Diagnostic value of Cytomegalovirus DNA real-time quantitative-polymerase chain reaction in different body fluids for Cytomegalovirus pneumonia in immunocompetent infants / 中华实用儿科临床杂志

ABSTRACT

Objective@#To investigate the value of Cytomegalovirus(CMV) DNA real-time quantitative-polymerase chain reaction(RT-PCR) in different body fluids for diagnosing CMV pneumonia in immunocompetent infants.@*Methods@#The clinical data of immunocompetent infants with CMV pneumonia who were treated in Pediatric Intensive Care Unit of Guangdong Women and Children′s Hospital from January 1st, 2016 to February 5th, 2018 were retrospectively analyzed.The clinical data included CMV DNA load of bronchoalveolar lavage fluid(BALF), urine, blood and cerebrospinal fluid(CSF); blood immunoglobulin(Ig)M CMV, alanine aminotransferase (ALT), X-ray and CT test of chest, combined infection, clinical manifestation and treatment.@*Results@#Nine hundred and twenty-six infants received bronchoalveolar lavage by bronchoscope, and 34 cases were diagnosed as immunocompetent with CMV pneumonia.The infants with CMV pneumonia the positive percentage of urine CMV DNA, blood CMV DNA, blood IgM CMV and ALT elevation were 100.0%(34/34 cases), 61.8%(21/34 cases), 52.9%(18/34 cases) and 20.6%(7/34 cases), respectively.There was no difference in positive percentage between blood CMV DNA and blood IgM CMV (χ2=0.5, P>0.05). Both the positive percentages of blood CMV DNA and blood IgM CMV were lower than those in the urine CMV DNA, and the differences were statistically significant (χ2=16.1, 20.9, all P<0.05). The positive percentages of ALT elevation were lower than those in the positive percentage of urine CMV DNA, blood CMV DNA and blood IgM CMV, and the differences were statistically significant (χ2=44.8, 11.9, 7.7, all P<0.05). Ten patients′ CSF CMV DNA were tested, and they were all negative.The median load of CMV DNA in BALF, urine and blood was 170.0×105 copies/L, 130.0×105 copies/L and 6.0×105 copies/L.There was no difference in median load between BALF and urine (U=561, P>0.05). BALF CMV DNA load and blood CMV DNA load had a weak positive correlation (r=0.35, P<0.05), BALF CMV DNA load and age had a negative correlation (r=-0.42, P<0.05), and urine CMV DNA load and blood CMV DNA load had a positive correlation (r=0.52, P<0.05). No matter whether blood IgM CMV was positive, BALF CMV DNA load had no differences (U=92, P>0.05). The main radiographic signs were pulmonary interstitial lesions.Thirty-four immunocompetent infants with CMV pneumonia, 18 patients (52.9%) with symptoms lasted for over 2 weeks, 20 patients (58.8%) had complicated infections.They all received inductive treatment of Ganciclovir, 55.9%(19/34 cases) patients′ urine CMV DNA turned to be negative.When patients got combined infections by bacteria or mycoplasma, antibiotics were used.All discharged patients had symptoms relieved and signs improved.@*Conclusions@#BALF RT-PCR is instant, sensitive and distinctive method to diagnose CMV pneumonia.Urine RT-PCR gets specimens conveniently and safely, its positive percentage and DNA load are present well according to BALF, and is suitable for screening and monitoring CMV infection.Blood CMV DNA load and blood IgM CMV indicate viral dissemination and immunocompetence, but it is not recommended for diagnosing CMV pneumonia solely.