Moraxella species: infectious microbes identified by use of time-of-flight mass spectrometry
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To report the clinical manifestations, identification, antimicrobial susceptibilities, and treatment outcomes of ocular infections caused by Moraxella species.
Patients and methods
The medical records of all patients treated at the Departments of Ophthalmology of the Ogaki Municipal Hospital and the Gifu University Graduate School of Medicine for ocular infections caused by Moraxella species between January 2011 and June 2017 were examined. The stored Moraxella species isolated from ocular samples were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), molecular identification, and the biochemical properties.
Sixteen eyes of 16 patients were treated for Moraxella ocular infections. The patients’ median age was 72 years. A predisposing systemic or ocular condition was identified in 15 of the patients. Nine of the patients developed keratitis; four, conjunctivitis; and three, blebitis. M lacunata (6 eyes), M catarrhalis (6), M nonliquefaciens (3), and M osloensis (1) were identified by MALDI-TOF MS. All isolates were sensitive to levofloxacin, tobramycin, ceftazidime, ceftriaxone, and cefazolin. Twelve patients with keratitis or blebitis were treated with various topical antimicrobial combinations, and systemic antibiotics were used in 10 of the 12 patients. The mean time for the complete closure of the epithelial defects with keratitis was 24 days. The visual outcomes after treatment were favorable except in 1 keratitis patient who underwent enucleation.
The use of duo-therapy with a combination of fluoroquinolone and cefmenoxime should be considered in cases nonresponsive to monotherapy, such as keratitis and bleb-associated infections. MALDI-TOF MS is useful for the identification of Moraxella to the species level.
KeywordsMatrix-assisted laser desorption/ionization time-of-flight mass spectrometry Moraxella species Ocular infection
We would like to express our gratitude to Mr Haruki Sawamura, PhD, for scientific advice.
Conflicts of interest
S. Takahashi, None; K. Murata, None; K. Ozawa, None; H. Yamada, None; H. Kawakami, None; A. Nakayama, None; Y. Asano, None; K. Mochizuki, None; H. Mikamo, None.
- 17.National Surveillance of Infectious Keratitis in Japan. National Surveillance of Infectious Keratitis in Japan: current status of isolates, patient background, and treatment. Nippon Ganka Gakkai Zasshi. 2006;110:961–72 (in Japanese).Google Scholar
- 21.Morax V. Note sur un diplobacille pathogène pour la conjonctivite humaine. Ann Inst Pasteur. 1896;10:337–45.Google Scholar
- 22.Axenfeld T. Über die chronische Diplobacille conjunctivitis. Zentralbl Bakteriol. 1897;21:1–9.Google Scholar
- 32.Hori N, Mochizuki K, Ishida K, Yamamoto T, Mikamo H. Clinical characteristics and risk factors of glaucoma filtering bleb infections. Nippon Ganka Gakkai Zasshi. 2009;113:951–63 (in Japanese).Google Scholar
- 33.Nihonyanagi S, Wada T, Adachi Y, Fujimura H, Munekata S, Kanoh Y, et al. Trends in the occurrence and antibiotic susceptibility of Moraxella catarrhalis from 2009 to 2014. Jpn J Med Technol. 2016;65:268–74.Google Scholar
- 36.Hansen W, Butzler JP, Fuglesang JE, Henriksen SD. Isolation of penicillin and streptomycin resistant strains of Moraxella osloensis. Acta Pathol Microbiol Scand B Microbiol Immunol. 1974;82:318–22.Google Scholar