Bo Hyun Kim, Tae-Hyoung Kim, Mi-Kyung Lee
Ann Clin Microbiol 2016 June, 19(2): 33-38. Published on 20 June 2016.
Background: Acute viral gastroenteritis is a common illness in young children. Rotavirus, norovirus and enteric adenovirus are the major agents for viral gastroenteritis. Their detection rates have gradually increased in Korea. Our aim was to monitor the epidemiologic characteristics of the aforementioned viruses and to determine the laboratory and clinical characteristics of pediatric patients infected with these viruses.
Methods: From December 2009 to November 2010, 685 stool specimens from patients hospitalized at Chung-Ang University Hospital were tested for the aforementioned viruses using multiplex PCR. A corresponding medical record review was retrospectively conducted.
Results: The overall prevalence rate was 44.8%, with rates of 16.3%, 1.9%, 22.7%, 3.1%, and 0.8% for rotavirus, norovirus genogroup I, norovirus genogroup II, enteric adenovirus, and astrovirus, respectively. Mixed virus infections were detected in 37 patients (5.4%). The highest incidence rates occurred in March 2010 (18.9%), in the 13-24 month age group (38.1%), and in males (53.1%). Fever and chills were most frequently observed in patients with adenovirus (44.4%) than other viruses, while diarrhea was most frequently observed in patients with rotavirus (93.7%). Leukocytosis (55.0%) and lymphocytosis (21.0%) were more common in the norovirus-infected group than other viruses-infected group.
Conclusion: Our results show different prevalence rates and clinical findings for each gastroenteritis-associated virus. To better understand the clinico-epidemiological features observed in this study, further epidemiologic and clinical investigations are needed.
Bo Hyun Kim, Tae-Hyoung Kim, Mi-Kyung Lee
Ann Clin Microbiol 2016 June, 19(2): 39-47. Published on 20 June 2016.
Background: Carbapenemase-producing Enterobacteriaceae (CPE) has been increasingly reported worldwide in the past 10 years, which is an important infection control concern. Since the epidemiology and characteristics of these CPEs vary according to institutes, we aimed to characterize CPEs in a university hospital during the recent 4 years.
Methods: From October 2011 to September 2015, CPE isolates from clinical specimens and hospital surveillance cultures were collected. Carbapenem resistance was confirmed by disk diffusion method and Minimal Inhibitory Concentration (MIC) was determined by agar dilution method. Carbapenemase production was tested by double disk test using aminophenylboronic acid and dipicolic acid. PCR and sequence analysis were performed to detect blaKPC, blaIMP-1, blaVIM-2, blaNDM-1-like genes and blaOXA-48 gene. Pulsed-field gel electrophoresis (PFGE) and Multilocus sequence typing (MLST) were conducted for KPC- producing Klebsiella pneumoniae isolates.
Results: Twenty-five isolates (11%) of CPE were identified among 222 carbapenem-resistant Enterobacteriacae isolates during the study period. The most prevalent CPE was KPC-producing K. pneumonia and others were IMP-1, VIM-2, NDM-1 type and OXA-48 producing CPEs. Most of these CPEs showed resistance to carbapenems with variable MICs. The sequence types (STs) of KPC-producing K. pneumoniae were ST307 and ST11. The PFGE of ST11 and ST307 showed clonality in each group suggesting the possibility of in-hospital outbreak.
Conclusion: The prevalence of CPE has been increasing. In our institute, KPC-producing K. pneumoniae was the most frequently isolated CPE in the recent 4 years. CPE including KPC producers can easily transfer their resistance. Therefore continuous monitoring and more intensified infection control for CPE should be considered.
[in Korean]
Si Hyun Kim, Sae Am Song, Jongyoun Yi, Duyeal Song, Chulhun Ludgerus Chang, Dong-Chul Park, Sang-Hwa Urm, Hye Ran Kim, Jeong Hwan Shin
Ann Clin Microbiol 2016 June, 19(2): 48-53. Published on 20 June 2016.
Background: Streptococcus pneumoniae is the most common human pathogen causing community-acquired pneumonia. There is little information on the recent antimicrobial susceptibility patterns of S. pneumoniae in Busan and Gyeongnam of Korea. The aim of this study was to investigate the distribution and antimicrobial resistance of S. pneumoniae at 4 university hospitals in Busan and Gyeongnam.
Methods: We collected and analyzed the antimicrobial susceptibility results of 850 S. pneumoniae strains isolated from regional 4 university hospitals during the last 2 years from July 2013 through June 2015.
Results: Among 850 S. pneumoniae strains, 635 strains were isolated from respiratory specimens, followed by blood (N=121), CSF (N=13), and others (N=81). Antimicrobial susceptibility rates to penicillin, cefotaxime and ceftriaxone were 79.4%, 76.6% and 83.6%, respectively. The resistant rates to erythromycin and clindamycin were 80.9% and 68.2%, respectively. The resistant rates to levofloxacin were 9.2%. There were some differences in resistant rates by age groups, years, and specimen types.
Conclusion: We found the changes of antimicrobial resistance of S. pneumoniae during the last 2 years. It is necessary to monitor the antimicrobial susceptibility of S. pneumoniae regularly for empirical therapy and for early detection of the changes of resistance.
[in Korean]
Jihye Ha, Yu Jin Park, Yee Jeong Kim, Hyun Cheol Oh, Young Ah Kim
Ann Clin Microbiol 2016 June, 19(2): 54-57. Published on 20 June 2016.
Bacillus cereus is a widespread organism in nature and a member of the B. cereus group of catalase- positive, aerobic, spore-forming, Gram-positive bacilli. B. cereus found in blood is often dismissed as a contaminant in the absence of repeated isolation from multiple cultures. Soft tissue and bone infection due to B. cereus have been associated with trauma, intravenous drug use, and an immunocompromised state. We report a very late prosthetic joint infection of the hip joint and consequent bacteremia caused by B. cereus, which occurred 13 years after total hip replacement surgery in the absence of recent trauma or intervention.