In-Gyu Bae

The possible role of cerebrospinal fluid adenosine deaminase activity in the diagnosis of tuberculous meningitis in adults

We studied an adenosine deaminase (ADA) activity in the cerebrospinal fluid (CSF) of 182 patients with meningitis. The patients were subdivided into four groups, (1) 36 cases of tuberculous meningitis; (2) 130 cases of viral or aseptic meningitis; (3) nine cases of bacterial meningitis; (4) seven cases of cryptococcal meningitis. Mean+/-S.D. ADA activity was 12.76+/-7.53 U/l in group 1; 2.58+/-2.37 U/l in group 2; 7.38+/-3.27 U/l in group 3; 7.42+/-4.38 U/l in group 4. Comparing the ADA activity in each group with the other groups, the difference is significant (P<0.001), except between groups 3 and 4. The sensitivity of the test for group 1 compared with group 2 was 0.83 and the specificity was 0.95 when a cut-off value of 7 U/l was used. When group 1 was compared with groups 3 and 4, the sensitivity was 0.58 and the specificity was 0.89 and 0.71 with groups 3 and 4, respectively, when a cut-off value of 10 U/l was used. Values >15 U/l were not observed in any of the non-tuberculous meningitis patients; therefore, ADA activity >15 U/l could be a strong indication of tuberculous meningitis. We conclude that a determination of CSF ADA can aid in the early differential diagnosis of tuberculous meningitis.

Hospital outbreak of Burkholderia stabilis bacteraemia related to contaminated chlorhexidine in haematological malignancy patients with indwelling catheters

Burkholderia cepacia complex (BCC) is an opportunistic pathogen that occasionally causes hospital outbreaks. This paper describes an outbreak of BCC bacteraemia in haematological malignancy patients related to a contaminated chlorhexidine gluconate solution. Eight BCC isolates were obtained from patients hospitalised in the same ward of a cancer centre in a Korean hospital. A further three BCC isolates were obtained from 0.5% chlorhexidine gluconate used in the same ward. The isolates were identified as B. stabilis and exhibited identical pulsed-field gel electrophoresis profiles. All patients with B. stabilis bacteraemia had indwelling intravenous catheters, which were treated with chlorhexidine to disinfect the catheters. Following identification of the source of contamination, strict controls regarding surveillance cultures for disinfectants have been enforced. No further B. stabilis infections have been found in the hospital.

Genetic correlation of community-associated methicillin-resistant Staphylococcus aureus strains from carriers and from patients with clinical infection in one region of Korea.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is an increasingly common worldwide and colonizing S. aureus strains may serve as the causative pathogen for overt clinical infections. This study was performed to determine whether the pathogenic CA-MRSA isolate in clinical infections was genetically related to the MRSA isolates in community carriers. We prospectively collected a total of 42 CA-MRSA isolates (23 clinical infection isolates and 19 colonization isolates) in a local region of Korea. Antimicrobial susceptibility tests, staphylococcal toxin assays, SCCmec typing, multilocus sequence typing (MLST), and spa (staphylococcal protein A) typing were performed with all isolates. Thirty-four (81%) of 42 CA-MRSA isolates belonged to sequence type (ST) 72 in the MLST analysis. The distribution of STs did not differ significantly between colonization and clinical infection isolates (89.5% [17/19] vs. 73.9% [17/23], P=0.26). Among the ST72-MRSA isolates, spa type t664 (18, 52.9%) and t324 (8, 23.5%) were common in both groups. This study demonstrates that the community-associated MRSA strains from patients with clinical infections are closely related to the strains found in carriers from one local community.

Severe Fever with Thrombocytopenia Syndrome in South Korea, 2013-2015

Background Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that was recently identified in China, South Korea and Japan. The objective of the study was to evaluate the epidemiologic and clinical characteristics of SFTS in South Korea. Methods/Principal Findings SFTS is a reportable disease in South Korea. We included all SFTS cases reported to the Korea Centers for Disease Control and Prevention (KCDC) from January 2013 to December 2015. Clinical information was gathered by reviewing medical records, and epidemiologic characteristics were analyzed using both KCDC surveillance data and patient medical records. Risk factors for mortality in patients with SFTS were assessed. A total of 172 SFTS cases were reported during the study period. SFTS occurred throughout the country, except in urban areas. Hilly areas in the eastern and southeastern regions and Jeju island (incidence, 1.26 cases /105 person-years) were the main endemic areas. The yearly incidence increased from 36 cases in 2013 to 81 cases in 2015. Most cases occurred from May to October. The overall case fatality ratio was 32.6%. The clinical progression was similar to the 3 phases reported in China: fever, multi-organ dysfunction, and convalescence. Confusion, elevated C-reactive protein, and prolonged activated partial thromboplastin times were associated with mortality in patients with SFTS. Two outbreaks of nosocomial SFTS transmission were observed. Conclusions SFTS is an endemic disease in South Korea, with a nationwide distribution and a high case-fatality ratio. Confusion, elevated levels of C-reactive protein, and prolonged activated partial thromboplastin times were associated with mortality in patients with SFTS.

Clinical characteristics and outcomes of hematogenous vertebral osteomyelitis caused by gram-negative bacteria

OBJECTIVE To evaluate the clinical characteristics and outcomes of patients with hematogenous vertebral osteomyelitis (HVO) caused by gram-negative bacteria (GNB). METHODS We conducted a retrospective chart review of adult patients with HVO from three tertiary-care hospitals over a 7-year period. RESULTS Of the 313 microbiologically diagnosed HVO cases, GNB was responsible for 65 (20.8%) cases. Compared with patients with MSSA HVO, patients with GNB HVO were more likely to be female (P = 0.03) and have diabetes (P = 0.03), but less likely to have epidural abscess (P = 0.02) and paravertebral abscess (P = 0.003). Clinical outcomes were similar between the GNB and MSSA groups, including in-hospital mortality (4.6% vs. 7.8%; P = 0.53), recurrence (9.7% vs. 4.3%; P = 0.20), and sequelae (31.7% vs. 32.2%; P = 0.95). Among GNB-infected patients, recurrence rates differed according to the total duration of antibiotic treatment: 40.0% (4-6 weeks), 33.3% (6-8 weeks), and 2.1% (≥ 8 weeks) (P = 0.002). CONCLUSIONS GNB HVO was responsible for 20.8% of adult cases of HVO. Despite some differences in clinical and radiological presentation, clinical outcomes were similar between GNB and MSSA HVO. Antibiotic therapy for ≥ 8 weeks may benefit patients with GNB HVO.

Prevalence of Latent Tuberculosis Infection among Health Care Workers in South Korea: A Multicenter Study

Background We investigated the prevalence of latent tuberculosis infection (LTBI) among the health care workers (HCWs) and analyzed its risk factors in South Korea. Methods A standard questionnaire regarding the baseline demographics and risk factors for LTBI was given to each participant and tuberculin skin test (TST), QuantiFERON-TB GOLD In-Tube (QFT-GIT) assay, and chest radiography were performed. Results A total of 493 participants, 152 (30.8%) doctors and 341 (69.2%) nurses were enrolled in eight tertiary referral hospitals. The mean age of the subjects was 30.6 years old, and 383 (77.7%) were female. Of the 152 doctors, 63 (41.4%) and 36 (23.7%) were positive by TST and by QTF-GIT, respectively, and among the 341 nurses, 119 (34.9%) and 49 (14.4%) had positive TST and QFT-GIT results, respectively. Overall, the agreement between the two tests was 0.22 by the chance corrected proportional agreement rate (kappa coefficient) in 493 subjects. Experience of working in tuberculosis (TB)-related departments was significantly associated with positive LTBI test results by QFT-GIT assay, not by TST. In multivariate analysis, only age was independently associated with increased risk of a positive TST result, while age and experience of working in TB-related departments (odds ratio, 2.29; 95% confidence interval, 1.01-5.12) were independently associated with increased risk of a positive QFT-GIT result. Conclusion A high prevalence of LTBI was found among South Korean HCWs. Considering the association between the experience of working in TB-related departments and high risk of LTBI, QFT-GIT may be a better diagnostic test for LTBI than TST in HCWs.

Clinical Evaluation of BacT/Alert FA Plus and FN Plus Bottles Compared with Standard Bottles

ABSTRACT The performance of the BacT/Alert FA Plus and FN Plus resin bottles was evaluated in comparison with that of standard aerobic (SA) and standard anaerobic (SN) bottles. Twenty milliliters of blood from adult patients was equally distributed into four types of bottles: FA Plus, FN Plus, SA, and SN. The detection of clinically significant organisms and the time to detection (TTD) were monitored for each bottle. Among the 3,103 blood culture sets that were requested, the blood volume of each bottle was over 4 ml in 1,481 sets (47.7%). Among these 1,481 sets, 158 cultures grew in the FA Plus and SA bottles, and 136 grew in the FN Plus and SN bottles. Growth in only one type of bottle was more commonly observed for the FA Plus (n = 38) than for the SA (n = 14) (P = 0.001) bottles and for the FN Plus (n = 27) than for the SN (n = 10) (P = 0.008) bottles. Gram-negative bacilli were more frequently isolated in the resin bottles (P < 0.05). The skin contamination rate was 1.2% in the resin bottles and the standard bottles. The mean TTD was 11.1 h in the FA Plus bottles versus 13.1 h in the SA bottles (P < 0.001) and 12.0 h in the FN Plus bottles versus 12.8 h in the SN bottles (P = 0.083). Clinically significant bacteria, including Gram-negative bacilli, were isolated more frequently from the resin bottles than from the standard bottles. Clinically significant bacteria were detected faster using the aerobic resin bottles than using the standard aerobic bottles. This finding might not be applicable to the standard-practice 10-ml protocol for each bottle because the results from using a smaller volume (5 ml) might be less pronounced.

Optimal Duration of Antibiotic Therapy in Patients With Hematogenous Vertebral Osteomyelitis at Low Risk and High Risk of Recurrence

BACKGROUND The optimal duration of antibiotic treatment for hematogenous vertebral osteomyelitis (HVO) should be based on the patients risk of recurrence, but it is not well established. METHODS A retrospective review was conducted to evaluate the optimal duration of antibiotic treatment in patients with HVO at low and high risk of recurrence. Patients with at least 1 independent baseline risk factor for recurrence, determined by multivariable analysis, were considered as high risk and those with no risk factor as low risk. RESULTS A total of 314 patients with microbiologically diagnosed HVO were evaluable for recurrence. In multivariable analysis, methicillin-resistant Staphylococcus aureus infection (adjusted odds ratio [aOR], 2.61; 95% confidence interval [CI], 1.16-5.87), undrained paravertebral/psoas abscesses (aOR, 4.09; 95% CI, 1.82-9.19), and end-stage renal disease (aOR, 6.58; 95% CI, 1.63-26.54) were independent baseline risk factors for recurrence. Therefore, 191 (60.8%) patients were classified as low risk and 123 (39.2%) as high risk. Among high-risk patients, there was a significant decreasing trend for recurrence according to total duration of antibiotic therapy: 34.8% (4-6 weeks [28-41 days]), 29.6% (6-8 weeks [42-55 days]), and 9.6% (≥8 weeks [≥56 days]) (P = .002). For low-risk patients, this association was still significant but the recurrence rates were much lower: 12.0% (4-6 weeks), 6.3% (6-8 weeks), and 2.2% (≥8 weeks) (P = .02). CONCLUSIONS Antibiotic therapy of prolonged duration (≥8 weeks) should be given to patients with HVO at high risk of recurrence. For low-risk patients, a shorter duration (6-8 weeks) of pathogen-directed antibiotic therapy may be sufficient.

Clinical and Economic Consequences of Failure of Initial Antibiotic Therapy for Patients with Community-Onset Complicated Intra-Abdominal Infections

Objectives Complicated intra-abdominal infection (cIAI) is infection that extends beyond the hollow viscus of origin into the peritoneal space, and is associated with either abscess formation or peritonitis. There are few studies that have assessed the actual costs and outcomes associated with failure of initial antibiotic therapy for cIAI. The aims of this study were to evaluate risk factors and impact on costs and outcomes of failure of initial antibiotic therapy for community-onset cIAI. Methods A retrospective study was performed at eleven tertiary-care hospitals. Hospitalized adults with community-onset cIAI who underwent an appropriate source control procedure between August 2008 and September 2011 were included. Failure of initial antibiotic therapy was defined as a change of antibiotics due to a lack of improvement of the clinical symptoms and signs associated with cIAI in the first week. Results A total of 514 patients hospitalized for community-onset cIAI were included in the analysis. The mean age of the patients was 53.3 ± 17.6 years, 72 patients (14%) had health care-associated infection, and 48 (9%) experienced failure of initial antibiotic therapy. Failure of initial antibiotic therapy was associated with increased costs and morbidity. After adjustment for covariates, patients with unsuccessful initial therapy received an additional 2.9 days of parenteral antibiotic therapy, were hospitalized for an additional 5.3 days, and incurred

Therapeutic Outcomes of Hematogenous Vertebral Osteomyelitis With Instrumented Surgery

3,287 in additional inpatient charges. Independent risk factors for failure of initial antibiotic therapy were health care-associated infection, solid cancer, and APACHE II ≥13. Conclusions To improve outcomes and costs in patients with community-onset cIAI, rapid assessment of health care-associated risk factors and severity of disease, selection of an appropriate antibiotic regimen accordingly, and early infection source control should be performed.