A case of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) with the largest lesion in the temporal lobe.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory disease of the central nervous system with a predilection for the hindbrain. Generally, lesions decrease in size with increasing distance from the hindbrain. We herein describe a case of CLIPPERS in a patient showing the largest lesions in the temporal lobe. A 49-year-old man consulted to our hospital with a 22-day history of a high fever and an abnormal visual field involving the left eye. Brain MRI showed a FLAIR hyperintense lesion in the right temporal lobe with punctate gadolinium enhancement. Several days later, lesions showing similar enhancement extended to the pons, medulla oblongata, and cerebellar hemispheres. Biopsy of the right temporal lobe lesion revealed perivascular lymphocytic infiltrates without any findings of demyelination, lymphoma, or glioma. He was diagnosed with CLIPPERS based on clinical, radiological, and histopathological findings. Clinical and radiological findings improved quickly after steroid therapy. CLIPPERS could represent larger lesions distant from the hindbrain showing punctate enhancement.