Co-occurrence of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids and posterior reversible encephalopathy syndrome: a case report.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a rare inflammatory disorder, mainly involving the brainstem. Posterior reversible encephalopathy syndrome (PRES) is a syndrome that affects the bilateral parietal-occipital region. Here, we describe a rare case of CLIPPERS with PRES. A 47-year-old woman presented with subacute, progressive ataxia symptoms, and radiological and pathological findings were consistent with CLIPPERS. In addition, she had acute convulsions and was unconscious, and brain magnetic resonance imaging fluid-attenuated inversion recovery showed patchy high-intensity posterior cerebral white matter signals, with imaging lesions showing vasogenic oedema, a typical manifestation of PRES. The imaging lesions showed vasogenic oedema in bilateral parietal and occipital lobes and typical 'pepper-like' punctate gadolinium enhancement in pons and bilateral cerebellar hemispheres, which were considered to be caused by merger of CLIPPERS and PRES. Clinical manifestations and imaging lesions disappeared after two months of steroids and symptomatic treatment, supporting the diagnosis of CLIPPERS with PRES. When patients with CLIPPERS show unusual symptoms or atypical vasogenic oedema lesions in the posterior cerebral white matter, the coexistence of PRES should be considered.