Plasma alpha-fetoprotein in neonatal foals affected by prematurity, sepsis and neonatal encephalopathy.

The research article studies the diagnostic and predictive value of Alpha-fetoprotein (AFP) levels in newborn foals suffering from prematurity, sepsis, and neonatal encephalopathy. Though AFP is found in higher concentrations in these sick foals compared to healthy ones, the study suggests that it’s a non-specific health indicator and is unable to distinguish between varied diseases and outcomes.

Study Design and Purpose

• The research aimed to analyze the diagnostic and prognostic value of plasma Alpha-fetoprotein (AFP) among foals affected by different diseases spontaneously. Alpha-fetoprotein concentrations are often proposed as a biomarker for detecting sepsis in foals, particularly those born from mares with artificially induced placentitis.
• The study involved foals less than 72 hours old diagnosed with prematurity (born before day 320 of gestation and displays immature physical attributes), sepsis (confirmed with a positive blood culture and presence of Systemic Inflammatory Response Syndrome – SIRS), or neonatal encephalopathy (damage resulting from hypoxic-ischemic injury).

A Study of Alpha-fetoprotein (AFP)

• The study included 46 foals with an average age of 16 hours, and they were divided into groups based on their diagnosed conditions: prematurity, sepsis, and neonatal encephalopathy.
• AFP levels were measured in plasma collected at the time of their admission to the hospital using a commercially available immunoassay that had previously been validated for horses.
• The study found that AFP concentrations were elevated in the foals in all three research groups—prematurity, sepsis, and neonatal encephalopathy—compared with the healthy foals (P<0.001).

Findings and Implications

• Despite the increased levels of AFP in sick foals, it could not distinguish between different diseases or predict outcomes, making it a non-specific health indicator.
• The overall findings of the research showed a negative correlation between AFP levels and the age of the foal, its weight, monocytes count, and serum amyloid A (SAA) concentration.
• In conclusion, despite AFP being upregulated not only in foals with SIRS and bacteremia but also during prematurity and hypoxic-ischemic injury, it only serves as a general indicator of neonatal health, not being able to differentiate between various diseases and outcomes.