Neonatal Sepsis
Neonatal sepsis is defined as a positive blood culture during the first 28 days of life. Infection is most commonly caused by organisms present in the birth canal, though it may also be acquired by the transplacental route or from an environmental pathogen following birth. The most common organisms are group B beta-hemolytic streptococci, and E. coli. Other enteric bacteria, Listeria and Staphylococcus aureus may also be implicated. Premature babies are also at risk for infection with coagulase negative staphylococci and Candida.
The physician should be especially alert to the possibility of neonatal sepsis when the maternal history indicates cervical colonization with potentially infectious organisms such as group B streptococci, prolonged rupture of the membranes, or chorioamnionitis.
The signs and symptoms of neonatal sepsis may be subtle. The baby may just be "not doing well", or may exhibit fever, hypothermia, poor feeding, jaundice, abdominal distention, vomiting, apnea, irritability, or pallor or mottling.
Cultures must be obtained of blood, urine (by steile catheterization or suprapubic aspiration) and cerebrospinal fluid. A positive culture confirms the diagnosis of sepsis, but the negative culture does not necessarily exclude it.
Because meningitis occurs in a significant proportion of septic neonates, the cerebrospinal fluid should also be sent for cell count, Gram stain, culture and protein and glucose determination. CBC and chest x-ray are generally also obtained and may provide a clue to the presence or site of infection.
Treatment must be initiated as soon as sepsis is suspected, even before results of cultures and diagnostic studies have been determined. Initial therapy should include broad-spectrum antibiotic coverage. A combination of ampicillin and gentamicin is the usual initial regimen. Once the organism and its antibiotic sensitivity pattern have been identified, the single most effective antibiotic should be continued for 7 to 10 days. Meningitis needs to be treated for two to three weeks.
