An Eosinophilic Variant of Orbital Granulomatosis with Polyangiitis with Ocular Motility Disorder

Abstract

Purpose: To present the case of a patient with localized orbital granulomatosis with polyangiitis (GPA) characterized by a significant ocular motility disorder, increased eosinophilia, and hyper-immunoglobulin E (hyper-IgE).Case Summary: A 61-year-old male, with no previous history of allergy, atopy, asthma, sinonasal disease, respiratory disease, or renal disease, came to our hospital due to a 2-day history of binocular diplopia. His left eye exhibited inward and upward deviation, along with gaze limitation. His vision was 20/20 in both eyes, and the pupillary light reflex and color test were normal. He had severe eyelid swelling and conjunctival injection without tenderness in his left eye, and retinal vessel congestion around the optic nerve, without proptosis. Laboratory tests revealed a positive cytoplasmic antineutrophil cytoplasmic antibody (cANCA), a normal WBC count, elevated eosinophils at 28.3% (2,462/mm<sup>3</sup>), and high serum levels of IgE (400 KU/L). Magnetic resonance imaging showed an inferolateral orbital mass with an enlarged lacrimal gland and myositis of the extraocular muscles. A biopsy of the lacrimal gland revealed nonspecific chronic inflammation with an eosinophilic infiltrate. The presence of cANCA, in combination with clinical and pathological findings, led to the diagnosis of an eosinophilic variant of localized orbital GPA. This variant was primarily confined to the orbital tissue, marked by elevated eosinophil and IgE levels, and was treated with oral steroids without requiring surgery for the ocular motility disorder.Conclusions: GPA may present as acute strabismus with orbital inflammation, even in the absence of systemic signs. Therefore, it should be considered in the differential diagnosis of unexplained acute orbital syndromes.