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trisomy 21Down syndrome, mongolism Pediatrics A chromosomal dysgenesis caused by partial or complete duplication of all or part of chromosome 21 appears 3 times; in some only some cells contain the chromosomal defect–ie, mosaicism Clinical MR, microcephaly, short stature, a characteristic facial dysmorphia–flat hypoplastic facies, short/flat nose, upward slanting eyes–Mongolian slant; inner corner of the eyes often has a rounded fold of skin–epicanthal fold; small, low-set ears, thickened, protruding and fissured tongue, joint laxity, pelvic dysplasia, broad hands and feet with shortened digits, a single transverse palmar or simian crease, lenticular opacification, cardiac defects–eg, PDA, endocardial cushion defects, Fallot's tetralogy, esophageal atresia, duodenal atresia, muscle spasms, ↑ risk of ALL, retardation of growth and development is typical; most never reach average adult height Risk of DS ↑ with maternal age–0.7/1000 births ≤ age 30; 34.6/1000 ≥ age 45 Prognosis Compatible with long-term survival Incidence 1:900. See Maternal age.
trisomy 21chromosomal abnormality (three rather than two chromosome 21) causing development of type of Down's syndrome
Patient discussion about trisomy 21
Q. Can Down syndrome occur again? A few years ago, at the age of 32 my sister gave birth to a child that was diagnosed with Down syndrome. Now, at the age of 37 she's pregnant again. Can she have another baby with Down? Does the fact she has a baby with Down means she has higher risk for a second baby with Down?
- Previuosly child with Down Syndrome
Q. assessment of down syndrom
Q. what does enlarged heart mean? is it linked to down syndrome? My wife is 16 weeks pregnant. we did a prenatal US and we were told that the baby hes an enlarged heart and that we are advised to do amniocentesis. A friend of mine had a baby with down syndrome, and he was toled that if they have done this procedure, the doctors could have find it on time and abort the pregnancy. Is there a clear connection between the enlarged hart and the fact that the doctor advised us to do this procedure to down syndrome?
The protocol that most obstetrics use is that if there is anything abnormal in the US there is an automatic referral to an amniocentesis procedure.
the US has a lot of false alarms, so they must check with the more accurate procedure.