NEWS & EVENTS
Retinal Review, Issue 87
Authored by Burton Wisotsky, M.D.
A 54 year old man noted slight discoloration of his vision OS > OD over the past few weeks. He is in good health and has no ocular history. On examination VA was OD: 20/20 and OS: 20/25. IOP was normal OU. The SLE was significant for a few anterior segment cells OS > OD. DFE revealed a clear lens OU. There were vitreal cells OS > OD. See photos below:
Of note was a slightly hazy view OU. There was mild optic nerve edema OS > OD. There were large, yellowish lesions at the level of the deep retina/choroid scattered about both retinas. There were macular lesions as well, although only minimal if any CME was present.
Differential diagnosis includes inflammatory, infectious, and neoplastic etiologies. Whenever there is a “funny looking retina”, syphilis must be considered. Additionally, lyme disease, TB, fungal infection, sarcoidosis, and autoimmune disease can cause mild to moderate ocular inflammation with choroidopathy. We tested for all of the above – the tests were all negative. Two etiologies are left – white dot syndromes and ocular lymphoma. White dot syndromes are poorly understood, but are generally considered to be either idiopathic, or immune reactions to bodily insults such as influenza or viral infection. There are many different types – they can be distinguished by the retinal findings. Our patient’s findings are most consistent with Birdshot Chorioretinitis. This condition usually presents in middle age. It is idiopathic but is often associated with HLA A-29, a cell marker. The course is variable. Some patients have mild visual changes; others have significant inflammation – vision can be lost due to chronic CME, optic nerve atrophy, ERM, or retinal vascular damage. Patients often require systemic treatment with steroids or immune modulators to control inflammation. We told our patient that we would observe for the next week or two and obtain an HLA A-29 blood test for confirmation. A positive blood test is fairly specific for Birdshot, so we were hoping for a positive result. Unfortunately the test came back negative. We explained that the diagnosis of Birdshot was probable, but choroidal lymphoma could only be ruled out with diagnostic vitrectomy. We elected to watch and wait.
The patient’s course was significant for waxing and waning mild inflammation. He would develop iritis and vitritis accompanied by CME (see OCT images below).
The inflammation was mild and always controllable with topical therapy. His lesions have worsened over time (see photo progression), but there has been no evidence of a worsening infiltrative process to suggest choroidal lymphoma. Three years later his vision is OU: 20/20. He is on topical steroid once a day in each eye as well as a topical beta blocker. He has had an unusually mild course for Birdshot. Hopefully it will remain this way.