Bilateral interstitial keratitis, erythema nodosum and atrial fibrillation as presenting signs of polyarteritis nodosa

PURPOSE: To report a case of Polyarteritis Nodosa (PAN) presenting as bilateral episcleritis and interstitial keratitis along with erythema nodosum and atrial fibrillation and to review the ophthalmic literature on PAN with anterior segment findings OBSERVATIONS: A 35-year old man presented with a two-month history of bilateral episcleritis, skin lesions consistent with erythema nodosum, joint effusions and episodes of prolonged diarrhea and atrial fibrillation. Ophthalmic examination was significant for bilateral diffuse episcleral injection and nummular corneal stromal infiltrates. The patient underwent an extensive infectious and inflammatory work-up that was negative except for a very elevated erythrocyte sedimentation rate (123 mm/h, normal < 20 mm/h) and C-reactive protein (51 mg/L, normal < 5 mg/L). In order to rule out inflammatory bowel disease upper endoscopy and colonoscopy were performed. Biopsies of the gastrointestinal mucosa were positive for a small- and medium-vessel necrotizing vasculitis consistent with polyarteritis nodosa. Disease control was achieved with systemic prednisone and azathioprine. Upon self-tapering both medications the patient developed hearing loss and interstitial keratitis recurred, hence the diagnosis of Cogan's syndrome/PAN was made. Intravenous pulse steroids were administered with resolution of his symptoms. The patient continues to be on azathioprine without disease recurrence for 1.5 years. Α review of the ophthalmic literature on PAN with anterior segment findings revealed only 10 cases; of these, 6 had originally presented with ocular manifestations alone (scleritis, peripheral ulcerative keratitis, episcleritis, dacryoadenitis) and 4 of these 6 were lethal due to delay in diagnosis. CONCLUSION AND IMPORTANCE: Early diagnosis of PAN is crucial, as the five-year mortality rate is close to 90%; upon initiation of systemic immunosuppression the mortality rate drops to 20%. Though PAN manifestations in the anterior segment are rare, a high index of suspicion is warranted in cases of bilateral episcleritis and interstitial keratitis.