A 30 year old presented with a skin lesion in his right axilla. A presumptive diagnosis of staphylococcal skin carbuncle is made & patient is treated with empiric trimethoprim/ sulfamethoxazole. After 2 days, the patient came to emergency with excessive weakness, abdominal pain & dark coloured urine. O/E- vitals are normal & jaundice is present. Lab studies show a drop in Hb from 14 g/dl to 8 g/dl & rise in bilirubin levels. Urine dipstick is positive for bilirubin. Peripheral blood smear is shown below. What could be the possible diagnosis of the patient?