Measles virus antigen in panencephalitis. An immunomorphological study stressing dendritic involvement in SSPE.

Abstract

In a retrospective study of 42 cases with a histopathologic diagnosis of subacute sclerosing panencephalitis (SSPE) or similar panencephalitic processes, measles virus antigen was traced by means of indirect immunofluorescence (IF) and peroxidase-antiperoxidase (PAP) techniques on protease-pretreated histological sections from formol-fixed, paraffin-embedded brain biopsy or autopsy tissue, stored for up to 32 years. Measles virus antigen was detected in 28 brains which were thus definitely diagnosed as SSPE or in one case as subacute measles encephalitis under immunosuppression. These cases were divided into three groups: group A, nine brains with excessive antigen amounts; group B, seven cases with a patchy distribution of a moderate number of antigen-containing cells; and group C, twelve cases with very few scattered reacting cells. Patients with excessive antigen amounts usually died at an earlier age and after a shorter course than cases with very few antigen-containing cells. An adult onset (beyond 20 years) was seen in five patients. The brain of a 5-day-old baby born to an SSPE mother did not contain any measles virus antigen. Complement fixing measles serum antibody titers were negative or low in four patients with measles virus antigen in the brain. Most of the cases found to be negative for measles virus antigen in the brain did not show clinical and/or histopathologic features of typical SSPE, including cases with a “pseudosystemic” lesion pattern.