A Diagnostic Dilemma of Antiglutamic Acid Decarboxylase 65 (Anti-GAD 65) and Mycoplasma Pneumoniae Antibodies in a Girl Presenting with Acute-Onset Obsessive-Compulsive Disorder

Table 1

Differential diagnosis for CANS.

Infection	Metabolic	Drugs	Toxins	Autoimmune
Bacterial or viral meningitis, encephalitis, acute disseminated encephalomyelitis (ADEM)	Hypoglycemia, diabetic ketoacidosis (DKA), hyperammonemia, hyperthyroidism, hypothyroidism, uremia	Steroids, antihistamines, antipsychotics, phencyclidine (PCP), methamphetamine, benzodiazepines, anticholinergics, cannabis, cocaine	Organophosphates, heavy metals, alcohol	NMDA, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), GABA receptor antibodies, Hashimoto’s, antiphospholipid, systemic lupus erythematosus (SLE)
Vascular	Psychiatric	Idiopathic
Stroke, hypertensive emergency, subdural hemorrhage, epidural hemorrhage	Primary psychiatric disorder	No underlying etiology identified