What in a person's diet/way of life could bring about sudden and severe kidney infections?

?XS alcohol or drugs: Kidney infections develop from bladder infections. Not emptying bladder after sex is a common cause of utis, sub-optimal toilet hygiene-wiping back to front or keeing thighs closed with urinating can trap urine in vagina and behind labia making nice environment for bacteria. Bubble-bath and tub baths rather than showers are all initial causes. You may have bladder reflux, or lack immunoglobulins.