Encephalopathy is a term that means brain disease, damage, or malfunction. Encephalopathy can present a very broad spectrum of symptoms that range from mild, such as some memory loss or subtle personality changes, to severe, such as dementia, seizures, coma, or death. In general, encephalopathy is manifested by an altered mental state that is sometimes accompanied by physical manifestations (for example, poor coordination of limb movements).
The term encephalopathy, in most cases, is preceded by various terms that describe the reason, cause, or special conditions of the patient that leads to brain malfunction. For example, anoxic encephalopathy means brain damage due to lack of oxygen, and hepatic encephalopathy means brain malfunction due to liver disease. Additionally, some other terms either describe body conditions or syndromes that lead to a specific set of brain malfunctions. Examples of these are metabolic encephalopathy and Wernicke’s encephalopathy (Wernicke’s syndrome). There are over 150 different terms that modify or precede “encephalopathy” in the medical literature; the purpose of this article is to introduce the reader to the main categories of conditions that fall under the broad term of encephalopathy.
What causes encephalopathy?
The causes of encephalopathy are both numerous and varied. Some examples of causes of encephalopathy include:
• infectious (bacteria, viruses, parasites, or prions),
• anoxic (lack of oxygen to the brain, including traumatic causes),
• alcoholic (alcohol toxicity),
• hepatic (for example, liver failure or liver cancer),
• uremic (renal or kidney failure),
• metabolic diseases (hyper- or hypocalcemia, hypo- or hypernatremia, or hypo- or hyperglycemic),
• brain tumors,
• many types of toxic chemicals (mercury, lead, or ammonia),
• alterations in pressure within the brain (often from bleeding, tumors, or abscesses), and
• poor nutrition (inadequate vitamin B1 intake or alcohol withdrawal).
These examples do not cover all of the potential causes of encephalopathy but are listed to demonstrate the wide range of causes.
Although numerous causes of encephalopathy are known, the majority of cases arise from several major categories (some examples in parentheses):
1. infection (HIV, Neisseria meningitides, herpes, and hepatitis B and hepatitis C),
2. liver damage (alcohol and toxins),
3. brain anoxia or brain cell destruction (including trauma), and
4. kidney failure (uremic).
Some drugs may cause encephalopathy; for example, posterior reversible encephalopathy syndrome (PRES) may occur due to the use of drugs like tacrolimus and cyclosporine. This syndrome manifests with symptoms of headache, confusion, and seizures.
Diagnosis
The diagnosis of encephalopathy is usually made with clinical tests done during the physical examination (mental status tests, memory tests, and coordination tests) that document an altered mental state. In most cases, findings on clinical tests either diagnose or presumptively diagnose encephalopathy. Usually, the diagnosis occurs when the altered mental state accompanies another primary diagnosis such as chronic liver disease, kidney failure, anoxia, or many other diagnoses.
Source: https://www.medicinenet.com/encephalopathy/article.htm#encephalopathy_facts
