A 41-year-old Hispanic female with history of primary biliary cholangitis/autoimmune hepatitis overlap, presented with first-time seizure. Brain magnetic resonance imaging raised a suspicion of right frontal hypertrophic pachymeningitis (HP) (1.2 cm) with midline shift. Cerebrospinal fluid (CSF) studies showed: normal cell count, normal CSF protein, normal angiotensin converting enzyme, negative CSF oligoclonal immunoglobulin G (IgG) bands, elevated CSF IgG index (1.6) and elevated CSF soluble interleukin-2 (sIL-2) receptor (107.0 pg/mL; reference,  £26.8). CSF hematopathology analysis reported no blasts or malignant cells, and infectious CSF work-up was negative. Blood work up revealed: elevated sIL-2 receptor (1133.0 pg/ml; reference, 175.3-858.2), positive antinuclear antibody (Ab) (≥1:2560), positive centromere IgG, negative antineutrophil cytoplasmic Ab, negative anti- Sjögren's-syndrome-related antigen A/B Abs, negative rheumatoid factor, normal IgG4 level, and negative infectious work-up. Lipoprotein metabolism profile evaluation showed elevated total cholesterol, low-density lipoprotein (LDL) and triglycerides, low high-density lipoprotein, and the presence of LpX. Genetic familial hypercholesterolemia and comprehensive lipidemia panels were unrevealing. Dural biopsy was suggestive of xanthogranulomatous inflammation and staining identified no fungi, spirochetes, acid-fast bacteria, or other bacteria. Skin biopsy confirmed xanthogranulomas. The patient was treated with immunosuppression, antiseizure medications, cholesterol and trygliceride- lowering agents, LDL pheresis, however due to multiorgan failure and infectious complications the outcome was poor.