Ocular Adnexal Infections

The lacrimal gland and the nasolacrimal excretory system (canaliculus, nasolacrimal sac, and nasolacrimal duct), the extraocular muscles, the eyelids, eyelashes, eyebrows, and the conjunctiva comprise the ocular adnexal structures. Infections affecting these tissues represent a major cause of annual ophthalmology visits, a significant cause of morbidity, and healthcare cost. The purpose of this report is to critically review and evaluate the literature published over the past year pertaining to ocular adnexal infections. However, an update on microbial resistance precedes any discussion of infectious diseases. Sotonzono et al. reported cases of methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA, MRSA, respectively) refractory to fluoroquinolone therapy may be treated with 1 % vancomycin ointment [1]. The staphylococcal ocular adnexal infections included conjunctivitis, blepharitis, meibomitis, dacryocystitis, or keratitis. However, the study was small (25 patients) and adverse reactions to the vancomycin ointment occurred in 28 % of patients (7/28) and included eyelid edema and conjunctival hyperemia. Nonetheless, the importance of new antibiotics and formulations becomes clear, when one considers the emergence of antibiotic-resistant microorganisms and our obligation to prescribe antibiotic therapy responsibly. Another study examined culture and sensitivity results obtained from ocular and ocular adnexal infections over a 4-year period in order to trend the emergence of levofloxacin resistance [2]. These infections ranged from orbital cellulitis, blepharitis, dacryoadenitis, conjunctivitis, infectious corneal ulcer, and endophthalmitis, and of the 242 cases reviewed, levofloxacin-resistant strains occurred in 32.8 % of isolates. These data raise awareness of resistance to this fluoroquinolone and a possible future increase in levofloxacin-resistant ocular and ocular adnexal infections. Although no cases of vancomycin-resistant strains were reported, the authors advocate using this antibiotic only, when absolutely necessary to prevent the emergence of vancomycin resistance. Several antibiotic trials for the treatment of conjunctivitis were published over the past year. Malamos et al. showed single-dose oral azithromycin to be an effective alternative to combined oral azithromycin/doxycycline therapy in the treatment of adult inclusion conjunctivitis [3]. Topical azithromycin 1.5 % ophthalmic solution was shown to provide a more rapid resolution than tobramycin 0.3 % ophthalmic solution in the treatment of purulent bacterial conjunctivitis in children, with a more convenient twice-a-day dosing regimen [4]. A randomized control trial comparing polymyxin B-trimethoprim to moxifloxacin showed equal response rates in purulent conjunctivitis in pediatric patients and offered significant cost saving compared to moxifloxacin [5]. Finally, besifloxacin 0.6 % ophthalmic solution three times daily for 7 days was shown to be safe in patients aged 1 year and older for bacterial conjunctivitis [6, 7]. Conjunctivitis is arguably the most common ocular adnexal infection, and it is often difficult to determine the etiology due to the vast number of causes of this condition. Bennett et al. reported a multiplex real-time PCR assay for B. R. Costin J. D. Perry (&) Cole Eye Institute, Cleveland Clinic, 9500 Euclid Avenue, Mail Code i-20, Cleveland, OH 44195, USA e-mail: perryj1@ccf.org