Selección de un probiótico para la erradicación de streptococcus agalactiae durante el embarazo

Laburpena

Neonatal sepsis contributes substantially to neonatal morbidity and mortality, andis a major global public health challenge worldwide. According to the age of onset,neonatal sepsis is divided into early-onset sepsis (EOS) and late-onset sepsis (LOS).EOS has been variably defined based on the age at onset, with bacteremia or bacterialmeningitis occurring at ≤72 h in infants hospitalized in the neonatal intensive care unitversus <7 days in term infants. EOS reflects transplacental or ascending infections fromthe maternal genitourinary tract, whereas LOS is associated with the postnatalnosocomial or community environments, with a peak incidence reported to be betweendays 10 and 22 after birth.Streptococcus agalactiae (Group B Streptococci, GBS) is one of themicroorganisms most frequently involved in severe neonatal EOS cases. Women, menand children of all ages can be asymptomatically colonized with GBS, acting thegastrointestinal tract, vagina and urethra as reservoirs. The maternal colonization rateusually ranges from 12 to 28%. Recto-vaginal GBS screening at week 35-38 ofpregnancy, and subsequent intrapartum antibiotic prophylaxis (IAP) to positive mothers,is the most common strategy used to prevent neonatal GBS neonatal infections.However, such strategy does not prevent GBS-related abortions, stillbirths and pretermbirths, may lead to increasing rates of antibiotic resistance among clinically relevantmicroorganisms, and has a very negative impact on the acquisition, composition anddevelopment of the infant microbiota. GBS vaccines are not available at present and,therefore, there is a need for alternative strategies to avoid GBS colonization duringpregnancy. In this context, the general objective of this PhD Thesis was the selection ofa safe probiotic strain with the ability to eradicate GBS from the intestinal andgenitourinary tracts of pregnant women...