Autologous Bone Marrow Transplantation - Blog Science Connections

612 Herpesvirus Infections
Table 3. The Contribution of Graft-versus-Host Disease to the Risk for CMV
Pneumonitis After Bone Marrow Transplantation
Type of Transplant Acute GVHD Proportion With CMV Pneumonitis
Autologous — 3 of 143 (2%) a
Allogeneic No 9 of 168 (5%) a
Allogeneic Yes 36 of 218 (16%)' ,fi
Abbreviations: CMV, cytomegalovirus; GVHD, graft-versus-host disease.
S
P = .000003.
b
P = .001.
prevention of CMV infection or CMV pneumonia, although not universally so
(9): One preliminary report suggested a beneficial effect of CMV immunoglobulin
in treating CMV pneumonia (10) and another did not (11). Furthermore,
the benefit has occurred largely in patients who are seronegative prior
to transplantation. An alternative strategy is the screening of blood products
for evidence of contamination by CMV. Studies performed in a variety of
patient populations including those with bone marrow transplantation (9, our
unpublished observations) have demonstrated the ability to prevent CMV
infection when only CMV seronegative blood products are used. An added
benefit may be a more rapid recovery of platelets and reduced need for
platelet transfusion support (12).
Although gancyclovir (DHPG) (9 [ l-3-dihydroxyl-2-propoxymethyl] guanine)
has been shown to have potent anti-CMV activity in vitro and has shown
beneficial effects in the treatment of CMV retinitis in patients with the acquired
immune deficiency syndrome ( 13,14), it has had very little beneficial effect in
bone marrow recipients with CMV pneumonitis (15). Acyclovir given prophylactically
in standard doses has not been effective in preventing CMV pneumonia
after marrow transplantation, but a preliminary study that employed
twice the standard dose (500 mg/m 2 every 8 hours administered from day -5
to day 25) has recently been reported to reduce CMV infection and pneumonia
in patients who received allogeneic bone marrow ( 16). Although this
was not a randomized trial, preliminary analysis of the various risk factors for
CMV pneumonia did not reveal any other variable that might have accounted
for this beneficial effect. Further analysis of this data is under way.
The frequency of reactivation of varicella zoster virus (VZV) and the
severity of infection has not been studied in detail after ABMT. It has been our
impression that, as with VZV infection after allogeneic transplantation, reactivation
is common, occurs several months after transplantation, and frequently
disseminates. Because VZV is less susceptible to acyclovir than HSV (17),
higher blood levels are needed to inhibit the virus. In general, because of poor
absorption of acyclovir after oral administration, adequate blood levels of the
drug are not achieved for prolonged periods. Accordingly, administering oral
acyclovir to patients with high risk of dissemination should be discouraged. In