Introduction
Lupus or systemic lupus erythematosus (SLE) is an autoimmune disorder that can cause swelling and inflammation throughout the body. In adults, lupus can occur due to several reasons, such as hormonal changes, environmental factors, and genetic changes. There are many types of lupus, including cutaneous lupus erythematosus (this lupus affects the skin), drug-induced lupus (this type of lupus is caused due to certain medications), and neonatal lupus. Neonatal lupus is not the same as the other types of lupus and was first described by McCuistion and Schoch in 1954.
What Is Neonatal Lupus?
Neonatal lupus refers to an acquired autoimmune disorder that is present at birth. It is not similar to infant lupus (SLE). The affected neonate's mother does not acquire SLE, and so does the affected neonate. It may have clinical manifestations like abnormal systemic, cardiac, and cutaneous growth in newborns. Some defective antibodies are transferred to the newborn from the mother. Neonatal lupus is also known as neonatal lupus syndrome and neonatal erythematous.
What Causes Neonatal Lupus?
When specific antibodies are passed on from the mother to the newborn, this disorder occurs. Antibodies are produced by the immune system to fight off any foreign invading germs or bacteria. In pregnancy, antibodies travel across the placenta from mother to fetus, and the fetus generally does not make the antibodies. However, in the case of neonatal lupus, autoantibodies cross over the placenta.
Two of the major antibodies that contribute to neonatal lupus include:
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Anti-Ro (SSA) Antibody - Anti-Sjogren-syndrome-related antigen A autoantibodies are a type of antinuclear antibody that can lead to many autoimmune disorders like Sjogren disease, systemic lupus erythematosus, and neonatal lupus. These antibodies target the Ro proteins (Ro52 and Ro60). The activity of Anti-Ro (SSA) occurs at the cell surface where Ro proteins are present at the cell membrane. The Anti-Ro (SSA) then binds to the Ro protein. These antibodies in pregnant women can lead to severe complications, and the symptoms usually resolve within six months as the mother's antibodies leave the baby's system.
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Anti-La (SSB) Antibody - These antibodies are mostly seen in the cases of Sjogren's syndrome. Both Anti-Ro (SSB) and Anti-La (SSB) are present in rare cases of neonatal lupus. If both these antibodies are present, it may increase the risk of a newborn having neonatal lupus.
What Are the Clinical Features of Neonatal Lupus?
Some of the common clinical features include:
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Skin changes such as rashes are seen within three months of birth.
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Photosensitivity (unusual reactivity of the skin to sunlight).
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Telangiectasia (dilated capillaries or veins).
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Petechiae (pinpoint type of purpura that shows red or brown non-blanchable spots).
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Congenital heart block may lead to certain symptoms, such as difficulty feeding, fatigue, and tiredness.
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Low platelet count.
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Low white blood cells (neutropenia).
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In some cases, abnormally large liver (hepatomegaly).
What Are the Different Modalities Through Which Neonatal Lupus Can Be Diagnosed?
Skin rashes are clinically evaluated by a doctor. Depending upon the manifestation, an echocardiogram is advised if the heartbeat is found slow during the pregnancy. A blood test is advised to check for the anti-RO and LA antibodies.
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Electrocardiogram (ECG) - It is recommended when a heart block has not already been diagnosed before birth on an ultrasound. ECG uses electric signals in the heart and is a safe and simple procedure. During the test, around 12 electrodes or sensors that are connected to a monitor are attached to the chest and the limbs. The electric signals are recorded, and the computer displays the recording in waves on paper.
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Blood Test - A blood test is done to check for the presence of certain antibodies. First, the blood is taken from the arm’s vein. Next, a healthcare expert will insert a fine needle in the vein, and the blood is drawn out. The procedure may feel a little painful but takes only a few minutes to complete. The blood sample is transferred in a vial or a test tube and sent to the laboratory for further testing.
What Are the Differential Diagnosis of Neonatal Lupus?
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Tinea Corporis - It is a superficial fungal infection of the skin that has very similar symptoms of rashes or lesions as seen in neonatal lupus.
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Congenital Syphilis - It is a sexually transmitted disease (STD) that shows some similar symptoms like red papules or lesions around the face.
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Seborrhoeic Dermatitis - It is a chronic skin condition that affects the face and scalp. It has very similar appearing patches on the face as neonatal lupus lesions.
What Are the Different Methods Through Which Neonatal Lupus Can Be Managed?
Some of the options for treating neonatal lupus include
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To reduce the risk of cardiac neonatal lupus, in pregnant women with Ro and La antibodies, Hydroxychloroquine is given.
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A permanent pacemaker is given if a heart block is detected at birth. A pacemaker is a device that is used to control irregular heartbeat.
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In case of skin rashes, topical sun protection and full sleeves clothes are advised.
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Intravenous (IV) immunoglobulins are effective in treating cardiomyopathy associated with neonatal lupus.
What Are the Complications of Neonatal Lupus?
The most serious neonatal lupus consequence is congenital heart block. The transmission of the heartbeat from the top to the middle of the heart is hampered by it. The conduction system in the center of the heart regulates heartbeat frequency.
Congenital heart block can be of the first, second, or third degree.
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First-Degree Block: The top and bottom chambers of the heart lag slightly in first-degree heart block. However, clinical concerns are typically unaffected by this.
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Second-Degree Block: This type of heart block decreases the heart rhythm by preventing all of the beats from moving from the upper to lower chambers.
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Third-Degree Block: The most serious type of heart block occurs when there is no transmission of beats from the upper to the lower chambers. Symptoms such as blackouts, shortness of breath, or abnormal heartbeats may result from this. Additionally, a person's heart walls may thicken and they may develop a heart muscle disease. In severe circumstances, heart failure or abrupt cardiac arrest might also happen.
Conclusion
Neonatal lupus is a rare autoimmune disorder that is present at birth and is transmitted by the mother. In most cases, the mother is not affected by lupus, but due to certain antibodies like Anti-Ro (SSA), the child is born with this condition. Though this condition can cause some complications, if diagnosed and treated on time can help the child live a long healthy life.
