Cytomegalovirus infection in children with Down syndrome in a day-care center in Brazil

Abstract

SUMMARYThis study evaluates the transmission of CMV infection in 120 children aged 1 to 15 years with Down syndrome who attended a day-care center for handicapped children in São Paulo, Brazil. A blood sample was obtained from each children at the beginning of the study for detection of IgG and IgM cytomegalovirus (CMV) antibodies by an immunofluorescence assay. Samples of saliva and urine were obtained every 3 months from the children with CMV antibodies to detect shedding of the virus by culture in human foreskin fibroblasts, by detection of pp65 CMV-antigen and by a nested PCR assay.The prevalence of anti CMV-IgG antibodies was 76.6% (92/120), and IgM anti-CMV antibodies were detected in 13% (12/92) of the seropositive children.During the first viral evaluation, CMV was detected in the urine and/or saliva in 39/90 (43.3%) of the seropositive children. In the second and third evaluations, CMV was detected in 41/89 (46%) and in 35/89 (39.3%) children, respectively. Detection of CMV was shown both in urine and saliva in 28/39 (71.8%), 19/41(46.3%) and 20/35 (57.1%) of the children excreting the virus, respectively. Additionally, in 33/49 (67.4%) of the excreters CMV could be demonstrated in urine or saliva in at least two out of the three virological evaluations carried out sequentially in a six month period.Of the 28 initially seronegative children, 26 were re-examined for anti-CMV IgG antibodies about 18 months after the negative sample; seroconversion was found in 10/26 (38.5%).Taking all 536 samples of urine or saliva examined by virus culture and pp65 antigen detection during the study into account, 159 (29.6%) were positive by virus culture and 59 (11%) gave a positive result with the pp65 assay.These data demonstrate the high prevalence of CMV shedding and the high risk of CMV infection in children with Down syndrome attending a day-care center for mentally handicapped patients. The virus culture was more sensitive than the pp65 CMV antigen assay for CMV detection in both urine and saliva samples.

Inflammatory and Immunological parameters in adults with Down syndrome

“…Some of the results are in line with the ones of other authors [26,27,17,18] and they may reflect an adaptive mechanism in adults with Down syndrome in order to sustain an efficient response…”

“…The response against vaccinal antigens and other antigens such as pertussis, rubella, measles, hepatitis A and B was better in DS patients when compared with other groups [10-14]. However other studies disagree with this affirmation [15-18]. …”

Differential detection of B virus and rhesus cytomegalovirus in rhesus macaques FN1

“…However, recent evidence has demonstrated that mucosal shedding of HCMV occurs commonly in many healthy individuals (do Canto et al, 2000;Lucht et al, 1998;Shen et al, 1996) and very frequently in immunocompromised patients (Diamond et al, 2000;Fidouh-Houhou et al, 2001;Lucht et al, 1998;Mostad et al, 2000). In this study, RhCMV shedding was detected consistently in many animals, indicating low-level, persistent infection.…”

Cytomegalovirus seroconversion rates and risk factors: implications for congenital CMV

“…Only two of these studies looked at seroconversion in children, finding seroconversion rates of 26% in children with Down syndrome in day care [19] and 4.3% in children enrolled from paediatric well child clinics where day-care attendance was found to be a risk factor for seroconversion [20].…”