Disorders of The Urinary System

Inflammatory Disorders

Cystitis is the inflammation of the urinary bladder. It is often caused by bacterial infection. Females are more prone to cystitis because their shorter urethra makes it easier for bacteria to reach the urinary bladder.

Glomerulonephritis is the inflammation of a kidney involving the glomeruli. It may be caused by bacteria or bacterial toxins. The inflamed glomeruli become more permeable, allowing formed elements and proteins to leak into the glomerular filtrate and remain in the urine.

Pyelonephritis is the inflammation of the renal pelvis and nephrons. If only the renal pelvis is involved, the condition is called pyelitis. These infections result from bacteria carried by blood from other places in the body or by migration of bacteria from distal portions of the urinary tract.

Urethritis is the inflammation of the urethra. It may be caused by several types of bacteria, but the bacterium Escherichia coli is the most common. Urethritis is more common in females.

Non-Inflammatory Disorders

Diuresis, or polyuria, is the excessive production of urine. It results from inadequate tubular reabsorption of water and is characteristic of diabetes insipidus and diabetes mellitus.

Renal calculi, or kidney stones, result from crystallization of uric acid or of calcium or magnesium salts in the renal pelvis. They can cause extreme pain, especially when moving through a ureter by peristalsis. Ultrasound waves can be used to break up the stones, as an alternative to surgery.

Renal failure is characterized by a reduction in urine production and a failure to maintain the normal volume and composition of body fluids. It may occur suddenly (acute) or gradually (chronic). Renal failure leads to uremia, a toxic condition caused by excessive nitrogenous wastes in the blood, and ultimately to anuria, a cessation of urine production. Hemodialysis and/or a kidney transplant may be necessary.