Table 2.

Main clues useful for differential diagnosis of hereditary periodic fever syndromes.

	Familial Mediterranean fever	Mevalonate kinase deficiency syndrome	Tumor necrosis factor receptor-associated periodic syndrome	Cryopyrin-associated periodic syndrome
Onset	Childhood or adolescence	Infancy (first year of life)	3–20 years	Neonatal period-childhood
Usual ethnicity	Armenian, nonsephardic Jews, Arab, Turkish people	Dutch and other Northern European populations	Firstly recognized in Northern European (Ireland and Scotland) people; any ethnicity	Panethnic
Fever duration	1–4 days	3–7 days	1 or even 3-4 weeks, usually responding to corticosteroids	Subcontinuous/variable with circadian periodism and intermittent flares
Abdominal distress	Very common (in the form of sterile peritonitis)	Very common (abdominal pain, vomiting, diarrhea)	Common (abdominal pain, diarrhea, constipation)	Uncommon
Chest involvement	Pleurisy, often unilateral	Infrequent	Pleuritis	Absent
Skin involvement	Erysipelas-like rash on feet/ankles	Polymorphic rash, erythema elevatum diutinum, disseminated superficial actinic porokeratosis	Painful migratory eruption, edematous plaques	Neutrophilic urticaria-like skin eruption of variable severity and extension (either induced by cold exposure or constant)
Osteoarticular involvement	Arthralgias or arthritides	Arthralgias	Migratory arthralgias, nonerosive arthritides	Arthralgias of variable severity, deforming osteoarthritis involving large joints and contiguous bones (in CINCA syndrome)