Pyelonephritis: Nursing

Pyelonephritis is an ascending urinary tract infection that causes inflammation of the kidneys and the renal pelvis.

Alright, let’s quickly review the anatomy and physiology of the urinary tract. The kidneys are bean-shaped organs located behind the peritoneum on either side of the vertebral column, just below the rib cage. Now, the kidneys are composed of the renal parenchyma and a collecting system. The renal parenchyma is the solid, functional part of the kidneys, where blood is filtered and urine is produced. This urine is then drained into the renal pelvis, which then narrows to form the ureter, and transports urine to the bladder. Ultimately, urine exits the bladder through another structure called the urethra.

Now, pyelonephritis is most often caused by bacterial infection; and the most common bacteria are Escherichia coli. Other potential bacteria include Proteus species, Enterobacter species, Enterococcus species, and Klebsiella species, as well as Pseudomonas aeruginosa. Less frequently, pyelonephritis is caused by Staphylococcus species, Salmonella species, and fungi like Candida species.

One of the main risk factors for pyelonephritis is urinary stasis or retention. This occurs when the bladder is not able to completely empty, and can be associated with prolonged bed rest or paralysis, or with obstruction of the urinary tract. Obstruction can be caused by structural abnormalities like strictures; kidney stones or tumors; and scarring from pelvic radiation or surgery, recurrent infections, or traumatic injuries.