21. Pyelonephritis abscedens. Necrosis of papilla

Organ: Kidney

Description:

Necrosis of the papilla (or pyramids) are visible as greyish foci of triangular-like shape.

Diagnosis: Acute pyelonephritis

Causes:

Ascending bacterial infection from urinary tract

Theory:

Another morphological sign of acute pyelonephritis is the presence of many microabscesses, however this can’t be seen on this preparation.

Acute pyelonephritis commonly occurs as a complication of hydronephrosis after an obstruction of the lower urinary tract, commonly by a kidney stone. Diabetics are especially vulnerable to develop acute pyelonephritis.

Acute pyelonephritis can lead to sepsis.