ADEM: literature review and case report of acute psychosis presentation

Recurrent Acute Disseminated Encephalomyelitis Presenting as Conus Medullaris Syndrome: A Case Report

Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disorder that typically follows an infection or recent vaccination. Symptoms such as encephalopathy and focal neurological deficits appear weeks after the initial illness, leading to swift and progressive neurological decline. While ADEM in the brain has been well documented, reports of ADEM, specifically in the spinal cord, are relatively limited. A 58-year-old male presented with rapidly progressive bilateral lower extremity tingling, numbness, and mild gait disturbance approximately two days prior to visiting the emergency room. Spinal magnetic resonance imaging revealed a diffuse, longitudinal, high-signal lesion with mild enlargement of the conus and proximal cauda equina. The lesions were predominantly localized in the distal conus and cauda equina, and serial electrodiagnostic studies showed that the lesions progressed toward the proximal conus in tandem with symptom evolution and lacked clear lateralization. The patient was subsequently treated with high-dose steroids for seven days (intravenous methylprednisolone, 1 mg/kg). The patient's lower extremity weakness gradually improved and he was able to walk independently under supervision three weeks after symptom onset. In this case of spinal ADEM in a middle-aged adult, high-dose steroid treatment led to outstanding neurological recovery from both the initial occurrence and subsequent attacks.

Psychosis Caused by a Somatic Condition: How to Make the Diagnosis? A Systematic Literature Review

BACKGROUND

First episode of psychosis (FEP) is a clinical condition that usually occurs during adolescence or early adulthood and is often a sign of a future psychiatric disease. However, these symptoms are not specific, and psychosis can be caused by a physical disease in at least 5% of cases. Timely detection of these diseases, the first signs of which may appear in childhood, is of particular importance, as a curable treatment exists in most cases. However, there is no consensus in academic societies to offer recommendations for a comprehensive medical assessment to eliminate somatic causes.

METHODS

We conducted a systematic literature search using a two-fold research strategy to: (1) identify physical diseases that can be differentially diagnosed for psychosis; and (2) determine the paraclinical exams allowing us to exclude these pathologies.

RESULTS

We identified 85 articles describing the autoimmune, metabolic, neurologic, infectious, and genetic differential diagnoses of psychosis. Clinical presentations are described, and a complete list of laboratory and imaging features required to identify and confirm these diseases is provided.

CONCLUSION

This systematic review shows that most differential diagnoses of psychosis should be considered in the case of a FEP and could be identified by providing a systematic checkup with a laboratory test that includes ammonemia, antinuclear and anti-NMDA antibodies, and HIV testing; brain magnetic resonance imaging and lumbar puncture should be considered according to the clinical presentation. Genetic research could be of interest to patients presenting with physical or developmental symptoms associated with psychiatric manifestations.

[Acute hemorrhagic leukoencephalitis with a subacute onset]

Acute hemorrhagic leukoencephalitis (AHLE), also called Hurst's encephalitis, is a rare demyelinating disease of the central nervous system characterized by rapid progression and acute inflammation of the white matter of the brain and spinal cord. AHLE is currently considered as a rare, most severe variant of acute disseminated encephalomyelitis. Clinically AHLE is characterized by a fulminant course with a rapid development of encephalopathy and multifocal neurological symptoms. AHLE is associated with high mortality rate that requires immediate and aggressive treatment initiation. This article describes a case of AHLE with an atypical course, a subacute form, which is extremely rarely described in the literature, with the progressive symptoms' development over several months. Due to delayed treatment initiation, unfortunately, a fatal outcome has been observed. Subsequent histological examination of the autopsy material confirmed the presence of a subacute form of AHLE in the patient.

Brain anomalies in early psychosis: From secondary to primary psychosis

Brain anomalies are frequently found in early psychoses. Although they may remain undetected for many years, their interpretation is critical for differential diagnosis. In secondary psychoses, their identification may allow specific management. They may also shed light on various pathophysiological aspects of primary psychoses. Here we reviewed cases of secondary psychoses associated with brain anomalies, reported over a 20-year period in adolescents and young adults aged 13-30 years old. We considered age at first psychotic symptoms, relevant medical history, the nature of psychiatric symptoms, clinical red flags, the nature of the brain anomaly reported, and the underlying disease. We discuss the relevance of each brain area in light of normal brain function, recent case-control studies, and postulated pathophysiology. We show that anomalies in all regions, whether diffuse, multifocal, or highly localized, may lead to psychosis, without necessarily being associated with non-psychiatric symptoms. This underlines the interest of neuroimaging in the initial workup, and supports the hypothesis of psychosis as a global network dysfunction that involves many different regions.

Measles Resurgence and Drug Development

Measles caused an estimated minimum of one million fatalities annually before vaccination. Outstanding progress towards controlling the virus has been made since the measles vaccine was introduced, but reduction of measles case-fatalities has stalled at around 100,000 annually for the last decade and a 2019 resurgence in several geographical regions threatens some of these past accomplishments. Whereas measles eradication through vaccination is feasible, a potentially open-ended endgame of elimination may loom. Other than doubling-down on existing approaches, is it worthwhile to augment vaccination efforts with antiviral therapeutics to solve the conundrum? This question is hypothetical at present, since no drugs have yet been approved specifically for the treatment of measles, or infection by any other pathogen of the paramyxovirus family. This article will consider obstacles that have hampered anti-measles and anti-paramyxovirus drug development, discuss MeV-specific challenges of clinical testing, and define drug properties suitable to address some of these problems.

Neuropsychological and psychiatric outcomes in encephalitis: A multi-centre case-control study

Objectives

Our aim was to compare neuropsychological and psychiatric outcomes across three encephalitis aetiological groups: Herpes simplex virus (HSV), other infections or autoimmune causes (Other), and encephalitis of unknown cause (Unknown).

Methods

Patients recruited from NHS hospitals underwent neuropsychological and psychiatric assessment in the short-term (4 months post-discharge), medium-term (9–12 months after the first assessment), and long-term (>1-year). Healthy control subjects were recruited from the general population and completed the same assessments.

Results

Patients with HSV were most severely impaired on anterograde and retrograde memory tasks. In the short-term, they also showed executive, IQ, and naming deficits, which resolved in the long-term. Patients with Other or Unknown causes of encephalitis showed moderate memory impairments, but no significant impairment on executive tests. Memory impairment was associated with hippocampal/medial temporal damage on magnetic resonance imaging (MRI), and naming impairment with left temporal and left frontal abnormalities. Patients reported more subjective cognitive complaints than healthy controls, with tiredness a significant problem, and there were high rates of depression and anxiety in the HSV and the Other encephalitis groups. These subjective, self-reported complaints, depression, and anxiety persisted even after objectively measured neuropsychological performance had improved.

Conclusions

Neuropsychological and psychiatric outcomes after encephalitis vary according to aetiology. Memory and naming are severely affected in HSV, and less so in other forms. Neuropsychological functioning improves over time, particularly in those with more severe short-term impairments, but subjective cognitive complaints, depression, and anxiety persist, and should be addressed in rehabilitation programmes.

Medical Etiologies of Secondary Psychosis in Children and Adolescents

This is an updated review of child and adolescent somatic disorders associated with psychosis/psychotic symptoms, organized into neurologic, infectious, genetic, inborn errors of metabolism, autoimmune, rheumatologic, endocrine, nutritional, metabolic, and iatrogenic categories. When possible clinical manifestations or types of psychotic symptoms and proposed neuropathogenesis causing the neuropsychiatric symptoms are included. In some cases, the psychiatric symptoms may be the first presentation of the disease. The authors hope that this review will aid child and adolescent psychiatrists in considering alternative etiologies of youth presenting with psychosis and encourage appropriate physical examination, history, and further work-up when suspected.

Measles-related hospitalizations and associated complications in Jerusalem, 2018-2019

OBJECTIVES

The 2018 measles outbreak in Israel affected >2000 people in Jerusalem. The aim of the study was to describe clinical features and complications of hospitalized measles patients in Jerusalem, as related to age group and risk factors.

METHODS

All individuals hospitalized with measles in the three main hospitals in Jerusalem during March 2018 to February 2019 were included. Demographic, clinical and laboratory data were analysed.

RESULTS

Of 161 hospitalized individuals, 86 (53.4%) were <5 years old, 16 (10%) were ≥5 years but <20 years old, and 59 (36.6%) were ≥20 years old. Most, 114/135 (85%), were unvaccinated. Immunocompromised state was identified in 12/161 (7.5%) patients, 20/161 (12.4%) had other underlying co-morbidities, and four were pregnant. Hypoxaemia on admission was a common finding in all age groups. Hepatitis was more common among adults ≥20 years old (33/59, 59%). Measles-related complications were noted in 95/161 (59%) patients, and included pneumonia/pneumonitis (67/161, 41.6%), which was more common in young (<5 years) children, diarrhoea (18/161, 11.2%), otitis (18/161, 11.2%), and neurological complications (6/161, 3.7%)-the latter occurring more frequently in the 5- to 20-year age group. Two of the 12 immunocompromised patients died of measles-related complications. A high re-admission rate (19/161, 11.8%) within 3 months was documented among hospitalized measles patients.

CONCLUSION

The burden of hospitalization, as well as the high rate of short- and long-term complications observed in hospitalized patients, underscore the importance of maintaining a high measles vaccine coverage, with enhanced targeting of unvaccinated population pockets.

A clinical approach to new-onset psychosis associated with immune dysregulation: the concept of autoimmune psychosis

Growing data point to the overlap between psychosis and pathological processes associated with immunological dysregulation as well as inflammation. Notably, the recent discovery of antibodies against synaptic and neuronal cell membrane proteins such as anti-N-methyl-d-aspartate receptor provides more direct evidence of the etiological connection between autoimmunity and subsequent hazard of psychosis. Here, we advocate the use of term “autoimmune psychosis,” as this term suggests that autoimmune disorders can masquerade as drug-resistant primary psychosis, and this subtype of psychosis has anatomical and immunological footprints in the brain, despite the frequent absence of structural abnormalities on conventional brain MRI. Furthermore, this term might serve as a reminder not to overlook appropriate neurological workup such as neuroimaging and EEG testing, as well as CSF analysis, for cases with acute or subacute atypical onset of neuropsychiatric presentations including those dominated by acute psychotic symptoms. We propose etiologically and serologically oriented subclassification as well as multi-modal diagnostic approach to address some of the challenges inherent to early diagnosis of patients presenting with atypical and refractory new-onset psychotic symptoms of autoimmune origin. This is particularly relevant to the diagnosis of seronegative but probable autoimmune psychosis (SPAP) that might masquerade as antipsychotic drug-resistant primary psychotic disorder. This distinction is therapeutically important as autoimmune-related psychotic symptomatology can frequently respond well to timely treatment with proper immune modulatory therapies.

Long-term poor rapport, lack of spontaneity and passive social withdrawal related to acute post-infectious encephalitis: a case report

INTRODUCTION

Post-infectious encephalitis/encephalopathy is a neurological syndrome that sometimes develops following common viral or bacterial infections. The most common form is acute disseminated encephalomyelitis (ADEM). ADEM is a demyelinating disease of the central nervous system that typically presents as a monophasic disorder associated with multifocal neurologic symptoms and encephalitis. Anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis is another type of severe autoimmune disorder, characterized by seizures, movement disorders and psychiatric symptoms. In general, the prognosis and long-term outcomes of both ADEM and anti-NMDAR encephalitis are favorable. Most patients show complete, albeit slow recovery over a period of one to 2 years. There are few reports of patients with these disorders showing long-term residual psychiatric symptoms.

CASE PRESENTATION

We report the case of a 16-year-old Japanese male who suffered from acute post-infectious encephalitis. The patient followed an atypical recovery course, in that he showed poor rapport, lack of spontaneity and passive social withdrawal for more than 2 years after the initial symptoms. While treatment with small doses of antipsychotic drugs at the hospital had no effect on the symptoms, the patient recovered gradually over a prolonged period of five or so years.

CONCLUSIONS

This case report suggests that a type of acute post-infectious encephalitis with demyelinating features, possibly ADEM or anti-NMDAR encephalitis, or an overlap between the two, can cause a prodrome of behavioral changes and long-term residual psychiatric symptoms for many months, although it is eventually associated with a good prognosis.

Pediatric Urinary Retention in the Emergency Department: A Concerning Symptom with Etiology Outside the Bladder

BACKGROUND

Urinary retention in an otherwise healthy adolescent is a concerning symptom, in which etiology can range from an extracystic mass to central nervous system involvement (CNS). One possibility is acute disseminated encephalomyelitis (ADEM), a rare inflammatory autoimmune disease that affects the CNS via demyelination. The disease usually is preceded by an acute viral infection, and commonly presents with multifocal neurological deficits. The diagnosis for ADEM is made based on clinical presentation, correlating with findings characterized on magnetic resonance imaging (MRI) in the CNS.

CASE REPORT

Our case involves a 16-year-old boy who presented to the Emergency Department (ED) with urinary retention. The patient was an otherwise healthy adolescent who was experiencing intermittent fevers for 1 week, and was found to be monospot positive when seen by his pediatrician. When presenting to the ED, the patient's primary complaint was urinary retention, which he experienced acutely in the middle of the night. Due to the suspicious nature of the patient's symptoms and history of present illness, the patient received a thorough workup including magnetic resonance imaging (MRI) of the patient's brain and spinal cord, which demonstrated findings consistent with ADEM. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: There is very little literature describing a case of ADEM in the ED where the primary manifesting symptom was urinary retention. In addition, it is important that clinicians address acute urinary retention in an otherwise healthy adolescent as a red flag, with the need to rule out concerning etiology.

Synergizing vaccinations with therapeutics for measles eradication

INTRODUCTION

The measles virus is a major human pathogen responsible for approximately 150,000 deaths annually. The disease is vaccine preventable and eradication of the virus is considered feasible, in principle. However, a herd immunity exceeding 95% is required to prevent sporadic viral outbreaks in a population. Declining disease prevalence, combined with public anxiety over the vaccination's safety, has led to increased vaccine refusal, especially in Europe. This has led to the resurgence of measles in some areas.

AREAS COVERED

This article discusses whether synergizing effective measles therapeutics with the measles vaccination could contribute to finally eradicating measles. The authors identify key elements in a desirable drug profile and review current disease management strategies and the state of experimental inhibitor candidates. The authors also evaluate the risk associated with viral escape from inhibition, and consider the potential of measles therapeutics in the management of persistent central nervous system (CNS) viral infection. Finally, the authors contemplate the possible impact of therapeutics in controlling the threat imposed by closely related zoonotic pathogens of the same genus as measles.

EXPERT OPINION

Efficacious therapeutics used for post-exposure prophylaxis of high-risk social contacts of confirmed index cases may aid measles eradication by closing herd immunity gaps; this is due to vaccine refusal or failure in populations with overall good vaccination coverage. The envisioned primarily prophylactic application of measles therapeutics to a predominantly pediatric and/or adolescent population, dictates the drug profile. It also has to be safe and efficacious, orally available, shelf-stable at ambient temperature and amenable to cost-effective manufacturing.

Acute disseminated encephalomyelitis: the time until diagnosis and its subsequent course in children

Acute disseminated encephalomyelitis has an acute onset followed by improvement over several weeks. However, some cases require more time for a definitive diagnosis after protracted psychiatric or nonspecific symptoms. The authors investigated the time from onset to definitive diagnosis, subsequent course of treatment, and outcomes in 7 children with acute disseminated encephalomyelitis treated at the authors' hospital. The mean duration of illness before definitive diagnosis was 20.7 days (range: 2-50 days). Steroid pulse therapy was performed in all cases, and rapid improvements were observed; the mean duration from treatment initiation to hospital discharge was 8.6 days (range: 4-14 days). None of the cases showed neurological sequelae. Although this study investigated a small number of patients, its results suggest that time to diagnosis is often longer in children than in adults, and even in cases of delayed treatment, response to steroid pulse therapy is good and outcomes may not necessarily be affected.

Acute disseminated encephalomyelitis presenting as depressive episode

A 9-year-old girl presented to the Child Guidance Clinic with clinical features suggestive of depressive episode of 1 week duration. There was history of short febrile illness 3 weeks prior to the onset of the depressive symptoms. MRI scan of brain showed features of acute disseminated encephalomyelitis.

Lethal acute demyelinization with encephalo-myelitis as a complication of cured Cushing's disease

Cushing's disease is usually associated with higher mortality rate, especially from cardiovascular causes. Development or exacerbation of autoimmune or inflammatory diseases is known to occur in patients with hypercortisolism after cure. We report for the first time a 34-year old woman with a psychiatric background, who developed four months after the surgical cure of Cushing's disease an acute disseminated encephalomyelitis (ADEM) presenting initially as a psychiatric illness. We hypothesize that the recent correction of hypercortisolism triggered ADEM and that the atypical presentation, responsible for diagnosis delay, led to the death of this patient.

Psychiatric comorbidity in pediatric patients with demyelinating disorders

Little is known about psychiatric aspects of pediatric demyelinating conditions. A total of 23 youths (6-17 years) with demyelinating conditions underwent semistructured psychiatric interviews using the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version. Adolescents and parents completed the Child Symptom Inventory-4 and the Youth's Inventory-4. Fears and conceptions of their neurological problems were elicited. In all, 48% (n = 11) met criteria for current psychiatric diagnoses, including 27% (n = 3) with depressive disorders and 64% (n = 7) with anxiety disorders. Fears and conceptions of the illness were severe and diverse. Depressive and anxiety disorders are common in pediatric demyelinating disease. Clinicians should therefore screen for psychiatric comorbidity symptoms as part of the routine evaluation of such patients.

A case of acute disseminated encephalomyelitis in a 12-year-old boy

Acute disseminated encephalomyelitis is an uncommon inflammatory demyelinating disease of the central nervous system. It generally presents after a nonspecific viral infection. We describe a case of a male adolescent who presented to the emergency department with vomiting and lethargy. A review of the pathophysiology and clinical presentation for acute disseminated encephalomyelitis is presented here.

An autopsy case of acute multiple sclerosis (Marburg's type) during pregnancy

We report a case of a 9-month pregnant woman who presented acute psychiatric and neurological symptoms with extensive involvement of the white matter on MRI and no oligoclonal bands on CSF examination. Despite high doses of intravenous steroids, plasmapheresis and immunosuppressive drugs, a fatal outcome (coma) was noted 8 months later. Neuropathological examination confirmed the diagnosis of Marburg's type of multiple sclerosis showing sharp-edged lesions of demyelination, giant astrocytes, numerous macrophages and little perivascular inflammation. We discuss the definition and limits of the Marburg entity with reference to acute disseminated encephalomyelitis, impact of pregnancy, unusual MRI features, neuropathology and treatment.

Involvement of morbilliviruses in the pathogenesis of demyelinating disease

Two members of the morbillivirus genus of the family Paramyxoviridae, canine distemper virus (CDV) and measles virus (MV), are well-known for their ability to cause a chronic demyelinating disease of the CNS in their natural hosts, dogs and humans, respectively. Both viruses have been studied for their potential involvement in the neuropathogenesis of the human demyelinating disease multiple sclerosis (MS). Recently, three new members of the morbillivirus genus, phocine distemper virus (PDV), porpoise morbillivirus (PMV) and dolphin morbillivirus (DMV), have been discovered. These viruses have also been shown to induce multifocal demyelinating disease in infected animals. This review focuses on morbillivirus-induced neuropathologies with emphasis on aetiopathogenesis of CNS demyelination. The possible involvement of a morbillivirus in the pathogenesis of multiple sclerosis is discussed.

Neuropsychological and psychiatric profiles in acute encephalitis in adults

Acute encephalitis is an inflammation of brain tissue that can result from activity in the central nervous system (CNS) of a number of viruses. Although the neurological and psychiatric effects of encephalitis in the acute phase of the illness are well-known (Caroff, Mann, Gliatto, Sullivan, & Campbell, 2001), larger scale studies of the pattern of neuropsychological and psychiatric impairment following recovery from the acute inflammatory phase are less apparent. This paper reports the results of neuropsychological testing with a range of standardised cognitive measures in a case series of long-term post-acute participants. Psychiatric abnormality is examined using the SCL-90-R self-report scale of distress (Derogatis, 1983). We also examined the role of emerging insight in the aetiology of depression in this population. Two clusters of cognitive dysfunction were observed, one group of primarily herpes simplex cases showing a severe generalised deficit across a number of cognitive domains and a second cluster showing a variety of more isolated disorders of executive function. Abnormally high levels of distress were reported by participants, with depression, obsessive-compulsive symptoms, interpersonal sensitivity and phobic anxiety most significantly increased. Depression was found to be least severe in those with most accurate insight into their problems. Examining the correlations between cognitive and psychiatric test results demonstrates a relationship between depression and interpersonal anxiety and specific cognitive measures. Obsessive-compulsive behaviour and phobic anxiety, however, appear to exist independently of the assessed cognitive deficits.

Psychosis related to neurological conditions: pro and cons of the dis- / mis-connectivity models of schizophrenia

Schizophrenia is still a condition with obscure causes and psychopathology. This paper aims to discuss the “disconnectivity” hypothesis in relation to some neurological conditions which are known to alter brain connectivity, as well as mimicking some aspects of the disorder. After a short historical introduction to the concept, we will examine the evidence for connectivity problems in schizophrenia, separating the anatomical level from the functional level. Then, we will discuss three different issues concerning connectivity: i) local reduction in connectivity without neuronal loss (within the gray matter); ii) reduction in or alteration of long-range connectivity (within the white matter); and iii) abnormal targets for connections. For each of these aspects, we will look at the conditions able to reproduce anomalies capable of increasing susceptibility to schizophrenia. We conclude that psychosis is more likely to occur: i) when long-range connectivity is concerned; ii) when lesions result in lengthening and scattering of conduction times; and iii) when there are high dopamine levels, shedding light on or adding weight to the idea of an interaction between dopamine and connectivity.

Psychiatric manifestations of multiple sclerosis and acute disseminated encephalomyelitis

It is unusual for acute disseminated encephalomyelitis and multiple sclerosis to present as purely psychiatric disorders. We report five patients with such demyelinating diseases and symptoms of psychosis, depression or anxiety. The importance of excluding demyelination as the basis for these psychiatric disturbances is emphasized, especially in the presence of unexplained neurologic findings. The possible relationship between psychiatric symptoms and demyelinating disorders is explored.

Segmental myoclonus as the presenting symptom of an acute disseminated encephalomyelitis: a case report

Segmental myoclonus is described as the involuntary contractions of contiguous muscles innerved by the brain stem or by spinal cord. The underlying causes of segmental myoclonus in children are demyelinating diseases and intrinsic tumors. Here, we report a case who was presented with segmental myoclonus on his left arm and later diagnosed as atypical monosymptomatic presentation of acute disseminated encephalomyelitis (ADEM). The case represents the first in the literature in which ADEM is considered as the possible cause of segmental myoclonus. Our findings demonstrate that: (i) in focal movement disorders such as segmental myoclonus, a careful neuroradiological examination of the neuroanatomical region for the possible presence of organic lesions might be rewarding, (ii) ADEM might be one of the potentially reversible causes of myoclonus.

Viral diseases of the central nervous system

Viral diseases of the central nervous system encompass a wide range of different processes, mainly inflammation affecting the brain (encephalitis), the meninges (meningitis), or a combined meningoencephalitis. The spinal cord can be affected as well (myelitis). Another group of viral-related disorders, sometimes without a clear pathophysiological mechanism disclosed, include post-viral illnesses. All of these groups of diseases are discussed in this article, with an emphasis on their imaging presentation, using magnetic resonance imaging.

Morbilliviruses and human disease

Morbilliviruses are a group of viruses that belong to the family Paramyxoviridae. The most instantly recognizable member is measles virus (MV) and individuals acutely infected with the virus exhibit a wide range of clinical symptoms ranging from a characteristic mild self-limiting infection to death. Canine distemper virus (CDV) and rinderpest virus (RPV) cause a similar but distinctive pathology in dogs and cattle, respectively, and these, alongside experimental MV infection of primates, have been useful models for MV pathogenesis. Traditionally, viruses were identified because a distinctive disease was observed in man or animals; an infectious agent was subsequently isolated, cultured, and this could be used to recapitulate the disease in an experimentally infected host. Thus, satisfying Koch's postulates has been the norm. More recently, particularly due to the advent of exceedingly sensitive molecular biological assays, many researchers have looked for infectious agents in disease conditions for which a viral aetiology has not been previously established. For these cases, the modified Koch's postulates of Bradford Hill have been developed as criteria to link a virus to a specific disease. Only in a few cases have these conditions been fulfilled. Therefore, many viruses have over the years been definitely and tentatively linked to human diseases and in this respect the morbilliviruses are no different. In this review, human diseases associated with morbillivirus infection have been grouped into three broad categories: (1) those which are definitely caused by the infection; (2) those which may be exacerbated or facilitated by an infection; and (3) those which currently have limited, weak, unsubstantiated or no credible scientific evidence to support any link to a morbillivirus. Thus, an attempt has been made to clarify the published data and separate human diseases actually linked to morbilliviruses from those that are merely anecdotally associated.

Childhood autoimmune neurologic diseases of the central nervous system

An autoimmune mechanism for ADEM and MS can be supported by the similar patterns of pathologic changes seen in both diseases with the animal model EAE induced by inoculating animals with nervous tissue and the occurrence of ADEM in patients exposed to nervous tissue during vaccination. Whereas there are no universally agreed-upon criteria for the diagnosis of ADEM, a combination of prodromal illness or preceding vaccination, MRI signs of demyelination, and an acute presentation of neurologic symptoms are the triad most commonly looked for in making the diagnosis of ADEM. An ever-increasing number of infections and vaccinations (nonspecific URIs being most common) has been associated with ADEM. Fever and encephalopathy are seen frequently at presentation. Seizures also are common, as are cranial nerve abnormalities and motor symptoms. A mild pleocytosis or protein elevation is found in the majority of patients with ADEM. Intrathecal IgG synthesis and oligoclonal bands are relatively infrequent but should not be considered inconsistent with the diagnosis of ADEM. White matter changes on T2 in a bilateral although asymmetric distribution with relative sparing of the periventricular region with or without deep gray matter involvement is consistent and to some a requirement for the diagnosis. Low-dose steroids have no beneficial effect in the treatment of ADEM and may be contraindicated. High-dose steroids may have a beneficial effect, particularly in more prolonged illnesses, although the evidence is primarily anecdotal. If steroids are used to improve morbidity, 30 mg/kg/d of methylprednisolone for three to five days is the dose with a six-week taper to reduce the risk of recurrence. The prodromal infection may be a major factor in the ultimate mortality and morbidity of the disease. The current mortality of ADEM is quite low. Whether or not this is an effect of different triggering agents or changes in medical care cannot be determined. In larger series of patients with ADEM, 10% to 20% of children experience some sort of recurrence with the majority occurring in the initial one to two months after the first event. This is sometimes associated with steroid withdrawal. A second group of children have a late second recurrence that clinically may not be MS but a recurrence of ADEM, although longer follow-up may change that assessment. Two months should be allowed before a second relapse is considered a manifestation of MS, whereas a second attack also may occur years after an initial attack of ADEM and still be consistent with ADEM recurrence. MS does occur during childhood, with the youngest children at the least risk, and risk increasing with age. The criteria of Poser et al can be used to diagnose MS in childhood [40]. The presentation of MS in childhood is most often sensory, motor, and brainstem signs and symptoms. A relapsing-remitting course is most common with a first relapse occurring in the year after presentation. MRI findings in MS typically show periventricular changes. Oligoclonal bands and CSF IgG synthesis are found in the majority. Treatments of childhood MS have not been studied adequately, but, when treatments studied in adults are used in children, they are well tolerated. Efficacy has not been shown. The long-term outcome of MS in childhood can be either severe or benign with no clear consensus that childhood MS is either a less or more severe disease than the adult form. ATM and ON treatments and outcomes are particularly difficult to evaluate because of the heterogeneity of populations included in case series and the small numbers reported. Steroids are used with anecdotal reports of their superiority to nontreatment. Outcome in ATM often can be poor, whereas in ON it rarely is. A multinational collaborative effort to study and collect the large numbers necessary to address the important questions in these childhood autoimmune disorders would be of great benefit and the only way likely to demonstrate good evidenced-based medicine practiced in this field.

Multiple complete ring-shaped enhanced MRI lesions in acute disseminated encephalomyelitis

Acute disseminated encephalomyelitis (ADEM) lesions may or may not enhance with contrast material on contrast T1-weighted magnetic resonance images (T1WI). Enhancing ADEM lesions may show varying patterns of contrast enhancement, which include nodular, diffuse nodular, amorphous, gyral, spotty and incomplete ring-like. Multiple, complete ring-shaped enhanced lesions on contrast T1WI is a rare finding in ADEM. We report such a magnetic resonance imaging (MRI) finding in a 36-year-old female patient with this disease.

Postinfectious encephalomyelitis

Postinfectious forms of encephalomyelitis, also termed acute disseminated encephalomyelitis (ADEM), form one of several categories of inflammatory demyelinating disorders of the central nervous system (CNS). Recent large, retrospective case series have refined our understanding of the clinical, laboratory, and neuroimaging characteristics of ADEM. The differences between childhood and adult ADEM, risks of development of multiple sclerosis, and the contributions of recent studies to refining the nosology of CNS demyelinating syndromes are discussed.

Acute disseminated encephalomyelitis: recognition in the hands of general paediatricians

Acute disseminated encephalomyelitis will often present to the general paediatrician as an acute polysymptomatic encephalopathy, and initially the diagnosis may not be clear. A brain MRI scan is essential in establishing the diagnosis and so enabling appropriate advice and treatment to be given. Multicentre clinical audit of outcome and controlled therapeutic trials are needed to secure an evidence base for current practice.

Acute flaccid paralysis in Australian children

OBJECTIVES

To describe the epidemiology and causes of acute flaccid paralysis (AFP) in Australian children, and the clinical features of the two most common causes of AFP, Guillain-Barré syndrome and transverse myelitis.

METHODS

Monthly active surveillance for AFP was carried out through the Australian Paediatric Surveillance Unit, with AFP defined as 'acute onset of flaccid paralysis in one or more limbs or of bulbar paralysis in any child less than 15 years of age'.

RESULTS

Between March 1995 and December 1999, 143 cases of AFP were reported (approximately 0.8 per 100000 children < 15 years of age per annum). The age range was 2 months-14 years and 59% were boys. Out of these children, 137 (96%) were hospitalized and 47 required intensive care. No case of wild or vaccine-associated poliomyelitis was identified. The most common causes of AFP were Guillain-Barré syndrome in 67 (47%) and transverse myelitis in 27 (19%). Other diagnoses included acute disseminated encephalomyelitis, trauma, tick-bite paralysis and infantile botulism.

CONCLUSION

The participation of paediatricians in AFP surveillance contributed to the accreditation of Australia (along with the other 36 countries of the western Pacific region) as 'polio free' by the World Health Organization in October 2000. The surveillance also provided data on the frequency of AFP and identified Guillain-Barré syndrome and transverse myelitis as the most common diagnoses. In this large national series, many other conditions that may present as non-polio AFP were identified.

Detection of infectious agents in brain of patients with acute hemorrhagic leukoencephalitis

Acute hemorrhagic leukoencephalitis (AHL) is a rare and usually fatal disorder characterized clinically by an acute onset of neurologic abnormalities. It may occur in association with a viral illness or vaccination. Radiology and brain biopsy are essential for the diagnosis. The etiology of AHL is unclear. We postulated that viral/bacterial infection might be responsible, directly or through an immune-mediated mechanism, for this acute inflammatory myelinopathy. Fifteen cases of AHL were studied. Infectious agents, including varicella zoster virus (VZV), herpes simplex virus (HSV), human herpes virus-6 (HHV-6), cytomegalovirus, Epstein-Barr virus, and Mycoplasma, were investigated in brain specimens using the polymerase chain reaction (PCR), reverse transcriptase (RT)-PCR, and immunohistochemistry. Using PCR, HSV DNA was found in four cases, VZV DNA in two, and HHV-6 DNA in one. Among the control cases, two were HSV DNA positive. Further investigation to detect HSV RNA and antigens in HSV DNA-positive cases revealed that two cases with AHL were both HSV RNA and antigen positive. AHL is a hyperacute disease, which is considered the most acute form of acute disseminated encephalomyelitis (ADEM). Our findings suggests that a viral infection may be implicated in its pathogenesis, most likely through an indirect mechanism; however, as only a few cases of this rare disease were examined, statistical significance was not achieved. As a number of patients with disorders of the ADEM group may progress to develop multiple sclerosis (MS), we argue that an organism that has produced the former may remain in the brain tissue and be subsequently involved in the production of a self-sustained disorder such as MS.

Acute disseminated encephalomyelitis following nephropathia epidemica

Acute disseminated encephalomyelitis (ADEM) is an acute monophasic inflammatory and demyelinating disease of the central nervous system (CNS) occurring days to weeks after a virus infection or vaccination. Nephropathia epidemica (NE) is a haemorrhagic fever with renal syndrome caused by Puumala virus, with endemic regions in Europe, especially Scandinavia and Western Russia. We describe a case of severe nephropathia epidemica requiring dialysis, followed by severe CNS symptoms caused by ADEM. To our best knowledge this is the first case in the literature in which NE caused ADEM.

Acute disseminated encephalomyelitis associated with parainfluenza virus infection of childhood

Acute disseminated encephalomyelitis associated with the parainfluenza virus has rarely been reported in childhood. A 2.5-year-old girl with acute disseminated encephalomyelitis, who developed bilateral symmetrical lesions in the basal ganglion, thalamus, corpus callosum, cerebral subcortical white matter, and cerebellar medulla on brain magnetic resonance imaging is described. Serological confirmation of parainfluenza virus infection was made 2 weeks following the onset of neurological symptoms. Four months later, the patient had a full recovery. At present, 3 years later, no relapse has been reported and she is leading a normal life. Our case is of interest because of its rarity, the striking brain magnetic resonance imaging, and the good neurological outcome.

Enteroviral encephalitis leading to a locked-in state

Millions of children are infected by enteroviruses each year, usually exhibiting only mild symptoms. Although enteroviruses are a common cause of community-acquired aseptic meningitis, enteroviral meningitis usually has a benign course. We describe a 14-year-old patient with enteroviral meningoencephalitis diagnosed by polymerase chain reaction. Her level of consciousness declined rapidly after hospital admission and resulted in a locked-in state. Although she experienced slow neurologic improvement, residual neurologic deficits remain. Although there is a general awareness of the characteristics of enteroviralencephalitis, this case report is significant in presenting a case of unusual severity and sequelae. To our knowledge, this is the first published report of an enterovirus encephalitis leading to a locked-in-state.

Acute disseminated encephalomyelitis in autoimmune hemolytic anemia

A 16-year-old female with chronic autoimmune hemolytic anemia is presented. She was diagnosed with acute disseminated encephalomyelitis by clinical findings and magnetic resonance imaging (MRI), and the condition occurred after a systemic infection with Cryptococcus neoformans. Intravenous immunoglobulin therapy remarkably improved the patient's neurologic deficit and resolved abnormalities evidenced on MRI. To our knowledge, this report is the first of a pediatric patient with autoimmune hemolytic anemia complicated by acute disseminated encephalomyelitis that developed after an apparently successful treatment of cryptococcal meningitis.