ESCRS - PP17.02 - Title: Is Moraxella Non-Liquefaciens Induced Microbial Keratitis Related To Mask Wearing?

Title: Is Moraxella Non-Liquefaciens Induced Microbial Keratitis Related To Mask Wearing?

Published 2022 - 40th Congress of the ESCRS

Reference: PP17.02 | Type: Case report | DOI: 10.82333/3e8g-1518

Authors: Samuel Yee War Leung* 1 , Thomas Jenyon 2

1Foundation Year Rotational Ophthalmology,The Shrewsbury and Telford NHS Trust,Shrewsbury,United Kingdom, 2Consultant Opthalmologist,The Shrewsbury and Telford NHS Trust,Shrewsbury,United Kingdom

We describe a case of Moraxella Non-Liquefaciens keratitis in a non-contact lens wearer amongst 4 separate cases over a 6 month period. Each case was identified as unique to the individual. 

Moraxella Non-Liquefaciens is a commensal found in the upper respiratory tract, normally non-pathogenic, and rarely causes microbial keratitis. It may not respond to usual first line antimicrobials. The visual prognosis of Moraxella Non-Liquefaciens keraitis is very poor and slow to respond to antimicrobial therapy. 

We postulate that Moraxella Non-Liquefaciens keratitis may be the direct result of mask wearing due to the exhaled jet of air bringing upper respiratory commensal bacteria into contact with the ocular surface.

The cases were presented to and managed in a NHS District General hospital in England, serving around 500,000 population of predominantly Caucasian background.  

A 69-year-old female presented with hand movements vision secondary to significant central corneal ulcer with hypopyon. Corneal scrapes were sent to the microbiology department for culture and sensitivity screening and intensive topical antibiotics were commenced. Initially Cefuroxime 5% eyedrops and Exocin (ofloxacin) 0.3% eyedrops were used hourly.   

The ulcer failed to respond to initial therapy and continued to increase in size with some central thinning. Culture identified a unique Moraxella Non-Liquefaciens species sensitive to Gentamicin and Chloramphenicol. Antimicrobial therapy was switched to Gentamicin 1.5% eye drops hourly alongside Chloramphenicol eye ointment 1% at night and oral Doxycycline 100mg tablets twice a day for 2 weeks. Ascorbic Acid 2g tablets once a day was added to aid healing of the corneal tissue. 

Antibiotics were reduced and preservative free steroids added due to signficant ocular inflammation. Gentamicin was substituted with preservative free Chloramphenicol eye drops to aid healing. However progress was slow and epitheliasation took sixty-two days in total. Visual acuity at last visit was 6/18.

 

  1. Moraxella Non-Liquefaciens is a commensal in the upper respiratory tract and is a rare cause of keratitis.
  2. Our experiences with Moraxella Non-Liquefaciens keratitis and previous case series suggest a prolonged time until epithelisation and poor visual outcomes.
  3. We hypothesise redirected exhaled air secondary to mask wearing as a possible route of infection.
  4. With mask usage becoming more widespread, a possibility exists of increasing incidence of infections that are usually non-pathogenic, particularly microbes found in the upper respiratory tract and disseminated with exhaled air.
  5. Clinicians should be aware of Morexella species as a causative agent in microbial keratitis and may not respond to usual first line antimicrobials.