Rapid epidemiologic characterization of cytomegalovirus strains from pediatric bone marrow transplant patients.

BACKGROUND

DNA amplification by the polymerase chain reaction (PCR) of human cytomegalovirus (CMV) nucleotide sequences recently has been reported for differentiation of CMV strains.

DESIGN

Retrospective study.

OBJECTIVE AND PATIENTS

Evaluate the strain patterns of 15 CMV-positive buffy coat specimens from five pediatric bone marrow transplant patients.

SETTING

Pediatric bone marrow transplant unit.

METHODS

We perform PCR using primers corresponding to two distinct regions of the CMV genome, the major immediate-early (MIE) region and the a-sequence region, with subsequent restriction enzyme analysis of the amplified products.

RESULTS

Restriction enzyme analysis with Hae III and Hinf I of products amplified with nested PCR for the MIE region revealed distinguishable digestion patterns between patients but similar patterns for samples from each patient. All were distinct from the CMV Towne laboratory control strain. In contrast to these results, amplification of specimens with a-sequence primers, followed by restriction enzyme analysis, did not allow differentiation between all patients.

CONCLUSION

Our results indicate that nested amplification directly from buffy coat specimens using primers for the CMV MIE gene allows rapid CMV strain characterization that is useful for laboratory quality control and epidemiological studies. Distinct CMV strains were found in each patient, suggesting horizontal transmission was not responsible for acquisition of CMV infection in these patients.