Annals of Clinical Microbiology, The official Journal of the Korean Society of Clinical Microbiology

6

Weeks in Review

2

Weeks to Publication
Indexed in KCI, KoreaMed, Synapse, DOAJ
Open Access, Peer Reviewed
pISSN 2288-0585 eISSN 2288-6850

March, 2023. Vol. 26 No. 1.

Review article

Syndromic testing for sexually transmitted infection: current and future demand

In Young Yoo

Ann Clin Microbiol 2023 March, 26(1): 1-9. Published on 20 March 2023.

Sexually transmitted infections (STIs) are a major global public health problem, with significant social burden worldwide. Accurate and appropriate diagnosis and treatment of STIs are important for preventing the transmission of STIs as well as major health consequences of untreated STIs, such as infertility and certain cancer. For diagnosis of STIs, the application of conventional culture and immunoassays is limited by their low sensitivity and long turnaround time. Nucleic acid amplification tests for STIs allow for syndromic tests for multiple pathogens simultaneously and show high sensitivity with a short turnaround time. In this review, we discuss the characteristics of commercially available multiplex molecular platforms and the features needed in next-generation syndromic tests for STIs.

[in Korean]

Original article

Epidemiology and subtype distribution of Blastocystis among asymptomatic volunteers in Korea: a multicenter study

Seong Hoon Kim, Jung-Hyun Byun, YeJin Oh, Changseung Liu, Mi Hyun Bae, Eun Jeong Won

Ann Clin Microbiol 2023 March, 26(1): 11-17. Published on 20 March 2023.

Background: Blastocystis is a genus of intestinal, anaerobic protozoan parasites that can be isolated from humans, animals, and the environment. We aimed to determine the distribution of Blastocystis and subtypes (STs) using stool samples obtained from healthy volunteers at collection centers in Korea.

Methods: A total of 478 stool samples from volunteers were collected at five collection centers throughout Korea. The presence of Blastocystis was determined using PCR based on the small subunit (SSU) rRNA gene, and Blastocystis STs were confirmed through sequencing of the SSU rRNA gene.

Results: Molecular analysis revealed the presence of Blastocystis in 27 (5.6%) of the enrolled participants. Two STs were identified: ST3 (66.7%) and ST1 (33.3%). The positive rates of Blastocystis varied by geographical region, ranging from 1.2%–12.0%. ST3 was the predominant subtype in all centers except one, where only ST1 was isolated. Phylogenic analysis showed clustering based on ST, but no significant differences were found among the regions. There was no association between Blastocystis colonization and either age or sex of the participants.

Conclusions: The results of this multicenter study demonstrated colonization by Blastocystis, mainly ST3, in the gastrointestinal tracts of asymptomatic individuals in Korea.

Original article

Evaluation of two commercial kits for rapid pathogen identification directly from positive blood cultures by matrix-associated laser desorption/ionization time-of-flight mass spectrometry

Sung Gyun Park, Do-Hoon Kim

Ann Clin Microbiol 2023 March, 26(1): 19-27. Published on 20 March 2023.

Background: A bloodstream infection is a life-threatening medical emergency, with a mortality rate of up to 30%. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) can be used to identify pathogens directly from positive blood cultures. Two commercial preparation kits, SepsiTyper (Bruker Daltonics, Germany) and SepsiPrep (ASTA Corp., Korea), and two MALDI-TOF MS systems, MALDI Biotyper Sirius (Bruker Daltonics, Germany) and VITEK MS PRIME (bioMérieux, France), are available in Korea. We examined these kits and MALDI-TOF MS systems to analyze their performance.

Methods: We assessed the effectiveness of direct identification using 47 blood cultures and 3 bile cultures positive for microbial growth. The VIRTUO system (bioMérieux, France) was used to incubate the samples after they were collected in Bact/ALERT aerobic and anaerobic bottles. The manufacturers’ protocols were followed for both the SepsiTyper and SepsiPrep kits.

Results: The SepsiTyper yielded considerably more accurate identifications than did the SepsiPrep, when utilized in MALDI-TOF MS systems (P = 0.0044). However, the SepsiPrep was easier to use and the results more quickly obtained than with the SepsiTyper. The MALDI Biotyper Sirius produced more accurate identifications with the SepsiTyper than did the VITEK MS PRIME (P = 0.0736). The SepsiTyper enabled the accurate identification of five of six polymicrobial cases, utilizing either the MALDI-TOF MS systems.

Conclusions: Among the pathogen ID kits tested in this study, the SepsiTyper with MALDI Biotyper Sirius performed the best. In clinical laboratories utilizing VITEK MS PRIME, it is recommended that the either the SepsiTyper or SepsiPrep kit be used for direct identification, while considering certain limitations in terms of performance.