Muckle-Wells syndrome (MWS) is an intermediate form of cryopyrin-associated periodic syndrome (CAPS; see this term) and is characterized by recurrent fever (with malaise and chills), recurrent urticaria-like skin rash, sensorineural deafness, general signs of inflammation (eye redness, headaches, arthralgia/myalgia) and potentially life-threatening secondary amyloidosis (AA type).

Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium.