Evolving molecular epidemiology and antimicrobial resistance of Streptococcus agalactiae in South Korea and East Asia: a narrative review
Review article Kwangjin Ahn , Young Uh Department of Laboratory Medicine, Wonju Severance Christian Hospital, Yonsei University Wonju College of Medicine, Wonju, Korea Ann Clin Microbiol 2026;29(3):12. https://doi.org/10.5145/ACM.2026.29.3.12Received on 24 June 2026, Revised on 20 July 2026, Accepted on 23 July 2026, Published on 16 September 2026.Copyright © Korean Society of Clinical Microbiology.This is an […]
Table 3. Proposed biological constraints associated with sustained β-lactam susceptibility in group A Streptococcus
Ann Clin Microbiol 2026;29(3):11. Molecular mechanisms, epidemiology, and clinical implications of macrolide resistance in group A Streptococcus: a narrative review Download table Mechanism Explanation Clinical significance Representative reference(first author, year) Lack of alterations in PBPs GAS rarely develops mutations in PBPs, the primary targets of β-lactam antibiotics, unlike Streptococcus pneumoniae Prevents emergence of intrinsic β-lactam resistance […]
Table 2. Representative associations between emm types and macrolide resistance determinants in group A Streptococcus
Ann Clin Microbiol 2026;29(3):11. Molecular mechanisms, epidemiology, and clinical implications of macrolide resistance in group A Streptococcus: a narrative review Download table emm type Geographic setting Reported resistance determinant(s) Typical phenotype Representative epidemiological association Representative reference(first author, year) emm4 Europe, North America mefA M phenotype emm4/ST39 lineage associated with mefA-mediated macrolide resistance Berbel, 2022 [5];Silva-Costa, 2015 […]
Table 1. Selected studies reporting macrolide resistance and molecular epidemiology of group A Streptococcus in different geographic settings
Ann Clin Microbiol 2026;29(3):11. Molecular mechanisms, epidemiology, and clinical implications of macrolide resistance in group A Streptococcus: a narrative review Download table Country/region Study period Population/infection type No. of isolates Susceptibility method/breakpoint Reported resistance/nonsusceptibility (%) Major resistance determinants/emm types Representative reference (first author, year) China (Beijing) 2016–2017 Children with scarlet fever; throat isolates 297 Disk diffusion; CLSI […]
Fig. 1. Two major mechanisms of macrolide resistance in group A Streptococcus: active drug efflux mediated by mef genes (left) and target-site modification mediated by erm genes through methylation of 23S rRNA within the 50S ribosomal subunit (right). MLSB, macrolide-lincosamide-streptogramin B resistance phenotype.
Ann Clin Microbiol 2026;29(3):11. Molecular mechanisms, epidemiology, and clinical implications of macrolide resistance in group A Streptococcus: a narrative review Download image
Molecular mechanisms, epidemiology, and clinical implications of macrolide resistance in group A Streptococcus: a narrative review
Review article Sunjoo Kim Department of Laboratory Medicine, GC Labs, Yangsan, Korea Ann Clin Microbiol 2026;29(3):11. https://doi.org/10.5145/ACM.2026.29.3.11Received on 08 June 2026, Revised on 21 July 2026, Accepted on 23 July 2026, Published on 14 September 2026.Copyright © Korean Society of Clinical Microbiology.This is an Open Access article which is freely available under the Creative Commons […]
Fig. 1. Practical molecular diagnostic algorithm for macrolide-resistant Mycoplasma pneumoniae in the routine clinical microbiology laboratory. PCR, polymerase chain reaction.
Ann Clin Microbiol 2025;29(3):10. Macrolide-resistant Mycoplasma pneumoniae: laboratory diagnosis and epidemiology Download image
Table 1. Trend of macrolide-resistant Mycoplasma pneumoniae prevalence and dominant sequence types in Korea
Ann Clin Microbiol 2025;29(3):10. Macrolide-resistant Mycoplasma pneumoniae: laboratory diagnosis and epidemiology Download table Period Sample (n) MRMP prevalence (%) Dominant ST / clone Notes Reference 2000–2011(longitudinal) 2,089 specimens / 255 MP+ / 80 with mutation 2.9 (2003) → 62.9 (2011) Not typed National longitudinal trend [10] 2010(Oct–Nov) 195 / 17 MP+ 17.6 (3/17, A2063G) Not typed […]
Macrolide-resistant Mycoplasma pneumoniae: laboratory diagnosis and epidemiology
Review Kuenyoul Park1 , Heungsup Sung2 1Department of Laboratory Medicine, Hanyang University Seoul Hospital, Hanyang University College of Medicine, Seoul, Korea2Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea Correspondence to Heungsup Sung E-mail: sung@amc.seoul.kr Ann Clin Microbiol 2026;29(3):10. https://doi.org/10.5145/ACM.2026.29.3.10Received on 28 April 2026, Revised on 21 May 2026, […]
Fig. 2. Performance of the two-stage laser scattering signal amplification (LSSA) deep-learning classifier on hold-out reference-strain and preliminary clinical specimens. (A) Confusion matrix for Model 1, a three-class classifier (Negative, <10³ colony-forming units [CFU] /mL; Positive—C. albicans, ≥10⁴ CFU/mL; Positive—Non-albicans, ≥10⁴ CFU/mL), evaluated on the 25% hold-out test partition of the Model 1 reference-strain dataset (n = 80 vials; reference strains: C. albicans ATCC 14053, N. glabratus KCTC 7219, C. tropicalis KCTC 7212, C. parapsilosis ATCC 22019, P. kudriavzevii ATCC 6258). Rows indicate culture-confirmed true class; columns indicate model prediction. Overall accuracy: 73.8% (95% confidence interval [CI] 62.7–83.0%). (B) Confusion matrix for Model 2, a binary classifier (C. albicans vs. C. tropicalis), evaluated in a cascade manner on reference-strain samples predicted as Positive by Model 1 (n = 36; cascade evaluation). Overall accuracy: 77.8% (95% CI 60.8–89.9%). (C) Confusion matrix for the preliminary clinical evaluation, comparing patient-level LSSA prediction against the Candida culture result for 20 vaginal discharge specimens (5 Candida culture-positive, 15 Candida culture-negative). Absolute counts are printed inside each cell. Cell shading intensity is proportional to the cell count within each sub-panel. All 95% CIs were calculated by the exact ClopperPearson binomial method.
Ann Clin Microbiol 2025;29(2):9. Laser scattering signal amplification and deep learning for detection of Candida culture positivity in women with vaginal symptoms: a preliminary analytical and pilot clinical evaluation Download image