Comprehensive Overview of Early-Onset Neonatal Sepsis (EONS)

Recap of Early-Onset Neonatal Sepsis (EONS)

Category	Concept
Definition	Sepsis within the first 72 hours of life.
Maternal Risk Factors	Prolonged rupture of membranes, maternal fever, UTI or chorioamnionitis, GBS colonization, premature delivery.
Clinical Signs in Neonate	Respiratory distress, temperature instability, feeding intolerance, lethargy, hypotonia, poor perfusion, apnea, cyanosis, tachycardia.
Laboratory Findings	Positive blood culture, abnormal CSF analysis, abnormal CBC, elevated CRP or procalcitonin.
Triple I Criteria	Maternal fever, elevated maternal WBC, foul-smelling amniotic fluid, uterine tenderness, maternal and fetal tachycardia.
Associated TORCH Infections	Toxoplasmosis, syphilis, varicella-zoster, mumps, parvovirus B19, rubella, CMV, HSV.
Clinical Presentation of TORCH Infections	Growth retardation, jaundice, hepatosplenomegaly, fever, skin rashes, microcephaly, hearing loss, eye abnormalities.

Introduction: Early-onset neonatal Sepsis (EONS) is a serious and life-threatening condition that occurs within the first 72 hours of a newborn's life. It requires immediate medical attention and intervention to improve outcomes and reduce mortality rates. This blog post aims to provide an in-depth understanding of EONS, covering maternal risk factors, clinical signs in neonates, laboratory findings, and associated infections.

Maternal Risk Factors for EONS:

• Prolonged Rupture of Membranes (PROM):

  • Definition: When the amniotic sac ruptures more than 18 hours before delivery.

  • Importance: Prolonged exposure increases the risk of bacterial infection in the neonate.

• Maternal Fever:

  • Criteria:

  • ≥38°C (100.4°F) on two separate occasions at least one hour apart.

  • A single occurrence of fever ≥39°C (102.2°F).

  • Significance: Indicates potential infection that could be transmitted to the neonate.

• Maternal Urinary Tract Infection (UTI) or Chorioamnionitis:

  • UTI: Infection in the urinary tract can ascend and affect the amniotic fluid and fetus.

  • Chorioamnionitis: Infection of the amniotic fluid, membranes, placenta, and/or uterus.

• Maternal Group B Streptococcus (GBS) Colonization:

  • Without adequate intrapartum antibiotic prophylaxis, GBS can be transmitted to the neonate during delivery.

• Premature Delivery:

  • Especially deliveries before 37 weeks of gestation.

  • Premature infants have underdeveloped immune systems, making them more susceptible to infections.
    

Clinical Signs in the Neonate:

• Respiratory Distress:

  • Symptoms: Grunting, nasal flaring, retractions (pulling in of the chest wall), and rapid breathing (tachypnea).

  • Importance: Indicates possible lung infection or inflammation.

• Temperature Instability:

  • Symptoms: Hypothermia (low body temperature) or hyperthermia (high body temperature).

  • Importance: Neonates typically maintain stable body temperatures; fluctuations suggest infection.

• Feeding Intolerance:

  • Symptoms: Vomiting, abdominal distension, and poor feeding.

  • Importance: Indicates gastrointestinal involvement or systemic infection.

• Lethargy or Irritability:

  • Symptoms: Excessive sleepiness, unresponsiveness, or excessive crying.

  • Importance: Suggests central nervous system involvement.

• Hypotonia or Reduced Activity:

  • Symptoms: Decreased muscle tone and reduced spontaneous movements.

  • Importance: Indicates potential systemic infection affecting muscle function.

• Poor Perfusion or Circulatory Collapse:

  • Symptoms: Pale or mottled skin, delayed capillary refill time.

  • Importance: Indicates poor blood flow and oxygen delivery to tissues.

• Apnea or Bradycardia:

  • Symptoms: Episodes of stopped breathing (apnea) or slow heart rate (bradycardia).

  • Importance: Severe signs of systemic infection affecting respiratory and cardiac function.

• Cyanosis or Pallor:

  • Symptoms: Bluish discoloration of the skin (cyanosis) or pale appearance (pallor).

  • Importance: Indicates inadequate oxygenation or severe infection.

• Tachycardia:

  • Symptom: Increased heart rate.

  • Importance: Body’s response to infection or stress.
    

Laboratory Findings:

• Positive Blood Culture:

  • Confirms the presence of pathogenic bacteria in the bloodstream.

• Cerebrospinal Fluid (CSF) Analysis:

  • Pleocytosis: Increased white blood cells in CSF.

  • Elevated protein levels.

  • Decreased glucose levels.

  • Importance: Indicates meningitis or central nervous system infection.

• Abnormal Complete Blood Count (CBC) with Differential:

  • Leukocytosis: Increased white blood cells.

  • Leukopenia: Decreased white blood cells.

  • Increased Immature-to-Total Neutrophil Ratio (I ratio).

  • Importance: Reflects the body’s immune response to infection.

• Elevated C-Reactive Protein (CRP) or Procalcitonin Levels:

  • Markers of inflammation and infection.

  • Importance: Helps in the early identification of sepsis.
    

Triple I Criteria (Intrauterine Inflammation or Infection or both):

1. Maternal Fever: As previously defined.

2. Elevated Maternal White Blood Cell (WBC) Count: >15,000 cells/mm³.

3. Foul-Smelling Amniotic Fluid: Indicative of infection.

4. Uterine Tenderness: Suggests infection or inflammation.

5. Maternal Tachycardia: Increased heart rate in the mother.

6. Fetal Tachycardia: Increased heart rate in the fetus.
   

Associated Infections (TORCH):

• Toxoplasmosis

• Other Infections:

  • Examples: Syphilis, varicella-zoster, mumps, parvovirus B19.

• Rubella

• Cytomegalovirus (CMV)

• Herpes Simplex Virus (HSV)
  

Clinical Presentation of TORCH Infections:

• Growth Retardation:

  • Poor intrauterine growth leading to low birth weight.

• Jaundice:

  • Yellowing of the skin and eyes due to elevated bilirubin levels.

• Hepatosplenomegaly:

  • Enlarged liver and spleen.

• Fever:

  • Elevated body temperature.

• Skin Rashes or Vesicles:

  • Various types of rashes or blister-like lesions.

• Microcephaly:

  • Smaller than normal head size, indicating potential brain development issues.

• Hearing Loss:

  • Due to nerve damage or structural anomalies.

• Eye Abnormalities:

  • Cataracts, and chorioretinitis (inflammation of the retina), among others.
    

Conclusion: Early onset Neonatal Sepsis (EONS) requires prompt and comprehensive medical intervention. By understanding the maternal risk factors, recognizing clinical signs in neonates, and utilizing appropriate laboratory tests, healthcare professionals can diagnose and manage EONS effectively. Awareness and management of associated TORCH infections further improve neonatal outcomes, ensuring timely and appropriate care for affected newborns.

This detailed blog post is designed to be informative and accessible, providing healthcare professionals and medical students with a comprehensive understanding of Early-Onset Neonatal Sepsis (EONS).