Fluorescent EBV antibodies in infectious mononucleosis.

Abstract

The fluorescent EBV antibodies in infectious mononucleosis (IM) have been studied in 33 patients admitted to hospital with a diagnosis of IM and bled at intervals over periods from 5 to 16 weeks after onset of illness. EBV antibodies were demonstrable in all these patients. In 18 patients, maximum titres up to 2560 appeared already in the first blood specimen obtained. A slight decrease in titre was seen in these patients during the first month of illness, after which period the titres remained constant. A significant rise in antibody titre was demonstrated in sera from only 3 patients, while 13 patients showed no change in titre. The control group consisted of 24 apparently healthy individuals and 11 patients suffering from diseases other than IM. In sera from one of these patients and from 7 of the healthy persons, EBV antibodies were not demonstrable while sera from the rest of the control group showed titres ranging from 10 to 640. Studies of blood samples from 4 persons obtained over a period of 15 years show that EBV antibodies persist for this length of time without change in titre. The results show that the actual titre value of fluorescent EBV antibodies may be of very limited diagnostic significance in IM. In order to demonstrate a rise in titre it seems necessary to obtain blood specimens before or immediately after onset of illness.