Differentiating Herpes Simplex Keratitis

Herpes is caused by an Epstein-Barr virus and is often confused with other organisms as the etiology of Keratitis. Most often a patient will present with red, painful eyes that can be caused by many things. Careful examination is required to properly diagnose and then treat these individuals.

Herpes Keratitis is usually diagnosed by the dendritic ulcers. They most often appear with a dendritic epithelial pattern that is ulcerated and has branching lines that end with terminal end bulbs. It is extremely painful and causes substantial photo phobia. The problem exists when there is a dendritic appearing lesion that is not well defined. The initial diagnosis may be Herpes, but upon closer examination a few days later the lesion lacks the defining entities that only Herpes Keratitis would have. Treatment must be closely followed and modified accordingly. The use of antiviral meds should reduce the lesions and improve the condition. If this does not occur, then there has been a misdiagnosis and treatment must be changed. Frequently, Acanthamoeba may be the agent that needs to be treated. Initially, the dendritic lesions will appear the same minus the end bulbs, but when the antivirals do not work, antibiotic meds must me introduced as soon as possible. In addition, if any steroids were employed, then they may have exacerbated the Acanthamoeba lesions. Obviously it is always indicated to take a culture at the beginning of treatment, but the condition may require treatment modification prior to getting the lab results back.

In short, always consider that the initial diagnosis may not be correct if the treatment does not fully re mediate the symptoms in a timely fashion. With regard to Herpes Keratitis, consider Acanthamoeba Keratitis as an alte
ative diagnosis early in the treatment period.