Identification of respiratory virus in infants with congenital heart disease by comparison of different methods.

Respiratory virus infections are the main cause of infant hospitalization and are potentially severe in children with congenital heart disease (CHD). Rapid and sensitive diagnosis is very important to early introduction of antiviral treatment and implementation of precautions to control transmission, reducing the risk of nosocomial infections. In the present study we compare different techniques in the diagnosis of respiratory viruses in CHD infants. Thirty-nine samples of nasopharyngeal aspirate were obtained from CHD infants with symptoms of respiratory infection. The Multiplex PCR (Seeplex® RV 12 ACE Detection) driven to the detection of 12 respiratory viruses was compared with the direct immunofluorescence assay (DFA) and PCR, both targeting seven respiratory viruses. The positivity found by DFA, Multiplex and PCR was 33.3%, 51.3% and 48.7%, respectively. Kappa index comparing DFA and Multiplex, DFA and PCR and PCR and Multiplex PCR was 0.542, 0.483 and 0.539, respectively. The concordance between techniques was considered moderate. Both Multiplex PCR (p = 0.001) and PCR (p = 0.002) detected significantly more respiratory virus than DFA. As the performance of the tests may vary, the combination of two or more techniques may increase diagnostic sensitivity favoring the diagnosis of co-infections, early introduction of antiviral therapy and implementation of appropriate measures.

Identification of respiratory virus in infants with congenital heart disease by comparison of different methods / Identificação de vírus respiratórios em crianças com cardiopatia congênita por comparação de diferentes métodos

Respiratory virus infections are the main cause of infant hospitalization and are potentially severe in children with congenital heart disease (CHD). Rapid and sensitive diagnosis is very important to early introduction of antiviral treatment and implementation of precautions to control transmission, reducing the risk of nosocomial infections. In the present study we compare different techniques in the diagnosis of respiratory viruses in CHD infants. Thirty-nine samples of nasopharyngeal aspirate were obtained from CHD infants with symptoms of respiratory infection. The Multiplex PCR (Seeplex® RV 12 ACE Detection) driven to the detection of 12 respiratory viruses was compared with the direct immunofluorescence assay (DFA) and PCR, both targeting seven respiratory viruses. The positivity found by DFA, Multiplex and PCR was 33.3 percent, 51.3 percent and 48.7 percent, respectively. Kappa index comparing DFA and Multiplex, DFA and PCR and PCR and Multiplex PCR was 0.542, 0.483 and 0.539, respectively. The concordance between techniques was considered moderate. Both Multiplex PCR (p = 0.001) and PCR (p = 0.002) detected significantly more respiratory virus than DFA. As the performance of the tests may vary, the combination of two or more techniques may increase diagnostic sensitivity favoring the diagnosis of co-infections, early introduction of antiviral therapy and implementation of appropriate measures.

Infecções respiratórias virais são a principal causa de hospitalização infantil e podem ser extremamente graves em crianças com cardiopatia congênita. O diagnóstico rápido e sensível é importante para a introdução precoce de tratamento antiviral e implantação de precauções para controle da transmissão, reduzindo o risco de infecções nosocomiais. Neste estudo, comparamos o desempenho de diferentes técnicas no diagnóstico de vírus respiratórios em crianças com cardiopatia congênita e sintomas respiratórios. Trinta e nove amostras de aspirado de nasofaringe foram obtidas de crianças com sintomas de infecção respiratória. Ensaio de PCR Multiplex que detecta 12 vírus respiratórios (Seeplex® RV 12 ACE Detection) foi comparado à Imunofluorescência Direta (IFD) e à PCR específica, ambas direcionadas a sete vírus. A positividade da IFD foi 33,3 por cento, do Multiplex foi 51,3 por cento e da PCR 48,7 por cento. O índice kappa comparando IFD e Multiplex, IFD e PCR, e PCR e Multiplex foi, respectivamente, 0,542, 0,483 e 0,539, sendo a concordância considerada moderada. O Multiplex e a PCR detectaram significantemente mais vírus que a IFD (p < 0,0001 e 0,002, respectivamente). Como o desempenho dos testes varia o uso de mais de uma técnica pode aumentar a sensibilidade diagnóstica favorecendo a introdução precoce de terapia antiviral e implantação de medidas profiláticas.