This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Paediatrics, Subject name: Pediatrics
[{'content': 'All of the following antenatal screening tools indicate increased risk of Down syndrome EXCEPT? \nSelect and explain. \nA. Decreased Nuchal fold thickness, B. Increased Inhibin level, C. Absence of nasal bone, D. Decreased PAPP-A level', 'role': 'user'}, {'content': "Answer: A \nExplanation: Antenatal Screening for Down's Syndrome USG - Nuchal Thickness > 3 mm 11 - 14 weeks of gestation - Absence of nasal bones - Sho femur - Duodenal Atresia Biochemical Tests 1st Trimester - b-HCG, PAPP-A (Pregnancy associated Plasma Protein - A) (Dual Test) 2nd Trimester QTriple Test - AFP (a-Fetoprotein) + b-hCG + Unconjugated Estirol Quadruple Test - Triple Test + Inhibin Mnemonic HI High (||): HCG & Inhibin levels increase in Down syndrome Integrated Test - Best test screening Down's syndrome (Sensitivity - 95-97%) - Maternal age + 1st Trimester (NT + PAPP-A) + Quadruple Test (2nd Trimester) Confirmatory test for antenatal Dx of Down syndrome - Fetal karyotyping, for which genetic material may be obtained by- - Chorionic Villous Sampling (CVS) - Amniocentesis - Cordocentesis (Percutaneous Umbilical cord Blood sampling) But these are invasive procedures that carry risk of aboion.", 'role': 'assistant'}]