<prompt> A 10-year old boy presents to the pediatric emergency unit with seizures. Blood pressure in the upper extremity measured as 200140 mm Hg. Femoral pulses were not palpable. The most likely diagnosis amongst the following is:Takayasus aooaeritisRenal parenchymal diseaseGrand mal seizuresCoarctation of aoa  <response>: Isolated upper extremity hypeension 200140 mm Hg, with absentdiminished femoral pulses, is characteristic of coarctation of the aoaSeizures may be due to severe hypeension or due to intracranial haemorrhagefrom berry aneurysms which are more common in patients with coarctationThe classic sign of coarctation of the aoa is a disparity in pulsations and blood pressures in arms and legsThe femoral, popliteal, posterior tibial and dorsalis pedis pulses are weak or absent in about 40 of patients in contrast to bounding pulses in the arms and carotid vesselsBP in the legs is lower than in the arms and 90 of patients have hypeension in upper extremity greater than the 95th percentile for ageAge yrs95th percentile mm Hg1 110601-5115756-101258511-1814090Takayasu aooaeritis may also present with severe hypeension and absent femoral pulses due to acquired mid-aoic coarctation but this is an uncommon presentationMost commonly affects subclan aery and more commonly presents with claudicationCoarctation TakayasuMore commonMore common in boysUpper extremity hypeensionBounding pulses in arms and diminished or absent pulses in lower limbsHypeension is frequentLess commonMore common in girls 8:1 f:mAbsent or decreased upper limb pulses and blood pressure difference between left and right arms are characteristicHypeension is frequentSystemic symptoms are more commonref: Harrisons 18e p1925 