Search

Background: Sporadic measles outbreaks have continued to occur in Korea, mainly in adults in their 20s and 30s, most notably in 2014 and 2019. We here evaluated the possible causes of a low seroprevalance of measles by testing young healthcare workers (HCWs). Materials and Methods: This study was conducted in a 2,743-bed tertiary-care hospital in Seoul between 2020 and 2021. We performed a measles antibody test (chemiluminescence immunoassay), measured the IgM/IgG index ratio, and conducted an avidity test at 1-month after Measles-Mumps-Rubella (MMR) vaccination in HCWs who had been seronegative for measles. Measles vaccination histories were obtained from the national vaccine registry. Results: Of the 3,173 HCWs newly employed in our hospital during the study period, 54 with a negative measles IgG at commencement were enrolled. Thirty six (67%) of these subjects were female, and the median age was 25 years (interquartile range [IQR]: 24 - 27). Fourty nine (91%) showed seroconversion at 1 month after the first vaccination. Of these individuals, 38 received both measles IgM and IgG test, and all had an IgM/IgG index <1. Of the 49 seroconverters, all HCWs showed a high avidity index. According to the national immunization registry, 45 (83%) received at least 2 doses of an MMR vaccination. Conclusion: Secondary vaccine failure may underlie vaccine failure in young Korean adults. HCWs born after 1985 with a negative measles antibody may need only a single dose booster vaccination rather than a 2-dose vaccination regimen. [ABSTRACT FROM AUTHOR]

We investigated the proportion and characteristics of severe Corynebacterium striatum pneumonia in South Korea during 2014-2019. As part of an ongoing observational study of severe pneumonia among adult patients, we identified 27 severe C. striatum pneumonia cases. Most (70.4%) cases were hospital-acquired, and 51.9% of patients were immunocompromised. C. striatum cases among patients with severe hospital-acquired pneumonia (HAP) increased from 1.0% (2/200) during 2014-2015 to 5.4% (10/185) during 2018-2019, but methicillin-resistant Staphylococcus aureus (MRSA) infections among severe HAP cases decreased from 12.0% to 2.7% during the same timeframe. During 2018-2019, C. striatum was responsible for 13.3% of severe HAP cases from which bacterial pathogens were identified. The 90-day mortality rates were similarly high in the C. striatum and MRSA groups. C. striatum was a major cause of severe HAP and had high mortality rates. This pathogen is emerging as a possible cause for severe pneumonia, especially among immunocompromised patients. [ABSTRACT FROM AUTHOR]

배경: We aimed to identify which streptococcal species are closely associated with infective endocarditis (IE) and whether streptococcal species affect mortality in streptococcal IE. 방법: We performed a retrospective cohort study of all patients with streptococcal bloodstream infections (BSI) from 2010 to 2020 in a tertiary hospital in South Korea. We collected echocardiographic results within one month from BSI and compared clinical characteristics of patients with streptococcal BSI according to the diagnosis of IE. We performed multivariable analysis to evaluate risk of IE according to the species in streptococcal BSI and to identify risk factors for mortality in streptococcal IE. 결과: A total of 2737 patients were identified during the study period; 1177 (43%) patients performed echocardiography within one month from BSI, and 174 (6%) were diagnosed with IE. The highest IE prevalence was found with Streptococcus mutans (33% [9/27]) followed by S. sanguinis (31% [20/64]), S. gordonii (23% [5/22]), S. gallolyticus (16% [12/77]), and S. oralis (12% [14/115]) (Figure). In multivariable analysis, previous IE, high-grade BSI, native valve disease, prosthetic valve disease, congenital heart disease, and community-onset BSI were independent risk factors for IE. After adjusting for these risk factors, S. pneumoniae (adjusted OR [aOR] 0.23; 95% confidence interval [CI] 0.08-0.54), S. constellatus (aOR 0.37; 95% CI 0.12-0.88), S. sanguinis (aOR 7.75; 95% CI 3.64-16.00), S. gallolyticus (aOR 2.57; 95% CI 1.12-5.43), and S. mutans (aOR 5.50; 95% CI 1.83-15.70) were significantly associated with IE. Age, community-onset BSI, ischemic heart disease, and chronic kidney disease were independent risk factors for mortality in streptococcal IE. Streptococcal species did not affect mortality. 결론: Our study suggests significant differences in the prevalence of IE in streptococcal BSI according to the species, although species did not affect mortality in streptococcal IE. [ABSTRACT FROM AUTHOR]

배경: The sequence type 72 (ST72) is the predominant community-associated methicillin-resistant Staphylococcus aureus (MRSA) genotype in South Korea, replacing hospital clones as well as the community. During this change, we assessed the clinical characteristics of methicillin-susceptible and methicillin-resistant ST72 isolates causing bacteremia for better understanding of ST72 S. aureus in South Korea. 방법: We retrospectively collected data on patients with S. aureus bacteremia (SAB) who were admitted at a tertiary hospital in South Korea between March 2007 and December 2018. The ST72 isolates were identified by multilocus sequence typing (MLST). The clinical characteristics and outcomes of patients with methicillin-susceptible ST72 and those with methicillin-resistant ST72 were compared. 결과: A total 442 patients with ST72 SAB were identified, of which 157 (35.5%) were infected with methicillin-susceptible S. aureus (MSSA) and 285 (64.5%) were infected with MRSA. Community-onset infections were higher in the MSSA group compared to the MRSA group (20.4% vs. 10.2%, p=0.004), but the majority of infections occurred in healthcare-associated settings in both groups. MRSA isolates were likely to have multi-drug resistance and higher vancomycin MIC relative to the MSSA isolates. The main infection foci, infection severity, and bacteremic duration were not significantly different between the two groups. The 90-day SAB relapse was more common in the MRSA group than MSSA group (4.9% vs. 0.6%, P=0.04), while the 90-day mortality was comparable between the two groups (23.9% vs. 28.0%, P=0.39). 결론: In this study, a significant number of ST72 MSSA and ST72 MRSA infection occurred in hospital and healthcare settings. The 90-day recurrence rate was higher in methicillin-resistant ST72 infection than in methicillin-susceptible ST72 infection but there was no significant differences in type of main infection focus, presence of persistent bacteremia, and 90-day mortality. [ABSTRACT FROM AUTHOR]

배경: There are limited data comparing the transmission rates and kinetics of viable virus shedding of the omicron variant to those of the delta variant. We compared these rates in hospitalized patients infected with delta and omicron variants. 방법: We prospectively enrolled adult patients with COVID-19 admitted to a tertiary care hospital in South Korea between September 2021 and May 2022. Secondary attack rates were calculated by epidemiologic investigation, and daily saliva samples were collected to evaluate viral shedding kinetics. Genomic and subgenomic SARS-CoV-2 RNA was measured by PCR, and virus culture was performed from daily saliva samples. 결과: A total of 88 patients with COVID-19 who agreed to daily sampling and were interviewed, were included. Of the 88 patients, 48 (59%) were infected with delta, and 34 (41%) with omicron ; a further five patients gave undetectable or inconclusive RNA PCR results and one was suspected of being co-infected with both variants. The baseline characteristics of the two groups were comparable except that fewer of the delta patients had been vaccinated, and the delta patients had more severe disease. The latter also had a higher secondary attack rate (31% [38/124]) vs. 7% [34/456], p<0.001 : Table 1). Multivariable analysis revealed that moderate-to-critical disease severity (HR 1.96), immunocompromised status (HR 2.17), fully- or 1st booster-vaccinated status (HR 0.49), and omicron infection (HR 0.44) were independently associated with prolonged viable virus shedding (Table 2). 결론: Patients with omicron infections had higher transmission rates but shorter periods of transmissible virus shedding than those with delta infections. [ABSTRACT FROM AUTHOR]

Eosinophilic meningitis is defined as the presence of more than 10 eosinophils per µl in the cerebrospinal fluid (CSF), or eosinophils accounting for more than 10% of CSF leukocytes in patients with acute meningitis. Parasites are the most common cause of eosinophilic meningitis worldwide, but there is limited research on patients in Korea. Patients diagnosed with eosinophilic meningitis between January 2004 and June 2018 at a tertiary hospital in Seoul, Korea were retrospectively reviewed. The etiology and clinical characteristics of each patient were identified. Of the 22 patients included in the study, 11 (50%) had parasitic causes, of whom 8 (36%) were diagnosed as neurocysticercosis and 3 (14%) as Toxocara meningitis. Four (18%) patients were diagnosed with fungal meningitis, and underlying immunodeficiency was found in 2 of these patients. The etiology of another 4 (18%) patients was suspected to be tuberculosis, which is endemic in Korea. Viral and bacterial meningitis were relatively rare causes of eosinophilic meningitis, accounting for 2 (9%) and 1 (5%) patients, respectively. One patient with neurocysticercosis and 1 patient with fungal meningitis died, and 5 (23%) had neurologic sequelae. Parasite infections, especially neurocysticercosis and toxocariasis, were the most common cause of eosinophilic meningitis in Korean patients. Fungal meningitis, while relatively rare, is often aggressive and must be considered when searching for the cause of eosinophilic meningitis. [ABSTRACT FROM AUTHOR]

Background: Q fever endocarditis is a major cause of culture-negative endocarditis. The role of Coxellia burnetii is underestimated because it is difficult to diagnose. We investigated the significance of C. burnetii as the cause of culture-negative endocarditis and vascular infection by examining blood and tissue specimens using serological testing and polymerase chain reaction (PCR). Methods: All patients with infective endocarditis or large vessel vasculitis were prospectively enrolled at a tertiary-care hospital from May 2016 through September 2020. Q fever endocarditis and vascular infection were diagnosed based on: (1) positive PCR for a cardiac valve or vascular tissue, (2) positive PCR for blood or phase I immunoglobulin G (IgG) ≦ 6400, or (3) phase I IgG ≦ 800 and < 6400 with morphologic abnormality. PCR targeted C. burnetii transposase gene insertion element IS1111a. Results: Of the 163 patients, 40 (25%) had culture-negative endocarditis (n=35) or vascular infection (n=5). Of the 40 patients, 24 (60%) were enrolled. Eight (33%) were diagnosed with Q fever endocarditis or vascular infection. Of these 8 patients, 6 had suspected acute Q fever endocarditis or vascular infection with negative phase I IgG. Six patients were not treated for C. burnetii, 4 were stable after surgery. One patient died due to surgical site infection after 5months post-operatively and one died due to worsening underlying disease. Conclusions: Approximately one-third of patients with culture-negative endocarditis and vascular infection was diagnosed as Q fever. Q fever endocarditis and vascular infection may be underestimated in routine clinical practice in South Korea. [ABSTRACT FROM AUTHOR]

The prevalence of human taeniasis has decreased in Korea. The stool egg positive proportion decreased from 1.9% in 1971 to 0% in 2004 in nationwide surveys. The neurocysticercosis (NCC) is also presumed to decrease. However, detailed information regarding the recent status of NCC in Korea is lacking. We retrospectively reviewed NCC cases from 1990 to 2016 at Asan Medical Center, a 2700-bed tertiary referral hospital in Korea. We identified patients based on clinical symptoms, brain imaging, pathology and serological assay. The cases were classified as parenchymal, extraparenchymal, and mixed NCC. Eighty-one patients were included in the analysis. The mean age was 54.5 years, and 79.0% were male. The number of NCC cases was highest from 1995 to 1999, and continuously decreased thereafter. Forty (49.4%) patients had parenchymal NCC, while 25 (30.9%) patients had extraparenchymal NCC, and 16 (19.8%) patients had mixed NCC. The seizure and headache were most common symptom of parenchymal NCC and extraparenchymal NCC respectively. Hydrocephalus was more common in extraparenchymal NCC, and patients with extraparenchymal NCC were more likely to require a ventriculoperitoneal shunt. Cases of NCC are decreasing accordingly with human taeniasis and lesion location was the most important determinant of clinical presentation and outcome of NCC in Korea. [ABSTRACT FROM AUTHOR]

Background: Enterobacter species are important nosocomial pathogens, and there is growing concern about their ability to develop resistance during antimicrobial therapy. However, few data are available on the clinical characteristics and outcomes of Enterobacter spontaneous bacterial peritonitis (SBP).Methods: We retrospectively identified all patients with SBP caused by Enterobacter species admitted to a tertiary care hospital between January 1997 and December 2013. Each case was age- and sex-matched with four patients with Escherichia coli SBP.Results: A total of 32 cases with Enterobacter SBP and 128 controls with E. coli SBP were included. Twenty-one (65.6 %) cases and 111 (86.7 %) controls had Child-Pugh class C (P = 0.006). Cases were significantly more likely to have hepatocellular carcinoma (65.6 % vs. 37.5 %, P = 0.004) and upper gastrointestinal bleeding (28.1 % vs. 9.4 %, P = 0.005). The initial response to empirical therapy (81.3 % vs. 81.2 %, P = 0.995) and the 30-day mortality (37.5 % vs. 28.9 %, P = 0.35) were not significantly different between the groups. Drug resistance emerged in one case and in no controls (4.3 % [1/23] vs. 0 % [0/98], P = 0.19).Conclusions: Compared with E. coli SBP, patients with Enterobacter SBP more frequently had hepatocellular carcinoma and upper gastrointestinal bleeding, yet clinical outcomes were comparable. Development of resistance during third-generation cephalosporin therapy was infrequent in patients with Enterobacter SBP. [ABSTRACT FROM AUTHOR]

The article presents the revisions to the adult immunization recommendations outlined in the "Adult Immunization" book published by the Korean Society of Infectious Diseases (KSID). Topics covered include recommendations on pneumococcal vaccine for adults, recommendations on tetanus-diphtheria-pertussis (Tdap) vaccine for pregnant women or women who plan on pregnancy and recommendations on herpes zoster vaccine.

The author emphasizes the importance of meningococcal vaccination for the South Korean military. He applauds that decision to commence vaccination of all recruits with a quadrivalent meingococcal conjugate vaccine on December 11, 2012. He also discusses the reasons for the establishment of a preventive strategy, as well as the opposition of some physicians to the introduction of the meningococcal vaccination.

Cystic echinococcosis is a disease caused by tapeworm Echinococcus granulosus, which had been rarely reported in South Korea. We present the case of Korean patient with hepatic hydatid cyst, who had very long incubation period about 35 years. A 71-year-old male visited our hospital due to abnormal findings of his routine health screenings. He had examination with abdominal ultrasonography three months ago, that revealed a huge hepatic mass. Then, he was admitted to our hospital for further evaluation. At admission, he did not complain of abdominal discomfort and gastrointestinal symptoms such as nausea, vomiting. He was currently taking medications for hypertension and dyslipidemia. He was living in urban area of Busan, South Korea, and denied recent history of travel abroad or consumption of raw or undercooked meat. He did not show any tenderness or rebound tenderness over the right upper quadrant of his abdomen. The initial blood tests were in normal range. Outside CT scan showed the 17 centemeter-sized well defining mass in right lobe of liver with inner multiseptated cystic lesions. And there was no solid lesion or calcification in the hepatic mass. The mass had high signal intensity in T2 phase without diffusion restriction of MRI suggesting the high probability of hydatid cyst. Additional clue for the risk of echinococcosis was obtained from asking about his residence or visit to Middle East country. He stated that he had lived in a rural area in Iraq 35 years ago for working as constructor. He had casual contact with sheeps and dogs and frequently consumed lambs during staying in Iraq. For diagnostic confirmation, the test of Echinococcus immunoglobulin G was performed and result was positive. We diagnosed him as hepatic cystic echinococcosis, stage CE2 according to WHO classification. Surgical resection of the mass was planned with peri-operative anthelminthic treatment. Albendazole 400mg twice daily was administered for 20 days, followed by right lobectomy of liver. Histopathologic examination showed the well-demarcated unilocular cyst containing numerous endocysts. The protoscoleces of the Echinococcus granulosus was found in cystic fluid. He was discharged and planned to have albendazole maintenance treatment for 6 months. The asymptomatic incubation period of the disease can last many years because of helminthic slow growing. History taking should be thorough especially for patients having unproven route of Echinococcosis. [ABSTRACT FROM AUTHOR]

배경 Patients with legionella pneumonia occasionally experience initial clinical improvement but radiologic progression. However, there have been limited data on this issue. 방법 All patients who were diagnosed as legionella pneumonia were retrospectively enrolled from a tertiary hospital in South Korea between March 2011 and May 2020. Legionella pneumonia was defined as abnormal chest radiograph with at least one positive finding of the following tests: urinary antigen test, sputum legionella PCR, or sputum legionella culture. Clinical improvement was defined as defervescence and decreased CRP. Medical records were reviewed for the clinical and radiologic records at treatment day 7, 14, and at discharge, respectively. 결과 Of 140 patients with legionella pneumonia, 33 (24%) underwent initial clinical deterioration and the remaining 107 (76%) initial clinical improvement at day 7. Finally, the 107 patients who had initial clinical improvement were analyzed. Of these 107 patients, 22 (21%) experienced radiologic progression despite of clinical improvement. Risk factors for these patients with initial clinical improvement but radiologic progression were high pneumonia severity index (PSI) score and the use of mechanical ventilation. Mortality was not significantly different between those with initial clinical improvement but radiologic deterioration and those with both initial clinical and radiologic improvement (28% vs 12%, P=0.49). 결론 About one fifth of patients with legionella pneumonia, especially who had high PSI score and received mechanical ventilation, experienced radiologic deterioration despite of clinical improvement 1 week after appropriate treatment. Although we did not find a significantly worse outcome in these patients, further studies are needed in terms of the necessity of immunomodulating agents at early stage of disease. [ABSTRACT FROM AUTHOR]