Relapsing polychondritis (RP) is a rare disorder that is characterised by recurrent and progressive inflammation of cartilaginous structures.1 Nervous system involvement in RP has been described.1^–5 We describe two cases of RP with subacute dementia.

Case 1

A 51-year-old lawyer was diagnosed with RP when he presented with bilateral ear swelling. He was treated with 10 mg/day of oral prednisone during this attack, with a brief taper. He continued to have flare-ups during the next several years and was treated with a short duration of prednisone ranging from 10 to 40 mg/day. Episodes of iritis and scleritis were treated with steroid eye drops. One year after the diagnosis of RP, he started to experience gradual-onset coordination problems, difficulty presenting verbal arguments, distractibility and emotional lability. He developed insomnia and nocturnal myoclonic jerks. Neuropsychological evaluation showed perseveration, prominent attention and concentration deficits. Brain MRI showed extensive periventricular and deep white matter high-signal abnormalities. There was reduced metabolic activity in bilateral temporal cortices and parietal lobes on PET scan. Electroencephalogram was normal. Cerebrospinal fluid (CSF) contained 89 mg/dL of protein, 52 mg/dL glucose, 39 white blood cells (WBCs) (65% lymphocytes) and 2 red blood cells (RBCs). CSF tau/amyloid levels and ratio were considered to …