Role of infection in Guillain-Barré syndrome: laboratory confirmation of herpesviruses in 41 cases.

Serological evidence of either acute cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infection was sought in a large series of patients with Guillain-Barré syndrome (GBS) and control subjects. Using an indirect immunofluorescent technique, IgM antibody directed against CMV was found in the serum of 33 of 220 GBS patients. The CMV-positive patients were mainly young adults (average age, 25.6 years), previously healthy, and the most common prodromal illness was mild coryza. Alternations in serum CMV IgM antibody level closely paralleled the patients' clinical course. Persistently elevated titers were found in patients with severe and protracted paralysis, whereas rapid disappearance of virus-specific IgM characterized benign cases. Striking time clusters of CMV-seropositive patients were found during three periods between January, 1971, and October, 1973. In a parallel study, EBV-specific IgM was found in 8 of 100 GBS patients (8%). All 8 also had heterophil antibodies. Thus, EBV and CMV appear related to a substantial number of cases of this primary demyelinating disease and, to date, are the two most common agents we have been able to link with GBS.