Molecular epidemiology, resistance and virulence of Haemophilus influenzae in children with ocular infection
10.3760/cma.j.cn112309-20240729-00283
- VernacularTitle:儿童眼部感染流感嗜血杆菌的分子流行病学及耐药性和毒力研究
- Author:
Chunli LIN
1
;
Xiucai ZHANG
;
Yining ZHAO
;
Chao FANG
;
Shixing LIU
;
Jintao XIA
;
Mingming ZHOU
Author Information
1. 泉州市妇幼保健院·儿童医院检验科，泉州 362000
- Publication Type:Journal Article
- Keywords:
Haemophilus influenzae;
Whole-genome sequencing;
Molecular epidemiology;
Resistant genes;
Virulence factors
- From:
Chinese Journal of Microbiology and Immunology
2024;44(12):1084-1090
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the molecular epidemiology, drug resistance and virulence of Haemophilus influenzae in children with ocular infection. Methods:Haemophilus influenzae isolates were obtained from ocular specimens of children. Antimicrobial susceptibility testing was conducted using the disk diffusion method and E-test. Whole-genome sequencing was performed to determine serotype, multilocus sequence typing, drug resistance genes, and virulence factors. Results:All 13 Haemophilus influenzae strains isolated from ocular infection specimens in children were identified as non-typeable Haemophilus influenzae. A total of 11 sequence types were identified through multilocus sequence typing, with ST2838 representing a novel sequence type. Haemophilus influenzae were 100.0% (13/13) sensitive to ceftriaxone, meropenem, and levofloxacin. The resistance rates to ampicillin, cefuroxime, ampicillin/sulbactam, amoxicillin/clavulanic acid, chloramphenicol, and trimethoprim-sulfamethoxazole were 84.6% (11/13), 46.2% (6/13), 38.5% (5/13), 15.4% (2/13), 15.4% (2/13), and 46.2% (6/13). The non-susceptible rate to azithromycin was found to be 46.2% (6/13). Whole-genome sequencing revealed the presence of resistance genes blaTEM-1B (84.6%, 11/13), tet( B) (15.4%, 2/13), catA2 (15.4%, 2/13), msr(D) (30.8%, 4/13), mef( A) (46.2%, 6/13). Additionally, 71 virulence genes were detected across the 13 strains, comprising 7 genes associated with adherence, 12 genes related to nutritional and metabolic functions, and 52 genes involved in immune modulation. Conclusions:Haemophilus influenzae in pediatric patients with ocular infections exhibits a high rate of resistance to ampicillin, predominantly mediated by the blaTEM-1B. Clinical laboratories should pay attention to the detection of Haemophilus influenzae in ocular specimens and maintain ongoing surveillance of antimicrobial resistance patterns and virulence factors.
