Chronic relapsing pericarditis and dilated cardiomyopathy: serological evidence of persistent enterovirus infection.

By means of two different IgM-capture assays, enterovirus-specific IgM responses were shown in 9 of 14 (64%) patients with chronic relapsing pericarditis. This finding suggests persistent enterovirus infection, particularly coxsackie B virus infection. IgM responses persisted for at least 1 year and for up to 10 years after onset of symptoms. In contrast, patients with acute enterovirus infections, including acute pericarditis, had transient responses. Among patients with acute pericarditis, the level of IgM antibody was significantly higher in those who subsequently relapsed (mean 1.21, range 0.6-2.0 optical density [OD] units) than in those who did not (0.4, 0.2-0.9 OD units; p less than 0.01). Of 86 patients with dilated cardiomyopathy, 28 (33%) showed enterovirus-specific IgM responses which were present for up to 19 months before transplantation and persisted up to 4 years afterwards. Although the distribution of HLA types in these patients was similar to that in the general population, the frequency of the HLA A2 haplotype was significantly higher in those who were IgM positive. IgM antibody was significantly more common in those who had had symptoms for longer than a year before transplantation than in those with a shorter duration of symptoms (1 of 21 vs 8 of 23; p less than 0.02). Persistent virus-specific serum IgA responses were also shown in patients with chronic cardiac disease.