Encephalitis

“ When the turning movement has developed the diagnosis is generally easy, but it is more difficult during the first period, when encephalitis alone exists; or at least, it is very difficult at this period to discover whether the symptoms are attributable to encephalitis, meningoencephalitis, cœnurosis, tuberculosis, or to some injury. ”

“ Treatment. If in exceptional cases slaughter is objected to, setons and blisters may be applied to the poll or the parotid region, or the parts may be enveloped in ice bags or compresses of iced water frequently renewed.
ENCEPHALITIS. Encephalitis, i.e., inflammation of the cerebral substance, is very closely allied to meningitis; in a great number of cases meningitis and encephalitis co-exist. In other cases encephalitis may be found apart from meningitis, and vice versâ. Moreover, many of the symptoms of meningitis are to be found in cases of encephalitis. ”

“ The symptoms of uncomplicated meningitis on the one hand and encephalitis on the other are rarely seen, the disease usually implicating more or less both brain and meninges, in a common inflammation or the symptoms of the one involving those of the other through proximity or interdependence of function. And yet in traumatic lesions of the cranial walls, the symptoms may be those of pure meningitis, and in thrombosis, embolism or parasitism of the brain, and in certain tumors they may be those of simple encephalitis. ”

“ Acute encephalitis may lapse into the chronic form and then assumes the symptoms of this disease. Cases that come on slowly and imperceptibly appear at times to be hereditary, as might be expected from the fact that it usually goes with a lymphatic temperament. The conditions which cause cerebral or meningeal hyperæmia in chronic form conduce to the affection. Injuries to the cranial vault from traumatism or disease are infrequent causes. ”

“ When encephalitis occurs, it is usually an acute symptom, and often develops before paralysis is set up, but as a rule is preceded by a period of persistent headache, such headache being invariably temporal or occipital. ”

“ Hemorrhagic encephalitis appears to occur more frequently after the second injection than after the first, and according to Thibierge may be especially suspected in subjects who after the first injection present much fever, congestion of face, and cutaneous eruptions. ”

“ The second form of cerebral inflammation is marked by the formation of the ordinary fluid products of acute inflammation in other organs of the body; this is the suppurative form, usually spoken of as abscess of the brain.
In addition to these two generally recognized inflammatory affections there are a number of rare diseases which are regarded by excellent authority as also of that character. The vaguely-used term acute encephalitis has been recently reapplied with distinct limitations to an acute affection of children by Strümpell. ”

“ Sometimes the neurosyphilitic process rises as if by a regular process of siege from spinal nerve-root to spinal nerve-root (tabes dorsalis and diffuse neurosyphilis) . Again, the nervous system is taken by storm, as it were (disseminated encephalitis) . Very frequently the neurosyphilis is simply an indirect effect of blood-vessel disease, and huge masses of tissue are scooped out in necrosis with dependent secondary degenerations; and later the extinct lesions of vascular origin may or may not betray evidence of their syphilitic origin. ”

“ He concludes that the outbreak of encephalitis either antedated the pandemic of influenza of 1918, or that the two diseases more or less overlapped; that is, although probably quite by accident, they prevailed concurrently. He prefers for the time being at least to regard them as independent diseases.
Crookshank believes that encephalitis lethargica is a distinct disease, but that it occurs frequently as an antecedent of or coincident with influenza, together with increase in the existence of poliomyelitis and certain other diseases. ”

“ Embolisms, hemorrhages, cerebral effusions, more or less diffuse encephalitis from an injury to the head, sometimes give rise to the suspicion of general paralysis, until it is found that its characteristic progressive symptoms do not appear, but chiefly when the history of the case has not been definitely ascertained, or when the usual symptoms of those conditions are not well marked. ”

“ In other cases the tumor is attended by paroxysms of vertigo, or indications of hyperæmia or meningitis, which will last for several days and gradually subside. It is reasonable to suppose that the tumors are largely the result of such recurrent attacks of encephalitis, and are no less the cause of their recurrence. The 130intervals of temporary recovery correspond to the subsidence of hyperæmia and the reabsorption of the liquid portion of the exudate. The manifestations during an access correspond directly to those met with in encephalitis. ”

“ The cerebral excitement that sometimes appears in influenza is really an encephalitis complication, but its specific cause is recognized in the local prevalence of the infectious disorder, and the inflammatory or catarrhal condition of the mucous membranes. ”

“ Diagnosis. The condition is often confused with meningitis, and the mistake is not serious, because meningitis and encephalitis frequently accompany one another.
Prognosis. The prognosis must be regarded as fatal. The patients very seldom recover, and there is no reason for keeping them alive.
Treatment. Here, again, blisters may be applied to the upper extremity of the neck, or setons may be passed. Cooling applications to the cranial region have also been suggested. None of these methods produces more than a temporary palliative effect. ”

“ In the examination of several brains of persons who have died from lead encephalitis, microscopic sections of the brain have shown signs of hæmorrhages which must have taken place some considerable time prior to death, and were no doubt associated with the headache that had been complained of for some time previously, before the onset of the fatal illness. (See Plate III.) Persistent headache occurring in a lead-worker should always be regarded with grave suspicion, and such a case should be treated on the assumption that it is an early case of lead encephalitis. ”

“ DISEASES OF THE NERVOUS SYSTEM Encephalitis, Inflammation of the Brain This disease may arise from internal causes, but more frequently from sun-stroke, blows upon the head, too plentiful food, etc.
Symptoms.—The animal ceases to eat; hangs its ears and head, which are hot to the touch; walks along staggering, unconscious whither it goes; the eyes are bright and red and projected from the head; the air it expires is hot; the breathing short, rapid and accompanied with violent beating of the flanks ”

“ If death has occurred at a later period of the disease, it will be found that, in addition to the redness and engorgement, an exudation of the contents of the blood vessels into the tissues and upon the surfaces of the inflamed parts has supervened. If the case has been one of encephalitis, there will usually be found more or less watery fluid in the ventricles (natural cavities in the brain) , in the subarachnoid space, and a serous exudation between the convolutions and interstitial spaces of the gray matter under the membranes of the brain. The quantity of fluid varies in different cases. ”

“ Inflammation may, however, exist in the center of the great nerve masses—the cerebrum, cerebellum, pons Varolii, or medulla at the base of the brain—without involving the surface. When, therefore, inflammation invades the brain and its enveloping membranes it is properly called encephalitis; when the membranes alone are affected it is called meningitis, or the brain substance alone cerebritis. Since all the conditions merge into one another and can scarcely be recognized separately during the life of the animal, they may here be considered together. ”

“ Syphilitic new growths, endarteritis, and meningitis may so far improve from the use of mercury or the iodide of potassium as to end in an apparent cure, but in those cases the symptoms are not so marked as to make an exact diagnosis always possible. A distinct syphilitic cachexia is presumptive evidence of syphilitic encephalitis when there is doubt whether the syphilis is the cause or the diathesis.
Profound melancholia is not so often as varying gloom or moderate despondency a symptom of general paralysis. ”

“ The serum W. R. was positive; the fluid tests were negative.
An extraordinary case is given in some detail in which Neurosyphilis in the form termed Disseminated Encephalitis [83] proved fatal within seven months of the initial infection.
We have frequently mentioned the classical assumption that paretic neurosyphilis (“general paresis”) is a fatal disease. Some have suggested that there is another form clinically almost identical with general paresis except that it pursues a long course and the suggestion has been made that these cases be termed pseudoparesis. ”

“ Yellow fever - mosquito-borne viral disease; severity ranges from influenza-like symptoms to severe hepatitis and hemorrhagic fever; occurs only in tropical South America and sub-Saharan Africa, where most cases are reported; fatality rate is less than 20%.
Japanese Encephalitis - mosquito-borne (Culex tritaeniorhynchus) viral disease associated with rural areas in Asia; acute encephalitis can progress to paralysis, coma, and death; fatality rates 30%. ”

“ During the years of scarcity, from 1528 to 1534, it excited general surprise that malignant fevers, more especially the plague, petechial fever, and encephalitis, which in the individual accounts we can seldom sufficiently distinguish from each other, were constantly recurring, and, creeping slowly as they did from place to place, had no sooner finished their wandering visitations of whole districts of country, than they again made their appearance where they had broken out in former years [417] . ”

“ Cœnurosis with diffuse parasitic encephalitis often remains unrecognised, the animals being regarded as affected with epizootic meningitis of unknown cause or septic intoxication, and when they die the owners are ignorant as to the cause of death. The stage corresponding to turn-sick, which is an advanced phase of the disease, is only seen in animals which have been infested to a slight extent, and in which three or four parasites only, sometimes only one, have attained the brain and developed there. ”

“ A fever, which persists for up to 5 days, essentially coincides with the development of a cell-free viremia and vesicular lesions. The peak viremia occurs 2-4 days postexposure and persists for about 7 days. The virus persists for at least 7 days in the tissues of the snout, tongue, coronary band, tonsil, cardiac muscle, and central nervous system. The stratum spinosum is the primary site of viral replication in the epithelium. A nonsuppurative meningoencephalitis most frequently occurs in the cerebrum, thalamus, brain stem, and olfactory lobes. ”

“ Extravagant delusions of wealth were associated with a fear of being killed.
The autopsy showed little save chronic myocarditis with brown atrophy, calcification of part of thyroid, non-united fracture of neck of left femur, moderate coronary arteriosclerosis. The brain was abnormally soft (some of the larger intracortical vessels showed plugs of leucocytes possibly indicating an early encephalitis—Bacillus cold and a Gram-staining bacillus were cultivated from the cerebrospinal fluid.) ”

“ Thus we have cerebral abscess in pyæmia, strangles and omphalitis, and cerebral 99congestions and inflammation in canine distemper, equine contagious pneumonia, laminitis, and angina.
Among mineral poisons, lead is notorious as a cause of acute cerebral disorder often leading to inflammation. Other mineral poisons like arsenic and phosphorus may lead to encephalitis symptomatic of gastro intestinal irritation, or caused by the toxic products of indigestion. ”

“ Exudate in pia mater—mononucleosis.
2. Superficial (subpial) cellular reaction of neuroglia tissue (expanded cell bodies) .
3. Cellular gliosis of deeper layers of cortex. Apparent increase in capillary supply, possibly relative to loss of neural elements.
Case 57. Neurosyphilis (“disseminated syphilitic encephalitis” of A. M. Barrett) , fatal seven months from initial infection. (Photographs by A. M. Barrett.) ”

“ NOS G04 Encephalitis, myelitis and encephalomyelitis Includes acute ascending myelitis meningoencephalitis meningomyelitis Excludes1: encephalopathy NOS (G93.40) Excludes2: acute transverse myelitis (G37.3-) alcoholic encephalopathy (G31.2) benign myalgic encephalomyelitis (G93.3) multiple sclerosis (G35) subacute necrotizing myelitis (G37.4) toxic encephalitis (G92) toxic encephalopathy (G92) G04.0 Acute disseminated encephalitis and encephalomyelitis (ADEM) Excludes1: acute necrotizing hemorrhagic encephalopathy (G04.3-) G04. ”

“ The investigations which have been made justify the statement that each infectious disease is due to a specific—i. e., distinct—micro-organism. There are, however, certain infectious diseases which physicians formerly supposed to be distinct, and to which specific names are given which are now known to be due to one and the same infectious agent or germ. Thus puerperal fever and erysipelas are now recognized as being caused by the same germ, the germ which is the usual cause of pneumonia is also the cause of a considerable proportion of the cases of cerebro-spinal meningitis, etc. ”