[Serum antibody titers against various viruses in idiopathic interstitial pneumonia]

As the first step to investigate a possibility that viral infection is involved in the pathogenesis of idiopathic interstitial pneumonia (IIP), serum antibody titers against various viruses were studied in 98 IIP patients. The patients were positive for herpes simplex virus, cytomegalovirus, rubella virus, parainfluenza virus 3, EBV-VCA IgG and adeno virus 1, which were also assessed in 45 normal subjects. As results, IIP patients showed higher titers of EBV-VCA IgG (p less than 0.01). When the frequency of positive populations for each of the 6 viral antibodies was calculated, the values of the frequency in all the 6 viruses were found to be very high in both patients and normal subjects, and there was no significant difference between IIP patients and normal controls. In conclusion, a specific relationship between IIP and a certain viral infection was not observed by studying serum antibody titers against various viruses in IIP patients. It might be worthwhile studying why EBV-VCA IgG titers were shown to be significantly higher in IIP patients than in normals.