Moraxella Keratitis: Analysis of Risk Factors, Clinical Characteristics, Management, and Treatment Outcomes

To analyze the risk factors, clinical characteristics, management, and treatment outcomes of culture-proven cases of Moraxella keratitis at our center.

Retrospective observational case series.

Thirty-nine culture-proven cases of Moraxella keratitis (39 eyes) diagnosed and treated between January 2003 and April 2018 at the University of Pittsburgh Medical Center were identified and retrospectively reviewed for ocular and systemic risk factors, treatment modalities, and outcomes, as well as for antimicrobial sensitivity and resistance data.

The mean age of the 39 patients was 63.0 (range 4-95 years) with median follow-up time of 170 days. Thirty-four of 39 patients (87.2%) had an ocular risk factor, the most common of which were blepharitis in 12 (30.8%), dry eyes in 12 (30.8%), and history of ocular surgery in 9 (23.1%). History of diabetes mellitus was found in 8 patients (20.5%). Thirty-six of 39 patients (92.3%) received a fluoroquinolone (92.3%) and 30 of 39 (76.7%) received topical fortified antibiotics. Resistance to fluoroquinolones, gentamicin, and tobramycin was seen in 1 patient each, respectively. Four patients (10.3%) required tarsorrhaphy, 6 patients (15.4%) required penetrating keratoplasty, and 1 patient required enucleation. Of the 35 patients for whom visual acuity information was available, 19 (54.3%) were count fingers or worse at most recent follow-up.

Ocular risk factors, especially poor ocular surface, were identified in the vast majority of patients with Moraxella keratitis. Moraxella isolates in our study were susceptible to fluoroquinolones and aminoglycosides. Many patients required surgical intervention and the final visual acuity was often poor.