Triploid syndrome

Triploid syndrome, also called triploidy, is a chromosomal disorder in which a fetus has three copies of each chromosome instead of the normal two. If this occurs in only a few cells, it is called a triploid genetic mosaic and is less severe.

In humans, most fetuses affected by this chromosomal anomaly, one of the most common, do not complete their embryonic development, resulting in spontaneous abortion, and the few that are born die prematurely.

Signs and symptoms

Fetus with triploid syndrome

Triploid syndrome

Many organ systems are affected by triploidy, but the central nervous system and bone are the most severely affected:

The central nervous system suffers from trifloidy diseases that include: holoprosencephaly, hydrocephalus (augmented amount of the fluid inside the brain), ventriculomegaly, chiari malformation, agenesis of the callosum body and neuronal tube defects.

Bone manifestations include leporino lip / palate, hypertelorism, equinovaro foot and fingertips three and four.

congenital heart disease, hydronephrosis, onfalocele and meningocele (spina bifida) are also common. Quistic hygrome, they occur but they are unusual.

The triploid fetus has a restriction of intrauterine growth that begins early in pregnancy, approximately 12 weeks, and does not affect the head as severely as the body. It suffers from Oligodramnios, which means low levels of fluid, this factor is common in pregnancies with triploidy. The placenta has common abnormalities in triploidy. The most frequent, is the extended placenta and can have cysts inside. In some cases, the placenta can be unusually small, having paused in its growth.

During the first quarter, the fetus with triploidy has a thicker fluid under its skin behind its neck, which requires observation during the first and second trimester of gestation.

The mother will usually have high levels of protein, which include the fetoprotein alpha (AFP) and human chorionic gonadotropin (HCG). Symptoms that are included but that are limited to swelling, edema, or hypertension.

Children can show facial abnormalities, micrognathy, leporino lip, spina bifida, as well as other births can result in kidney complications, limbs, and complications of the umbilical cord. They are also tendentious to be smaller than a normal baby size, a problem that arises while the child is still a fetus.

Causes

Triploidy is caused by an extra set of chromosomes.

TRIPLOIDY CAN BE OF THE FERTILIZATION OF TWO SAMPLES TO AN OVULO (POLISPERMIA) occurs in (60%) or a sperm that fertilizes an ovule with two copies of each chromosome and appears in one (40%). These are known as Diandrica Fertilization and Diginic Fertilization. The pregnancies caused by diginic fertilization are more likely to end just before the baby comes to term. The pregnancies caused by Diandrica result in an abortion towards the first quarter.

Another factor known how pregnancy with hydatiform cool can cause triploidy. It is known that it can cause an early termination, cancer, and even a second molar pregnancy.

DIAGNOSIS

TRIPLOIDY can dramatically raise alpha-fetoprotein levels. In obstetric ultrasound, the abnormalities of the bone system, the central nervous system, heart, abdomen, and the kidneys are visible in the most severe cases that begin in 12-14 weeks of pregnancy. The abnormalities of the placenta were associated with a triploid pregnancy becoming visible in 12-14 weeks. Placentomegaly or restriction of intrauterine growth are the typical findings that drive the evaluation of triploidy, although the Oligohydramnios can be the first sign in some cases. Placentomegaly, is not a pathogenomonic of triploidy because, in some cases, the placenta ages.

Triploidy has to be distinguished from Trisomy 13 and Trisomy 18, which may seem similar in ultrasound. Genetic tests allow a definitive diagnosis.

A sample of amniotic fluid can also be examined to diagnose 99.99% triploidy.

forecast

The majority of fetuses with triploidy do not survive the birth, and those who normally die in days. There is no treatment for triploidy, palliative care is given if a creature survives at birth. If triploidy is diagnosed during pregnancy, voluntary interruption is often offered as an option due to additional health risks for the mother (preeclampsia, a potentially deadly condition, or a coriocarcinoma, a type of cancer). If a mother decides to have pregnancy until the term or until spontaneous abortion occurs, doctors will closely control it in case any of the conditions are developed.

Mosaic triploidy has an improved prognosis, but affected people have cognitive disabilities from moderate to serious.

EPIDEMIOLOGY

Triploidy affects approximately 1–2% of pregnancies, but most abort in early development stages. At birth, male gametes with triploidy are 1.5 times more frequent than female gametes.