1. From the Hospital for Children and Adolescents, University of Helsinki, Finland;
2. Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Finland;
3. Department of Obstetrics and Gynecology, University of Helsinki, Finland;
4. Rheumatism Foundation Hospital, Heinola, Finland;
5. Department of Medicine, Division of Infectious Diseases, University of Helsinki, Finland.