CLIPPERS is a rare chronic inflammatory disorder of unknown cause that primarily affects the brainstem.
The name is a mnemonic for the key findings:
(1) chronic lymphocytic inflammation (CLI), predominantly angiocentric
(2) pontine perivascular enhancement (PPE) on MRI
(3) responsive to steroids (RS) and immunosuppression
Additional findings:
(1) Extrapontine involvement is common.
(2) The serum IgE is elevated.
(3) The protein concentration in the CSF is elevated.
Clinical findings:
(1) gait ataxia
(2) intermittent diplopia and/or nystagmus
(3) perioral and facial parethesias
(4) dysarthria
(5) variable cognitive deficits
(6) variable spastic paraparesis
The diagnosis requires exclusion of other causes (infectious, autoimmune, toxic, paraneoplastic, malignancy).
Differential diagnosis:
(1) malignant lymphoma
(2) Bickerstaff brainstem encephalitis
