Page 51 - Textbook of Pathology, 6th Edition

acute and subacute cell injury from various etiologic agents INTRACELLULAR HYALINE. Intracellular hyaline is 35
such as bacterial toxins, chemicals, poisons, burns, high fever, mainly seen in epithelial cells. A few examples are as follows:
intravenous administration of hypertonic glucose or saline 1. Hyaline droplets in the proximal tubular epithelial cells in
etc. cases of excessive reabsorption of plasma proteins.
PATHOGENESIS. Cloudy swelling results from impaired 2. Hyaline degeneration of rectus abdominalis muscle called
regulation of sodium and potassium at the level of cell Zenker’s degeneration, occurring in typhoid fever. The CHAPTER 3
membrane. This results in intracellular accumulation of muscle loses its fibrillar staining and becomes glassy and
sodium and escape of potassium. This, in turn, leads to rapid hyaline.
flow of water into the cell to maintain iso-osmotic conditions 3. Mallory’s hyaline represents aggregates of intermediate
and hence cellular swelling occurs. In addition, influx of filaments in the hepatocytes in alcoholic liver cell injury.
calcium too occurs. Hydropic swelling is an entirely 4. Nuclear or cytoplasmic hyaline inclusions seen in some
reversible change upon removal of the injurious agent. viral infections.
5. Russell’s bodies representing excessive immunoglobulins
MORPHOLOGIC FEATURES. Grossly, the affected in the rough endoplasmic reticulum of the plasma cells
organ such as kidney, liver, pancreas, or heart muscle is (Fig. 3.12).
enlarged due to swelling. The cut surface bulges outwards
and is slightly opaque. EXTRACELLULAR HYALINE. Extracellular hyaline is seen
Microscopically, it is characterised by the following in connective tissues. A few examples of extracellular hyaline
features (Fig. 3.11): change are as under: Cell Injury and Cellular Adaptations
i) The cells are swollen and the microvasculature 1. Hyaline degeneration in leiomyomas of the uterus
compressed. (Fig. 3.13).
ii) Small clear vacuoles are seen in the cells and hence 2. Hyalinised old scar of fibrocollagenous tissues.
the term vacuolar degeneration. These vacuoles represent 3. Hyaline arteriolosclerosis in renal vessels in hypertension
distended cisternae of the endoplasmic reticulum. and diabetes mellitus.
iii) Small cytoplasmic blebs may be seen. 4. Hyalinised glomeruli in chronic glomerulonephritis.
iv) The nucleus may appear pale. 5. Corpora amylacea are rounded masses of concentric hya-
line laminae seen in the prostate in the elderly, in the brain
Hyaline Change and in the spinal cord in old age, and in old infarcts of the
lung.
The word ‘hyaline’ means glassy (hyalos = glass). Hyaline is
a descriptive histologic term for glassy, homogeneous, Mucoid Change
eosinophilic appearance of material in haematoxylin and Mucus secreted by mucous glands is a combination of
eosin-stained sections and does not refer to any specific proteins complexed with mucopolysaccharides. Mucin, a
substance. Though fibrin and amyloid have hyaline appear- glycoprotein, is its chief constituent. Mucin is normally
ance, they have distinctive features and staining reactions produced by epithelial cells of mucous membranes and
and can be distinguished from non-specific hyaline material. mucous glands, as well as by some connective tissues like
Hyaline change is associated with heterogeneous pathologic in the umbilical cord. By convention, connective tissue
conditions. It may be intracellular or extracellular. mucin is termed myxoid (mucus like). Both types of mucin

Figure 3.11 Hydropic change kidney. The tubular epithelial cells are distended with cytoplasmic vacuoles while the interstitial vasculature is
compressed. The nuclei of affected tubules are pale.