M01 - Cloudy Swelling - Kidney

This 52 year old man was in hypotensive shock following a road accident in which he received multiple fractures and other internal injuries. He died 24 hours after the accident.

Histology:
The changes are present in the renal tubules particularly the straight segment of the proximal convoluted tubules and are best seen mid-cortex. The cells lining the tubules are ballooned and vacuolated. In most cells the nucleus is intact but a careful search shows some cells where the nuclei are very densely stained (pyknosis) indicating irreversible damage to the cell.

Q. What mechanism underlies the swelling and vacuolation of the cells?

M03 - Fatty Liver

At autopsy the liver was enlarged and the surface was yellow in colour and greasy to touch (the patient was a heavy drinker).

Histology:
The lobular achitecture of the liver is maintained but the majority of the cells contain clear spaces in the cytoplasm. The nucleus is often pushed to one side. the clear spaces contained fat which has been dissolved out during the processing of the tissue.

M04 - Ischemic Necrosis - Liver

An 82 year old woman was admitted with obstructive jaundice of 3 weeks duration eight weeks after a partial gastrectomy for carcinoma of the stomach.
At laparotomy she had a mass in the head of the pancreas which was obstructing the common bile duct. A cholecyst-jejunostomy was performed to relieve the obstruction. The patient developed peritonitis from rupture of the gallbladder and died three weeks later.

At autopsy the protal vein was thrombosed and there were numerous infarcts in the liver. The mass in the pancreas was identical histologically to the carcinoma of the stomach.

Histology:
At the lower power view note that the pale areas are necrotic liver. Looking at higher magnification, you will see that the necrotic areas show no nucei but th ecell outlines are still evident.
At the periphery of the dead tissue there is cellular reaction. Becuae of postmortem autolysis it is difficulet to identify the cells with accuracy but they include polymorphonuclear leukocytes (neutrophils, PMNs) and cells which are probably macrophages.

M04
42946 x 29472 @ 20X

M05 - Metastatic Calcification

This 63 year old woman had extensive metastatic deposits of breast carcinoma in the skeleton with severe destruction of bone, the occurrence of pathological fractures in the ribs and femur and collapse of several vertebrae.
At autopsy metastatic calcification was noted in the lungs, kidneys and stomach.

This is a section of stomach stainde with Von Kossa stain. The calcium deposits are stained in black.

M05
51535 x 12937 @ 20X

M56 - Normal Uterus

Compare this slide of the normal uterus with the next slide which is an example from a pregnant uterus (inwhich we see hypertrophy of uterine smooth muscle cells).

M57 - Hypertrophy of Myometrium

Uterine tissue sample from a 25 year old pregnant woman.

Histology:
The uterine smooth muscle shows marked enlargement of the cells (hypertrophy) involving nucleus and cytoplasm as compared to a non-pregnant uterus (see slide M56 above).
This is an example of physiological hypertrophy. After birth a pregnant uterus rapdily decreases in size and the smooth muscle cells return to their normal size.

Q. What are likely to be the stimuli to hypertrophy?