Invasive streptococcal infection as a complication of chickenpox

Two girls aged 11 months and 6 years, presented with an invasive group A streptococcal (GAS) infection during the course of primary varicella. The infant had severe cellulitis of the left arm and leg, fever and bacteraemia. She developed osteomyelitis of ulna and tibia. The 6-year-old girl had a fever > 38.5 degrees C, hypotension, an acute respiratory distress syndrome, liver function abnormalities, and positive cultures of blood and joints. Her clinical picture was compatible with a GAS-associated toxic shock syndrome. If during the course of primary varicella persistent fever, secondary fever or pain in one or more extremities occurs, invasive bacterial infection by GAS or Staphylococcus aureus should be considered, even in the absence of skin infection or cellulitis.