nephr-, nephro-, nephri-, -nephric

A kidney-like organ, being either part of the most anterior pair of three pairs of organs in a vertebrate embryo, disappearing early in the embryonic development of higher vertebrates, but functioning as a kidney in some simple vertebrates, such as the lamprey.

1. Inflammation of the kidney and its pelvis caused by bacterial infection: "Pyelonephritis is determined by a laboratory diagnosis of the urine (urinalysis) which reveals white blood cells (pyuria or pus in the urine) and bacteria in the urine (bacteriuria)."

"Usually, pyelonephritis shows an increase in circulating white cells in the blood (leucocytosis)."

2. Bacterial infection of the kidney that can be acute (sudden) or chronic (slow, subtle, and stubborn): "Pyelonephritis is usually a result of bacteria going up from the bladder and then on into the ureters to infect the kidneys."

"The symptoms of pyelonephritis include flank (side) pain, fever, shaking chills, sometimes foul-smelling urine, urgency (to urinate), frequency (urinating), and general malaise."