Case 1

A 6-month-old male was treated for bilateral purulent conjunctivitis with polymyxin B/trimethoprim ophthalmic solution with no relief of symptoms. The health care provider suspected a methicillin-resistant Staphylococcus aureus (MRSA) infection, ordered that a conjunctival swab be taken for bacterial culture, and prescribed oral cephalexin and trimethoprim/sulfamethoxazole to treat the infection while awaiting results of the culture. Two days later, the culture was positive for penicillin-nonsusceptible Streptococcus pneumoniae (PNSP). The provider stopped oral antibiotics and switched the ocular eye drops to a newer fluoroquinolone, which was effective.

Commentary
Had this provider known that the Sanford Guide¹ recommends newer fluoroquinolones as first-line treatment for bacterial conjunctivitis, the patient would most likely have been cured in 2 days. The expense of the second clinic visit, the laboratory testing, and the cost of the polymyxin B/trimethoprim eye drops, oral cephalexin, and oral trimethoprim/sulfamethoxazole treatments would have been spared.

The recommendations to treat with newer fluoroquinolones are supported by research evidence. For example, in 1 small study, moxifloxacin led to a higher proportion of patients experiencing complete resolution of ocular signs and symptoms at 48 hours compared to polymyxin B/trimethoprim eye drops (81% vs. 44%; P = .001).² Optimal treatment improves quality of life, reduces the spread of disease, and has a significant socioeconomic benefit.

References

1. Sanford J. The Sanford Guide to Antimicrobial Therapy 2010. 40th ed. Sperryville, VA: Antimicrobial Therapy Inc; 2010.
2. Granet DB, Dorfman M, Stroman D, Cockrum P. A multicenter comparison of polymyxin B sulfate/trimethoprim ophthalmic solution and moxifloxacin in the speed of clinical efficacy for the treatment of bacterial conjunctivitis. J Pediatr Ophthalmol Strabismus. 2008;45(6):352-351.