Renal abscess is usually caused by bacteria from an infection traveling to the kidneys through the bloodstream or by a urinary tract infection traveling to the kidney and then spreading to the kidney tissue.
The treatment options for a renal abscess are intravenous antibiotics and drainage of the abscess by an open operation or by inserting a catheter through a needle in the skin overlying the kidney with X-ray guidance. Nowadays percutaneous drainage is used .
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.