The clinical distinction between sarcoidosis and tuberculosis (TB) can be difficult.¹ Abnormal CD4 T cell function, demonstrated as cell mediated hyporesponsiveness (anergy), is considered to be a feature of sarcoidosis.² Here we report the use of a sensitive assessment of mycobacterial specific CD4 T cell response to assist in the diagnosis of sarcoid associated optic neuropathy in a subject at high risk of TB.

Case report

A 53 year old Asian-Indian woman was referred with a 2 month history of intermittent blurred vision in her right eye and right optic disc swelling. She developed right eye ache and her vision deteriorated over 3 days to counting fingers in this eye. She also complained of malaise and night sweats though her weight was stable. She had recently returned to the United Kingdom after living in Uganda. Examination revealed a right afferent pupillary defect, chronically swollen right …