Sacroiliitis infected with group A streptococcus in a child presenting with confusion and combativeness

Group A streptococcus-associated severe invasive infection (streptococcal toxic shock syndrome) has been described. Streptococcal toxic shock syndrome occurs when the infecting strain of group A streptococcus produces superantigens. Confusion and combativeness are well known as the common symptoms of streptococcal toxic shock syndrome. We encountered a child who suffered from pyogenic sacroiliitis, with confusion and combativeness. Group A streptococcus was isolated from the patient’s blood culture. However, his disease did not fulfill the criteria of streptococcal toxic shock syndrome. Pyogenic sacroiliitis in children is rare, but patients with pyogenic sacroiliitis due to group A streptococcus infection could show confusion and combativeness as clinical signs, similar to the signs in streptococcal toxic shock syndrome.