Narcolepsy

NARCOLEPSY, narcolepsia (from Greek narke-numbness and lepsis-attack), a disease described by Gelineau; the first observation belongs to Westphal (1877). The concept of narcolepsy is defined by two main signs: 1) attacks of sleepiness and 2) a peculiar condition of patients during strong emotional experiences. Attacks of sleepiness are difficult to overcome, brief (usually lasting 1-5-10 minutes, sometimes longer), occur several times a day, and in exceptional cases up to 100 times. Usually before an attack, patients complain of a feeling of heaviness in the head, general weakness. The attack occurs most easily in an environment favorable to normal sleep (absence of external irritants, comfortable position, etc.). In a number of cases, certain hours of the day are noted during which the attack occurs. The patient can overcome the attack of sleepiness, however this increases the general weakness, and the attack still occurs with even greater force. Attacks also occur suddenly and in inconvenient situations: while walking, eating, etc. The patient's condition during an attack of sleepiness resembles normal sleep of varying intensity, sometimes with dreams. During an attack of sleepiness, the patient generally maintains their body position. The patient wakes up on their own. It is easy to awaken them; it is sufficient to touch them. After an attack of sleepiness, patients feel refreshed. The second symptom, so-called cataplexy (synonyms: affective atonia, tonus blockade), is observed under the influence of emotional experiences, most often during laughter. In severe cases, patients fall as if cut down, being unable to speak or perform voluntary movements. In mild cases - weakness in the limbs, neck muscles. Sometimes during an attack of cataplexia, involuntary twitching in various muscle groups is noted, mainly in facial muscles. The attack is brief, not longer than 1 minute. Consciousness is preserved during the attack. On objective examination, hypotonia, absence of tendon reflexes, in one observation (Wilson) - appearance of the Babinski reflex; the pupillary reaction to light is preserved. Sometimes as an equivalent of cataplexia upon awakening from nocturnal sleep, attacks are observed, expressed in the inability for some time to perform voluntary movements. Attacks of sleepiness and attacks of cataplexia are symptoms intimately connected with each other. Usually in patients at the beginning of the disease, attacks of sleepiness appear, and then after some time - cataplexia; in some cases - the reverse relationship. Sometimes there are only attacks of sleepiness. Isolated attacks of cataplexia as a rule are not observed, the existing individual observations were not followed for a sufficiently long time. The presence of the indicated signs in the absence of symptoms of organic lesions of the central nervous system defines the concept of 'essential' N. (Redlich). N. usually begins between the ages of 10 and 20, rarely later; it has a chronic course: cases have been traced with duration of about 20 and more years. In some cases, N. has an indistinct character, consequently patients view their disease as a peculiar curiosity and adapt to this or that work. In other cases, the significant frequency of attacks of sleepiness and the occurrence of attacks of cataplexia under the influence of minor emotional experiences make the patient disabled. The etiology of the disease is little known. Men get sick significantly more often than women (ratio 6:1). In the anamnesis of patients, sometimes skull trauma, severe overexertion, exhausting infections are noted. In individual cases, there was direct heredity: in Westphal's observation - mother and son, in Tkachev's observation in the family there were twelve diseases (attacks only in the form of sleepiness) in four generations with a dominant hereditary character. Enelovich in his four cases of N. found a predominance in their families of persons with epileptoid character traits. Redlich associates N. with dysfunction of the endocrine glands, especially with impairment of the pituitary gland. In some cases, acromegalic features, reduced size of the sella turcica were noted. According to Redlich, in a number of cases there is an increased lymphocytosis in the blood. In individual cases, there was enlargement of the thyroid gland. There are observations where attacks of sleepiness appeared only during pregnancy. Objective symptoms of lesions of the central nervous system outside of attacks are not noted. The psyche of patients does not present anything characteristic. In some cases, schizoid, epileptoid character traits, general nervousness, feeblemindedness were noted. The pathogenesis is not clarified. Pathological anatomy is unknown. Various opinions exist. Gelineau considered that the basis of N. is insufficiency of oxidative processes in the central nervous system. Lewenthal explained the attacks by increased excitability of the vasomotor centers of the medulla oblongata. According to Redlich, the basis of N. is a violation of the functional interaction of subcortical centers, namely - the area of the third ventricle (posterior wall) and the adjacent gray matter of the Sylvian aqueduct. Attacks of cataplexia are caused by the sliding of excitation from the thalamus opticus to the underlying centers (regulating tonus). Adie, Braylovsky give explanations of N. from the point of view of Pavlov's teaching on conditioned reflexes. In addition to the so-called 'essential N.', which is apparently an independent disease, in a number of diseases attacks of sleepiness similar to those described above are observed, for example, in brain tumors developing or causing pressure in the area of the third ventricle, basal meningitis, skull trauma and other diseases of the central nervous system with localization in the area of the third ventricle, in diseases of the endocrine glands, especially the pituitary, sexual, thyroid, in autointoxications (azotemia, sugar diabetes). However, as a rule, in symptomatic N., attacks of cataplexia are not observed; only in epidemic encephalitis have a few corresponding observations been described. In differential diagnosis, the so-called narcoleptic form of epilepsy should be kept in mind, in which seizures are observed that externally resemble attacks of sleepiness, but also have other signs of an epileptic seizure (loss of consciousness, amnesia, etc.). Attacks of cataplexia resemble epileptic seizures that express themselves in sudden falling (Kent), especially those described by Oppenheim as epileptic seizures at the height of laughter. The distinguishing signs are the above-mentioned symptoms of an epileptic seizure. To some extent, attacks of cataplexia have a similarity with paroxysmal paralysis of Westphal-Leyden; however, despite external similarity, there are great differences: the occurrence of seizures under the influence of emotional experiences and their brevity. In hysteria, attacks of sleepiness differ in significant duration, the presence of stigmata, etc. -- On the question of the essence of N., there is no single opinion. Some authors consider N. as an independent nosological unit, others (Lhermitte, Suk) believe that N. is only a symptom in various diseases, although in some cases the underlying disease cannot be established. Apparently there are more grounds to consider correct the point of view of authors defending the independence of N. -- Treatment in general is unsuccessful. Sometimes improvement was obtained from the use of preparations of the endocrine glands (pituitrin, thyreoidin), hydrotherapy procedures.

P_? Tkachev.