What are the causes of cell injury?

Causes of Cell Injury: 

The causes of cell injury range from the external gross physical violence of an automobile accident to subtle internal abnormalities, such as a genetic mutation causing lack of a vital enzyme that impairs normal metabolic function. Most injurious stimuli can be grouped into the following broad categories.

1. Oxygen Deprivation. Causes of hypoxia include reduced blood flow (celled ischemia), inadequate oxygenation of the blood due to cardiorespiratory failure, and decreased oxygen-carrying capacity of the blood, as in anemia or carbon monoxide poisoning (producing a stable carbon monoxyhemoglobin that blocks oxygen carriage) or after severe blood loss.

2. Physical Agents. Physical agents capable of causing cell injury include mechanical trauma, extremes of temperature (burns and deep cold), sudden changes in atmospheric pressure, radiation, and electric shock.

3. Chemical Agents and Drugs. Oxygen at high concentrations is toxic, Arsenic, Cyanide, Mercuric salts.

4. Infectious Agents. Rickettsiae, Bacteria, Fungi, and higher forms of parasites.

5. Immunologic Reactions. Injurious reactions to endogenous self-antigens are responsible for several autoimmune diseases.

6. Genetic Derangements.

7. Nutritional imbalance. Protein-calorie deficienciency, Deficiencies of specific vitamins, Atherosclerosis, Obesity.