| Popis: |
Mosaic trisomy 8 (MT8) which is also known as Warkany syndrome 2, is well described chromosomal disorder defined with the existence of three copies of chromosome 8 in some cells of organism. Complete trisomy 8 is very rare and usually is lethal. It occurs in 0, 8% of spontaneous pregnancy loses. Incidence rate varies between 1 in 25, 000 and 1 in 50, 000 births and is more common in males. It displays certain phenotype varieties from normal individuals up to severe malformations. They can or cannot be seen by prenatal diagnostic (US or MRI). The MT8 is characterised by intracranial (agenesis of the corpus callosum, hydrocephalus), face, neck and skull anomalies (everted lips, large dysplastic ears, prominent fore head, broad nose, microphtalmia, cataract), gastroninestinal (diaphragmatic hernia, esophageal atresia, absence of gallbladder), genitourinary (hydronephrosis, reflux), skeletal system anomalies (vertebral anomalies, joint contractions, abnormal metacarpals and metatarsals), congenital cardiovascular disorders(VSD, ASD, great vessel anomalies), deep palmar and plantar lines, neoplastic and hematological disorders. Deep plantar creases are highly characteristic of trisomy 8 mosaicism. Prenatal diagnostic of these very rare syndromes is uncommon. When ultrasound findings are consistent with trisomy 8, prenatal karyotyping should be undertaken. |
