What Is Twin Anemia Polycythemia Sequence (TAPS)?
Twin anemia polycythemia sequence (TAPS) is a condition wherein blood distribution is inconsistent between twins that share a placenta (monochorionic), bringing about one baby getting more red blood cells (RBCs) than the other. It is similar to the twin-to-twin transfusion (TTTS). The difference is that the placental links that are formed between the twins in TAPS are smaller than in TTTS.
What Causes TAPS?
TAPS is the after-effect of a lopsidedness of remote connections in the outer layer of the placenta that permit red blood cells to be moved from one baby to the other. The embryo sending blood to its co-twin winds up with a lesser number of red blood cells (iron deficient), while the one getting the blood has too many red blood cells (polycythemia). The condition can occur as a result of monochorionic pregnancy or after fetoscopic laser surgery. This procedure is used to treat TTTS. TAPS can occur as a reaction to this form of laser surgery.
What Are the Risks of Twin Anemia Polycythemia Sequence?
The following may be the risks of twin anemia polycythemia sequence:
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Any history of laser surgery before pregnancy.
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In case of pregnancy that is monochorionic, ie; multiple pregnancies such as twins and triplets.
What Are the Symptoms of TAPS?
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In TAPS, due to the lack of balance in the blood flow between the twins, the beneficiary twin gets excessive red blood cells and is at greater risk of sluggish blood flow, otherwise called polycythemia. This can lead to the formation of blood clumps, known as thrombosis. The other twin has a deficiency of red blood cells and is at a greater risk of developing hydrops and anemia.
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Unlike TTTS, the mothers carrying twins with TAPS do not encounter any symptoms at all. This condition is known to develop gradually over one’s pregnancy. Unlike TTTS, in TAPS, there is no alteration to the amniotic fluid levels.
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Now and again, the twin's placenta, which receives more blood, might seem thickened.
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The liver may develop bright white spots, also known as starry sky liver.
How Are TAPS Evaluated and Diagnosed?
The most pivotal move toward assessing a twin pregnancy for twin anemia polycythemia sequence is to decide if the twins share a solitary placenta. An ultrasound assessment from the get-go in pregnancy (during the primary trimester) can best make this qualification. Twin anemia polycythemia sequence can likewise affect the cardiovascular arrangement of one or the other twin. It is essential to perform a cardiovascular evaluation of the twins during pregnancy to rule out any other complications. The various diagnostic evaluations include-
The evaluation will involve the following exams:
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Ultrasound - An assessment to understand the underlying irregularities in the twins. This test helps to understand the blood distribution between the twins. It is also used to understand the placement and distribution of the placenta.
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Doppler Study of the Fetal Cerebral Arteries - A subset of ultrasound used to gauge the progression of blood through a vein in the fetal cerebrum. This ultrasound can show the blood distribution of the twins.
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The Thickness of Blood - The thickness of blood depends on the blood the twin receives. The more blood, the slower the blood flow, and vice-versa.
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Fetal Echocardiogram - An engaged ultrasound of each twin's heart to look for any heart conditions. TAPS might cause serious cardiovascular strain in the affected twin. This could lead to various heart conditions, such as cardiomegaly (enlarged heart) and various dysfunction of the heart. All twins assessed for TAPS ought to go through a fetal echocardiogram.
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Amniocentesis - A method wherein a small quantity of amniotic liquid is obtained from the sacs encompassing the twins and evaluated for abnormalities. This test is used as a conjunct to other diagnostic and imaging tests to arrive at a diagnosis. Since TAPS grows gradually and can advance undetected, week after week, MCA Doppler studies are suggested in monochorionic pregnancies, starting somewhere in the range of 16 and 18 weeks.
How Is This Condition Treated?
Treatment for twin anemia polycythemia sequence may include the following:
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Early Management - In circumstances where the medical procedure isn't yet demonstrated, close observing with periodic Doppler ultrasound assessments is utilized to assess the state of the two twins and search for indications of movement. At times, a subsequent fetal echocardiogram is utilized too to search for indications of cardiovascular changes; these may, in some cases, be seen before different changes.
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Fetal Selective Laser Ablation - An minimal medical procedure performed on the placenta to disengage the imparting veins. This strategy, additionally called specific laser photocoagulation (SLPC), prevents the sharing of blood from the benefactor to the beneficiary, fully intent on stopping the abnormal blood transfusion.
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Intrauterine Blood Transfusion - In certain cases, laser medical procedure is, as of now, not conceivable because of late gestational age and intrauterine bonding for the weak baby. In these cases, diluting or thinning of the blood to the polycythemic baby can be considered.
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Preterm Delivery - When TAPS happens towards the end of gestation, the most ideal choice of treatment is to opt for an early delivery to prevent any further complications.
What Are the Follow-up Care For TAPS?
The doctor provides a point-by-point postoperative consideration and guidelines if one undergoes fetal mediation. The doctor plans for an ultrasound at appropriate intervals to look for the wellness of the mother and the children. After that test, the doctor prescribes or refers the patient to a maternal-fetal medication expert for somewhere around three weeks of week-after-week ultrasound assessments. The entire process will be taken care of by a multidisciplinary approach.
Conclusion:
TAPS is a condition in which the twins are affected by unequal blood flow. One of the twins gets more blood than the other. The blood flow may be thicker in one twin when compared to the other. This can affect the development of both twins. The symptoms are not felt until late gestation. However, this condition can be diagnosed in a routine ultrasound and managed appropriately. The treatment depends on the stage of the condition and the pregnancy.
