Severe invasive pyogenic streptococcal infection associated with varicella

Chickenpox and streptococcal tonsillitis are among the common childhood infectious diseases. In the vast majority of cases, these diseases progress without serious medical complications. However, in the last two years across Europe there has been a significant increase in severe invasive infections caused by Streptococcus pyogenes (Group A Streptococcus - GAS) with a transition to invasive forms of the disease (iGAS), mainly coinciding with ongoing varicella or other viral illnesses. In this case report, we present the clinical case of a 7-year-old immunocompetent boy with varicella who developed invasive streptococcal infection (iGAS) on day 4 of illness. Varicella was complicated by phlegmon on various parts of the body and bilateral bronchopneumonia with fluidothorax with respiratory failure. Streptoccocus pyogenes was cultured in the hemoculture. On combined antibiotic therapy (crystalloid penicillin G + clindamycin) and antiviral therapy, clinical status improved and inflammatory parameters decreased. Over the next few days, there was a reappearance of fever and development of phlegmonous fasciitis with myositis. Chest CT confirmed acute mediastinitis. The boy required intravenous antibiotic treatment with high-dose crystalloid penicillin G and ciprofloxacin for 3 more weeks. After discharge from the hospital, he was still taking oral penicillin for 2 weeks. On this treatment, the clinical, laboratory and CT findings were completely corrected. With the presented case report, we would like to appeal to paediatricians to be vigilant and to always think about the association of a common childhood disease with pyogenic streptococcus infection when characteristic clinical indications are present. Surveillance imaging and a detailed history led us to a serious diagnosis, with high lethality. Clinical experience shows that bacterial strains sensitive in vitro may not be sensitive enough in vivo; when the clinical condition of a child with varicella deteriorates rapidly, the potential development of GAS or iGAS disease must be considered. (author)