Clinical and laboratory evaluation of measleslike rash in children and young adults

A clinical and laboratory evaluation of Il children and young adults with m easleslike rash was done during the measles outbreak in the Greater Sao Pau lo Metropolitan area at the end of 1996 and spread over the country during 1997. Measles was laboratory confirmed in 07 patients by specific IgM detec tion in acute serum specimens using an IgM-capture EIA, by specific IgG ser oconversion in serum pairs, and by reverse transcription PCR and virus isol ation in peripheral blood lymphocytes. Clinical presentations were not alwa ys classic; one of the 07 cases had received measles vaccine and correspond ed to modified clinical case of measles. The 4 remaining cases were negativ e for measles and were diagnosed as exanthem subitum (2 cases), scarlet fev er and Kawasaki disease. The present study reinforces the view that clinica l features alone are not sufficient for establishing an accurate diagnosis in the post-vaccine era, and a surveillance system based on sensitive labor atory results is needed so that it can confirm IgM-negative measles cases.