Sepcific immunofluorescent IgG, IgM, and IgA antibodies in lymphocytic choriomeningitis.

In postnatally acquired lymphocytic choriomeningitis (LCM), specific immunofluorescent (IF) IgM antibody was found nearly in all the examined sera from 23 patients for 6-8 months after onset of the disease, IgA antibody in two-thirds of the patients and only during the first 5 weeks of the disease. In the first weeks, the titres of IF IgG and IgM antibodies reached values from 256-512 in some patients; IgA antibody titres were considerably lower. No specific IF IgM and IgA antibody was found in sera from 5 infants with prenatal LCM virus infection (3 infants with congenital hydrocephalus and chorioretinitis, 1 with cerebral palsy and chorioretinitis, and 1 with asymptomatic infection). IF IgM antibody in a titre of 4 was detected only in 2 specimens of the cerebrospinal fluid from one of the infants with hydrocephalus. It is suggested that in prenatal LCM virus infection the production of specific IgM antibody is more or less inhibited.