Table 2.

Key clinical differences between septic arthritis and adult-onset Still's disease (AOSD) in the context of postoperative fever—emphasizing diagnostic pitfalls and distinguishing features

Clinical features	Septic arthritis	AOSD
Fever	Most cases are mild and only 30%–40% of individuals have a temperature > 39℃	Peak fever and the highest temperatures (> 39 ℃) occurs at night
Arthralgia and arthritis	Most cases are monoarticular and only 10%−20% of individuals have a polyarticular disease	Most cases are polyarthritis
Dermatologic manifestations	Erythema around the affected joint	A macular or maculopapular evanescent salmon-pink skin rash appears together with the fever spikes
Pharyngalgia	Generally, not present, but can occur when accompanied by throat infections	It occurs before or during the first month of each disease flare
Others	Occur rarely but shivering can occur	It is common and includes myalgia, enlargement of the lymph nodes, splenomegaly, hepatomegaly, pleurisy, pericarditis, weight loss, etc