Table 1.

PFAPA classification criteria

Criteria	Description	Sensitivity*	Specificity*
Modified Marshall’s (1999) [42]	- Periodic fever episodes (onset typically < 5 years old) - Pharyngitis - Aphthous stomatitis - Cervical adenitis - Symptom-free intervals between attacks	Moderate	Low
Cantarini et al. (2017) (Late-onset PFAPA) [4]	- Onset at ≥ 16 years - Recurrent fever episodes - Pharyngitis and cervical adenitis (may or may not include aphthous stomatitis) - Absence of other periodic fever syndromes	High	High
Vanoni et al. (2018) (Eurofever/PRINTO) [43]	1. Periodic fever for at least 6 months: a. Fever ≥ 38.5 °C (axillary) for 2–7 days b. At least five regularly recurring fever episodes with a maximum interval of 2 months between them 2. Pharyngitis, cervical adenitis, or oral aphthae: at least one in every episode and at least two out of three in the majority of episodes 3. Exclusion of other causes of recurrent fever (clinical or laboratory evaluation) 4. Exclusion of infections, immunodeficiency, and cyclic neutropenia 5. Disease onset before 6 years of age 6. Complete resolution between episodes 7. Normal linear growth	High	High
EUROFEVER/PRINTO (2019) (revised criteria) [2]	At least 7 of the following 8 criteria: - Pharyngotonsillitis - Fever lasting 3–6 days - Cervical lymphadenitis - Clockwise periodicity of fever episodes - No diarrhea - No chest pain - No skin rash - No arthritis	0.97	0.93

^*Sensitivity and specificity are classified as high (≥ 90%), moderate (70–89%), or low (< 70%) on the basis of their ability to correctly identify or exclude PFAPA cases in validation studies