PANS is a clinical diagnosis not better explained by another diagnosis, based on examination and history; it is not based on one or a few tests. PANS can be triggered by infections, metabolic disturbances, and other inflammatory reactions. Infectious triggers include strep, upper respiratory infections, influenza, mycoplasma pneumonia, lyme borreliosis, and many others. PANDAS, a subset of PANS, requires a temporal relationship with Group A Streptococcal infections. Not all patients have a positive strep throat culture, and examination must be followed by ASO and ADB immune responses. Onset of symptoms can occur within days of contracting strep, or within several months of the inciting infection.