Cytomegalovirus Retinitis in a Patient on Long-term Mycophenolate Mofetil Treatment for Myasthenia Gravis

A 64-year-old man with myasthenia gravis (MG) presented with blurry vision in his left eye (OS). His visual acuity was 20/20 in the right eye and 20/50 OS. His intraocular pressures, pupils, and anterior segment were normal. He had 1+ vitritis and vaso-occlusive appearance of the retina with sclerotic vessels and hemorrhages in the inferonasal quadrant OS (Figure 1), consistent with features of cytomegalovirus (CMV) retinitis. He was immunocompromised secondary to mycophenolate mofetil (MMF) administered for MG, with 0.6% lymphocytes (normal: 26.0–46.0%), a lymphocyte count of 0.1×103 cells/μL, and a leukocyte count of 11.3×103 cells/μL. He was receiving 1000 mg of MMF BID. The human immunodeficiency virus (HIV) test result was negative, and no further workup for immunosuppression, including cancer, was conducted.