Detection and monitoring of cytomegalovirus infection in renal transplant patients by quantitative real-time PCR.
OBJECTIVE
To establish a sensitive and specific real-time PCR for quantitation of cytomegalovirus (CMV) DNA in clinical specimens.


METHODS
In a prospective study, CMV DNA was quantified in blood samples of 255 kidney recipients with and without CMV-related symptoms between the years 2000 and 2005 in Kuwait. In a selected group of patients, the effect of anti-CMV chemotherapy was monitored by quantitative real-time PCR (qRT-PCR).


RESULTS
The established qRT-PCR assay had a sensitivity to detect 30 CMV DNA copies. CMV DNA was detected in 54/255 (24%) patients; of these, 17 (31.5%) were asymptomatic, and 37 patients (68.5%) had symptomatic CMV infection. Sequential blood specimens were collected from all CMV-positive patients and tested by CMV pp65 antigenemia and qRT-PCR assays. There was a moderate positive correlation between the two assays (Pearson's correlation = 0.52). The median CMV viral load measured by qRT-PCR was higher in symptomatic (6.5 x 10(4) copies/ml) than in asymptomatic (185copies/ml) patients (p = 0.001). The estimated cut-off value of CMV DNA for CMV symptoms/disease was > or =800 copies/ml of blood. Testing of sequential samples from patients treated with symptomatic CMV infection showed that the viral load was significantly reduced after 3 weeks of anti-CMV chemotherapy (p = 0.001).


CONCLUSIONS
The reported qRT-PCR is a sensitive method for quantitation of CMV DNA in the blood of kidney recipients and can be useful in monitoring the efficacy of anti-CMV therapy.
Madi
Nada
N
WHO Collaborative Centre for Virus Reference and Research and for Immunodeficiency Syndrome for EMR, Virology Unit, Department of Microbiology, Faculty of Medicine, Kuwait University, Kuwait. madi@hsc.edu.kw
Al-Nakib
Widad
W
Mustafa
Abu Salim
AS
Saeed
Tarek
T
Pacsa
Alexander
A
Nampoory
M R Narayanan
MR
D000328:Adult; D003586:Cytomegalovirus Infections / Q000175:diagnosis* / Q000235:genetics*; D004279:DNA, Viral / Q000097:blood; D005260:Female; D006801:Humans; D016030:Kidney Transplantation; D008297:Male; D010750:Phosphoproteins / Q000097:blood; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D019562:Viral Load; D014763:Viral Matrix Proteins / Q000097:blood
D004279:DNA, Viral; D010750:Phosphoproteins; D014763:Viral Matrix Proteins; C065418:cytomegalovirus matrix protein 65kDa