Use of PCR for prenatal and postnatal diagnosis of congenital rubella

Abstract

A reverse transcription-nested PCR assay (RT-PCR) was evaluated for diagnosis of congenitally acquired rubella in utero and during infancy. RT-PCR was compared with virus isolation for retrospective detection of rubella virus in placental and fetal tissues obtained after termination of pregnancy following primary rubella or rubella virus reinfection. Concordant results were obtained for 85% of samples; rubella virus RNA was detected by RT-PCR alone in four samples, and rubella virus was detected by isolation alone in two samples. Samples were also obtained for prenatal diagnosis of congenital infection; rubella virus RNA was detected in three of seven chorionic villus samples and one of three amniotic fluid samples by RT-PCR, while rubella virus was isolated in only one chorionic villus sample. To demonstrate that the RNA extracted from chorionic villus samples contained amplifiable RNA, a nested RT-PCR was used to detect keratin mRNA. Rubella virus was detected in the placenta in two cases in which the fetus was uninfected, and there was no evidence of rubella virus in the placenta from one case in which the fetus was infected. Thus, detection of rubella virus in chorionic villus samples by RT-PCR may not always correctly predict fetal rubella virus infection. RT-PCR was successfully used for the diagnosis of congenitally acquired rubella in infancy.Rubella virus RNA was detected in cyropreserved or formalin-fixed lens aspirates obtained from infants in India with serologically confirmed congenital rubella but not in samples from controls with inherited cataract.

Prenatal diagnosis of rubella virus infection by direct detection and semiquantitation of viral RNA in clinical samples by reverse transcription-PCR

“…In previous reports, CV was the most common specimen examined for the prenatal diagnosis of RV infection by molecular techniques (4,15,16). However, its limited utility for the prenatal diagnosis of rubella was shown by the lack of correlation between placental and fetal infection (4).…”

“…Recently, an RT-nPCR protocol for the diagnosis of RV infection has been reported (4,5). In those reports, the investigators achieved an excellent sensitivity with their technique (two viral GEs) and checked for the presence of possible RT-PCR inhibitors by amplifying keratin mRNA.…”

“…The tests currently used are virus isolation, determination of IgM antibodies against RV in fetal blood specimens (13,18), or direct detection of viral RNA by hybridization (16,20). Only a very few reports on the detection of RV RNA by reverse transcription-PCR (RT-PCR) have been published (5,7,10), and even fewer studies have addressed the use of RT-PCR for the prenatal diagnosis of congenital rubella (4,15).…”

Rubella and pregnancy: diagnosis, management and outcomes

“…In cases in which the RV-IgM test is positive, a congenital infection might be confirmed by isolating the rubella virus or by detecting the viral genome in nasopharyngeal swabs, urine and oral fluid using RT-PCR. 73 Performing a postnatal diagnosis of a congenital infection is important, regardless of whether a clinical manifestation of CRS is observed, to provide a specific follow-up care plan if an infection is discovered (including neurological and hearing monitoring). 47 A child infected in utero could excrete the virus in saliva and urine for several months or years.…”

Epidemiologia molecular do vírus da rubéola isolados no Estado de São Paulo durante o período de 1997 a 2004.

“…Não podemos esquecer que o isolamento viral em cultura de células continua sendo considerado o padrão ouro para a detecção de rubéola em amostras biologicas. A rubéola cresce um uma variedade de linhagens células, porém o crescimento viral é lento e o seu efeito citopático é de difícil visualização (Frey TK, 1994 Bosma et al (1995b), Revello et al (1997) e Andrade et al (2006) que estudaram casos de infecção materna. O diagnóstico clinico e laboratorial das infecções congênitas não é uma tarefa fácil, pois aproximadamente 50% das gestantes são assintomáticas.…”