Infectious complications after hematopoietic stem cell transplantation: current status and future perspectives in Korea

Cho, Sung-Yeon; Lee, Hyeon-Jeong; Lee, Dong-Gun

A 10-year retrospective single-center study performed in Korea reported that CMV disease occurred in 2.9% of allogeneic HSCT recipients and 0.5% of autologous HSCT recipients. Pneumonia (38.6%), retinitis (36.4%), and enteritis (15.9%) frequently developed in patients with CMV infection. The average time of onset of CMV disease was 90 days after transplantation, ranging from 12 to 936 days [77] . Another study in the same institution reported that CMV DNAemia developed in about 51% of HSCT recipients [78] . CMV reactivation can be associated with a higher non-relapse mortality rate (RR, 1.61 to 1.95) [79] . In another report, 70% of HSCT recipients had experienced any level of CMV antigenemia, of whom 41% had received ganciclovir therapy for significant CMV reactivation and 4% had CMV diseases. However, this incidence could be underestimated because disease prevalence was not evaluated in all patients undergoing pre-emptive therapy [80] . Because the diagnosis of CMV disease is based on the pathology findings, the diagnosis might be limited depending on the patient's condition. Particularly for the diagnosis of CMV pneumonia, obtaining lung tissue from critically ill patients by transbronchial lung biopsy is problematic. One study aimed to measure the CMV level in bronchial washing fluid and suggest a cut-off for pneumonia diagnosis. CMV DNAemia of > 18,900 copies/mL (137,970 IU/mL) may be associated with CMV pneumonia in post-HSCT patients, as determined by the receiver operating characteristics curve [81] . However, further data are needed because it is difficult to distinguish whether the viral DNA in alveolar hemorrhage reflects viremia rather than lung tissue involvement, or whether CMV is detected as a bystander in bronchial washing fluid.