<prompt> All are true about Down syndrome except:Duodenal atresiaTrisomy 21Simian creaseHypoplasia of middle phalanx of 1st finger  <response>: Ans: D Hypo... Ref: Nelson 18th508; OPG 7th613; 6th 592; Robbins 7th 176-77; Radiology Review Mnuai by Wolfgang Danhert 5th925Systemic ab norma lilies in Down syndrome GIT : Duodenal, ileal andjejunal atresia. tracheoesophogeal fistula, hirsprungs disease, meckels diverticulum, imperforate anus, omphalocle. Eye : Brushfield ed risk of cataract, nystagmus and squint. CVS : Endocardial cushion defect MC, VSD, Ostium primum ASD AV valve malformation. Hearing defects : Serous otitis media;conductive or sensorineural hearing loss Nelson 18th508.Thyroid-dysfunction: Hypothyroidism. Atlanto- occipital dislocationsubluxation. Malignancy : ed risk of AML and ALL Early onset Alzheimer disease Abnormal immune responseTABLE Nelson 18th508 Chromosomal Trisomies and Their Clinical FindingsSyndromeIncidenceClinical ManifestationsTrisomy 21 Down syndrome1600-800 birthsHypotonia, flat face, upward and sian ted palpebral fissures and epicanthic folds, speckled irises Brush field sports;varying degrees of mental and growth retardation ; dysplasia of the pelvis, cardiac malformations, and simian crease; short, broad hands, hypoplasia of middle phalanx of 5th finger, duodenal atresia, and high arched palateTable Nelson 18th508: Additional Disorders in Children with Down SyndromeDuodenal atresiaAnnular pancreasTracheoesophageal fistulaHirschsprung diseaseShort statureShort sternumBrachycephalyDelayed fontanel closureThree fontanelsFrontal sinus hypoplasiaPeripheral joint laxityAtlantoaxial instability C1-C2 subluxationExaggerated space between 1st and 2nd toesMottled skin in infancyDry coarse skin in adolescenceIncreased Risk for Development of Leukemia: AML, ALL 