Predicting bacterial cause in infectious conjunctivitis

Editor—It seems churlish to quibble with such an interesting study as that by Rietveld et al on predicting bacterial cause in infectious conjunctivitis,¹ but aren't there more important questions?

How much harm do general practitioners do when they prescribe antibiotics? The real damage is done when keratitis is missed, the steroid often given with the antibiotic being the bigger culprit. Steroids will dampen the immune response, permitting resistant corneal pathogens to mushroom. In early keratitis this causes a notable delay in referral. Patients believe that they are better because the eye is less red—until vision drops. Detecting small corneal lesions without a slit lamp is all but impossible. A few pertinent questions may help prevent corneal scarring and visual loss.

The most useful are: “Do you wear contact lenses?” “Does your eye hurt, or does bright light hurt you?” “Is your vision worse?” If the answer to any of these is yes, don't prescribe, but refer. If you can't, give contact lens wearers an antibiotic that works for Pseudomonas—without steroids.