THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -Acute pyelonephritis is a bacterial infection causing inflammation of the kidneys and is one of the most common diseases of the kidney. Pyelonephritis occurs as a complication of an ascending urinary tract infection (UTI) which spreads from the bladder to the kidneys and their collecting systems.

Detailed explanation-2: -General Pathogenesis Pyelonephritis results mostly from an ascending infection, from the urethra (when colonised by organisms) to bladder and then through the ureters to the renal parenchyma or from a hematogenous spread.

Detailed explanation-3: -The infection ascends the urethra to the bladder, and sometimes to the kidneys, or both. The other possible route is through the bloodstream, usually to the kidneys. Urinary tract infections (UTIs) are almost always caused by bacteria, although some viruses, fungi, and parasites can infect the urinary tract as well.