Possible kidney infection after a bladder infection?

Patient: I have recently had a bladder infection and was prescribed nitrofurination which helped however i got a fever felt tired and weak and generally flu like symptoms. since coming off them i have had pain in my back and in my side, near my ribs, i have also been sick. Could i have a kidney infection?

Doctor: Certainly Pyelonephritis or Kidney infection might be a caused as a complication of a Cystitis or bladder infection, esp ecially if not treated or when not complying with the treatment.Symptoms of kidney infection such as lower back pain, fever, chills, and bloody urine might be found. If you noticed some of these symptoms, I would suggest you to consult your physician for an evaluation and a urine culture to rule out that possibility. Sometimes due to antibiotics overuse, bacteria might become resistant to mild antibiotics such as Nitrofurantoin, using a more potent antibiotic might be needed.