methicillin-susceptible SA-BSI (MSSA-BSI). Death related to BSI occurred in 81 cases (31.9%) of MRSA-BSI and 12 cases (14.1%) of MSSA-BSI. The estimated incidence of nosocomial MRSA-BSI was 0.12/1,000 patient-days and that of nosocomial MSSA-BSI, 0.04/1,000 patient-days. The estimated annual cases of nosocomial BSI were 2,946 for MRSA and 986 for MSSA in South Korea. The additional economic burden per case of nosocomial SA-BSI was US

Differences in characteristics between healthcare-associated and community-acquired infection in community-onset Klebsiella pneumoniae bloodstream infection in Korea

20,494 for MRSA-BSI and