Lupus Cerebritis as a Rare Neuropsychiatric Manifestation of Systemic Lupus Erythematosus.

Mixed connective tissue disease (MCTD) is a rare autoimmune condition that shows an overlap of at least two connective tissue diseases (CTD) including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), scleroderma, Sjögren's syndrome, polymyositis, or dermatomyositis. From a laboratory standpoint, MCTD is associated with high titers of anti-U1-RNP antibodies, which makes it difficult to determine whether it is a variant of each of the respective CTDs or a different entity altogether. Our objective is to report the case of a patient with MCTD presenting with status epilepticus who was ultimately diagnosed with lupus cerebritis. The case also highlights the development of complications unrelated to MCTD that made the management even more challenging. Overall, the authors emphasize the rareness of lupus cerebritis as a presentation, the diagnostic challenges faced due to the lack of classical manifestations of SLE, and how the complicated clinical course makes a downhill prognosis more likely.