Encephalopathy, a neurological disease with multiple causes

What is encephalopathy? What are its risks for patient health? How is the diagnosis made and what are the treatments? TipsForWomens takes stock.

What is encephalopathy?

Encephalopathy corresponds to a global damage to the brain generally linked to an underlying disease. There are several types of encephalopathy, each caused by different factors.

What are the causes of encephalopathy?

An encephalopathy is a brain disorder that can have many causes, including infection, inflammation, brain injury, liver failure, drug toxicity, metabolic disease, neurological disorder, and more.

The most common types of encephalopathy are:

Hepatic encephalopathy

Hepatic encephalopathy¹ results from the liver’s inability to eliminate toxins from the body. It corresponds to a complication of a liver disease such as cirrhosis, acute fulminant viral hepatitis or severe liver failure, and is mainly observed in cirrhotic patients. The alteration of liver function causes an accumulation of toxins in the blood, which, upon reaching the brain, causes more or less marked symptoms: at first, the person seems confused, disoriented and exhibits unusual behavior. They may experience mood swings, impaired judgment, and develop mental disorders such as depression, anxiety, and irritability. She suffers from space-time disorientation and an inversion of the day/night rhythm. Other symptoms appear with the progression of the encephalopathy: muscle spasms (myoclonus), asterixis or “flapping tremor” (the patient is unable to keep his wrists stable due to a brief sudden drop in muscle tone of the extensors of the hand), drowsiness, slowing of movements and speech. Without treatment, hepatic encephalopathy can lead to coma and then death of the patient.

Gayet-Wernicke encephalopathy

Mainly observed in alcohol-dependent people, Gayet-Wernicke encephalopathy² is caused by a vitamin B1 deficiency. It manifests itself mainly by oculomotor disorders: either the affected person is unable to keep their eyes fixed due to a disorder in the coordination of their oculomotor muscles (nystagmus), or they suffer, on the contrary, from paralysis of the eyes ( ophthalmoplegia) and double vision (diplopia). She may also have difficulty swallowing, loss of balance, coordination problems (ataxia), short-term memory lapses, and suffer from drowsiness and confusion.

Vascular encephalopathy

Vascular encephalopathy³ is a syndrome secondary to brain lesions of vascular origin such as stroke. These lesions can be due to occlusion of blood vessels (ischemia), inflammation or rupture of the latter. They generally result from the accumulation of cardiovascular and cerebrovascular risk factors (arterial hypertension, smoking, diabetes), and therefore occur more readily in older people. Its manifestations can be varied: headaches, mental confusion, muscle weakness, loss of coordination, vision and speech disorders, impaired memory and concentration.

Hypertensive encephalopathy

Hypertensive encephalopathy⁴ is part of vascular encephalopathies; It is a rare but potentially fatal complication of high blood pressure. It occurs when blood pressure is so high that it damages blood vessels in the brain, causing bleeding and swelling of the brain. Symptoms of hypertensive encephalopathy may include severe headache, vomiting and seizures. This is a medical emergency.

Hypoxic-ischemic encephalopathy

Hypoxic-ischemic encephalopathy⁵ is a rare neonatal disease that refers to brain damage due to too little blood or oxygen supply to the brain. This type of encephalopathy can result from many causes: the placenta did not provide enough oxygen during labor, a blockage in the baby’s umbilical cord, a blood clot in the baby’s brain, an infection… birth, the baby is very pale, his breathing is weak or even absent, he is limp and lethargic… The prognosis is often life threatening. If he survives, the long-term consequences are more or less severe depending on the extent of the brain damage: behavioral disorders, developmental delay, learning difficulties, cognitive impairment, seizures, visual and hearing dysfunction, cerebral palsy.

Metabolic encephalopathy

Metabolic encephalopathy⁶ is a complication that occurs when blood concentrations of certain substances (glucose, sodium, ammonia, etc.) are too high or too low. The symptoms of metabolic encephalopathy depend on the substance involved. For example, hyperglycemia (high blood glucose) can cause mental confusion and seizures, while hyponatremia (low blood sodium) can cause nausea, vomiting and seizures.

Chronic traumatic encephalopathy

Chronic traumatic encephalopathy⁷ is a disease mainly diagnosed in people who have suffered repeated head trauma such as shaken babies, certain athletes who are victims of multiple concussions or even in soldiers exposed to head trauma by blast. Symptoms of chronic traumatic encephalopathy may include cognitive deficits (memory problems, executive function disorders leading to difficulty developing strategies, performing two tasks simultaneously, adapting to unexpected events, staying focused, etc.). ), mood disorders (irritability, depression, despair), tremors, headaches.

Sepsis-associated encephalopathy

Still very often unknown, encephalopathy associated with sepsis⁸ is not, however, a rare clinical situation; it is even very often the cause of cases of confusion observed in intensive care and resuscitation units. It is defined as “diffuse brain dysfunction induced by the systemic response to infection”. The encephalopathy associated with sepsis therefore does not result from a direct infection of the brain; most often it is a complication of a urinary or pulmonary infection.

Bovine spongiform encephalopathy (BSE)

Better known as “mad cow disease”, bovine spongiform encephalopathy was rampant at the end of the 20th century. This degenerative infection of the nervous system of cattle, caused by prions, caused panic when it was transmitted to humans via the consumption of meat products from contaminated animals, causing symptoms similar to those of Creutzfeldt-Jakob disease.

What are the symptoms of encephalopathy?

As we have just seen, the symptoms of encephalopathy are varied, but they can be classified into different groups:

• The trubles of conscience : they range from simple confusion (the person does not know what they are doing, nor where they are, they do not recognize their loved ones…) to coma through lethargy;
• THE motor disorders : they range from simple motor difficulty to complete paralysis
• THE mood disorders : depression, irritability, mood swings…
• THE sensory disorders : tingling at complete anesthesia of a territory
• THE cognitive disorders : memory problems, executive dysfunction, dementia…
• THE behavioral problems : impulsivity, explosiveness, and/or aggression

The signs of encephalopathy actually depend on the disease in question. However, consciousness disorders, mood disorders, behavioral disorders and headaches are frequently found.

How is encephalopathy diagnosed?

The diagnosis of encephalopathy depends on the underlying cause, and diagnostic methods may vary accordingly.

However, the diagnosis is systematically based on a physical examination of the patient which includes questioning about his symptoms, the circumstances of their occurrence, his personal and family history, exposure to potential risk factors for encephalopathy and the existence of possible comorbidities.

The doctor can then carry out a neurological examination comprehensive to assess the patient’s brain functions, including coordination, vision, speech, memory, reasoning and reflexes.

And bilan sanguin must systematically be carried out to look for metabolic abnormalities, infections, abnormalities of liver or kidney function, or electrolyte imbalances…