Supratentorial lymphocytic inflammation with parenchymal perivascular enhancement responsive to steroids: A case report and literature review

BACKGROUND: Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids is a rare disorder that presents with subacute brainstem symptoms such as ataxia, facial paresthesias, and episodic diplopia, thought to be due to a T-cell medicated perivascular inflammatory process. A supratentorial variant, Supratentorial Lymphocytic Inflammation with Parenchymal Perivascular Enhancement Responsive to Steroids (SLIPPERS), has been described in only three patients. CASE DESCRIPTION: A 71-year-old male presented with word-finding difficulties, confusion, and left leg weakness. Radiographic workup demonstrated multiple supratentorial ring-enhancing lesions. PET/CT demonstrated hypermetabolism and susceptibility-weighted imaging demonstrated a hemorrhagic component. Frozen pathology revealed a predominately T-cell and monocyte inflammatory infiltrate. He demonstrated interval improvement to dexamethasone therapy, but then demonstrated worsening of his symptoms following discontinuation. CONCLUSION: Given his dramatic response to corticosteroids, he was diagnosed with SLIPPERS. SLIPPERS is an underrecognized diagnostic entity to consider in patients with ring-enhancing lesions and can present with hypermetabolic lesions on PET/CT.