Which test result is typically negative in Kawasaki disease?

• A. Positive throat culture for Streptococcus
• B. Elevated antistreptolysin O titer
• C. Negative throat culture and negative ASO titer
• D. Elevated erythrocyte sedimentation rate

Answer: (C)

Kawasaki disease is a non-infectious febrile vasculitis in children, so it isn’t driven by an active Streptococcus infection. Because of that, throat cultures for Streptococcus are typically negative and the antistreptolysin O (ASO) titer is not elevated. Seeing both a negative throat culture and a negative ASO titer fits Kawasaki disease best, helping distinguish it from streptococcal pharyngitis or post-streptococcal rheumatic fever. In contrast, an elevated ESR is common in Kawasaki due to systemic inflammation, so that finding is not typical of a negative result.