Estudio retrospectivo de factores de riesgo de transmisión vertical de infección por virus hepatitis C / Retrospective study of risk factors of vertical transmission of hepatitis C virus

Introducción: A pesar de la baja prevalencia infantil de infección por virus hepatitis C (VHC) y su leve clínica inicial, la infección crónica puede evolucionar a cirrosis y/o hepatocarcinoma. Es fundamental controlar su transmisión vertical. Los últimos estudios describen hasta 50% de transmisiones intraútero. Material y métodos: Estudiamos retrospectivamente 17 casos de infección por VHC en 8 años, analizando los factores de riesgo de transmisión vertical, para aplicar prevención primaria. Resultados: Solo la adicción a drogas vía parenteral muestra riesgo significativo, sin ser la coinfección VIH factor de confusión. La carga viral, la coinfección por VIH, la disfunción hepática y el tiempo de evolución de infección no muestran mayor riesgo. La cesárea, la amniocentesis y la monitorización interna pueden ser factores de riesgo (sin significación estadística), pero no las horas de amniorrexis. La lactancia materna muestra protección. Conclusiones: Pese a la importancia frecuentemente atribuida, el efecto de la carga viral sobre el riesgo de transmisión no está claramente establecido: la ausencia de viremia no descarta el riesgo de transmisión, ya que la detección de ARN viral puede ser intermitente, y por tanto, los datos al respecto deben interpretarse con cautela. La inmunosupresión secundaria a la coinfección por VIH supone mayor riesgo de transmisión, pero dicho efecto disminuye al mejorar la capacidad inmune gracias al tratamiento antirretroviral. Respecto a las características del parto, el tiempo transcurrido tras la rotura de membranas no ha mostrado ser factor de riesgo; y se desestima la cesárea como forma óptima y electiva de finalizar la gestación de estas mujeres. La lactancia materna, lejos de suponer mayor riesgo de transmisión, puede ser protectora. La escasa carga viral en la leche, su inactivación por el pH ácido gástrico y sus beneficios inmunológicos justificarían este resultado. Dadas las limitaciones de los estudios retrospectivos, es necesario plantear análisis prospectivos para conocer mejor el papel de los posibles factores de riesgo y establecer pautas claras de prevención; de momento, es fundamental el control evolutivo de todos los hijos de madres con infección por el VHC (AU)

Introduction: Despite the low prevalence of paediatric HCV infection and its initial mild clinical expressiveness, chronic infection could progress into cirrhosis and/or hepatocarcinoma. It is essential to control vertical transmission. Recent studies show that up to 50% of transmissions occur within the uterus. Material y methods: A retrospective study was conducted on 17 cases of (Hepatitis C virus) HCV infection registered over a period of 8 years. Vertical transmission risk factors were analysed, in order to introduce primary prevention. Results: Only parenteral drug addiction significantly increased the rate of HCV transmission; HIV co-infection was not a confounding factor. HCV viremia, HIV co-infection, liver dysfunction and/or duration of the infection did not appear to affect the rate of transmission. Caesarean section, amniocentesis and internal monitoring may be risk factors (not statistically significant), but not prolonged vaginal delivery after amniotic membrane rupture. Breastfeeding showed protection. Conclusions: The effect of viremia on the risk of transmission is not clearly established, despite the importance usually attributed. Lack of viremia does not discount the risk of transmission, due to viral RNA detection can be intermittent, so it should be interpreted cautiously. Immunosuppression secondary to HIV co-infection implies a higher risk of transmission, but this effect decreases by improving immune competence by antiretroviral treatment. With regard to the birth characteristics, time after the rupture of membranes has not shown being a risk factor; being the caesarean not advisable as a good alternative to finish the pregnancy. Breastfeeding does not increase the risk, even it can be protective. This results would be justified by the low viral content of milk, its inactivation by gastric pH and its immunological benefits. Given that retrospective studies results are limited, prospective studies need to be carried out in order to improve the understanding of the role of possible risk factors and to provide a clear preventive guidelines. At the moment it is essential to control all the children born of mothers with HCV infection (AU)

[Retrospective study of risk factors of vertical transmission of hepatitis C virus]. / Estudio retrospectivo de factores de riesgo de transmisión vertical de infección por virus hepatitis C.

INTRODUCTION: Despite the low prevalence of paediatric HCV infection and its initial mild clinical expressiveness, chronic infection could progress into cirrhosis and/or hepatocarcinoma. It is essential to control vertical transmission. Recent studies show that up to 50% of transmissions occur within the uterus. MATERIAL AND METHODS: [corrected] A retrospective study was conducted on 17 cases of (Hepatitis C virus) HCV infection registered over a period of 8 years. Vertical transmission risk factors were analysed, in order to introduce primary prevention. RESULTS: Only parenteral drug addiction significantly increased the rate of HCV transmission; HIV co-infection was not a confounding factor. HCV viremia, HIV co-infection, liver dysfunction and/or duration of the infection did not appear to affect the rate of transmission. Caesarean section, amniocentesis and internal monitoring may be risk factors (not statistically significant), but not prolonged vaginal delivery after amniotic membrane rupture. Breastfeeding showed protection. CONCLUSIONS: The effect of viremia on the risk of transmission is not clearly established, despite the importance usually attributed. Lack of viremia does not discount the risk of transmission, due to viral RNA detection can be intermittent, so it should be interpreted cautiously. Immunosuppression secondary to HIV co-infection implies a higher risk of transmission, but this effect decreases by improving immune competence by antiretroviral treatment. With regard to the birth characteristics, time after the rupture of membranes has not shown being a risk factor; being the caesarean not advisable as a good alternative to finish the pregnancy. Breastfeeding does not increase the risk, even it can be protective. This results would be justified by the low viral content of milk, its inactivation by gastric pH and its immunological benefits. Given that retrospective studies results are limited, prospective studies need to be carried out in order to improve the understanding of the role of possible risk factors and to provide a clear preventive guidelines. At the moment it is essential to control all the children born of mothers with HCV infection.