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Short answer What ABO incompatibility looks like Common questions Related questions SourcesABO incompatibility shows up either as a sudden reaction during a blood transfusion, with fever, chills, back or chest pain and dark urine, or as jaundice in a newborn during the first day of life.
Which set of symptoms you see depends on the setting. A transfusion reaction from mismatched blood usually begins within minutes of the transfusion starting, which is why staff stay close and check vital signs early. In a newborn, the picture is quieter: yellowing of the skin and eyes in the first 24 hours, sleepiness, poor feeding, and pale color. Knowing your own blood type and making sure it is on file at your hospital and in your prenatal records helps your care team catch a mismatch before it matters. Newborn jaundice that appears on day one is always checked with a bilirubin test rather than by eye alone.
What ABO incompatibility looks like
Common questions
What are the symptoms of ABO incompatibility?
ABO incompatibility causes symptoms in two settings. During a transfusion of mismatched blood, signs usually start within minutes: fever, chills, chest or lower back pain, nausea, flushing, shortness of breath, dark or red urine, a fast heartbeat, or a drop in blood pressure. Staff stop the transfusion at once and treat the reaction. In a newborn whose blood type differs from the birthing parent's, the main sign is jaundice in the first 24 hours, sometimes with pale skin, sleepiness, poor feeding, and an enlarged liver or spleen. Both situations need prompt medical care, and a newborn with day one jaundice needs a bilirubin level checked.