ASSOCIATION BETWEEN FEVER AND SERUM INTERLEUKIN-6 LEVELS IN CHILDREN WITH GROUP-A BETA-HEMOLYTIC STREPTOCOCCAL INFECTION

1. The serum levels of interleukin (IL)-1 beta, IL-6 and granulocyte c olony-stimulating factor (G-CSF) were measured in children with Group A beta-hemolytic streptococcal (GABHS) infection using sensitive immun oassays. 2. Serum IL-6 levels were elevated in 21/27 patients during t he phase of GABHS antigen-detection, significantly higher than in heal thy control children (P < 0.01). Levels of IL-1 were undetectable in a ll but one sample. 3. The IL-6 level peaked on day 3 of the infection, then decreased. The IL-6 levels were significantly associated with th e duration of fever (P < 0.05) and the maximum body temperature (BT) ( P < 0.05), but not with the BT at time of blood sampling, C-reactive p rotein levels or leukocyte counts. 4. Levels of G-CSF were slightly hi gher in the patients with infection than in the controls (P < 0.05), b ut were not correlated with any other parameter including neutrophil c ounts. 5. These cytokine levels neither reflected a differing T-seroty pe infection, nor did they vary among patients with regard to the pres ence of skin eruptions and the carrier state. 6. These observations su ggest that IL-6, but not IL-1, is produced during the acute phase of G ABHS infection, accounting for the febrile condition as an inflammator y cytokine, despite the serotype of the infecting organism or the clin ical types of infection.