A case of primary Sjögren syndrome masquerading as post-COVID Bickerstaff encephalitis

Abstract

We present a case of acute external ophthalmoplegia, hypersomnolence, and ataxia occurring 5 days after an episode of SARS-CoV-2 upper respiratory tract infection. The patient’s serum returned positive for anti-GD1a antibodies. Guided by precedent cases, she was empirically started on a course of intravenous (IV) immunoglobulin for possible para-infectious Bickerstaff brainstem encephalitis (BBE). However, she failed to respond and subsequently developed autoimmune hemolytic anemia as well as renal tubular acidosis (type 1). Corroborative history from her family elucidated constitutional and sicca symptoms and she was eventually diagnosed with primary Sjögren syndrome (pSS) complicated by brainstem and cerebellar involvement. She was treated with IV cyclophosphamide and rituximab, after which her neurological deficits completely resolved at two months.