We are often asked what is wrong with Noah. When we say he has Trisomy 8, they then ask, "What is that?" Have you ever wondered the same thing? And was afraid to ask? Well today is March 8th, Trisomy 8 awareness day.
Noah was diagnosed with Trisomy 8 when he was 15 months old. After over a year of wondering and many test we got the diagnosis. It was very devastating to hear but, we finally had answers. We look at all the things that could be be wrong with him and then felt very blessed that he had very few if any of the characteristics. So sadly Noah was hit with the double whammy. He also has Cerebral Palsy due to lack of oxygen at birth and no oxygen given to him to help him out.
For more info on Trisomy 8 read below.......
While you are reading, this do me a favor and keep Noah in your prayers. He is having a MRI and CAT scan today. It is our next step to determine if Noah is a good candidate for a cochlear implant.
Trisomy 8 is defined as the presence of three full copies of chromosome 8 in all of a person's cells. Mosaic trisomy 8 describes the situation that occurs when only a portion of these cells contains three copies of chromosome 8, while others contain the usual two copies of that chromosome. For example, people with mosaic trisomy 8 may have cells in their blood and other tissues with the normal chromosome number, but may have cells in their skin with trisomy 8.
The condition is sometimes also referred to as trisomy 8
mosaicism syndrome (T8mS) and mosaic Warkany syndrome. Common characteristics of T8mS are distinct facial features, including low-set or abnormally shaped ears and a bulbous-tipped nose, eye abnormalities like
strabismus and corneal clouding, bone and tissue abnormalities, various structural heart problems, palate abnormalities,
hydronephrosis,
cryptorchidism, mild to moderate mental delays, and deep hand and feet creases. These characteristics tend to vary widely from person to person.
Characteristics of T8mS vary. In other chromosome
mosaicism conditions, more severe symptoms and a worse prognosis are associated with a larger proportion of cells with an
abnormal chromosome number being present. Interestingly, that does not seem to be the case in T8mS. The percentage of cells with trisomy 8 does not appear to correlate with the types of symptoms the affected person experiences.
The creases on the palms and soles of people with T8mS are the most unique characteristic of the condition. On the palms there may be more arches than usual on the fingertips and a single crease running across the palm. The creases are often deep and vertical, with a furrowed appearance, on the soles of the feet.
People with T8mS often have distinct facial characteristics. This can include a wide upturned nose, thicker and down turned lower lip, and low-set and prominent ears that may not be shaped in the usual way. They may also have abnormalities of the palate, including a cleft (opening) or highly arched palate.
Mental retardation can occur with the condition, and the degree of mental delays varies from mild to moderate.
Other findings in T8mS can include those of the bone and tissues. These may be narrow shoulders, absent knee caps, abnormally shaped toes, tighter joints, slender palms, extra or missing ribs, and
curving of the spine.
Eye abnormalities are seen in T8mS, and the two most common findings are corneal clouding and
strabismus where an eye turns in. These may or may not cause significant vision problems and require treatment. More rare eye problems can include a smaller eye size, smaller eye openings, droopy eyelids, wide-set eyes, tilted optic discs, nearsightedness, retinal abnormalities, and epicanthic folds.
Occasional other characteristics can include structural heart problems,
hydronephrosis, underdeveloped genitalia,
cancer, and testes that have not descended into the scrotal sacs.
Diagnosis
Suspicions about T8mS are usually based on a child being born with unique characteristics, since there usually is no reason one would suspect it, such as a family history of the condition. Blood chromosome testing is widely available to diagnose chromosome abnormalities. If enough cells are carefully analyzed in the laboratory, T8mS can often be found in a blood sample.
In situations where a child with multiple characteristics has normal blood chromosome results, other tissues like the skin can be studied for its chromosome makeup. A trained physician can do a brief procedure called a skin
biopsy to obtain a small skin sample. During this, the physician takes a pencil eraser-sized piece of skin from a child's arm or back. Sometimes this testing reveals the presence of
trisomy 18 in skin cells, which would confirm a diagnosis of T8mS.
Many characteristics of T8mS will not be seen during a
pregnancy. However, a woman may be offered a routine prenatal chromosome testing for other reasons, such as her age or family history. A
chorionic villus sampling (CVS) or
amniocentesis procedure, done in the first two trimesters of pregnancy, can usually identify trisomy 8. Depending on the number of cells that are carefully studied, T8mS may also be identified.
In about 1–2% of CVS procedures that are performed, chromosomal
mosaicism is found. However, this is confined to the placenta and does not represent the chromosomal status of the fetus. Additionally, a few babies reported in the literature were born with T8mS whose mothers had completely normal amniocentesis chromosome results during their pregnancies. For an unknown reason, amniocentesis may not provide the most accurate results with respect to T8mS. This makes it difficult when
counseling and providing information to couples during pregnancy with respect to T8mS.
Individuals with T8mS can also be formally
assessed by a medical geneticist and genetic counselor to aid in diagnosis, discussion of testing options, and interpretation of test results.
Treatment and management
There is no cure for T8mS. Therefore, treatments are based on a person's signs and symptoms.
A cleft palate can be repaired through stages with surgery, often first occurring in the first year of life. This usually requires a multidisciplinary team consisting of a plastic surgeon, pediatric dentist, pediatric anesthesiologist, nurses, dietician/feeding specialist, and
social worker.
Hydronephrosis, if severe enough, can warrant surgery shortly after
birth. The goal is to open the blocked area of the urinary tract and clear the obstruction into the kidney. Surgery may involve a team approach, including a pediatric urologist, pediatric nephrologist, nurses, and surgery technicians.
Congenital heart defects, if severe enough, can require surgery. Surgery varies depending on the problem and may involve a team, including a pediatric cardiologist, pediatric cardiovascular surgeon, pediatric anesthesiologist,
pediatric cardiovascular radiologist, nurses, and surgery technicians.
Strabismus can often be treated with patching therapy or surgery. This may require a team involving a pediatric ophthalmologist, pediatric anesthesiologist, orthoptist, nurses, and surgery technicians. Severe corneal clouding may lead to vision problems, and can sometimes be treated with surgery,
laser therapy, or corneal transplants.
Undescended testicles or testes can be brought down to the proper location in the scrotal sacs by a brief surgical procedure. This can involve a team, including a pediatric urologist, pediatric anesthesiologists, and nurses.
Some characteristics of T8mS do not necessitate treatment as they cause no medical harm. Examples of these include facial features, hand/foot creases, and some tissue and bone changes.
Mental delays and retardation may be
assessed by a
child development team or early childhood program. Extra assistance is sometimes available through early intervention programs and special education in schools. Social workers are useful to connect families to helpful resources.
Prognosis
People with T8mS have a prognosis that is entirely dependent upon the symptoms they experience. Someone born with a severe congenital heart defect may have a poorer prognosis for survival, growth, and development based on this. The average lifespan for someone with the T8mS is estimated to be near normal in the
literature. Medical treatments and surgeries continue to offer hope.
WEBSITES
Chromosomal Mosaicism. Medical Genetics department at University of British Columbia. December 31, 2003 (March 15, 2005).
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Genetic Alliance. 2005 (March 15, 2005).
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The Human Genome Organization–Chromosome 8. (March 15, 2005.)
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ORGANIZATIONS
Chromosome Deletion Outreach, Inc. P.O. Box 724, Boca Raton, FL 33429-0724. Phone/Fax: (561) 395-4252. Email: info@chromodisorder.org.
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UNIQUE Rare Chromosome Disorder Group. P.O. Box 2189, Caterham, Surrey CR3 5GN, UK. Phone/Fax: (44)(0)1883 330766. Email: info@rarechromo.org.
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Deepti Babu, MS, CGC
