Systemic Lymphoma Masquerading as Birdshot Chorioretinopathy.

Purpose: To report a rare case of systemic lymphoma causing a birdshot-like chorioretinopathy (BSCR) in a histocompatibility leukocyte antigen (HLA)-A29 negative patient.

Methods: A 58-year-old man presented with a one year history of blurry vision and intermittent floaters. He had evidence of bilateral choroidal birdshot-like lesions which appeared atrophic without any vitritis. He had a history of low-grade B-cell lymphoma and chronic myeloid leukemia, both of which were diagnosed >10 years prior to presentation and treated with chemotherapy.

Results: The differential diagnosis of these birdshot-like lesions included autoimmune, neoplastic, and infectious etiologies. Work-up revealed a negative HLA-A29, and negative results for syphilis and tuberculosis. Magnetic resonance imaging (MRI) revealed enhancement of the trigeminal and oculomotor nerve cisternal segments but no overt evidence of malignancy. Full field electroretinogram (ffERG) and multifocal electroretinogram (mfERG) tests were within normal limits. Serial follow-up clinical examinations, retinal imaging, ffERG and mfERG demonstrated no disease progression. Two years after his initial consultation, he developed a paraspinal mass which was biopsied and found to be diffuse large B-cell lymphoma (DLBCL) and was treated with chemotherapy.

Conclusion: Clinicians should consider BSCR masquerade syndromes in patients that present with birdshot-like choroidal lesions with negative HLA-A29, history of lymphoma, or atypical characteristics. In this case, we suspect the patient's past low-grade B-cell lymphoma and chemotherapy resulted in the chronic choroidal findings. It is unclear whether choroidal involvement predisposes a patient to high-grade transformation to DLBCL. His ocular findings remained inactive throughout the treatment of his DLBCL.