The diagnosis is clinical, not based upon serology. At least seven sets of diagnostic criteria have been devised, however the Yamaguchi criteria have the highest sensitivity. Diagnosis requires at least five features, with at least two of these being major diagnostic criteria. Major criteria Minor criteria Fever of at least 39 °C for at least one week Sore throat Arthralgias or arthritis for at least two weeks Lymphadenopathy Nonpruritic salmon-colored rash (usually over trunk or extremities while febrile) Hepatomegaly or splenomegaly Leukocytosis (10,000/microL or greater), with granulocyte predominance Abnormal liver function tests Negative tests for antinuclear antibody and rheumatoid factor Classification People with<unk>  generally experience one of two patterns in the<unk> : * a debilitating pattern of fevers, pain, and other systemic symptoms, or * a somewhat less aggressive pattern, in which the main symptom is arthritis and chronic joint pain. One set of 21<unk>  patients were divided into four types, according to clinical course patterns. These included monocyclic systemic<unk> , polycyclic systemic<unk> , chronic articular monocyclic systemic<unk> , and chronic articular polycyclic systemic<unk> . People with chronic articular<unk>  and polyarticular<unk>  were at higher risk to develop disabling arthritis.
Adult-onset Still's disease
Boutonneuse fever
Far East scarlet-like fever
Barcoo fever
Tomato fever
Haverhill fever
Murine typhus
Quartan fever