“A 21-day-old girl presented to the emergency department of an Ontario children’s hospital in early summer with a 1-day history of rash on the left arm and 3 days of decreased activity, poor feeding (not waking to feed, decreased volumes) and abdominal distension. She had no fever, weight loss, irritability, recent travel or known infectious contacts.
The neonate was a dichorionic diamniotic twin whose mother had been treated for hyperthyroidism during the pregnancy. Labour was induced at 37 weeks’ gestation for intrauterine growth restriction, and the twins were born by vaginal delivery. The patient’s mother had screened positive for Streptococcus agalactiae (group B streptococcus) on perineal swab culture and had received intrapartum prophylaxis with intravenous (IV) penicillin; however” ….