Clinical Update COMPREHENSIVE MRSA Ophthalmic Infection, Part 2: Focus on Orbital Cellulitis by gabrielle weiner, contributing writer interviewing preston h. blomquist, md, vikram d. durairaj, md, and david g. hwang, md rbital cellulitis is a poten- Acute MRSA Cellulitis tially sight- and life-threat- ening disease that tops the 1A 1B ophthalmology worry list. Add methicillin-resistant OStaphylococcus aureus (MRSA) to the mix of potential causative bacteria, and the level of concern rises even higher. MRSA has become a relatively prevalent cause of ophthalmic infec- tions; for example, one study showed that 89 percent of preseptal cellulitis S. aureus isolates are MRSA.1 And (1A) This 19-month-old boy presented with left periorbital edema and erythema preseptal cellulitis can rapidly develop five days after having been diagnosed in an ER with conjunctivitis and treated into the more worrisome condition of with oral and topical antibiotics. (1B) Axial CT image of the orbits with contrast orbital cellulitis if not treated promptly shows lacrimal gland abscess and globe displacement. and effectively. Moreover, the community-associ- and Hospital System in Dallas, 86 per- When to Suspect ated form of MRSA (CA-MRSA) now cent of those with preseptal cellulitis MRSA Orbital Cellulitis accounts for a larger proportion of and/or lid abscesses had CA-MRSA. Patients with orbital cellulitis com- ophthalmic cases than health care– These studies also found that preseptal monly complain of pain when moving associated MRSA (HA-MRSA). Thus, cellulitis was the most common oph- the eye, decreased vision, and limited many patients do not have the risk fac- thalmic MRSA presentation from 2000 eye movement. They may present with tors that would alert a physician that to 2009,2,3 followed by conjunctivitis, proptosis, an abnormal pupil, swelling an otherwise unimpressive eyelid le- corneal ulcer, endophthalmitis, and of the eyelid and/or under the con- sion could be the precursor of a serious orbital cellulitis; and the average age junctiva, and fever and discharge. drug-resistant infection. of patients was 32.7 years (standard Orbital cellulitis is commonly Part 1 of “MRSA Ophthalmic Infec- deviation [SD], 18.1 years). Why does caused by sinusitis or other nearby tion” (in last month’s EyeNet) provided CA-MRSA have such a strong predilec- infections, trauma, or prior surgery. an overview of current realities regard- tion for causing cellulitis? But the picture may be different when ing the prevalence of and increasing The answer appears to be that the MRSA is the cause. “If we see the threat posed by drug-resistant S. au- CA form of MRSA is associated with a telltale signs and symptoms of or- reus. This month focuses on diagnos- particular staphylococcal toxin known bital cellulitis in the absence of sinus ing and treating MRSA preseptal and as Panton-Valentine leukocidin, which disease, upper respiratory illness, or orbital cellulitis, which has an atypical causes tissue necrosis and leukocyte previous skin trauma, that raises a flag presentation and course. destruction. This toxin, a major factor for potential MRSA orbital infection,” in the etiology of abscesses of the skin explained Vikram D. Durairaj, MD, at CA-MRSA’s Link to Cellulitis and eyelids, is rarely produced by other the University of Colorado in Denver. In studies looking at patients with oph- types of S. aureus bacteria, whether “Diffuse lid swelling with multiple mathis mt et al. ophthalmology. 2012;119(6):1238-1243. thalmic MRSA in the Parkland Health HA-MRSA or methicillin sensitive. areas of involvement, such as the lac- eyenet 29 Comprehensive typical clinical course, and is getting Oral Antibiotics for Preseptal Cellulitis worse, practitioners should not hesitate to escalate care by involving an oculo- The following oral antibiotic regimens are appropriate choices for controlling mild to facial plastic and orbital surgeon,” Dr. moderate CA-MRSA infections, such as preseptal cellulitis and dacryocystitis. Durairaj advised. • Trimethoprim/sulfamethoxazole: loading dose of two double-strength tablets twice a day, then one tablet twice a day. Treatment for • Clindamycin: 450 mg three times a day. (Dr. Hwang advises watching for macro- Ocular MRSA Cellulitis lide-inducible resistance, which has about a 50 percent incidence.) Nip it in the bud. Given that Dr. Du- • Minocycline (preferable to doxycycline): 100 mg twice a day. rairaj’s paper reported that rapidly • Linezolid: 600 mg twice a day. (Watch for myelotoxicity, and be aware that line- progressing preseptal cellulitis was the zolid is extremely expensive, said Dr. Hwang.) primary predictor of MRSA orbital Plus: cellulitis, it’s important to intervene • Rifampin: 300 mg twice a day for five days, in combination with one of the anti- promptly. “Since Hib vaccination be- biotics listed above. came routine, we may have become complacent about preseptal celluli- rimal glands and extraocular muscles, in three of 15 patients. According to tis,” said Preston H. Blomquist, MD, also suggests a MRSA orbital infec- the authors, this finding is particularly at University of Texas Southwestern tion,” said Dr. Durairaj, who is one of significant for a pediatric popula- Medical Center. (Haemophilus influ- the coauthors of a recent paper that tion because prior studies have shown enzae was formerly the most common identified several distinctive features that orbital cellulitis in children is cause of orbital cellulitis, the incidence of atypical orbital cellulitis caused by frequently associated with paranasal of which has declined dramatically MRSA.4 sinus disease; and it could have major since the introduction of the Hib vac- Dr. Durairaj’s team retrospectively implications for diagnosis and man- cine in 1990.) “This finding wakes us analyzed the medical records of 15 agement of young patients. back up to the importance of monitor- patients with orbital cellulitis who Suspicious findings. Whenever a ing our preseptal cellulitis patients were culture positive for MRSA. The clinician sees a case of orbital cellulitis, closely. While it’s true that orbital cel- patients, with a mean age of 31.9 years he or she should have a high index of lulitis caused by MRSA doesn’t occur (range, 2-62 years; SD, 24.2 years), suspicion for MRSA, said Dr. Durairaj, that often, you have to be prepared for were managed by ophthalmic plastic but especially in endemic areas and in the threat,” he said. surgeons between January 2006 and patients with lid swelling and the fol- Preseptal cellulitis. Appropriate April 2009 at several institutions in the lowing characteristics: treatment for preseptal cellulitis in United States. The authors noted that n Presence of CA-MRSA endemic areas includes this is the largest case series of MRSA- • Lacrimal gland abscesses 1) empiric antibiotic coverage for CA- related orbital cellulitis published to • Multiple orbital abscesses MRSA and 2) incision and drainage date. n Absence of of any lid abscesses, according to Dr. Characteristics of MRSA orbital • Recent upper respiratory illness Blomquist. “Appropriate drainage is cellulitis. In this study, the MRSA- • Prior periorbital trauma the definitive management of many associated orbital cellulitis most com- • Adjacent paranasal sinus disease, skin and soft tissue infections and an monly presented as eyelid lesions with especially in the pediatric population important adjunct to antibiotic ther- lid swelling (preseptal cellulitis) that “If the orbital infection has an un- apy in deep, closed-space infections,” progressed rapidly, as was seen in 14 of usual presentation, is not following the he said. the 15 patients. Many of these patients stated that they first developed an MRSA Treatment Pointers eyelid lesion similar to a boil or stye, and the condition gradually worsened • Stay up to date on what organisms are endemic to your area. If CA-MRSA is en- to cellulitis with numerous microab- demic, change your practice to cover it, especially when treating preseptal cellulitis scesses along the lid margin. In a num- to prevent orbital cellulitis. ber of cases, these lesions were initially • Save the agent of last resort—vancomycin—for serious MRSA infections such as thought to be spider or insect bites on orbital cellulitis. the eyelid. • For mild to moderate infections, use older antibiotics that effectively cover CA- None of the patients had a preced- MRSA. ing upper respiratory infection, and • Use adequate dosing of appropriate antibiotics. Get in, hit hard, and get out. only one patient had a history of eyelid • If you suspect MRSA-related orbital cellulitis, consider immediate surgical drain- or other ocular trauma. Paranasal si- age of any focal abscess in addition to appropriate empiric antibiotic coverage. nus disease was uncommon, occurring 30 july 2013 Comprehensive Fortunately, CA-MRSA is suscep- 2 tible to several antibiotics, including Coming in the next tetracyclines and aminoglycosides (see “Oral Antibiotics for Preseptal Celluli- tis”). “One need not jump to vancomy- cin initially for nonsevere infections,” emphasized Dr. Blomquist, whose oral therapy for preseptal cellulitis is Feature double-strength trimethoprim/sulfa- Nutrition in the Fight methoxazole (two tablets twice daily), Against Eye Disease with or without rifampin. Beta-lactam antibiotics (e.g., penicillins and cepha- What is the role of diet and losporins) alone for preseptal cellu- UNDER THE SURFACE. Intraoperative supplementation in reducing litis should be avoided in CA-MRSA photograph shows