Kidney infections are serious. If left untreated or treated poorly, they can cause life-threatening health complications. Read on as our team at AFC Urgent Care Chapman Highway provides more important information about kidney infections. What Causes Kidney Infections? The most common cause of kidney infections is when bacteria enter the urinary tract through the tube that carries urine from your body (urethra) and multiplies and travels to the kidneys. Bacteria from an infection elsewhere in ...