Sepsis neonatorum

Neonatal infections are infections of the neonate (newborn) acquired during prenatal development or in the first four weeks of life (neonatal period). Neonatal infections may be contracted by mother to child transmission, in the birth canal during childbirth, or contracted after birth. Some neonatal infections are apparent soon after delivery, while others may develop in the postnatal period. Some neonatal infections such as HIV, hepatitis B, and malaria do not become apparent until much later. Neonatal infections are infections of the neonate (newborn) acquired during prenatal development or in the first four weeks of life (neonatal period). Neonatal infections may be contracted by mother to child transmission, in the birth canal during childbirth, or contracted after birth. Some neonatal infections are apparent soon after delivery, while others may develop in the postnatal period. Some neonatal infections such as HIV, hepatitis B, and malaria do not become apparent until much later. There is a higher risk of infection for preterm or low birth weight neonates. Infant respiratory distress syndrome is often a condition of preterm neonates that can have long-term negative consequences, it can also arise following an infection. In some instances, neonatal respiratory tract diseases may increase the susceptibility to future respiratory infections and inflammatory responses related to lung disease. Antibiotics can be effective for neonatal infections, especially when the pathogen is quickly identified. Instead of relying solely on culturing techniques, pathogen identification has improved substantially with advancing technology; however, neonate mortality reduction has not kept pace and remains 20% to 50%. While preterm neonates are at a particularly high risk, all neonates can develop infection. Neonatal infection may also be associated with premature rupture of membranes (breakage of the amniotic sac) which substantially increases the risk of neonatal sepsis by allowing passage for bacteria to enter the womb prior to the birth of the infant. Neonatal infection can be distressing to the family and it initiates concentrated effort to treat it by clinicians. Research to improve treatment of infections and prophylactic treatment of the mother to avoid infections of the infant is ongoing. In industrialized countries, treatment for neonatal infections takes place in the neonatal intensive care unit (NICU). The causes and reasons for neonatal infection are many. The origin of infectious bacteria and some other pathogens is often the maternal gastrointestinal and genitourinary tract. Many of the maternal infections with these organisms are asymptomatic in the mother. Other maternal infections that may be transmitted to the infant in utero or during birth are bacterial and viral sexually transmitted infections. The infant's ability to resist infection is limited by its immature immune system. The causative agents of neonatal infection are bacteria, viruses, and fungi. In addition, the immune system of the neonate may respond in ways that can create problems that complicate treatment, such as the release of inflammatory chemicals. Congenital defects of the immune system also affect the infants ability to fight off the infection. Group B streptococcus are typically identified as the cause of the majority of early-onset infections in the neonate.This pathogen is vertically transmitted (transmitted directly from the mother) to the infant. Enteric bacilli that originate from the digestive system of the mother have become as prevalent as the group B streptococcus pathogens and are currently as likely to cause infection. With the advances in preventing group B streptococcus infections, β-lactam-resistant Escherichia coli infections have increased in causing neonatal deaths in very low birthweight and premature infants. Infections with Staphylococcus aureus are also diagnosed, but not as frequently as group B streptococcus infections. Listeria monocytogenes can also cause infection acquired from tainted food and present in the mother. The presence of this pathogen can sometimes be determined by the symptoms that appear as a gastrointestinal illness in the mother. The mother acquires infection from ingesting food that contains animal products such as hot dogs, unpasteurized milk, delicatessen meats, and cheese. Neonatal infection can also occur in term and post-term infants. Infections that develop one month after the birth of the infant are more likely due to Gram-positive bacteria and coagulase positive staphylococci.Acquired maternal infection and subsequent inflammation from Ureaplasma urealyticum is accompanied by a strong immune response and is correlated with the need for prolonged mechanical ventilation. Clostridium tetani can cause a generalised form of tetanus in the neonate. This usually occurs when the mother has not been vaccinated against tetanus and the baby has not acquired passive immunity. The umbilical cord region is the most susceptible. Other bacterial pathogens include Streptococcus agalactiae, Streptococcus pyogenes, Viridans streptococci, Streptococcus pneumoniae, Haemophilus influenzae, and Pseudomonas aeruginosa.