Response System for and Epidemiological Features of COVID-19 in Gyeongsangnam-do Province in South Korea.

BACKGROUND: The South Korean government has been combating the coronavirus disease 2019 (COVID-19) outbreak using public information and extensive viral screening. We describe the application of the Korean response system in Gyeongsangnam-do province and outline the epidemiological features of COVID-19 in the cohort. METHODS: A Rapid Response Team tracked the patients' activities and identified close contacts. A Patient Management Team made decisions regarding the severity of illness, hospital allocation depending on severity, and time of discharge. A national medical center with 155 beds and 4 university-affiliated hospitals with 48 negative-pressure isolation rooms were dedicated for patients with COVID-19. RESULTS: As of 15 April, 17 400 residents were tested, of whom 111 were confirmed positive cases. Of the 111 patients, 78 were cured and discharged, 2 recovered after mechanical ventilation, and none died. One healthcare worker at the national center tested positive for SARS-CoV-2. All 412 staff members at the center were tested, but there were no additional infections. Cough (30.0%) was the most common initial symptom, whereas anosmia and ageusia were the first symptoms in 14.7% and 15.7% of the patients, respectively. Overall, 25 patients (22.5%) reported having no symptoms at admission and 7 (6.3%) remained asymptomatic at discharge. CONCLUSIONS: A response system that enabled the early detection of COVID-19 cases, including asymptomatic and presymptomatic cases, and timely quarantine of these patients and their contacts, along with efficient allocation of medical resources, was the key to curbing the COVID-19 outbreak in Gyeongsangnam-do Province.

Clinical Features of Adult COVID-19 Patients without Risk Factors before and after the Nationwide SARS-CoV-2 B.1.617.2 (Delta)-variant Outbreak in Korea: Experience from Gyeongsangnam-do.

BACKGROUND: Data on severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) delta variant virulence are insufficient. We retrospectively compared the clinical features of adult coronavirus disease 2019 (COVID-19) patients without risk factors for severe COVID-19 who entered residential treatment centers (RTCs) before and after the delta variant outbreak. METHODS: We collected medical information from two RTCs in South Korea. On the basis of nationwide delta variant surveillance, we divided the patients into two groups: 1) the delta-minor group (diagnosed from December 2020-June 2021, detection rate < 10%) and 2) the delta-dominant group (diagnosed during August 2021, detection rate > 90%). After propensity-score matching, the incidences of pneumonia, hospital transfer and need for supplemental oxygen were compared between the groups. In addition, risk factors for hospital transfer were analysed. RESULTS: A total of 1,915 patients were included. The incidence of pneumonia (14.6% vs. 9.2%, P = 0.009), all-cause hospital transfer (10.4% vs. 6.3%, P = 0.020) and COVID-19-related hospital transfer (7.5% vs. 4.8%, P = 0.081) were higher in the delta-dominant group than those in the delta-minor group. In the multivariate analysis, the delta-dominant group was an independent risk factor for all-cause (adjusted odds ratio [aOR], 1.91; 95% confidence interval [CI], 1.16-3.13; P = 0.011) and COVID-19-related hospital transfer (aOR, 1.86; 95% CI, 1.04-3.32; P = 0.036). CONCLUSION: Hospitalization rates were increased in the adult COVID-19 patients during the delta variant nationwide outbreak. Our results showed that the delta variant may be more virulent than previous lineages.

Successful control of an extended-spectrum beta-lactamase-producing Klebsiella pneumoniae ST307 outbreak in a neonatal intensive care unit.

BACKGROUND: In this study, we evaluated the genetic relatedness of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBL-KPN) isolates from an outbreak in a neonatal intensive care unit (NICU) in August 2017, We implemented an active countermeasure to control this outbreak successfully. METHODS: The incidence of healthcare-associated ESBL-KPN bacteremia was evaluated before and after initiating enhanced infection control (IC) practices in January 2018. Surveillance cultures were set up and monitored for neonates, medical personnel, and NICU environments. Molecular analyses, including pulse-field gel electrophoresis (PFGE), sequence typing, and ESBL genotyping, were performed for the isolated KPN strains. RESULTS: After implementing the enhanced IC procedures, the healthcare-associated bacteremia rate decreased from 6.0 to 0.0 per 1000 patient-days. Samples from neonates (n = 11/15, 73.3%), medical personnel (n = 1/41, 2.4%), and medical devices and the environments (6/181, 3.3%) tested positive for ESBL-KPN in the surveillance cultures in December 2017. Active surveillance cultures revealed that 23 of 72 neonates who were screened (31.9%) were colonized with ESBL-KPN between January and March 2018. All the isolates demonstrated closely related PFGE patterns and were identified as ST307 strain carrying the CTX-M-15 gene. CONCLUSIONS: Contaminated NICU environments and medical devices, as well as transmission by medical personnel, appeared to be the source of the outbreak of ESBL-KPN infection. We employed an enhanced IC strategy during January-March 2018 and successfully controlled the clonal outbreak of CTX-M-15-positive KPN. ST307 has emerged as an important bacteremia-causing pathogen in the NICU and should be carefully monitored.

Veno-Arterial-Venous Extracorporeal Membrane Oxygenation in a Critically Ill Patient with Coronavirus Disease 2019.

Patients with cardiopulmonary failure may not be fully supported with typical configurations of extracorporeal membrane oxygenation (ECMO), either veno-arterial (VA) or veno-venous (VV). Veno-arterial-venous (VAV)-ECMO is a technique used to support the cardiopulmonary systems during periods of inadequate gas exchange and perfusion. In the severe case of coronavirus disease 2019 (COVID-19), which simultaneously affects the heart and lung, VAV-ECMO may improve a patient's recovery potential. We report the case of a 72-year-old woman with acute respiratory distress syndrome and circulatory failure following COVID-19, who was treated with VAV-ECMO.

Clinical and Molecular Characteristics of qacA- and qacB-Positive Methicillin-Resistant Staphylococcus aureus Causing Bloodstream Infections.

The increasing use of chlorhexidine for methicillin-resistant Staphylococcus aureus (MRSA) decolonization has raised concerns about the emergence of resistance to these agents. However, the clinical significance of MRSA positive for the qacA and qacB chlorhexidine tolerance genes has not been established. We investigated the clinical features and predictive factors of MRSA bloodstream infection (BSI) isolates, caused by qacA- and qacB-positive MRSA, from 2010 to 2016 at a tertiary hospital in South Korea. A total of 246 MRSA BSI isolates were included; 71 (28.9%) isolates carried qacA/B The annual frequency of qacA- and qacB-positive MRSA bacteremia did not change significantly over the study period. Patients infected with qacA- and qacB-positive MRSA had common risk factors for health care-associated infections, including prior antibiotic use, central venous catheterization in situ, intensive care unit-acquired bacteremia, and nosocomial infection. The qacA- and qacB-positive isolates were also associated with an increasing chlorhexidine MIC and resistance to non-ß-lactam antibiotics. The qacA- and qacB-positive isolates were more likely to belong to sequence type 5 (ST5), which is a common health care-associated MRSA strain in South Korea. In multivariable analyses, qacA- and qacB-positive MRSA isolates were found to be associated with agr dysfunction (adjusted odds ratio [aOR], 6.45; 95% confidence interval [CI], 2.59 to 16.10), ST5 MRSA strain (aOR, 4.96; 95% CI, 1.85 to 13.26), nosocomial infection (aOR, 4.88; 95% CI, 2.20 to 10.83), and antibiotic use within the previous 3 months (aOR, 2.59; 95% CI, 1.20 to 5.59). These findings suggest that the microbiological features of qacA and qacB carriage provide a selective advantage for specific MRSA strains in hospital environments.

Impact of health care-associated community-onset cellulitis in Korea: a multicenter study.

We conducted a multicenter study to determine the clinical and microbiological characteristics of health care-associated (HCA) cellulitis in Korea. We retrospectively reviewed the medical records of patients who had been diagnosed with community-onset cellulitis. Of the 2208 cellulitis patients, 232 (10.5%) had HCA cellulitis, 1243 (56.3%) patients were hospitalized, and 15 (0.7%) died in hospital. Compared with community-acquired (CA) cellulitis, patients with HCA cellulitis were older and more frequently presented with comorbidity and septic shock. A total of 355 microorganisms were isolated from 314 patients (14.2%). Staphylococcus aureus (134 isolates) was the most common organism, followed by Streptococcus spp. (86 isolates) and Gram-negative fermenters (58 isolates). Methicillin-resistant S. aureus (MRSA) accounted for 29.1% (39/134) of S. aureus infections. None of the Gram-negative fermenters were resistant to carbapenem. The antibiotic susceptibility pattern of isolated microorganisms was not different between HCA and CA cellulitis. In patients with HCA cellulitis, S. aureus (11.2% [26/232] vs. 5.5% [108/1976], p = 0.001), including MRSA (4.3% [10/232] vs. 1.5% [29/1976], p = 0.003) and Gram-negative fermenters (6.0% [14/232] vs. 2.3% [44/1976], p = 0.002), were more common causative organisms than in CA-cellulitis patients. Age ≥ 65 years, septic shock, and HCA infection were statistically significant factors associated with in-hospital mortality.

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 patient's 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.

Therapeutic outcomes of hematogenous vertebral osteomyelitis with instrumented surgery.

BACKGROUND: Patients with hematogenous vertebral osteomyelitis (HVO) occasionally require instrumentation for spinal stabilization. However, placing instrumentation in the setting of spinal infection raises concerns about recurrent infection due to bacteria adhering to the foreign material. In this study, we evaluated the therapeutic outcomes of patients with HVO who underwent instrumented surgery. METHODS: We conducted a retrospective chart review of adult patients with microbiologically diagnosed HVO who underwent surgical intervention in 5 tertiary care hospitals over an 8-year period. RESULTS: A total of 153 patients with HVO underwent surgical management for their infections. Of these 153 patients, 94 (61.4%) underwent surgical debridement alone (noninstrumented surgery) and 59 (38.6%) underwent surgical debridement and instrumentation (instrumented surgery). The median durations of antibiotic therapy were 66 and 80 days for the noninstrumentation and instrumentation groups, respectively (P = .22). Clinical outcomes were similar between the groups, including rates of infection-related death (2.1% vs 0%; P = .52), primary failure (1.1% vs 5.1%; P = .30), and recurrence (4.8% vs 6.8%; P = .72). Among the instrumentation group, there was a significant decreasing trend for recurrence according to total duration of antibiotic therapy: 22.2% (4-6 weeks), 9.1% (6-8 weeks), and 2.6% (≥ 8 weeks; P = .04). Duration of pre-instrumentation antibiotic therapy and single-stage operation (vs 2-stage operation) were not risk factors for recurrence. CONCLUSIONS: Spinal instrumentation in patients with HVO may be safe with pathogen-directed prolonged antibiotic therapy and should not be abandoned or delayed solely because of the risk of recurrence.

Effects of sub-inhibitory concentrations of nafcillin, vancomycin, ciprofloxacin, and rifampin on biofilm formation of clinical methicillin-resistant Staphylococcus aureus.

Methicillin-resistant Staphylococcus aureus (MRSA) infections are often difficult to treat because of their biofilm-forming ability and antimicrobial resistance. We investigated the effects of sub-minimal inhibitory concentrations (MICs) of antibiotics on MRSA biofilm formation. Clinical MRSA isolates were grown with sub-MICs (1/256-1/2 × MICs) of nafcillin, vancomycin, ciprofloxacin, and rifampin. The biofilm biomass was measured using crystal violet staining. Of the 107 MRSA isolates tested, 63 (58.9%) belonged to sequence type 5 (ST5), and 44 (41.1%) belonged to ST72. The MIC50/MIC90 values of nafcillin, vancomycin, ciprofloxacin, and rifampin were 256/512, 1/2, 64/512, and 0.008/0.03 mg/L, respectively. The sub-MICs of nafcillin, vancomycin, ciprofloxacin, and rifampin promoted biofilm formation in 75 (70.1%), 49 (45.8%), 89 (83.2%), and 89 (83.2%) isolates, respectively. At sub-MICs of nafcillin, the factors associated with strong biofilm induction were the ST5 strain (P = 0.001) and agr dysfunction (P = 0.005). For the sub-MICs of ciprofloxacin, the associated factors were the ST5 strain (P = 0.002), staphylococcal protein A type t002 strain (P < 0.001), and ciprofloxacin resistance (P < 0.001). Among the sub-MICs of rifampin, only ST5 was associated with strong biofilm induction (P = 0.006). Because the sub-MICs of rifampin were much lower than clinically relevant concentrations, we further tested the capability of biofilm induction in 0.03[Formula: see text]32 mg/L of rifampin. At these concentrations, rifampin-induced biofilm formation was rare in rifampin-susceptible MRSA [1.0% (1 of 100)] but common in rifampin-resistant MRSA [71.4% (5 of 7), P < 0.001]. Induction of biofilm biomass at sub-MICs of antibiotics is common in clinical MRSA isolates and is differentially affected by the MRSA strain and antibiotic class. IMPORTANCE: Bacteria can be exposed to sub-MICs of antibiotics at the beginning and end of a dosing regimen, between doses, or during low-dose therapies. Growing evidence suggests that sub-MICs of antimicrobials can stimulate MRSA biofilm formation and alter the composition of the biofilm matrix. Pevious studies have found that sub-MICs of oxacillin, methicillin, and amoxicillin promote biofilm formation in some community-acquired MRSA (CA-MRSA). We evaluated biofilm induction by sub-MICs of four different classes of antibiotics in 44 CA-MRSA and 63 healthcare-associated MRSA (HA-MRSA) strains. Our study indicated that sub-MICs of nafcillin, vancomycin, ciprofloxacin, and rifampin frequently promote biofilm induction in clinical MRSA isolates. Strong biofilm induction in sub-MICs of nafcillin, ciprofloxacin, and rifampin was more frequent in HA-MRSA than in CA-MRSA. Antibiotic-induced biofilm formation depends on the antibiotic class, MRSA strain, and antibiotic resistance. Our results emphasize the importance of maintaining effective bactericidal concentrations of antibiotics to treat biofilm-related infections.

Viral infection in patients with severe pneumonia requiring intensive care unit admission.

RATIONALE: The role of viruses in pneumonia in adults and the impact of viral infection on mortality have not been elucidated. Previous studies have significant limitations in that they relied predominantly on upper respiratory specimens. OBJECTIVES: To investigate the role of viral infection in adult patients with pneumonia requiring intensive care unit (ICU) admission. METHODS: A retrospective analysis of a prospective cohort was conducted in a 28-bed medical ICU. Patients with severe community-acquired pneumonia (CAP) or healthcare-associated pneumonia (HCAP) were included in the study. MEASUREMENTS AND MAIN RESULTS: A total of 198 patients (64 with CAP, 134 with HCAP) were included for analysis. Of these, 115 patients (58.1%) underwent bronchoscopic bronchoalveolar lavage (BAL), 104 of whom were tested for respiratory viruses by BAL fluid reverse-transcription polymerase chain reaction (RT-PCR). Nasopharyngeal specimen RT-PCR was performed in 159 patients (84.1%). Seventy-one patients (35.9%) had a bacterial infection, and 72 patients (36.4%) had a viral infection. Rhinovirus was the most common identified virus (23.6%), followed by parainfluenza virus (20.8%), human metapneumovirus (18.1%), influenza virus (16.7%), and respiratory syncytial virus (13.9%). Respiratory syncytial virus was significantly more common in the CAP group (CAP, 10.9%; HCAP, 2.2%; P = 0.01). The mortalities of patients with bacterial infections, viral infections, and bacterial-viral coinfections were not significantly different (25.5, 26.5, and 33.3%, respectively; P = 0.82). CONCLUSIONS: Viruses are frequently found in the airway of patients with pneumonia requiring ICU admission and may cause severe forms of pneumonia. Patients with viral infection and bacterial infection had comparable mortality rates.

The Significance of FilmArray Blood Culture Identification Panel (FA-BCID) for Managing Patients with Positive Blood Cultures.

We analyzed the accuracy and time efficiency of the FilmArray blood culture identification (FA-BCID) panel in identifying the pathogens in positive blood cultures. Two-hundred and seventy-two individuals were randomly assigned as the control (n = 212) and FA-BCID (n = 60) groups participating in this study. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to assess the control group. Meanwhile, the FA-BCID group was evaluated using both FA-BCID and MALDI-TOF, and the results were compared. The identification results from 73% (44/60) of the blood samples demonstrated agreement between FA-BCID and MALDI-TOF. The FA-BCID panel detected mecA genes in seven Staphylococcus species; six cases were confirmed using antimicrobial susceptibility testing. In addition, KPC genes were detected in one Escherichia coli and one Klebsiella pneumoniae, although only the latter corresponded with the result from antimicrobial susceptibility testing. The turnaround time (TAT) for identification through FA-BCID was shorter, with a median of 3.6 [2.4-4.6] hours (p < 0.05). No significant differences in the clinical and microbial outcomes following the ASP were observed between FA-BCID and MALDI-TOF. These results suggest that the FA-BCID panel provides an identification result that is as reliable as that provided by the routine identification procedure but with shorter TAT; thus, the FA-BCID method is considered an effective and beneficial method for therapeutic decision making and the improvement of the ASP for patients with bloodstream infection.

Real World Experience with Regdanvimab Treatment of Mild-to-Moderate Coronavirus Disease-19 in a COVID-19 Designated Hospital of Korea.

BACKGROUND: Real-world clinical data concerning regdanvimab, a monoclonal antibody treatment for patients with mild-to-moderate coronavirus disease 2019 (COVID-19), are urgently needed. Here, we describe our experience with regdanvimab. MATERIALS AND METHODS: This retrospective cohort study enrolled high-risk adults with mild-to-moderate COVID-19 who were admitted to a dedicated COVID-19 hospital in Korea from March to September 2021. We used multiple logistic regression and propensity score-matching to compare the outcomes of patients who did or did not receive regdanvimab. The primary outcome was in-hospital progression to severe or critical status, or death. RESULTS: Of 586 patients eligible for regdanvimab, 256 patients who received regdanvimab and 251 untreated patients were included. The median age was 66 years and 47.5% were men. The most common underlying illnesses were hypertension (53.8%) and diabetes (36.9%). Patients were admitted to the hospital at a median of 2 days after symptom onset; regdanvimab was administered at a median of 3 days after symptom onset. Multivariate analysis indicated that regdanvimab significantly reduced the risk of disease progression during hospitalization [odds ratio (OR): 0.285; 95% confidence interval (CI): 0.144 - 0.564]. In a 1:1 propensity score-matched cohort (172 patients in either group), regdanvimab also decreased the risk of progression (OR: 0.162; 95% CI: 0.068 - 0.386). CONCLUSION: In high-risk patients with mild-to-moderate COVID-19, regdanvimab decreased the risk of progression to severe COVID-19.

Clinical significance of Propionibacterium acnes recovered from blood cultures: analysis of 524 episodes.

Of 522 patients with Propionibacterium acnes bacteremia (PAB), 18 (3.5%) had clinically significant PAB. Of these 18 patients, 10 (55.6%) had hospital-acquired bacteremia and 6 (33.3%) had undergone invasive procedures before development of PAB. One patient with a ventricular septal defect presented with infective endocarditis. After the exclusion of 1 patient whose outcome was not available, the overall mortality rate was 5.9% (1/17).

Chest computed tomography is more likely to show latent tuberculosis foci than simple chest radiography in liver transplant candidates.

Although the detection and treatment of latent tuberculosis infections (LTBIs) in transplant candidates are essential, current diagnostic methods for LTBIs are limited, especially in immunocompromised subjects. Pretransplant chest computed tomography (CT) may reveal more LTBI foci and thus predict the development of posttransplant tuberculosis (TB) more efficiently; however, this hypothesis has not yet been investigated. Thirty-six liver transplantation (LT) recipients who developed TB (the TB group) and 144 LT recipients who did not develop TB (the control group) were retrospectively enrolled into a study with a nested case-control design, and their clinical characteristics and radiological findings were compared. Tuberculin skin tests (TSTs) were not performed, and none of these patients had been treated for LTBIs. Thirty-six of 2549 LT recipients (1.4%) were diagnosed with TB after LT (median = 10 months, range = 1-80 months). Twenty-eight patients (77.8%) successfully completed the treatment. There were no significant differences in the clinical characteristics of the 2 groups. Abnormal CT findings (40.0% versus 17.3%, P = 0.018) and chest X-ray (CXR) findings (25.0% versus 11.8%, P = 0.044) suggestive of healed TB were significantly more frequent in the TB group versus the control group. Of the 10 patients who underwent chest CT and developed TB, 5 (50%) showed abnormal findings only on chest CT scans, whereas their CXR results were normal. In conclusion, a pretransplant chest CT scan is more likely to show an LTBI than a CXR in those with post-LT TB. The usefulness of chest CT along with traditional methods such as TSTs for LTBI screening should be further investigated.

Preterm Twins Born to a Mother with Miliary Tuberculosis: Importance of Early Recognition and Prompt Response in Infection Control to Manage Congenital Tuberculosis Exposure in a Neonatal Intensive Care Unit.

Delayed diagnosis of congenital tuberculosis (TB) in the neonatal intensive care unit (NICU) is a serious problem in terms of infection control. Here, we report our preemptive infection control activities implemented after the diagnosis of miliary TB in a mother of preterm twins (index twins, NB1 and NB2) in the NICU. In addition, we reviewed previous case reports of congenital TB exposure in the NICU setting. Immediately after diagnosing miliary TB in the mother, the index twins were isolated before their TB diagnosis and received preemptive anti-TB medication; contact investigations were also conducted. Eventually, NB1 was diagnosed with congenital TB at 29 days of age, and NB2 showed no definite evidence of TB. Through contact investigation, 11 of the 16 exposed infants received isoniazid prophylaxis and no positive tuberculin skin test results were obtained after 3 months. One of the 31 exposed healthcare workers showed new interferon-gamma release assay conversion. Moreover, our case showed a much shorter contagious period compared to that in previous reports (8 versus 17-102 days). This suggests that a high index of suspicion and prompt measures can help prevent congenital TB outbreaks and reduce the burden of infection control activities in the NICU.

Etiology, Characteristics, and Outcomes of Community-Onset Pyomyositis in Korea: A Multicenter Study.

BACKGROUND: Pyomyositis (PM) is a serious soft tissue infection and despite its clinical importance, previous studies have not been able to fully determine the clinical characteristics and microbial epidemiology of PM in Korea, which we therefore aimed to investigate. MATERIALS AND METHODS: We retrospectively identified 140 adult patients diagnosed with PM from 13 general hospitals between January 2012 and December 2015. We analyzed the clinical and microbial characteristics of community-onset PM and compared them with community-acquired (CA) and healthcare-associated (HCA) PM. RESULTS: One hundred eleven organisms were isolated from 96 (68.6%) patients with PM. Staphylococcus aureus (38 patients) was the most common pathogen, followed by streptococci (24 patients), and enteric Gram-negative organisms (27 patients). Methicillin-resistant S. aureus (MRSA) was identified in four (2.9%) patients and in-hospital mortality reached 8.6% (12/140). Enterococci isolates were identified in the HCA PM subgroup only The proportion of MRSA isolates was not comparable between CA and HCA PM subgroups. In the 83 patients with PM infected by monomicrobial pathogens, isolates of Gram-negative organisms were more commonly found in HCA PM subgroup than in CA PM subgroup (47.6% [10/21] of patients with HCA PM vs. 20.7% [12/58] of patients with CA PM; P = 0.01). CONCLUSION: Gram-positive cocci such as S. aureus and streptococci were dominant etiologies in community-onset PM, whereas MRSA appears to an uncommon causative organism of PM in Korea. Enteric Gram-negative organisms should also be considered as major etiologies, especially in HCA PM patient population in Korea.

Clinical impact of early reinsertion of a central venous catheter after catheter removal in patients with catheter-related bloodstream infections.

OBJECTIVE: Early replacement of a new central venous catheter (CVC) may pose a risk of persistent or recurrent infection in patients with a catheter-related bloodstream infection (CRBSI). We evaluated the clinical impact of early CVC reinsertion after catheter removal in patients with CRBSIs. METHODS: We conducted a retrospective chart review of adult patients with confirmed CRBSIs in 2 tertiary-care hospitals over a 7-year period. RESULTS: To treat their infections, 316 patients with CRBSIs underwent CVC removal. Among them, 130 (41.1%) underwent early CVC reinsertion (≤3 days after CVC removal), 39 (12.4%) underwent delayed reinsertion (>3 days), and 147 (46.5%) did not undergo CVC reinsertion. There were no differences in baseline characteristics among the 3 groups, except for nontunneled CVC, presence of septic shock, and reason for CVC reinsertion. The rate of persistent CRBSI in the early CVC reinsertion group (22.3%) was higher than that in the no CVC reinsertion group (7.5%; P = .002) but was similar to that in the delayed CVC reinsertion group (17.9%; P > .99). The other clinical outcomes did not differ among the 3 groups, including rates of 30-day mortality, complicated infection, and recurrence. After controlling for several confounding factors, early CVC reinsertion was not significantly associated with persistent CRBSI (OR, 1.59; P = .35) or 30-day mortality compared with delayed CVC reinsertion (OR, 0.81; P = .68). CONCLUSIONS: Early CVC reinsertion in the setting of CRBSI may be safe. Replacement of a new CVC should not be delayed in patients who still require a CVC for ongoing management.

Rapid diagnosis of tuberculous meningitis by T cell-based assays on peripheral blood and cerebrospinal fluid mononuclear cells.

BACKGROUND: The role of the new Myocbacterium tuberculosis-specific enzyme-linked immunosorbent spot (ELISPOT) assay for diagnosis of tuberculous meningitis (TBM) has not yet been fully assessed. Here, we conducted a prospective, blinded, observational study to evaluate the diagnostic accuracy of this assay, compared with the conventional tests, for diagnosing TBM. METHODS: All adult patients with suspected TBM were enrolled at a tertiary care hospital (Seoul, South Korea) during a 12-month period. ELISPOT assays were performed on peripheral mononuclear cells and mononuclear cells from cerebrospinal fluid (CSF). RESULTS: Eighty-nine patients with suspected TBM were enrolled. Of these, 31 (35%) were classified as having TBM (10 confirmed, 6 highly probable, and 15 probable cases), and 55 (62%) were classified as not having active tuberculosis. The remaining 3 (3%) with possible TBM were excluded from the final analysis. The sensitivities and specificities, respectively, of the tested methods for diagnosing TBM were as follows: CSF adenosine deaminase level >5.8 U/L, 89% (95% confidence interval [CI], 69%-98%) and 73% (95% CI, 58%-84%); peripheral mononuclear cells ELISPOT, 71% (95% CI, 51%-86%) and 57% (95% CI, 42%-70%); and CSF mononuclear cells ELISPOT assay, 59% (95% CI, 36%-79%) and 89% (95% CI, 72%-98%). The combined sensitivity of an adenosine deaminase level >5.8 U/L or a positive peripheral mononuclear cells ELISPOT assay result was 94% (95% CI, 79%-99%), conferring a negative likelihood ratio of 0.14 (95% CI, 0.03-0.55) when both test results were negative. CONCLUSION: ELISPOT assays using peripheral mononuclear cells and CSF mononuclear cells are useful adjuncts to the current tests for diagnosing TBM, particularly when used in combination with the assessment of adenosine deaminase level in CSF.