Ophthalmoparesis associated with IgG4-related disease: a case report

Abstract

Case Presentation: A 60-year-old female patient with fibromyalgia was admitted due to severe, continuous, pulsatile headache in the right frontotemporal region that began one month after head trauma caused by a bottle injury. The pain was associated with photophobia, phonophobia, tearing, and blurred vision. Ten days after the onset of symptoms, she developed a contralateral headache accompanied by periorbital pain and scleral hyperemia in both eyes, progressing to convergent strabismus and decreased visual acuity in the left eye, without diplopia. On admission examination, she presented with strabismus associated with paresis of the left lateral rectus muscle, as well as chemosis in the left eye. Orbital magnetic resonance imaging showed thickening of the muscle bellies of the bilateral lateral rectus muscles and the right medial rectus muscle, in addition to enlargement of the left lacrimal gland. Cerebrospinal fluid analysis was normal. A biopsy of the lateral rectus muscle confirmed IgG4-related disease. The patient was started on pulse therapy (methylprednisolone 1 g/day) and evolved with significant clinical improvement. Discussion: IgG4-related disease is a chronic, immune-mediated systemic condition characterized by fibroinflammatory infiltration of multiple organs induced by IgG4-expressing plasma cells. It is a rare condition affecting approximately 2.2 per 100,000 people, mainly men over 50 years of age; however, precise estimates are challenging due to the limited number of studies and variable diagnostic criteria. The disease may mimic other prevalent conditions, such as lymphoma, lymphomatoid granulomatosis, and Sjögren’s syndrome, which may lead to delayed diagnosis and unnecessary medical or surgical treatment. Final Comments: The presented case had an atypical clinical presentation, involving a female patient with bilateral ocular muscle involvement, evolving with convergent strabismus and severe ophthalmoparesis, findings that are uncommon in IgG4-related disease. Considering the wide range of diseases that can affect the muscles responsible for ocular movements, this case report is relevant to neurological practice, as it demonstrates an unusual clinical presentation and highlights the importance of careful diagnostic investigation, even in the presence of atypical manifestations. Furthermore, due to the disease’s potential to mimic other conditions, it is essential to include it among the differential diagnoses in multisystem disorders.