This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fluid & Electrolyte, Subject name: Pediatrics
[{'content': 'A 14-year-old boy was brought in a collapsed state with history of 2 episodes of vomiting and had feeble pulse and cold, clammy limbs. ECG is given (Figure). What is the diagnosis? \nSelect and explain. \nA. Hypokalemia, B. Hyperkalemia, C. Hypocalcemia, D. Hypomagnesemia', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans: (b) HyperkalemiaRef: Nelson Textbook of Pediatrics, 20th edition, Page 360ECG shows classical 'sine wave pattern' associated with hyperkalemia.Electrolyte abnormalityECG findingsHypokalemia (< 2.5 meq/L)Prolonged PR IntervalReduction in T wave amplitude / flattening / inversion ST depression Appearance of U waveHyperkalemia Mild (5.5 to 6.6 meq/L)Peaked T waves Prolonged PR segmentModerate (6.5 to 8 meq/L)Loss of P wave Prolonged QRS complex ST segment elevation Ectopic beast and escape rhythmSevere (> 8.0 meq/L)Progressive widening of QRS complex Sine wave Ventricular fibrillation AsystoleHypocalcemiaProlonged QTc segment (secondary to lengthening of ST segment)HypomagnesemiaST segment depression Tall, peaked T wavesFlat T waves or depression in the precordiumU wavesLoss of voltagePR prolongationWidened QRS complex", 'role': 'assistant'}]