Acute infectious erythemas in children: a clinico-microbiological study.

One-hundred children with an acute illness comprising fever and widespread erythematous rash were prospectively studied to determine whether clinical presentations are helpful in defining the causative agent and to identify the most appropriate microbiological specimens. An infectious agent was identified in 65 children; 72% were viruses, 20% were bacteria, 5% were Mycoplasma pneumoniae and in 3% both viruses and bacteria were detected. The most common infectious agents were picornaviruses, an atypical presentation of measles and Group A beta-haemolytic Streptococcus. Different patterns of rash occurred with each of these infections. The clinical presentation of a child with an acute febrile illness and rash was unhelpful in defining the causative agent. Routine management should include a throat swab for bacterial investigation and in selected cases a blood sample for IgM viral titres.