0
We're unable to sign you in at this time. Please try again in a few minutes.
Retry
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
Retry
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
Brief Report |

Novel Phagocytosis-Resistant Extended-Spectrum β-Lactamase–Producing Escherichia coli From Keratitis ONLINE FIRST

Daria Van Tyne, PhD1,2; Joseph B. Ciolino, MD1; Jay Wang, MD1; Marlene L. Durand, MD1,3,4; Michael S. Gilmore, PhD1,2
[+] Author Affiliations
1Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts
2Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts
3Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts
4Infectious Disease Service, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
JAMA Ophthalmol. Published online September 15, 2016. doi:10.1001/jamaophthalmol.2016.3283
Text Size: A A A
Published online

Importance  Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli are highly antibiotic resistant, and primary ocular infection by ESBL E coli has rarely been reported. A novel mutation conferring phagocytosis resistance would position a strain well to infect the cornea.

Observations  A woman with recurrent keratitis presented with a corneal ulcer, which was culture positive for ESBL E coli. Resistant to nearly all other antimicrobials, the infection was treated with amikacin and polymyxin B–trimethoprim, and the ulcer resolved over 3 weeks. Analysis of the E coli genome showed it to belong to multilocus sequence type 131 (ST131). This isolate was found to possess a novel deletion in yrfF, an essential regulator of bacterial capsule synthesis. Disruption of yrfF, which confers mucoidy and increased virulence, has not been previously observed in ESBL E coli from any infection site. This novel variant was experimentally proven to cause the mucoid phenotype, and corresponding resistance to phagocytic killing.

Conclusions and Relevance  Increased resistance to immune clearance in an ESBL E coli lineage already known for its virulence is an unsettling development. This phenotype, which likely positioned it as an unusual cause of corneal ulcer, can be easily recognized in the laboratory, which should help limit its spread.

Figures in this Article

Figures

Place holder to copy figure label and caption
Figure.
Virulence Phenotypes of MEEI01

A, Wild-type MEEI01, B, yrfF-complemented MEEI01, and C, empty vector–containing MEEI01 streaked on brain heart infusion agar containing 5% sucrose and 0.08% Congo red. D, Phagocytosis of each strain by RAW264.7 murine macrophages. Error bars indicate standard error of the mean.

Graphic Jump Location

Tables

References

Correspondence

CME
Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.

Multimedia

Some tools below are only available to our subscribers or users with an online account.

65 Views
0 Citations
×

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

Related Content

Customize your page view by dragging & repositioning the boxes below.

Articles Related By Topic
Related Collections
Jobs
brightcove.createExperiences();