In Table 1, the characteristics of the 77 heart transplant recipients are shown. A total of 41 of 77 (53 percent) patients were CMV seropositive at the time of transplantation. Twenty of the 36 CMV seronegative patients received an allograft from a seropositive donor. One CMV seronegative patient received two allografts, the first from a CMV seronegative and the second from a CMV seropositive donor. Six out of the 77 patients died within 14 days after transplantation because of a noninfectious complication and were excluded from further analysis. In 46 (65 percent) of the remaining patients, at least one antirejection therapy was instituted. Fifteen patients were treated with RATG.
The follow-up in the 71 patients was six to 39 (median 19) months after transplantation. A total number of 221 infusions of anti-CMV immunoglobulin was given in 32 patients. In two patients, during the sixth and seventh infusion respectively, a rash neces­sitated discontinuation of the globulin treatment. No hemodynamic side-effects were recorded. In the other 30 patients, no side-effects were observed.
Table 2 shows the incidence of CMV isolation and disease in four groups of heart transplant recipients, according to the CMV serostatus of donor/recipient and passive immunization. One out of 16 treated seronegative heart recipients from a seronegative donor developed symptomatic CMV infection at ten weeks after transplantation, one week after the start of antirejection therapy with RATG. In eight of 16 (50 percent) treated CMV seronegative heart recipients from a seropositive donor, CMV could be isolated at a median of 40 (range 17 to 240) days after transplanta­tion. In seven patients, CMV was isolated from the blood. Three of these patients had been treated with RATG. Two developed CMV-related symptoms. In both patients, lung involvement was present and one patient was treated with DHPG. None of the symp­tomatic patients died because of CMV infection.
One of the globulin-treated CMV seronegative heart recipients from a CMV seropositive donor developed CMV-related symptoms 27 weeks after transplanta­tion, when the anti-CMV IgG serum level had de­creased <100. During the immunoprophylactic pe­riod, this patient was viremic without accompanying symptoms.
The incidence of CMV isolation in the 38 seroposi­tive recipients was 42 percent. The first isolation of CMV isolation was observed at a median of 47 (range seven to 300) days after transplantation. In four patients, viremia was diagnosed and all four developed CMV-related disease. Two patients were treated with DHPG. One patient died because of CMV lung involvement.
One of the two untreated CMV seronegative recip­ients from a CMV seropositive donor developed CMV disease.
Based on the data from the literature, the expected incidence of CMV disease in CMV seronegative recip­ients from a CMV seropositive donor was 82 percent (36 of 44). This would mean for our study group 13 patients with CMV disease. The observed incidence was two of 16 (13 percent). The difference between observed and expected incidence was 69 percent (95 percent CI 42-97 percent, p<0.001).