Intravenous immunoglobulin (IVIG) is used in the treatment of immune deficiencies and autoimmune or inflammatory diseases, such as hemolytic disease of the fetus and newborn (HDFN).
IVIG is made up of pooled antibodies from over 1000 healthy donors and is used to boost the immune system. In autoimmune diseases, it helps block the destruction of your own cells. In HDFN, it is used off-label to delay the onset of severe fetal anemia. It is an effective treatment, but there is a risk of side effects for the pregnant mother, ranging from mild to severe.
What is HDFN?
Hemolytic disease of the fetus and newborn (HDFN) is an immune-mediated red blood cell disorder that occurs when a baby’s RBCs break down quickly, which is called hemolysis. HDFN is caused by a mismatch between a mother’s and her baby’s blood type (A, B, AB, or O) or Rhesus (Rh) factor (Rh-positive or Rh-negative) during pregnancy.
Potential side effects of IVIG
The most common side effects of IVIG use in HDFN-affected pregnancies are headache and skin rash, followed by fever, chills and fatigue. Most reactions are mild and occur in 5% of cases. Side effects are more likely to occur as a result of the first infusion, or in cases where the IVIG changes. Slow infusion rates help to prevent side effects.
Rare liver-related adverse events
Elevated levels of liver enzymes (both ALT and ATS) or transaminitis have been reported in some cases, but liver enzymes returned to normal levels eight to 10 days after discontinuing the IVIG infusion. The onset of transaminitis is thought to be a result of maltose-containing stabilizing agents in IVIG preparation. Amino acids can also be used as stabilizing agents, which carry less risk.
Rare serious liver complications can be prevented by avoiding maltose-containing stabilizing agents and ensuring close and constant monitoring. In people with renal failure or diabetes, sugar-stabilized IVIG should also be avoided.
Other rare but serious side effects occur in less than 1% of patients being treated with IVIG. They include kidney failure, anaphylaxis, arthritis, inflammation of the brain and hemolytic anemia.
Although liver-related adverse events are rare, they may occur without warning. There are also reports of cardiac, renal and hematological toxicities occurring in patients treated with IVIG. It is therefore advised to perform a physical exam, a review of the medical history and full blood test, renal function test and liver function test prior to IVIG therapy to understand the potential risks of IVIG.
Who should not receive IVIG?
There are no contraindications to receiving IVIG during an HDFN-affected pregnancy. However, each IVIG product is prepared differently, and they may provoke different reactions.
For example, existing conditions such as diabetes mellitus, existing renal disease, hypovolemia or sepsis are risk factors for sucrose-containing products.
To intervene quickly in the case of an adverse event, the patient should receive IVIG under close medical supervision and be carefully monitored throughout the treatment.
