eng Science and Education Publishing American Journal of Medical Case Reports 2374-216X 2019-07-18 7 9 197 199 10.12691/ajmcr-7-9-4 AJMCR2019794 article Hiro Matsukura matsukura-npr@umin.org 1 Shinichi Tsubata 2 Department of Pediatrics, Saiseikai Toyama Hospital Department of Pediatrics, Toyama Red Cross Hospital Acute appendicitis is the most common surgical emergency in children. A Japanese 8-year-old boy with attention deficit hyperactivity (ADHD) and comorbid autism spectrum disorder (ASD) exhibited fever, anorexia, and frequent vomiting. Gastrointestinal symptoms were initially regarded as associated with streptococcal pharyngitis and adverse effects of ADHD medication. Empirical antibiotic therapy did not improve his clinical condition. Absence of abdominal distension and tenderness led to a misled diagnosis and delayed diagnosis and treatment of acute appendicitis. Surgical intervention was made eventually for perforated appendicitis. He recovered without sequelae. Streptococcal pharyngitis with concurrent appendicitis is rare. Children with ASD sometimes have difficulty explaining their signs because of communication problems and insensitivity to pain. Special consideration is necessary when examining children with neurodevelopmental disorders, especially in emergency surgical conditions. http://pubs.sciepub.com/ajmcr/7/9/4/ajmcr-7-9-4.pdf appendectomy attention deficit hyperactivity (ADHD) autism spectrum disorder (ASD) methylphenidate hydrochloride strep test