OBJECTIVETo explore the effect of CMV gB genotypes on viral load and treatment time in patients with CMV infection after hematopoietic stem cell transplantation (HSCT).

METHODSViral load was detected by real-time (RT) quantitative polymerase chain reaction (PCR) (Q-PCR), CMV gB genotypes by PCR restriction fragment length polymorphism (RFLP) (PCR-RFLP) in 115 patients with CMV infection (CMV-DNA positive) after HSCT during July 2004 and May 2010.

RESULTS(1) The distribution of CMV gB genotypes in HSCT recipients were as following: gB1, 42/115 (36.52%); gB2, 3/115 (2.61%); gB3, 43/115 (37.39%); gB4, 2/115 (1.74%). 20 patients (17.39%) had a combination of 2 different CMV genotypes and 5 patients (4.35%) had a CMV variant that lacked an RsaI digestion site, herein named gB5. (2) The median viral load were 2.7×10(3)(1.81×10(3) ∼ 6.03×10(4)) in gB1, 4.0×10(3) (1.32×10(3) ∼ 6.39×10(4)) in gB3 and 1.2×10(4)(2.28×10(3) ∼ 6.50×10(5)) in mixed gB. There was no statistical difference in viral load between gB1 and gB3 (P > 0.050). There was significantly statistical difference in viral load between single-gB (gB1 or gB3) and mixed-gB (P < 0.05). (3) The median treatment time was 17 days in mixed-gB and 14 days in single-gB. There was significantly statistical difference between two groups (P < 0.05). Conclusion gB genotype may have an impact on CMV DNA load and treatment time in HSCT recipients with CMV infection.