All Participants:

Unacceptable risk of harm to participant or study staff due to risk of behavioural disturbance.

Inability to have blood tests.

Optional Lumbar Puncture only:

Significant lower spinal deformity (such as spina bifida), injury, or disease (such as stenosis) or previous lower spinal surgery.

Antiplatelet or anticoagulant therapy within the 14 days prior to Lumbar Puncture procedure.

Known or suspected clotting disorder.

Clinically significant abnormality in full blood count.

Known or suspected raised intracranial pressure, assessed by study clinician.

Known or suspected allergy to local anaesthetic agent or an ingredient of the anaesthetic solution.

History of chronic or recurrent headaches, in the opinion of the investigator.

Dissecting Immunological and Autoimmune Mechanisms of Neuropsychiatric Diseases