Akinetic crisis is an acute disorder of motor activity in the form of a sharp difficulty of voluntary movements, developing in Parkinson’s disease. The clinical picture is characterized by oligobradykinesia, hypomimia, dysarthria, plastic increase in muscle tone, dysphagia, vegetative symptoms. Diagnostics includes laboratory tests, MRI, PET, brain SPECT. Complex treatment is carried out, including relief of emergency conditions, elimination of the provoking factor, symptomatic therapy, taking dopaminergic drugs. Additionally, glutamate system blockers, glucocorticosteroids are used.
General information
Akinetic crisis (acute akinesia) is a life-threatening complication of Parkinson’s disease (PD). It refers to urgent conditions that arise as a result of pronounced hypofunction of the dopaminergic system. It was first described in detail in the 80s of the twentieth century in patients during a break in drug therapy. Acute akinesia is a relatively rare phenomenon and occurs in 0.3% of patients with PD, secondary to infectious pathology or other factors. Akinetic crisis is not typical for the early stages of parkinsonism, even with the cancellation of specific therapy for 14 days. Pathology is more often noted in the akinetic-rigid form of the disease.
Causes
Akinetic crisis can be triggered by a number of factors, such as therapeutic manipulations, cancellation of treatment, various diseases that occur against the background of PD. The most common reason is the termination of the necessary treatment by the patient. Other etiofactors are considered to be:
- Changing the treatment regimen. Correction of the therapy, dose, frequency of administration, replacement of the drug can provoke an akinetic crisis.
- Reception of individual pharmaceuticals. Neuroleptics, reserpine, metoclopromide, cinnarizine are able to block dopamine receptors, causing decompensation.
- Diseases of the gastrointestinal tract. Infectious lesions, neoplasms, conditions after intestinal resection, acute and chronic forms of gastroenteritis lead to a disorder of drug absorption. There is a situation similar to stopping taking antiparkinsonian medications.
- Electrolyte disturbances. Sodium balance disorders and their inadequate correction can cause demyelination at the level of the brain bridge, exacerbating dopamine disorders.
- Deep cerebral electrical stimulation. It is used as a method of treating PD. Battery discharge, malfunction of the stimulator, its incorrect programming entail a violation of stimulation, equivalent to the absence of drug treatment.
Pathogenesis
The pathophysiological mechanism of akinetic crisis is unclear. Pathology is not just a reflection of pronounced parkinsonian hypokinesia, but rather a specific condition with unknown risk factors that are not directly related to the stage of the disease, the dosage of medications. One of the main features is the long-term (on average 11 days) immunity to antiparkinsonian drugs.
Presumably, the pathogenesis of the akinetic crisis is based on a temporary blockage of the dopamine system, as a result of which it ceases to respond to treatment, which usually gives a rapid motor effect. In the course of research in 2014, a sharp decrease in the ability of the striatum to presynaptic accumulation of the labeled dopamine transporter during an akinetic crisis, its subsequent slow recovery, was demonstrated.
Symptoms
The development of symptoms is observed in the period from 18 hours to 7 days from the time of termination of treatment, the action of another provoking etiofactor. Typically, a significant increase in hypokinesia and rigidity up to a complete lack of motor activity. Akinetic syndrome is accompanied by signs of autonomic dysfunction: blood pressure lability, tachycardia, rapid breathing, sweating. Urination disorders are characteristic. In some cases, after 72 hours from the development of akinesia, hyperthermia of central genesis occurs, the body temperature rises to 41 ° C.
Consciousness is disturbed. Sopor is often observed, in severe cases — a comatose state. The patient is disoriented in time, the orientation of the personality is preserved. Dysphagia, quiet slurred speech, dysarthria are noted. Myoclonia, generalized convulsive seizures are possible.
Complications
Poorly controlled high hyperthermia combined with dysphagia quickly leads to dehydration. Water-electrolyte disorders occur, the rheological properties of blood change, which leads to thrombosis. Against this background, a pulmonary embolism is likely. In some cases, renal failure is observed. Swallowing disorders are complicated by the ingestion of food into the respiratory tract, the development of asphyxia, aspiration pneumonia. Without timely emergency care, the condition can lead to death.
Diagnostics
When examining a patient, a neurologist reveals oligobradykinesia, an increase in muscle tone according to the plastic type. Adequate assessment of muscle strength is difficult due to a marked decrease in motor function. The sensory sphere remains intact. The level of consciousness can vary from clear to sopor, coma. The face is hypomimic, symmetrical. Dysarthria, dysphagia, reflexes of oral automatism are noted. The list of necessary laboratory examinations for akinetic crisis includes:
- Blood test. It allows you to identify infectious complications, an increase in the number of platelets.
- Biochemical blood analysis. It is necessary for the diagnosis of electrolyte disorders, assessment of kidney function.
- Biochemical analysis of urine. It is crucial in the development of renal failure. It is prescribed together with monitoring of daily diuresis.
- Coagulogram. Hematological analysis allows you to determine the state of the coagulation system, assess the threat of thrombosis.
Confirmation of the diagnosis is carried out after receiving the results of neuroimaging and other additional studies. Instrumental examinations are also necessary for the implementation of differential diagnosis. Patients are recommended:
- Brain MRI. It is characterized by an increase in the intensity of the signal in the cerebral substance of the frontal and parietal localization. Focal changes, mass effect, perifocal edema are not visualized. It is possible to diagnose atrophy of the cortex, the midbrain.
- Cerebral PET. It is necessary to evaluate the absorption of F-DOPA in the striatum. A significant decrease in the background of dopaminergic treatment indicates in favor of an akinetic crisis.
- OFECT. It is carried out in order to visualize the transport of dopamine. Reveals the block of its binding in the striatum.
Differential diagnosis
Akinetic syndrome in PD should be distinguished from motor limitations in other diseases. Myasthenia gravis is characterized by hypokinesia due to muscle weakness, there is no plastic tone. Ptosis is a typical symptom of a myasthenic crisis. A differential diagnosis with catatonic stupor is performed. The latter is characterized by the presence of mental abnormalities in the anamnesis, hypokinesia is caused by inhibition. A distinctive feature is the patient’s resistance to attempts to change the position he has adopted.
Treatment
Primary emergency medical measures are aimed at maintaining vital functions and preventing complications. In case of respiratory disorders, intubation and ventilator connection are performed. Severe dysphagia is an indication for probing, preventing asphyxia.
Infusion therapy is aimed at normalizing the water-electrolyte state. Prevention of thrombosis is carried out by compression bandaging of the lower extremities, the appointment of antithromboxants. In acute renal failure, hemodialysis is performed. If a bacterial infection is suspected, antibiotics are recommended.
Along with emergency therapy, patients need early stimulation of dopamine metabolism. It is necessary to eliminate the trigger that provoked akinesia, to ensure effective absorption of the injected pharmaceuticals. The following groups of drugs are basic in the pharmacotherapy of the akinetic crisis:
- Dopaminergic drugs. They are applied with an increase in the initial dosage. The dose is selected taking into account the genesis of the crisis. Oral administration is carried out in a form dissolved in water. Therapy continues regardless of whether there is an effect, since it can occur after 11 days.
- Glutamate blockers. Hyperactivation of the glutamate system aggravates dopamine decompensation, therefore, its relief is necessary. Intravenous administration is carried out, followed by a transition to the oral form.
- Corticosteroids. In modern neurology, they are considered as an additional therapy for acute akinesia, since glucocorticoid receptors have been found on dopaminergic neurons. The use of glucocorticosteroids in complex therapy makes it possible to achieve an earlier restoration of consciousness, a decrease in body temperature, and normalization of vegetative functions.
Prognosis and prevention
The mortality rate of patients with akinetic crisis is about 15%. Deaths are mainly caused by complicated forms, lack of timely medical care. Timely diagnosis and comprehensive treatment provide a favorable prognosis.
Prevention of akinetic crisis consists in constant intake of dopaminergic drugs without periods of “medicinal holidays”, careful change of medication and dosage correction. Reducing the dose or replacing the drug with its apparent inefficiency should only be done by a doctor. Patients with PD should avoid taking pharmacological agents that block DOPA receptors, and seek medical help in a timely manner for any pathology on the part of the digestive organs.