Tags

Type your tag names separated by a space and hit enter

Antimicrobial resistance among Shigella in New Zealand.
N Z Med J 2018; 131(1477):56-62NZ

Abstract

AIM

We undertook a national survey to provide current information on antimicrobial resistance among Shigella isolated in New Zealand.

METHODS

Diagnostic laboratories are requested to refer all Shigella isolates to the Institute of Environmental Science and Research (ESR) for epidemiological typing as part of the national surveillance of shigellosis. The antimicrobial susceptibility of 263 non-duplicate Shigella isolates referred to ESR in 2015 and 2016 was tested.

RESULTS

The 263 Shigella comprised 141 (53.6%) S. sonnei, 113 (43.0%) S. flexneri, 7 (2.7%) S. boydii and 2 (0.8%) S. dysenteriae. Among the 141 S. sonnei, the majority were either biotype g (90) or biotype a (50). Rates of resistance to the two currently recommended first-line antibiotics, co-trimoxazole and fluoroquinolones, were relatively high at 56.7% and 22.8%, respectively. Azithromycin is considered a second-line treatment option, but 11.0% of Shigella were categorised as having a non-wildtype (NWT) azithromycin phenotype (ie, having some mechanism of azithromycin resistance although not necessarily clinically resistant). There were several significant differences in resistance between the two most prevalent S. sonnei biotypes, with resistance being significantly more prevalent among biotype g isolates. Shigella from patients who had not travelled overseas were significantly more likely to be azithromycin NWT than isolates from patients who had recently travelled (20.7 vs 5.6%). Azithromycin NWT was more prevalent among Shigella from males than females (13.9 vs 7.7%).

CONCLUSIONS

These results suggest there is an immediate need to revise the currently recommended first-line treatment for shigellosis, especially when treatment is given on an empirical basis. Equally concerning is the fact that resistance to the second-line antibiotic for shigellosis, azithromycin, appears to be emerging in New Zealand. As diagnostic laboratories increase their use of culture-independent testing, it is recommended that they should continue to culture specimens from all shigellosis cases so that isolates are available for susceptibility testing and epidemiological typing.

Authors+Show Affiliations

Scientist, Antimicrobial Reference Laboratory, Institute of Environmental Science and Research, Wellington.Technician, Antimicrobial Reference Laboratory, Institute of Environmental Science and Research, Wellington.(previously) Clinical Microbiologist, Institute of Environmental Science and Research, Wellington.Public Health Physician, Health Intelligence Team, Institute of Environmental Science and Research, Wellington.

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

29927916

Citation

Heffernan, Helen, et al. "Antimicrobial Resistance Among Shigella in New Zealand." The New Zealand Medical Journal, vol. 131, no. 1477, 2018, pp. 56-62.
Heffernan H, Woodhouse R, Hewison C, et al. Antimicrobial resistance among Shigella in New Zealand. N Z Med J. 2018;131(1477):56-62.
Heffernan, H., Woodhouse, R., Hewison, C., & Sherwood, J. (2018). Antimicrobial resistance among Shigella in New Zealand. The New Zealand Medical Journal, 131(1477), pp. 56-62.
Heffernan H, et al. Antimicrobial Resistance Among Shigella in New Zealand. N Z Med J. 2018 06 22;131(1477):56-62. PubMed PMID: 29927916.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Antimicrobial resistance among Shigella in New Zealand. AU - Heffernan,Helen, AU - Woodhouse,Rosemary, AU - Hewison,Chris, AU - Sherwood,Jillian, Y1 - 2018/06/22/ PY - 2018/6/22/entrez PY - 2018/6/22/pubmed PY - 2018/6/22/medline SP - 56 EP - 62 JF - The New Zealand medical journal JO - N. Z. Med. J. VL - 131 IS - 1477 N2 - AIM: We undertook a national survey to provide current information on antimicrobial resistance among Shigella isolated in New Zealand. METHODS: Diagnostic laboratories are requested to refer all Shigella isolates to the Institute of Environmental Science and Research (ESR) for epidemiological typing as part of the national surveillance of shigellosis. The antimicrobial susceptibility of 263 non-duplicate Shigella isolates referred to ESR in 2015 and 2016 was tested. RESULTS: The 263 Shigella comprised 141 (53.6%) S. sonnei, 113 (43.0%) S. flexneri, 7 (2.7%) S. boydii and 2 (0.8%) S. dysenteriae. Among the 141 S. sonnei, the majority were either biotype g (90) or biotype a (50). Rates of resistance to the two currently recommended first-line antibiotics, co-trimoxazole and fluoroquinolones, were relatively high at 56.7% and 22.8%, respectively. Azithromycin is considered a second-line treatment option, but 11.0% of Shigella were categorised as having a non-wildtype (NWT) azithromycin phenotype (ie, having some mechanism of azithromycin resistance although not necessarily clinically resistant). There were several significant differences in resistance between the two most prevalent S. sonnei biotypes, with resistance being significantly more prevalent among biotype g isolates. Shigella from patients who had not travelled overseas were significantly more likely to be azithromycin NWT than isolates from patients who had recently travelled (20.7 vs 5.6%). Azithromycin NWT was more prevalent among Shigella from males than females (13.9 vs 7.7%). CONCLUSIONS: These results suggest there is an immediate need to revise the currently recommended first-line treatment for shigellosis, especially when treatment is given on an empirical basis. Equally concerning is the fact that resistance to the second-line antibiotic for shigellosis, azithromycin, appears to be emerging in New Zealand. As diagnostic laboratories increase their use of culture-independent testing, it is recommended that they should continue to culture specimens from all shigellosis cases so that isolates are available for susceptibility testing and epidemiological typing. SN - 1175-8716 UR - https://www.unboundmedicine.com/medline/citation/29927916/Antimicrobial_resistance_among_Shigella_in_New_Zealand_ L2 - https://medlineplus.gov/antibioticresistance.html DB - PRIME DP - Unbound Medicine ER -