Management of Elevated Alpha-Fetoprotein in Infants

Introduction to Alpha-Fetoprotein

The American Academy of Pediatrics recommends that elevated alpha-fetoprotein (AFP) in infants under 1 month is a physiological finding, as AFP is the main circulating protein in fetal blood and declines rapidly after birth 1, 2

The American College of Medical Genetics and Genomics suggests that serial measurements of AFP every 2-4 weeks are mandatory to distinguish between physiological descending values and pathological persistent or ascending elevations 1, 2
If AFP values do not consistently decrease or increase, immediate investigation is required 1, 2

The American Association for Clinical Chemistry recommends complete liver function tests, including transaminases (AST, ALT), direct and indirect bilirubin, alkaline phosphatase, and GGT 1, 2
Synthetic liver function tests, such as prothrombin time (PT) and partial thromboplastin time (PTT), and albumin levels should also be measured 1, 2
Succinylacetone in blood and urine is a specific diagnostic test for tyrosinemia type 1 1, 2

The American College of Radiology recommends a complete abdominal ultrasound to evaluate hepatomegaly, liver masses, and abdominal anatomy 3, 4, 5
If the ultrasound shows abnormal findings or AFP continues to rise, proceed to magnetic resonance imaging (MRI) with hepatobiliary contrast 3, 4

If succinylacetone is elevated (tyrosinemia type 1), start NTBC therapy immediately and restrict dietary phenylalanine and tyrosine 1, 2
Monitor AFP continuously: it should decrease continuously during the first year of treatment 1, 2
If AFP does not decrease consistently or increases, perform imaging immediately to rule out hepatocellular carcinoma 1, 2

The American Academy of Pediatrics warns that assuming normal AFP excludes malignancy is incorrect 1, 2
Continuous surveillance with periodic imaging is crucial even with normal AFP 1, 2

Urgent referral to a pediatric liver transplant center is indicated for any neonate with acute liver failure 6
Coagulopathy (elevated PT/INR, PTT), hypoalbuminemia, hard hepatomegaly, and elevated bilirubin are factors that require urgent action 1, 2, 6

In infants with overgrowth syndromes, such as Beckwith-Wiedemann, alpha-fetoprotein (AFP) levels tend to be elevated above normal pediatric values during the first years of life, according to the American College of Medical Genetics and Genomics 7
The observed AFP values in hepatoblastoma are typically 10 times higher than those observed in normal neonates under 1 month, as reported by the American College of Medical Genetics and Genomics 8
The expectation is that AFP values will decrease continuously during the first year of treatment, as stated by the American College of Medical Genetics and Genomics 8

During post-treatment surveillance, measurement every 3 months until the fourth birthday is recommended for predisposing syndromes, according to the National Comprehensive Cancer Network 7

It is fundamental to recognize that normal AFP values do not guarantee the absence of hepatocarcinoma or recurrence, requiring continuous surveillance with periodic imaging even with normal AFP, as emphasized by the American College of Medical Genetics and Genomics 8