A history of oculogyric crises during the encephalitis lethargica pandemic

A pandemic of what came to be known as encephalitis lethargica spread starting in the winter of 1916-1917 and continued into the 1930s. Neurological after-effects, namely permanent parkinsonian syndromes and various abnormal movements, permanently disabled the survivors of the one or two million victims, often children or young adults. Among them, a small proportion developed a symptom that was little known up to that point and that is currently exceptional: oculogyric crises; that is, a lateralised, dystonic upward movement of the eyes known as a tonic eye fit. This paper proposes a history of the recognition of this symptom, its inclusion in the neurological nosography, and the pathophysiological hypotheses postulated a century ago.

[Encephalitis lethargica. The epidemic at the dawn of neurology]

Lethargic encephalitis is a neurological illness that shows a wide range of symptoms and signs, including neurological and psychiatric spectrum. It presented in an epidemic way, following influaenza relapses. The last relapse started at the beginning of 20th century and it was deeply described by Constantin von Economo. The illness described first in Europe and North America, was described in many others countries including Chile. There were beautiful descriptions by Chilean physicians like Lea-Plaza, Tello, Iturra and Cienfuegos. Their works showed the complexity of the illness like European physicians did too. The etiology is still unknown; however growing evidence about autoinmune aetiology is gaining force with the use of actual medical technology. In this work, we show encephalitis lethargica, focusing in clinical picture, the beauty of medical descriptions that physicians did at this date.

Gabrielle Lévy and the Roussy-Lévy syndrome

In 1934, Gabrielle Lévy died at the age of 48. She became well known for an article she published on a hereditary polyneuropathy in cooperation with Gustav Roussy, resulting in the eponym Roussy-Lévy syndrome. Not much is known about this extraordinary neurologist/neuropathologist. Her family declared that she died from the disease she was studying. She was a pupil of Pierre Marie, with whom she worked at the Salpêtrière in Paris and wrote on war neurology. In cooperation with Marie, she published a number of articles on postencephalitic syndromes, which also became the subject of her 1922 thesis. Three years later, she became associate physician at the Paul-Brousse Hospital in Paris, where the study of brain tumors became one of the subjects of her scientific work. Remarkably, Lévy was first author in a few of her many articles, although Roussy confirmed that she often initiated the study and even wrote the main part. In this article her career is considered in the context of the struggle of women physicians to improve their position during the early-twentieth century. She probably died from a brain tumor or a postencephalitic syndrome.

Evidence for an enterovirus as the cause of encephalitis lethargica

BACKGROUND

The epidemic of encephalitis lethargica (EL), called classical EL, was rampant throughout the world during 1917-1926, affecting half a million persons. The acute phase was lethal for many victims. Post-encephalitic parkinsonism (PEP) affected patients for decades. Our purpose was to investigate the cause of classical EL by studying the few available brain specimens. Cases of PEP and modern EL were also studied. Transmission electron microscopy (TEM) and immunohistochemistry were employed to examine brain from four classical EL cases, two modern EL cases and one PEP case.

METHODS

Standard methods for TEM, immunohistochemistry and RTPCR were applied.

RESULTS

27 nm virus-like particles (VLP) were observed in the cytoplasm and nuclei of midbrain neurons in all classical EL cases studied. Large (50 nm) VLP and 27 nm intranuclear VLP were observed in the modern EL cases and the PEP case. Influenza virus particles were not found. VLP were not observed in the control cases. TEM of cell cultures inoculated with coxsackievirus B4 and poliovirus revealed both small and large intranuclear virus particles and small cytoplasmic particles, similar to the VLP in EL neurons. In the EL brains, nascent VLP were embedded in putative virus factories and on endoplasmic reticulum (ER). The VLP in the cases of classical EL survived, whereas ribosomes underwent autolysis due to the lack of refrigeration and slow formaldehyde fixation of whole brain. The VLP were larger than ribosomes from well preserved brain. Immunohistochemistry of classical EL cases using anti-poliovirus and anti-coxsackievirus B polyclonal antibodies showed significant staining of cytoplasm and nuclei of neurons as well as microglia and neuropil. Purkinje cells were strongly stained.A 97-bp RNA fragment of a unique virus was isolated from brain tissue from acute EL case #91558. Sequence analysis revealed up to 95% identity to multiple human Enteroviruses. Additional cases had Enterovirus positive reactions by real time PCR.

CONCLUSIONS

The data presented here support the hypothesis that the VLP observed in EL tissue is an Enterovirus.

Viral parkinsonism

Parkinson's disease is a debilitating neurological disorder that affects 1-2% of the adult population over 55 years of age. For the vast majority of cases, the etiology of this disorder is unknown, although it is generally accepted that there is a genetic susceptibility to any number of environmental agents. One such agent may be viruses. It has been shown that numerous viruses can enter the nervous system, i.e. they are neurotropic, and induce a number of encephalopathies. One of the secondary consequences of these encephalopathies can be parkinsonism, that is both transient as well as permanent. One of the most highlighted and controversial cases of viral parkinsonism is that which followed the 1918 influenza outbreak and the subsequent induction of von Economo's encephalopathy. In this review, we discuss the neurological sequelae of infection by influenza virus as well as that of other viruses known to induce parkinsonism including Coxsackie, Japanese encephalitis B, St. Louis, West Nile and HIV viruses.

Lack of detection of influenza genes in archived formalin-fixed, paraffin wax-embedded brain samples of encephalitis lethargica patients from 1916 to 1920

A method was developed for detection of influenza genes in formalin-fixed brains of mice that had been experimentally infected with influenza A/NWS/33 (H1N1) virus. Using this technique, messenger ribonucleic acid (mRNA) of the beta-actin gene was detected in eight clinical brain samples from the 1916-1920 outbreak of encephalitis lethargica, showing preservation of particular mRNAs. However, we did not detect influenza nucleotide sequences of M, NP, and NS genes from these same samples. We conclude either that influenza was not the causative agent of encephalitis lethargica or, possibly, that the virus had a hit-and-run mechanism and was no longer present in the brain at the time of death of the patients.

Experimenting on the past: the enigma of von Economo's encephalitis lethargica

Encephalitis lethargica (EL) was a complex and mysterious disease that appeared around the same time as the great influenza pandemic of 1918. The contemporaneous relationship of the 2 diseases led to speculation that they were causally related. Contemporary and subsequent observers conjectured that the influenza virus, directly responsible for the deaths of more than 20 million people, might also have been the cause of EL. A review of the extensive literature by observers of the EL epidemic suggests that most contemporary clinicians, epidemiologists, and pathologists rejected the theory that the 1918 influenza virus was directly responsible for EL. Disappearance of the acute form of EL during the 1920s has precluded direct study of this entity. However, modern molecular biology techniques have made it possible to examine archival tissue samples from victims of the 1918 pandemic in order to detect and study the genetic structure of the killer virus. Similarly, tissue samples from EL victims can now be examined for evidence of infection by the 1918 influenza virus.

Apoptosis in brain and gut tissue of mice fed a seed preparation of the cycad Lepidozamia peroffskyana

Apoptosis (programmed cell death) was identified in histological sections of brain and gut tissue of adult mice fed seed preparations from the cycad Lepidozamia peroffskyana. This form of cell death was also found at high levels in brain tissue from neonatal mice born from a cycad-fed mother. The discovery was made during re-appraisal of archival tissue from a study of toxic properties of L. peroffskyana. Ingestion of appropriately prepared food or medicine derived from another cycad, Cycas circinalis, is thought to be associated with several motor neurone and other neurodegenerative disorders of some Pacific island inhabitants. Apoptosis is cell death under gene control. From the present study, presence of apoptosis in brain tissue after cycad toxicity may provide a link between cycad ingestion and development of neurodegenerative disorders and may provide a novel explanation for localization of some neurodegenerative disorders, as some inhabitants may have a genetic susceptibility to apoptosis induced by cycad toxicity.

Pathological overlap in cases of parkinsonism associated with neurofibrillary tangles. A study of recent cases of postencephalitic parkinsonism and comparison with progressive supranuclear palsy and Guamanian parkinsonism-dementia complex

In recent years a number of patients suffering from long-standing postencephalitic parkinsonism have donated their brains to the United Kingdom Parkinson's Disease Society Brain Bank, in London. In view of the paucity of detailed neuropathological reports of the disease since the 1940s, we have carried out a clinicopathological study of eight recent cases. A spectrum of pathological change was seen, with highly variable involvement of cortical, subcortical and brainstem structures. There was no correlation between severity of disease and severity of pathology. The anatomical distribution of lesions was compared with that seen in progressive supranuclear palsy and Guamanian Parkinson-dementia complex. No definite histological features were identified that could distinguish any of the three disease entities. While the pathogenesis of postencephalitic parkinsonism, progressive supranuclear palsy and Guamanian Parkinson-dementia complex remains unknown, the presence of similar pathologies in these conditions suggests a common disease mechanism, despite the distinctive clinical features.

Is progression in postencephalitic Parkinson's disease late and age-related?

Follow-up data are presented of ten patients with autopsy-proven postencephalitic Parkinson's syndrome (PEP) (mean age at death: 56.0 years) with regard to motor and psychic deterioration over a period of institutional observation between 3 and 30 years. Four patients showed deterioration of their Hoehn-Yahr score of at least one grade. These patients did not differ statistically with respect to age of occurrence of lethargic encephalitis, interval to PEP, age at start of PEP, duration of survival with PEP, and age at death. Motor deterioration in these patients seems to be attributed more to inherent disease progression, rather than to an age-related process. Clinical and pathological evidence for this conclusion is presented.

Does idiopathic parkinsonism in Aberdeen follow intrauterine influenza?

A study is presented which fails to replicate a recent report that peak years of birth of patients later developing Parkinson's disease are related to the influenza pandemics of the period 1890-1930. The years of birth of a whole population cohort of 243 patients suffering from Parkinson's disease examined in Aberdeen in 1983 and reexamined in 1986/7 were compared with deaths due to influenza in the City of Aberdeen in the years 1900-1930. Although a significant peak of Parkinson births (compared with the age profile of the Aberdeen population in 1983) occurred in 1902, there appeared to be no systematic relationship between Parkinson births and influenza deaths. In addition, no season of birth effect could be detected in a comparison with 232 matched controls. The presence of peaks of birth years, for whatever aetiological reason, is of significance to epidemiological studies in that prevalence estimates may be influenced by the year of study relative to these mini-cohorts.

Encephalitis presenting as acute schizophrenia

Three patients developed symptoms suggestive of acute schizophrenia. In each case there were no abnormal neurological findings on admission to hospital. Within a few days clinical evidence of encephalitis became apparent, and appropriate treatment was given. Only one patient made a full recovery.