Polyarteritis nodosa (PN) complicated with unilateral exophthalmos.

A 58-year-old woman suddenly developed right exophthalmos. A CT scan of her orbit revealed an increase in volume and density of extraocular muscles and intraorbital soft tissues that resembled exophthalmos in Graves' disease. The exophthalmos gradually improved without treatment. Two months later she developed mononeuritis multiplex in her limbs, and then showed a sudden onset of swelling of her right calf. Sural nerve biopsy was performed and the diagnosis of polyarteritis nodosa (PN) was established from the histological findings. A rare case of PN with exophthalmos is herein reported with a review of the literature.