A 13 year old male patient presented to Kamineni intitute of medical sciences with complaints of leg pain and shortness of breath since 4 days The child was apparently asymptomatic 1 year back. Then his guardians noticed that he was gaining weight . The child mentioned that he gained around 15 kgs in that one year. (from 35 kgs to 50 kgs). Along with that, he developed shortness of breath . It was grade 1 breathlessness ( mMRC classification ) which did not progress. 6 days back , the child developed moderate, continuous and dragging type of pain in the legs extending down from the knees bilaterally. The child's sleep was disturbed due to pain. It relieved only on medications. There is H/o fever 2 days back which was low grade intermittent fever that subsided on medication. There is no H/o cough, wheeze, chest pain, palpitations, syncopal attacks, dizziness There is no H/o vomiting, headache, anorexia, burning micturition, abdominal pain or decreased urine output. ...