Diagnostic Approach for Diamond-Blackfan Anemia in Pregnancy

Initial Assessment and Risk Evaluation

• A detailed family history is recommended to identify known inherited disorders and assess for consanguinity, which increases the likelihood of recessive disorders, according to the American College of Obstetricians and Gynecologists 1, 2

Ultrasound-Based Surveillance

• Detailed fetal ultrasound is used to assess for signs of fetal anemia or hydrops fetalis, associated congenital anomalies, and fetal growth parameters, as recommended by the American Institute of Ultrasound in Medicine 1, 2
• Middle cerebral artery (MCA) Doppler studies are used to screen for fetal anemia, with a peak systolic velocity (PSV) >1.5 MoM indicating severe anemia, according to the American College of Obstetricians and Gynecologists 3
• Serial MCA Doppler studies should be performed to monitor for developing anemia, as recommended by the Society for Maternal-Fetal Medicine 1, 3

Invasive Diagnostic Testing

• Amniocentesis or chorionic villus sampling (CVS) is recommended for karyotype analysis, chromosomal microarray analysis, and specific DNA testing for DBA-associated mutations, according to the American College of Medical Genetics and Genomics 2, 4, 5
• Fetal blood sampling (cordocentesis) may be indicated for direct measurement of fetal hemoglobin and hematocrit levels, as recommended by the International Society for Prenatal Diagnosis 4

Genetic Testing Approach

• Fetal DNA obtained by amniocentesis may be required to determine fetal status if the father is heterozygous for the implicated gene, according to the European Journal of Human Genetics 6

Management Considerations

• Serial monitoring with MCA Doppler and ultrasound is recommended throughout pregnancy to detect developing anemia or hydrops, as recommended by the Society for Maternal-Fetal Medicine 1, 3

Common Pitfalls and Caveats

• Other causes of fetal anemia, such as immune causes (red blood cell alloimmunization), infectious causes (parvovirus B19, CMV, toxoplasmosis), and other inherited anemias (alpha thalassemia, G6PD deficiency), should be excluded first, according to the American Academy of Pediatrics 1, 2, 3
• False positive results can occur with MCA Doppler, necessitating confirmation with invasive testing, as recommended by the National Institute of Child Health and Human Development 3