Neonatal Sepsis and Permanent Outcomes

Neonatal sepsis is an infection in the bloodstream that poses severe health risks to newborns, including permanent brain damage. It can be caused by a variety of bacteria, viruses, and other pathogens. A baby can acquire neonatal sepsis through either vertical or horizontal transmission. In vertical transmission, a maternal infection is spread to the baby shortly before or during the birthing process. In horizontal transmission, the baby acquires an infection after birth, from contact with caregivers, medical personnel, or environmental contaminants.

Medical professionals can often prevent neonatal sepsis by properly treating expectant mothers who have infections and ensuring that the hospital environment is clean. Additionally, because neonatal sepsis is so dangerous, the threshold for treatment is fairly low. Infants with suspected sepsis should receive antibiotics while awaiting laboratory results (1).

Failure to properly prevent and/or treat neonatal sepsis is negligence, and if this negligence causes harm, it constitutes medical malpractice.

A “birth injury” is any type of harm to a baby that occurs shortly before birth, during birth, or in early infancy. Neonatal infections, such as sepsis, are included. Sepsis can cause the following complications, health conditions, and disabilities, among others (1, 2):

• Septic shock (dangerously low blood pressure)
• Neonatal seizures
• Apnea/bradycardia
• Respiratory distress (which may be difficult to distinguish from respiratory distress syndrome)
• Feeding issues
• Meningitis (infection around the brain and spinal cord)
• Encephalitis (inflammation of the brain that can lead to lifelong disabilities such as hypoxic-ischemic encephalopathy, cerebral palsy, and epilepsy)

The most common causes of neonatal sepsis are Group B Streptococcus (GBS) and Escherichia coli (E. coli) bacteria. Other types of infection that may lead to neonatal sepsis include the following (1):

Bacterial agents:

• Listeria monocytogenes
• Staphylococcus aureus
• Enterococcus
• Other gram-negative bacteria such as Klebsiella and Enterobacter
• Coagulase-negative staphylococci (CoNS)

Non-bacterial agents

• Herpes simplex virus (HSV)
• Enterovirus and parechovirus
• Candida

Early-onset sepsis (either before seven days of age or in the first 72 hours of life; exact definitions vary) is usually associated with vertical transmission. This means the infant likely acquired the infection just before or during the birthing process. In some cases, infection ascends the mother’s birth canal (1); the risk of this is higher if the mother has experienced premature rupture of membranes (PROM) (3). The infant may also contract a lower genital tract infection during vaginal delivery. Late-onset sepsis (after seven days or 72 hours, depending on which definition you follow), can be acquired either vertically (sometimes early colonization takes awhile to evolve into a serious infection) or horizontally (1).

Risk factors for vertically-transmitted neonatal sepsis include the following (1):

• Premature rupture of membranes (PROM)
• Chorioamnionitis (infection of the placenta and fetal membranes)
• Group B Strep (this is routinely tested for during pregnancy) or another infection in the mother
• The mother has a high temperature during birth
• Preterm birth
• Use of forceps during delivery
• Use of electrodes for intrauterine monitoring
• Hospital stay: Newborns who have long hospital stays and/or extended catheterization are at higher risk of acquiring sepsis due to a horizontally-transmitted infection (4). Unsanitary hospital conditions can also increase the risk.

Signs and symptoms of neonatal sepsis include the following (1, 4):

Prior to/during birth:

• Fetal tachycardia (an abnormally fast heart rate) and other signs of fetal distress
• Meconium-stained amniotic fluid

In a newborn:

• Low Apgar score (six or below)
• Temperature control issues (term infants are more likely to have a fever, while preterm infants are more likely to have hypothermia)
• Lethargy or irritability
• Respiratory issues such as tachypnea and apnea
• Tachycardia or bradycardia
• Hypotension (low blood pressure)
• Perfusion problems
• Hypotonia (low muscle tone/floppiness)
• Feeding issues
• Seizures
• Jaundice
• Hepatomegaly (liver enlargement)
• Vomiting
• Diarrhea or low frequency of bowel movements
• Distention of the abdomen
• Hypoglycemia (low blood sugar)

The definitive diagnosis of neonatal sepsis involves testing the baby’s blood to look for the presence of bacteria or other pathogens.  Getting a positive blood culture can take a long time, and some tests may produce false-negative results, meaning that the test shows no evidence of sepsis when the baby actually does have the infection.  Because of this, it is very important for doctors to do clinical assessments and other tests to determine a baby’s likelihood of having sepsis. If a baby is at risk, treatment must be initiated immediately, and doctors should continue to perform blood tests and other evaluations.

In addition to looking for the potential signs and symptoms of sepsis listed above, medical professionals may perform the following exams and tests (1, 4):

• Blood tests:
  • Cultures
  • C-reactive protein (CRP) and/or procalcitonin (PCT) levels
  • Complete blood count (CBC)
• Lumbar puncture (spinal tap)
• Chest x-ray
• Urine or stool culture tests
• Cultures from other potential areas of infection (e.g. tracheal aspirates, pustules, or eye drainage)

It is very important that medical professionals do all they can to prevent neonatal sepsis. This entails properly screening expectant mothers for Group B Strep, as well as any other infections they are at risk of contracting or may have already contracted. Mothers who have infections should be given treatment to reduce the risk of transmission to their infant. Maternal intrapartum antibiotic prophylaxis (IAP) can reduce the risk of GBS vertical transmission, but it does not completely eliminate it – therefore, doctors and nurses should still carefully assess the baby’s health.

It is critical that expectant mothers be given a clean place to deliver their baby, so that infections do not ascend the genital tract during birth (1). Additionally, doctors should be aware of how long it has been since a woman’s membranes ruptured. Too long an interval between membrane rupture and birth can increase the risk of infection; in some cases, a C-section delivery may be necessary (3).

To prevent horizontally-transmitted infections (i.e. infections acquired after birth), newborns should be kept in a clean environment. Newborns have relatively weak immune systems, especially if born prematurely, and are vulnerable to infection.

Since neonatal sepsis is a major threat to infant health, treatment can and should be given before diagnosis is confirmed. Infants with suspected sepsis should be given antibiotics because most cases are bacterial (1). The duration of the antibiotic course will vary depending on whether bacteria are found in the blood or spinal fluid. If no bacteria are found, treatment will be shorter. If doctors determine that a baby has sepsis, but it was caused by a non-bacterial pathogen, different treatment may be necessary. For example, babies that have contracted HSV should be given an antiviral medication (4).

If given prompt and proper treatment, babies with neonatal sepsis will likely recover with no lasting health issues (4). However, there are several very serious birth injuries/complications that may result from neonatal sepsis. These issues are more likely to arise when sepsis goes undiagnosed or is improperly treated (2):

• Infant death: in term and late preterm infants, the rate of mortality from neonatal sepsis has been estimated at around two to four percent (5)
• Meningitis
• Developmental delays
• Cerebral palsy
• Seizure disorders
• Hearing loss