We describe a patient with aggressive systemic inflammatory pseudotumor manifesting as isolated ocular myasthenia gravis. In this case, the routine chest imaging performed following the diagnosis of myasthenia gravis identified occult mediastinal lymphoid disease years prior to development of diffuse systemic symptoms.
A 55-year-old man had intermittent left upper eyelid drooping and blurring of vision, worse later in the day, for 6 weeks. He had no significant medical history, no smoking history, and no systemic symptoms. The examination findings were notable for left upper eyelid ptosis with associated fatigability and Cogan twitch; the findings were otherwise normal. Acetylcholine receptor (AchR)–blocking antibody positivity (6.6 μm/L) and abnormal single-fiber electromyography confirmed the diagnosis of myasthenia gravis. Computed tomographic imaging of the chest revealed numerous lung nodules and mediastinal adenopathy, suggesting metastatic disease (Figure 1A).
Levin MH, Gopal PP, Galetta SL. Systemic Inflammatory Pseudotumor and Myasthenia Gravis. JAMA Ophthalmol. 2014;132(3):359-361. doi:10.1001/jamaophthalmol.2014.16