Answer is D (Coarctation of Aoa) Isolated upper extremity hypeension (200 / 140 mm Hg), together with absent/ diminished femoral pulses is a characteristic feature of coarctation of aoa. Although coarctation of aoa does not commonly present with seizures, these may be seen as a consequence of severe hypeension (BP = 200/140) or complications like intracranial haemorrhage (from Berry aneurysms which are more common in patients with coarctation. Coarctation of Aoa is the most likely diagnosis: Approach (Nelson/Hurst) The classic sign of coarctation of aoa is a disparity in pulsations and blood pressure in arms and legs. The femoral, popliteal, posterior tibial and dorsalis pedis pulses are weak (or absent in upto 40% of patients) in contrast to bounding pulses in the arms and carotid vessels. The blood pressure is the legs is lower than in the arms and 90% of patients with coarctation have hypeension in an upper extremity greater than 95" perecentile for age Age (yrs) 95th percentile (mm Hg) > 1 yrs 110 60 I -- 5 yrs 115 /75 6-10 yrs 125 /85 11 -- 18 yrs 140 /90 A blood pressure of 200 /140 mm Hg in a 10 year old boy suggests severe hypeension (95" percentile at 10 years -- 125/85) Severe hypeension may be seen as a consequence of persistant hypeension in an individual who has not undergone corrective surgery for coarctation, and this usually appears in the second or third decade of life (Hurst) Children with severe/malignant hypeension may develop headaches, seizures and stroke (haemorrhage from Berry aneurysms which are more common in patients with coarctation). Takayasu Aooaeritis may also present with severe hypeension and absent femoral pulses due to acquired midaoic coarctation but this is an uncommon presentation in Takavasu aooaeritis (and hence not the single best answer of choice) Takayasu aeritis (or non specific aooaeritis) is a chronic vasculitis disease of medium and large sized aeries with a strong predilection for aoic arch and its branches. This may lead to stenosis of the involved vessels and hence a picture of acquired coarctation. It may thus produce a clinical picture similar to that of coarctation with disparity in pulsations and blood pressure in arms & legs with hypeension depending on the site of the acquired stenosis. However, this condition is more common in women and most commonly affects the subclavican aery. Hence it more commonly presents with claudication, along with unequal and reduced pulses / BP in the upper extremity than the lower extremity. Also systemic symptoms are more common is Takayasu than in coarctation. Neveheless Takayasu aeritis may affect the Thoracic or Abdominal aoa and present with absent lower limb pulses and upper extremity hypeension like coarctation of aoa. Takayasu aeritis can be picked as the answer if Coarctation of aoa is not provided amongst the options