Table 4.
Preliminary criteria of possible, probable, and definite autoimmune obsessive-compulsive disorders suggested by the authors.
| Possible autoimmune OCD* | Probable autoimmune OCD* | Definite autoimmune OCD* |
|---|---|---|
| (Sub)acute onset of OCD symptoms (< 3 months) AND/OR treatment resistance despite guideline-based therapy in combination with at least one of the following signs: | Combination of possible autoimmune OCD AND | Probable autoimmune OCD (suspected clinical and diagnostic findings) AND |
| • Atypical age of onset (early childhood or later adulthood) | at least two suspicious alterations in diagnostic investigations: | • Evidence for IgG neuronal antibodies in CSF and/or |
| • Atypical presentation of obsessive-compulsive symptoms (e.g., combination with severe hypersomnia or loss of function due to disproportionate cognitive deficits) | • Serum: Neuronal autoantibodies, “potentially neuronal” antibodies (e.g., ANAs against dsDNA), streptococcal antibodies | • Successful immunotherapy |
| • Accompanying neurological signs (movement disorder, focal neurological deficits, new seizures or headache) | • EEG: Signs of encephalopathy such as spike-wave activity or intermittent slowing | |
| • Autonomic dysfunction | • MRI: Basal ganglia/mesiotemporal hyperintensities, inflammatory lesions | |
| • Adverse response to antipsychotics (malignant neuroleptic syndrome) | • FDG-PET: Encephalitic patterns with disturbed metabolism in basal-ganglia, cortical or in temporal regions | |
| • Association of OCD onset with infections | • CSF: CSF-pleocytosis, CSF-specific oligoclonal bands, detection of (neuronal) autoantibodies, increased antibody indices | |
| • Comorbid autoimmune diseases (with potential brain involvement) | ||
| • Comorbid malignancies |
ANA antinuclear antibodies, OCD obsessive-compulsive disorder, dsDNA double strand deoxyribonucleic acid, EEG electroencephalography, MRI magnetic resonance imaging, FDG-PET [18F]fluorodeoxyglucose positron emission tomography, CSF cerebrospinal fluid, IgG immunoglobulin G.
The criteria are inspired by the concept of autoimmune psychosis by Pollak et al., 2020 [75]. These criteria should be evaluated and refined over time. *Classification as possible, probable, or definite autoimmune OCD requires exclusion of more likely alternative differential diagnoses (e.g., infectious, metabolic, toxic, “syndromal genetic” forms).