Group B streptococcal septicemia of the newborn

Definition

Group B streptococcal septicemia is a severe bacterial infection that affects newborn infants.

See also: Neonatal sepsis

Causes

Group B streptococcal septicemia is caused by the bacteria Streptococcus agalactiae. This bacteria is commonly found in the human gastrointestinal, reproductive, and urinary tracts.

If the bacteria travels from the mother's bloodstream through the placenta the infant can become infected. The infant may also become infected if the mother's water breaks (membranes rupture) as the infant passes through the birth canal.

The infant may also become infected after delivery.

The disease may be seen from birth to 6 days of life (generally in the first 24 hours) or in children age 7 days to 3 months. Most cases occur in babies around 1 month old.

Group B streptococcus was once responsible for about 75% of sepsis infections in infants. However, the rate of this condition has dropped since methods to screen and treat pregnant women at risk have been established.

The following increase an infant's risk for group B streptococcal septicemia:

• Mother who has a fever during labor
• Mother who has group B streptococcus in her gastrointestinal, reproductive, or urinary tracts
• Rupture of membranes ("water breaks") more than 18 hours before baby is delivered
• Prematurity
• Prior history of giving birth to a baby with this condition

Symptoms

Parents should watch for any of the following symptoms when their child is less than 3 months old, particularly in the first 6 weeks. The early stages of the disease can produce subtle symptoms.

Symptoms in the infant may include:

• Anxiety or stress
• Blue appearance (cyanosis)
• Breathing difficulties such as:
  • Grunting
  • Flaring of the nostrils
  • Rapid breathing
  • Short periods without breathing
• Coma
• Irregular heart rate - may be fast or extremely slow
• Irregular heartbeat
• Lethargy
• Poor feeding
• Shock
• Unstable body temperature (low or high)

Exams and Tests

Tests that may be done to diagnose this condition in a newborn include:

• Blood clotting tests - Prothrombin time (PT) and Partial thromboplastin time (PTT)
• Blood culture
• Blood gases
• Complete blood count
• CSF culture
• Urine culture
• X-ray of the chest

Treatment

Treatment may involve one or more of the following:

• Antibiotics given through a vein
• Fluids given through a vein
• Medicines to reverse shock
• Medicines or procedures to correct blood clotting problems
• Oxygen therapy
• Breathing help

A complex therapy called extra-corporeal membrane oxygenation (ECMO) may be used in very severe cases.

Outlook (Prognosis)

This disease can be deadly without early treatment.

Possible Complications

Possible complications include:

• Disseminated intravascular coagulation (DIC) -- a serious disorder in which the proteins that control blood clotting are abnormally active
• Hypoglycemia -- low blood sugar
• Meningitis -- an infection that causes inflammation of the membranes covering the brain and spinal cord
• Respiratory distress -- breathing stops

When to Contact a Medical Professional

This disease is usually diagnosed shortly after birth, often while the baby is still in the hospital. However, if you have a newborn at home who shows signs of this condition, seek immediate emergency medical help or call the local emergency number (such as 911).

Prevention

The American Academy of Pediatrics, American College of Obstetricians and Gynecologists, and the U.S. Centers for Disease Control and Prevention have established two methods to help reduce the risk of Group B streptococcal septicemia.

• Pregnant women are tested for group B streptococcus at 35 to 37 weeks of pregnancy. If the bacteria is detected, the woman is given antibiotics through an vein during labor.
• Prenatal screening is not done, but a woman who meets certain risk factors is given antibiotics through a vein during labor.

Both sets of procedures are currently accepted as the standard of care. In all cases, proper hand washing by nursery caretakers, visitors, and parents helps prevent the spread of the bacteria after the infant is born.

An early diagnosis can help decrease the risk of some complications.

Mandell GL, Bennett JE, Dolin R. Principles and Practice of Infectious Diseases. 6th ed. London: Churchill Livingstone; 2005.

Schrag S, Gorwitz R, Fultz-Butts K, Schuchat A. Prevention of perinatal group B streptococcal disease. Morbidity and Mortality Weekly Report. 51(RR-11): 1–22, 2002.

Schrag S. Prevention of neonatal sepsis. Clin Perinatol. Sept 2005; 32(3): 601-15.