The prodromal phenomena, which generally
make an abrupt appearance a few days or, very
rarely, a few weeks before the onset of the
disease, consist of general discomfort,
lassitude, seediness, shivering, headache,
occasionally vertigo and vomiting. The
temperature is generally only a little raised to
slightly above 98.6° F., but in some cases
may rise above 1O2.2° F. Graver catarrhal
affections of the airpassages are practically
never present, though c1oe examination reveals
in most cases a slight pharyigitis. Very soon
this, influenza-like prodromal stage is
succeeded by a certain somnolence; the patient
is dazed and confused, and may (but not
invariably) show at the same time phenomena of
slight meningeal irritation, such as
sensitiveness of the skull to percussion, a
trace of stiffness of the neck and Kernig's
sign, slight pains on compression of the
eyeballs, frequent yawning, and sometimes
also trismus and singultus. This slight
meningism is used by the virus, and can be
anatomically proved to be a very slight
inflammatory irritation of the meninges by the
infectious process. The headache may in rare
cases be more intense, and pains in the limbs
may also occur. These prodromal phenomena are
usually of very moderate degree in the
somnolent-ophthalmoplegic form and very rarely
reach an alarming intensity. This is more
commonly met with in the hyperkinetic syndrome,
as we shall see in discussing the latter.
Within the next few days somnolence begins
to predominate. If ,slight signs of meningeal
irritation have existed, they disappear
gradually or at least remain stationary, so as
to play a subsidiary role compared with the new
symptoms which now become more prominent and
frequently lead to a revision of the mistaken
diagnosis of an incipient meningitis. In the now
increasing somnolence one often observes that
the patients, left to themselves, fall asleep in
the act of sitting and standing, and even while
walking, or during meals, with all signs of
tiredness and yawning, go to sleep with
food actually in the mouth. They have the
appearance of being in a light slumber or
sometimes in deep sleep, with typical
respiration, even snoring. If aroused, they wake
up quickly and completely, are orientated and
fully conscious, and can reply sensibly to
questioning; they are fully aware of the
situation, carry out all requests promptly, get
up if told to do so and walk about, but, left to
themselves, soon drop back to sleep.
This kind of sleep therefore bears a
deceptive resemblance to normal sleep. In the
mildest cases of the disease, which soon recover
spontaneously, this symptom soon tends to
disappear; a quite slight encephalitis of such
nature is often mistaken for a physiological
reaction to an actual or imaginary preceding
over-exertion. In severe cases, however, this
somnolence, which recurs for periods of hours,
days, or even longer, gradually progresses
towards more or less permanent sleep, out of
which at first it is still possible to rouse the
patients, for instance for meals or other
necessary functions. Sleep in this form may last
for weeks or even months, but frequently deepens
to a state of most intense sopor or even a
comatose condition, which may terminate fatally
after some days or weeks. In case of recovery,
an increased need of sleep or occasionally some
other disturbance of the sleep function often
persists for months after the acute affection
itself. One might be inclined to look upon the
somnolence as a result of the rise of
temperature or of the toxic component (as in
influenza), or of cerebral pressure, were it not
that experience teaches us that somnolence may
be present in encephalitis lethargica without
rise of temperature and without cerebral
pressure, and is repeatedly found, in quite
slight caes as the only well-marked symptom. The
consequence is that we must look for other
causes of this somnolence.
p 50-52
Monosymptomatic form.
I have just indicated when discussing the
neuritic forms how it is practically impossible
in considering an individual case, especially at
the time of an epidemic, to exclude encephalitis
as the source of origin. This applies also to
other isolated pathological manifestations.
During the encephalitis epidemic I repeatedly
saw cases which showed no other symptom than,
for instance, trismus, which at first suggested
tetanus, but, on account of its transitory
character, had to be interpreted as probably
monosymptomatic encephalitis, especially as
trismus in some other cases at that time was
associated with definite encephalitic symptoms.
Similarly, sporadic chorea or hemithorea without
accompanying symptoms may represent a
monosymptomatic encephalitis On investigating
the previous history of possibly
post-encephalitic-diseases it is therefore
always advisable to inquire very closely indeed
iiffo such possibilities and signs of a masked
primary affection. During epidemics of
encephalitis we were able to observe different
monosymptomatic disturbances in otherwise
healthy people, such as varied respiratory
complaints, dyspnoea, tachypnoea, asymmetrical
respiration, &c.; besides pathological
yawning, compulsive masticating and
clucking of lips and tongue, some clonic
phenomena, &c.
The most common of these monosymptomatic
forms is singultus or hiccup. I have already
said that it may be accidentally met with as an
accompanying symptom in the most varied forms of
encephalitis lethargica. In the hyperkinetic
forms it has been interpreted as myoclonus of
the diaphragm; whether this view applies also to
these sporadic cases, where there are no other
myoclonisms present or whether we should not
look in this instance on the hiccup as the
result of a state of phrenic nuclear
stimulation, remains an open question for the
present. Sporadically, singultus has sometimes
been observed as an incipient symptom of
encephalitis lethargica. A few weeks before the
outbreak of the serious hyperkinetic epidemic of
encephalitis in Vienna in 1920 there happened to
be a small epidemic of singultus in that city,
which attacked a great number of people and
which, after a troublesome duration of hours and
sometimes of days, without any other symptoms,
vanished as suddenly as it had appeared. Such
singultus epidemics have also been observed at
various times in Paris and at other places
during periods of encephalitis lethargica and
influenza epidemics. MacNalty described an
epidemic of hiccup in England of as recent
appearance as the first two months of 1929.
(Rosenow has cultivated a streptococcus from the
nasal and pharyngeal mucous discharges of such
patients and claimed to have obtained similar
diaphragmatic convulsions in animals on
inoculation with that germ.)
It is still doubtful whether these singultus
epidemics may be regarded as abortive and
rudimentary epidemics of encephalitis (formes
frustes). It has properly been pointed out
(Sicard) that of the great number of people
attacked during these epidemics of singultus
none has been observed-apart from exceptional
cases (Neel)- to suffer afterwards from a
post-encephalitic disease. Measured by the
frequent occurrence of sequelae this
circumstance makes the identity of the two
affections in some degree doubtful. On the other
hand this should not be regarded as an absolute
criterion; I would merely recall that the first
epidemic of encephalitis lethargica which I
described was practically free from sequelae.
Also, if one should feel inclined to postulate a
different virus as the cause of the singultus,
the fact of the synchronization of outbreaks of
encephalitis and of epidemic singultus and their
simultaneous disappearance should be borne in
mind. This points to a condition of epidemic
'neighbourhood'. If a separate virus for these
two diseases be assumed, one should at least
postulate a similarity or identity of those
secondary external conditions which, in the
opinion of Dorr, are instrumental with regard to
the outbreak of an epidemic. The literature of
singultus epiderniø is fairly voluminous.
Sicard described it as paraencephalitis. Redlich
is certainly right in assuming that during these
last years, from reasons unknown, we have
witnessed the outbreak of quite a series of
neurotropic germs, and that it is a mistake to
reckon all these cases under the heading of
encephalitis. I share this opinion and hold that
Cruchet commits this mistake in his last
publication, when he tries to refer to his old
observations as cases of encephalitis
lethargica, which for the most part they are
not.
Since the discovery of lenticular
degeneration by Wilson we attribute this kind of
static rigidity, tremor, and the whole of the
complex of symptoms surrounding paralysis
agitans, the choreiform and athetotic movements,
and the so-called extra-pyramidal disturbances
of locomotion, such as we find so well developed
in Parkinsonism, to affections of the basal
ganglia, the nucleus caudatus, and nucleus
lentiformis, in more recent times also of the
subthalamic nuclei and the substantia nigra. We
speak also of the striatal or, better, with
regard to the last-named localizations,
extrapyramidal complex of symptoms. Post-mortem
examination of the cases which die of
Parinsonism tells largely in favour of this
supposition. In this region of the basal grey
cerebral masses there is probably located a
series of centres which exercise an influence on
progression of movements, rhythm, volume of
progressive movements, timing, and many other
processes, quite independently of the question
whether these movements are of a mainly
automatic nature or are originally volitional
and executed under the control of attention and
have only later become partly automatic.
This points to some direct influence acting
upon the course (so far as it is automatic) of
volitional acts and in its further
interpretation to a possible indirect action on
purely mental processes. Under the heading of
this group of disturbances I should feel
inclined to classify quite a number of phenomena
which, as post-encephalitic phenomena, are
generally associated with other signs of
Parkinsonism or accompany a fully developed
state of Parkinsonism, but which occasionally
may occur as a separate syndrome of sequelae by
themselves or in common with other quite
different post-encephalitic symptoms even
without Parkinsonism. One might describe them as
disturbance of the automatisms. Many years ago I
proved the existence in the substantia nigra of
an important shuntingstation for automatic
rhythm of movement and progression of acts of
mastication and swallowing. Now in
post-encephalitic disturbances we repeatedly
find a rhythmic repetition or tic-like
recurrence of movemente of mastication and
swallowing or convulsive yawning and
sounds of clucking and sucking. But other tics
and compulsive movements occur as well,
particularly in those groups of muscles in which
the nonencephalitic tics locate themselves by
preference and not, as might be expected, in
those muscles which are generally affected by
the acute encephalitic hyperkinesis (Wagner y.
Jauregg). We see therefore blepharospasms,
mimetictics, tics of clucking and hissing, also
torticollis and tics of the upper and lower
extremities, but we find also fits of selling
and yawning, &c. Often these tics may
be influenced by the position of the body, for
instance they cease on lying down; but not
infrequently they may be influenced by
suggestion, for instance by hypnosis, or may be
suppressed for some time by will-power. But
unfortunately these improvements by suggestion
or education do not last for long. To this group
probably belong also the respiratory
disturbances which we often find in
post-encephalitic patients (Vincent and Bernard,
Babinski and Charpentier, van Bogaert, S. E.
Jelliffe, W. A. Smith, Westphal, Stem, Hess).
The respiratory disturbances of the acute phase
have already been discussed on p. 50.
Relatively speaking, the most frequent
disturbances are attacks of hyperpnoea with
forced expiration. Often these attacks lead to
quite grotesque paroxysms with the oddest
accompanying movements, which the patients feel
to be compulsive. A patient in this condition
opened his mouth wide, twisted his trunk and
arms backwards in the most extreme fashion,
stamped at the same time with his feet, and
uttered a snorting sound. On being questioned he
did not perhaps give dyspnoea as the reason f
these weird acts, but said: 'Well, I must twist
my arms that way.' As a matter of fact there is
actually as a rule no dyspnoea present.
Sometimes there seems to be a diminished amount
of bicarbonate in the blood-serum (Happ and
Mason), but at other times this is not observed.
Quite occasionally, however, genuine dyspnoeic
attacks occur (Bériel). But this seems
rather a disturbance of rhythm and 'progression
of movement' and volume of movement in proxintai
centres, whereby the automatism of the distal
respiratory centre loses part of its proper
regulation through the absence of central
inhibition. These attacks may be released by
emotion (Insabato), but at other times they may
themselves cause states of fear (Kennedy).
Hyperpnoea may also exist as a condition of
some duration, sometimes in conjunction with
peculiar accompanying movements, for instance,
contractions of the biceps with every breath.
The hyperpnoea may be accompanied by tetanoid
symptoms as a result of hyperventilation (Barker
and Sprunt), also bradypnoea, apnoea, irregular
respirations, nervous cough, spastic cough,
sighing, tics of respiration, &c., occur.
These purely nervous functional disturbances are
primarily caused by organic lesions. They can
bring sensations or complexes of sensations and
emotions in their wake, which on the one hand
may be primary, that is, of the same generic
order as the accompanying movements so
frequently seen and caused by the same
disturbance as the disturbanèe of
motility itself, or on the other hand possibly
secondary. Thus, for instance, appreciation of
the position in which he is placed may cause
emotions of fear or embarrassment in a patient.
Certain mental fixations may therefore lastingly
associate themselves with these motor
disturbances and lend them a neurotic imprint;
this neurotic element asserts itself (Jelliffe)
in dreams or otherwise in the behaviour of the
patiénts. The neurotic aspect of these
patients is then still further enhanced by the
apparent possibility, mentioned above, of
influencing Or even suppresing.tieir tics with
their associated mental (primary as well as
secondary) symptoms by suggestion.
Not only is the order of the movements of
respiration repeatedly disturbed, but one finds
repeatedly in post-encephalitics, when the
attention is directed to it, more intricate
motor disturbances, as, for instance,
disturbances of writing reminiscent of writer's
cramp, and also micrographia (Bériel,
Souques, Gerstmann and Schilder), that is to
say, the patients begin to write in the normal
way, then the characters become gradually
smaller, tifi in the end they become minute and
indecipherable and the hand comes to a
cramp-like standstill. On making patients read
with a loud voice similar odd disturbances are
found; thus one of our patients, after a few
minutes' reading, began to increase the speed
gradually to such a degree that articulation
altogether, failed and ended suddenly in an
indistinct mutter. A certain resemblance to pro-
and retropulsion in walking is obvious.
Sometimes also the last syllables of a sentence
are repeated, chorus-like (so-called
logoclonia). A pathological disturbance of an
opposite nature may also occur. Sometimes
patients are unable to iterrupt an action once
begun; when, for instance, they read, they carry
on till one actually takes the book away from
them; a passive movement is frequently repeated
for a long time (Mayer-Gross and Steiner).
Encéphalite léthargique
Cruchet, Moutier, Calmettes Soc méd hop
Paris 27 avril 1917
