Hemolytic disease of the newborn
Hemolytic disease of the fetus and newborn (HDFN); Erythroblastosis fetalis; Anemia - HDN; Blood incompatibility - HDN; ABO incompatibility - HDN; Rh incompatibility - HDNHemolytic disease of the newborn (HDN) is a blood disorder in a fetus or newborn infant. In some infants, it can be fatal.
Normally, red blood cells (RBCs) last for about 120 days in the body. In this disorder, RBCs in the blood are destroyed quickly and thus do not last as long.
Causes
During pregnancy, RBCs from the unborn baby can cross into the mother's blood through the placenta. HDN occurs when the immune system of the mother sees a baby's RBCs as foreign. Antibodies then develop against the baby's RBCs. These antibodies attack the RBCs in the baby's blood and cause them to break down too early.
HDN may develop when a mother and her unborn baby have different blood types. The types are based on small substances (antigens) on the surface of the blood cells.
There is more than one way in which the unborn baby's blood type may not match the mother's.
- A, B, AB, and O are the 4 major blood group antigens or types. This is the most common form of a mismatch. In most cases, this is not very severe.
A, B, AB, and O
A, B, AB, and O are the 4 major blood types. The types are based on small substances (molecules) on the surface of the blood cells. When people who ...
Read Article Now Book Mark Article - Rh is short for the "rhesus" antigen or blood type. People are either positive or negative for this antigen. If the mother is Rh-negative and the baby in the womb has Rh-positive cells, her antibodies to the Rh antigen can cross the placenta and cause very severe anemia in the baby. It can be prevented in most cases.
Rh-negative
Blood typing is a method to tell what type of blood you have. Blood typing is done so you can safely donate your blood or receive a blood transfusio...
Read Article Now Book Mark Article - There are other, much less common, types of mismatch between minor blood group antigens. Some of these can also cause severe problems.
Symptoms
HDN can destroy the newborn baby's blood cells very quickly, which can cause symptoms such as:
- Edema (swelling under the surface of the skin)
Edema
Swelling is the enlargement of organs, skin, or other body parts. It is caused by a buildup of fluid in the tissues. The extra fluid can lead to a ...
Read Article Now Book Mark Article - Newborn jaundice which occurs sooner and is more severe than normal
Newborn jaundice
Newborn jaundice occurs when a baby has a high level of bilirubin in the blood. Bilirubin is a yellow substance that the body creates when it replac...
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Exams and Tests
Signs of HDN include:
- Anemia or low blood count
Anemia
Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. Different type...
Read Article Now Book Mark Article - Enlarged liver or spleen
- Hydrops (fluid throughout the body's tissues, including in the spaces containing the lungs, heart, and abdominal organs), which can lead to heart failure or respiratory failure from too much fluid
Hydrops
Hydrops fetalis is a serious condition. It occurs when abnormal amounts of fluid build up in two or more body areas of a fetus or newborn. It is a ...
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Which tests are done depends on the type of blood group incompatibility and the severity of symptoms, but may include:
- Complete blood count and immature red blood cell (reticulocyte) count
Complete blood count
A complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...
Read Article Now Book Mark Article - Bilirubin level
Bilirubin level
The bilirubin blood test measures the level of bilirubin in the blood. Bilirubin is a yellowish pigment found in bile, a fluid made by the liver. Bi...
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Treatment
Infants with HDN may be treated with:
- Feeding often and receiving extra fluids.
- Light therapy (phototherapy) using special blue lights to convert bilirubin into a form which is easier for the baby's body to get rid of.
Light therapy (phototherapy)
Bili lights are a type of light therapy (phototherapy) that is used to treat newborn jaundice. Jaundice is a yellow coloring of the skin and eyes. ...
Read Article Now Book Mark Article - Antibodies (intravenous immunoglobulin, or IVIG) to help protect the baby's red cells from being destroyed.
- Medicines to raise blood pressure if it drops too low.
- In severe cases, an exchange transfusion may need to be performed. This involves removing a large amount of the baby's blood, and thus the extra bilirubin and antibodies. Fresh donor blood is infused.
Exchange transfusion
Exchange transfusion is a potentially life-saving procedure that is done to counteract the effects of serious jaundice or changes in the blood due to...
Read Article Now Book Mark Article - Simple transfusion (without exchange). This may need to be repeated after the baby goes home from the hospital.
Outlook (Prognosis)
The severity of this condition can vary. Some babies have no symptoms. In other cases, problems such as hydrops can cause the baby to die before, or shortly after, birth. Severe HDN may be treated before birth by intrauterine blood transfusions.
Prevention
The most severe form of this disease, which is caused by Rh incompatibility, can be prevented if the mother is tested during pregnancy. If needed, she is given a shot of a medicine called RhoGAM at certain times during and after her pregnancy. If you have had a baby with this disease, talk with your health care provider if you plan to have another baby.
References
Kemper AR, Newman TB, Slaughter JL, et al. Clinical Practice Guideline Revision: Management of hyperbilirubinemia in the newborn infant 35 or more weeks of gestation. Pediatrics. 2022;150(3):e2022058859. PMID: 35927462 pubmed.ncbi.nlm.nih.gov/35927462/.
Rodrigue BB, Sloan SR. Pediatric transfusion medicine. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 119.
Simmons PM, Magann EF. Immune and non-immune hydrops fetalis. In: Martin RJ, Fanaroff AA, Walsh MC, eds. Fanaroff and Martin's Neonatal-Perinatal Medicine: Diseases of the Fetus and Infant. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 23.
Intrauterine transfusion - illustration
Erythroblastosis fetalis is a condition manifested by anemia that develops in an unborn infant when maternal antibodies, usually caused by Rh incompatibility between the mother's blood type and that of the fetus, attack the red blood cells of the fetus. An intrauterine transfusion of blood may be indicated.
Intrauterine transfusion
illustration
Antibodies - illustration
Antigens are large molecules (usually proteins) on the surface of cells, viruses, fungi, bacteria, and some non-living substances such as toxins, chemicals, drugs, and foreign particles. The immune system recognizes antigens and produces antibodies that destroy substances containing antigens.
Antibodies
illustration
Intrauterine transfusion - illustration
Erythroblastosis fetalis is a condition manifested by anemia that develops in an unborn infant when maternal antibodies, usually caused by Rh incompatibility between the mother's blood type and that of the fetus, attack the red blood cells of the fetus. An intrauterine transfusion of blood may be indicated.
Intrauterine transfusion
illustration
Antibodies - illustration
Antigens are large molecules (usually proteins) on the surface of cells, viruses, fungi, bacteria, and some non-living substances such as toxins, chemicals, drugs, and foreign particles. The immune system recognizes antigens and produces antibodies that destroy substances containing antigens.
Antibodies
illustration
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Review Date: 12/31/2023
Reviewed By: Mary J. Terrell, MD, IBCLC, Neonatologist, Cape Fear Valley Medical Center, Fayetteville, NC. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.