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P55.1

Billable

ABO isoimmunization of newborn

HCC Category Mapping

V28HCC 109Hemolytic and Aplastic Anemias
0.291

What This Code Means

A condition where the newborn's red blood cells are destroyed by antibodies from the mother due to ABO blood type incompatibility.

Coding Tips

  • ABO incompatibility is more common than Rh but typically causes milder disease
  • Document maternal and infant blood types and antibody titers when available

Clinical Significance

ABO isoimmunization represents maternal-fetal blood group incompatibility leading to hemolysis and potential severe anemia in newborns, requiring immediate monitoring and treatment. This condition can progress to kernicterus if untreated and may require exchange transfusion, making accurate diagnosis and coding essential for care planning.

Documentation Requirements

  • Documentation of ABO blood group incompatibility between mother and baby
  • Evidence of hemolysis with elevated bilirubin levels
  • Maternal antibody testing (anti-A or anti-B antibodies)
  • Newborn blood type and direct Coombs test results
  • Assessment of anemia severity and hemoglobin levels
  • Monitoring for hyperbilirubinemia and kernicterus risk
  • Treatment interventions including phototherapy or exchange transfusion
  • Serial bilirubin monitoring and response to treatment

Commonly Confused Codes

Code Hierarchy

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