Transconjunctival orbital invasion by methicillin-resistant Staphylococcus aureus.

Report of a Case. A healthy 31-year-old man was referred for nonresolving conjunctivitis in the right eye. One week earlier, he developed redness and swelling of the right lower eyelid with conjunctival injection. After 4 days, he was evaluated in a local emergency department and began receiving cephalexin and gatifloxacin (Zymar) 4 times daily. The eyelid swelling partially resolved but the eye remained red, and the patient developed heavy yellow mucopurulent discharge that repeatedly accumulated in the medial canthus. He denied diplopia or epiphora. He was afebrile and felt well otherwise. He had no risk factors for immunosuppression or colonization with antibiotic-resistant bacteria. Visual acuity without correction was 20/25 OU. Ocular motility was normal. The left eye and adnexa were normal. The right lower eyelid showed minimal edema and mild redness, which was worse nasally (Figure, A). There was 3 large vessel bulbar conjunctival injection that was greater nasally. The inferior palpebral conjunctiva was intensely inflamed and had 2 areas of ulceration down to the tarsus (Figure, B). A narrow tract of deep tissue necrosis with a blind end originated inferior to the caruncle; it probed inferonasally to a depth of approximately 7 mm. The anterior segment was otherwise normal. An orbital computed tomographic scan showed preseptal and postseptal edema with inflammatory changes in the nasal extraconal fat, without discrete abscess. Culture of the drainage grew MRSA susceptible to vancomycin hydrochloride, rifampin, and clindamycin phosphate but resistant to penicillin and cefazolin sodium. The patient was treated for 7 days with intravenous vancomycin and tobramycin sulfate as well as oral rifampin and then for 7 days with oral trimethoprim sulfa double strength with clinical resolution. Nasal cultures for MRSA were negative.