034 – Recurrent aseptic meningoencephalitis as CNS manifestation of cryopyrin-associated syndrome in an adult patient heterozygous for the Q703K variant in exon 3 of the NLRP3 gene
Miriam Schülter (1) – Schuh Elisabeth (1) – Tania Kmpfel (1)
Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximillian University, Munich, Germany (1)
Cryopyrin-associated periodic syndrome (CAPS) is an autoinflammatory disorder (AID) caused by mutations in the NLRP3 gene. The p.Q703K variant is a low-penetrance mutation and has rarely been described in patients with central nervous system (CNS) involvement. We report the case of a 27-year-old male presenting with recurrent episodes of sterile meningoencephalitis. Cerebral magnetic resonance imaging (MRI) showed large FLAIR-hyperintense lesions involving basal ganglia, thalamus, pons and mesencephalon. Examination of cerebrospinal fluid revealed granulocytic pleocytosis, elevation of total protein and blood-brain-barrier dysfunction. Extensive laboratory testing showed no evidence for infectious, rheumatological or other inflammatory CNS diseases. Steroid treatment led to prompt improvement of clinical symptoms and MRI changes but clinical and MRI findings reoccurred after reduction of steroid therapy. Extensive molecular genetic testing for an AID including whole exome sequencing only revealed heterozygosity for the variant Q703K in exon 3 of the NLRP3 gene. Diagnosis of CAPS was made and anti-IL-1-treatment started. Steroid therapy could be reduced and the patient remained stable under this therapy regimen. This is an unusual case of a patient heterozygous for the Q703K variant with severe CNS manifestation who responded to anti-IL-1 therapy. It illustrates that CAPS should be considered in adult patients with recurrent sterile meningoencephalitis.