Neuroleptic malignant syndrome: symptoms and causes

The use of antipsychotic medication within the realm of mental health is one of the most used when intervening in a patient with some type of disorder or disease in which there is a series of psychotic symptoms. Likewise, its prescription for mood disorders and personality disorders.

However, sometimes the consumption of this antipsychotic medication is associated with certain side effects, which interfere with the proper functioning of the central nervous system. A rare disease associated with the effects of this medication is neuroleptic malignant syndrome., which can lead to numerous complications in the body and even death.

Definition of neuroleptic malignant syndrome

Neuroleptic malignant syndrome is a rare condition caused by an adverse response to the effects of antipsychotic medication first, or other associated drugs second. This response may be caused by the action of the drug or by its abrupt withdrawal.

This unusual syndrome is distinguished by causing complications such as dysautonomia, elevated temperature body, changes in the state of consciousness and even to produce death in those cases in which there is no intervention on time.

This syndrome tends to affect to a greater extent young men and women who are administered a prolonged-release neuroleptic. As well as in Parkinson's patients in whom the dose is moderated or the usual dopaminergic treatment is canceled.

Symptoms

Symptoms associated with neuroleptic malignant syndrome tend to appear during the first three days after the patient begins treatment.. These symptoms begin with the appearance of a sensation of anxiety which precedes alterations in the state of consciousness.

The most characteristic manifestations of this syndrome are hyperthermia and muscular rigidity. As for hyperthermia, the person can suffer fevers between 38.5º and more than 40º, this being considered an essential requirement for the diagnosis of this condition.

On the other hand, muscle stiffness can cause complications such as dysarthria or difficulty articulating sounds, swallowing problems and excessive saliva secretion. As well as hypoventilation and suffocation or breathing difficulties.

Other symptoms found in a person suffering from this syndrome include:

• Tachycardia
• Diaphoresis or excessive sweating
• Skin paleness
• Incontinence
• Hypertension
• Cloudiness, dullness, or coma
• Impaired reflexes
• Generalized seizures
• Tremors
• Kidney failure

Causes of this syndrome

The main theories within the study of neuroleptic malignant syndrome point to the different effects that neuroleptics can have on the correct articulation of the system pyramidal and in the hypothalamus.

The hypothesis most supported by the scientific and medical community proposes that a decrease in activity central nervous system dopaminergic activity may interfere with the proper functioning of the basal ganglia and of the hypothalamus.

• The basis of this theory is based on two justifications:
• The syndrome originates after the administration of antidopaminergic medication
• Dopamine is a neurotransmitter that mediates pathologies of the central nervous system that include alterations in muscle tone and thermoregulation

In addition, other symptoms such as muscle stiffness, slowness of movement, muteness and jerking or palpitations are likely to be caused by an instability or alteration of the system dopaminergic in the hypothalamus.

Finally, it has been observed that the administration of agonist drugs of the dopamine, such as bromocriptine, are effective in reducing the symptoms associated with neuroleptic malignant syndrome.

Diagnosis and differential diagnosis

There are a number of firmly established criteria for the diagnosis of this disorder. These criteria are classified into major and minor and the person must meet at least the three major criteria, or two major and four minor.

Major criteria

The major criteria include hyperthermia, muscle tension, increased creatine kinase (CPK) enzyme.

Minor criteria

Tachycardias, abnormal blood pressure, increased respiratory rate, changes in consciousness, sweating, and leukocytosis.

However, there are discrepancies within the medical community when it comes to noting increased creatine kinase (CPK) as a criterion of major importance. From this point of view, a series of alternative diagnostic criteria have been designed according to which for an effective diagnosis the person must suffer from these three symptoms:

• Hyperthermia or elevation of temperature above 37.5º, with no other pathology that justifies it.
• Severe extrapyramidal manifestations such as muscle tension, dysphagia, excessive secretion of saliva, alterations in eye movement, arching of the spine or grinding of the teeth.
• Autonomic nervous system depression

Since the mortality potential of neuroleptic malignant syndrome is considerably high, it is necessary to rule out any other type of condition or disease, as well as current, as quickly as possible.

For the differential diagnosis, the possibility that the person suffers from any of the following alterations must be ruled out:

Symptoms caused by the development of an infection in the central nervous system

• Lethal catatonia
• Malignant hyperthermia produced by anesthetic medication or muscle relaxants
• Heatstroke
• Atropinism or poisoning from anticholinergic medication overdose

Treatment

In cases where the syndrome is caused by the effects of neuroleptics, it will be necessary, first of all, to withdraw the medication and provide care for support and assistance both to lower body temperature and to reverse hypotension through the restoration of fluids and the use of medications vasoactive.

In most cases in which the syndrome is detected early supportive intervention is effective and sufficient for the syndrome to subside and lead the patient to recovery without any type of sequelae.

• The standard medication used to treat neuroleptic malignant syndrome includes:
• Anticholinergic drugs to treat extrapyramidal symptoms.
• Dantrolene sodium to relax the muscles and eliminate muscle tension
• Benzodiazepines to reduce anxiety and lower levels of agitation
• Clozapine to restore neuroleptic medication

Prognosis and possible complications

The moment the medication is discontinued and treatment for the neuroleptic syndrome is started malignant, the evolution of symptoms should be positive, that is, the patient should improve progressively.

However, there are a series of relatively frequent complications that could make recovery difficult. These difficulties include:

• Renal insufficiency
• Respiratory failure or pulmonary embolism
• Setbacks such as liver failure, heart failure, or seizures

Despite the severity of symptoms and possible complications the person can overcome the disease as long as it is treated in time. In the opposite case, the probability of death increases considerably, being the causes of most common deaths: heart failure, pneumonia, pulmonary embolism, sepsis and failure hepatorenal.