A 20 years old female presented to emergency with high grade swinging fever, abdominal tenderness and flank mass. On CT there was collection around kidney. Antibiotics were staed but patient condition didn't improve after 48 hours. What is the next best treatment option?

Diagnosis based on question- Perinephric Abscess. - Collection of fluid inside kidney- Pyonephrosis- Collection of fluid around kidney- Perinephric Abscess. Perinephric Abscess.- TOC for abscesses- Incision and drainage + Antibiotics.- If no improvement with antibiotics as given in the question/ Deep seated intraabdominal abscess- Percutaneous drainage under USG/CT guidance is preferred over Open surgical drainage.- Nephrectomy is not done because kidney function is not impaired in this case- Observation and follow up is not done because patient condition did not improvened