Physiologic Causes

1. Endocrine abnormalities. Addison disease, Cushing disease, hypothyroidism, hypoparathyroidism.

2. Infectious disease. Meningitis, encephalitis, encephalopathies, abscess formation, Reye syndrome (aspirin associated with influenza, varicella).

3. Autoimmune disorders. Systemic lupus erythematosus, antiphospholipid antibody syndrome.

4. Metabolic abnormalities? Hypoxemia, hyperammonemia, kernicterus, lead toxicity, acute osmolar changes (diabetic ketoacidosis, hypernatremia).

5. Medications. Steroid withdrawal, vitamin A (retinoic acid), cyclosporine, levothyroxine, lithium, sulfonamides, tetracy-clines.

C. Edema. Edema of neuronal cells is the common endpoint producing increased ICP in many of the preceding conditions. There are two types of edema to consider:

1. Cytotoxic. Sodium-potassium pump fails, as does calcium transport, causing fluid to enter cells.

2. Vasogenic. Blood-brain barrier is defective, and fluid enters the interstitial space.

0 0

Post a comment