Chronic Herpes Simplex Scleritis: Characterization of 9 Cases of an Underrecognized Clinical Entity

Abstract

To characterize in detail persistent and recalcitrant infectious scleritis resulting from herpes simplex virus (HSV). Retrospective and interventional clinical and immunopathologic case series. Nine patients with chronic scleral redness, edema, and pain refractory to conventional therapy underwent a scleroconjunctival biopsy for routine histopathologic evaluation and definitive immunodiagnosis for the presence of HSV. Immunofluorescent probing for HSV was performed on the patient specimens. Negative controls for HSV included elimination of anti-HSV and anti-varicella zoster virus antibody in the probing process and the use of normal human conjunctiva and sclera as substrates. Response to therapy with acyclovir was monitored and recorded. The average age of the affected patients was 50.2 years, and the average duration of symptoms before tissue diagnosis of herpetic scleritis was 3.2 years (median, 4 years). Three histopathologic patterns were discovered: granulomatous inflammation (2 cases), plasma cell-rich pyogenic granuloma-like pattern (1 case), and reactive fibroinflammatory pattern (6 cases). Herpes antigen was demonstrated uniformly by immunofluorescence in a perivascular distribution and less commonly in the interstitium. Varicella zoster virus was not detected, and all controls for nonspecific antibody reagent binding to tissue showed negative results. Acyclovir caused a dramatic improvement in the chronic or recurrent ocular inflammation in all instances, with an average duration of improvement of inflammation of 15.3 months. Unrecognized HSV infection can cause longstanding scleritis. Histopathologic features of HSV scleritis are varied and nonspecific; immunofluorescent demonstration of HSV protein can make a definitive diagnosis. Prolonged administration of acyclovir is required for effective therapy.