Computed tomography in acute disseminated encephalomyelitis

Neurosurgical intervention in an unusual case of extensive acute disseminated encephalomyelitis - A case report and literature review

Background

The clinical presentations of demyelinating diseases are variable and can range from mild symptoms to fulminant presentations. Acute disseminated encephalomyelitis is one of those diseases which usually follow an infection or vaccination.

Case Description

We report a case of extensive acute demyelinating encephalomyelitis (ADEM) with massive brain swelling. A 45-year-old female presented to the emergency room with status epilepticus. Patient has no history of any associated medical problems. Glasgow coma scale (GCS) was 15/15. CT brain was normal. Lumbar puncture was done and cerebrospinal fluid showed pleocytosis and increased protein content. About 2 days after admission, the conscious level rapidly deteriorated and GCS was 3/15, with the right pupil fully dilated and unreactive to light. Computed tomography and magnetic resonance imaging brain were done. We performed an urgent decompressive craniectomy as a life-saving procedure. Histopathological examination was suggestive of ADEM.

Conclusion

Few cases of ADEM with brain swelling were reported, but there is no solid consensus about the appropriate management of these cases. Decompressive hemicraniectomy is a possible choice, but further research is needed to evaluate the proper timing, and indication of surgery.

Acute Confusion in a Middle-Aged Woman

This is a report of a previously healthy 47-year-old lady who presented to the Accident & Emergency Department (AED) with acute confusion. She was subsequently diagnosed to be suffering from acute disseminated encephalomyelitis (ADEM). We report this rare case to alert emergency physicians to consider acute disseminated encephalomyelitis when presented with a patient with acute confusion. The diagnosis, investigation, management will be discussed.

A prospective study of magnetic resonance imaging patterns of central nervous system infections in pediatric age group and young adults and their clinico-biochemical correlation

Background:

Infections of the central nervous system (CNS) are common and routinely encountered. Our aim was to evaluate the neuroimaging features of the various infections of the CNS so as to differentiate them from tumoral, vascular, and other entities that warrant a different line of therapy.

Aims:

Our aim was to analyze the biochemical and magnetic resonance imaging (MRI) features in CNS infections.

Settings and Design:

This was a longitudinal, prospective study over a period of 1½ years.

Subjects and Methods:

We studied cerebrospinal fluid (CSF) findings and MRI patterns in 27 patients of 0–20 years age group with clinical features of CNS infections. MRI was performed on MAGNETOM Avanto 18 Channel 1.5 Tesla MR machine by Siemens India Ltd. The MRI protocol consisted of diffusion-weighted and apparent diffusion coefficient imaging, turbo spin echo T2-weighted, spin echo T1-weighted, fluid-attenuated inversion recovery (FLAIR), and gradient-echo in axial, FLAIR in coronal, and T2-weighted in sagittal plane. Contrast-enhanced T1-weighted sequence and MR spectroscopy were done whenever indicated.

Results and Conclusions:

We found that most of the children belong to 1–10 years age group. Fungal infections were uncommon, mean CSF adenosine deaminase values specific for tuberculosis and mean CSF glucose-lowered in pyogenic. Hemorrhagic involvement of thalamus with/without basal ganglia and brainstem involvement may indicate Japanese encephalitis or dengue encephalitis. Diffusion restriction or hemorrhage in not expected in the brainstem afflicted lesions of rabies. Congenital cytomegalovirus can cause cortical malformations. T1 hyperintensities with diffusion restriction may represent viral encephalitis. Lesions of acute disseminated encephalomyelitis (ADEM) may mimic viral encephalitis. Leptomeningeal enhancement is predominant in pyogenic meningitis. Basilar meningitis in the presence of tuberculomas is highly sensitive and specific for tuberculosis.

Encefalomielite acuta disseminata

L’encefalomielite acuta disseminata (EMAD) è una malattia infiammatoria autoimmune che coinvolge il cervello e il midollo spinale. Descritta soprattutto nel bambino, generalmente fa seguito a un episodio infettivo o a una vaccinazione, ma può essere idiopatica. La sua presentazione clinica comprende un’encefalopatia acuta associata a segni e a sintomi neurologici multifocali. La sua diagnosi si basa sulla clinica e sulla risonanza magnetica, che rivela lesioni multifocali della sostanza bianca in ipersegnale T2 mal delimitate, della stessa età, che prendono il gadolinio e possono anche riguardare il talamo e i nuclei della base. Il liquor può mostrare un’iperlinfocitosi con iperproteinorrachia e, a volte, la presenza di bande oligoclonali transitorie. La sua prognosi è piuttosto favorevole, passato l’episodio monofasico, con un trattamento specifico. È quindi fondamentale escludere fino dall’inizio le sue molte diagnosi differenziali. Il trattamento dell’EMAD, di prima scelta, consiste in boli di corticosteroidi endovenosi a forti dosi. In caso di insuccesso bisogna ricorrere agli scambi plasmatici o alle immunoglobuline endovenose. Anche se, di solito, è monofasica, possono verificarsi altri episodi che fanno allora pensare a un’EMAD multifasica. Tuttavia, in alcuni casi queste nuove poussées sono una modalità di esordio di un’autentica sclerosi multipla.

Acquired demyelinating disorders of childhood in the Western Cape, South Africa

In a retrospective review of patients with acquired demyelinating disorders of the central nervous system, 19 children (0.6%) were identified from the Paediatric Neurology database of 3159 patients; 7 had acute disseminated encephalomyelitis, 1 had Schilder's disease, 5 had multiple sclerosis, and 6 had acute transverse myelitis. The median age of presentation was 83 months, with increased incidence during the summer and winter months. The commonest presentation was hemiparesis. The commonest regions of magnetic resonance imaging (MRI) abnormalities were the deep white matter (68%) and cerebellum (48%).The patients with multiple sclerosis had more monosymptomatic presentations (P < .02), raised cerebrospinal fluid protein (P = .022), and contrast enhancement of lesions (P = .05) compared with the acute disseminated encephalomyelitis group. Neuroepidemiological published surveillances of African children provide no data about these disorders. The prevalence of acquired demyelinating disorders in resource-poor settings is under-estimated because of the large burden of infections and limited access to neuroimaging.

Acute disseminated encephalomyelitis after leptospirosis

We report a case of acute disseminated encephalomyelitis after infection by the spirochete Leptospira interrogans and review the few cases of acute disseminated encephalomyelitis and central nervous system disorders described in literature. The high prevalence of leptospirosis in developing countries and the possibility of acute disseminated encephalomyelitis, per se, highlights the importance of complete investigation for diagnosis and early treatment, leading to a better prognosis with reduction of morbidity and mortality rates.

Acute disseminated encephalomyelitis in North Indian children: clinical profile and follow-up

Acute disseminated encephalomyelitis in children is not uncommon in developing countries, yet there is little systematic documentation of its clinical profile and follow-up. We studied the clinical and neuroradiologic features of acute disseminated encephalomyelitis in 52 consecutive children. Clinical details, magnetic resonance imaging (MRI) findings, and the results of other investigations were recorded, and children were followed up from 6 to 48 months. A repeat MRI was done after 3 to 4 months, and in those with persistent lesions, another MRI was done after 6 to 7 months of discharge. The mean age at presentation was 6.14 +/- 3.17 years, 73.1% were male, and 17 children had a history of antecedent infectious illness or vaccination. Most children had a meningoencephalitic presentation, with sudden-onset motor weakness in 76.9% and seizures in 36.5%. Altered sensorium and pyramidal signs were seen in 55.8% and 80.7% of children, respectively. On MRI, scattered T(2)-weighted hyperintense lesions were seen, mainly in the subcortical white matter, especially in the parietal (53.8%) and frontal (30.17%) regions. Thalamic, basal ganglia, and callosal lesions were seen in 30.76%, 17.3%, and 13.46% of cases, respectively. Variable contrast enhancement was seen in 48% of those who had contrast MRIs. The response to methylprednisolone was good, with dramatic recovery in 26.9% and marked improvement in 51.9% at discharge. On follow-up, of 44 children, residual smaller MRI lesions were seen in 30. The MRI was repeated at 6 months in children with residual lesions, and it was found that the lesions either disappeared or were significantly reduced after 6 months in 75% of cases. Four children had relapse of acute disseminated encephalomyelitis with new lesions on MRI. All of them responded to methylprednisolone. None of the clinical or neuroradiologic factors at presentation had any significant correlation with relapse. Six months after discharge, no deficits could be found in 61.3% of cases; 15.9% and 4.5% had motor and cognitive deficits, and 9% had multiple deficits. The presentation of pediatric acute disseminated encephalomyelitis in developing countries is similar to that in developed countries. In spite of an aggressive presentation, most children respond well to corticosteroids. MRI lesions disappear or are significantly reduced at 6 months in the majority of cases.

Post-infectious encephalomyelitis

The term post-infectious encephalomyelitis (PIEM) is frequently used interchangeably with acute disseminated encephalomyelitis (ADEM), although technically PIEM occurs after a known infection whereas with ADEM there is no antecedent infection. PIEM represents one of the primary demyelinating disorders of the central nervous system, along with multiple sclerosis and Devic's disease. There is no specific diagnostic test for any of these conditions and at onset it may be difficult to differentiate between ADEM and the first attack of multiple sclerosis. However, there are clinical and magnetic resonance imaging features that allow differentiation between PIEM/ADEM and a relapsing disease such as multiple sclerosis. Some patients improve spontaneously; most improve with methylprednisolone. If that fails, plasma exchange or intravenous immunoglobulin may be effective.

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.

Solitary hemispheric demyelination in acute disseminated encephalomyelitis: clinicoradiological correlation

We retrospectively studied 13 patients with solitary hemispheric demyelination in acute disseminated encephalo--myelitis (solitary-ADEM) to look for specific MRI features. Thirteen patients were subjected to routine MRI with varying initial clinical diagnosis, including demyelination, neoplasm, encephalitis and infarct. The provisional MRI diagnosis was based on lesion morphology, size, location, mass effect, effect on adjacent sulci, cisterns and gyral shape. On long repetition time (TR)/long echo time (TE) spin echo sequences, the lesions were heterogeneously hyperintense, and on short TR/short TE spin echo sequences, heterogeneously hypointense. Later, the provisional MRI diagnosis was corroborated with clinical parameters such as multimode-evoked potentials, electro--physiological studies and analysis of cerebrospinal fluid (CSF) in order to establish a definitive diagnosis. The diagnosis was established in all except one patient with tumour-like clinical and MRI features. The combination of MRI features and clinical parameters can establish a definitive diagnosis in the majority of cases, and this avoids a biopsy.

Acute disseminated encephalomyelitis

Acute disseminated encephalomyelitis (ADEM) is an acute demyelinating disorder of the central nervous system, and is characterised by multifocal white matter involvement. Diffuse neurological signs along with multifocal lesions in brain and spinal cord characterise the disease. Possibly, a T cell mediated autoimmune response to myelin basic protein, triggered by an infection or vaccination, underlies its pathogenesis. ADEM is a monophasic illness with favourable long term prognosis. The differentiation of ADEM from a first attack of multiple sclerosis has prognostic and therapeutic implications; this distinction is often difficult. Most patients with ADEM improve with methylprednisolone. If that fails immunoglobulins, plasmapheresis, or cytotoxic drugs can be given. Recent literature suggests that a significant proportion of patients with ADEM will later develop multiple sclerosis; however, follow up experience from developing countries does not support this view.

Idiopathic Parkinson's disease(s) may follow subclinical episodes of perivenous demyelination

Three case studies of postvaccinal parkinsonism (PVP) demonstrated signs and symptoms identical to conventional diagnostic standards of idiopathic Parkinson's disease (PD). PVP is a sub-type of acute disseminated encephalomyelitis (ADE) that also includes postinfectious parkinsonism (PIP) and postinfectious encephalomyelitis (PIE). All ADE has a unitary pathology consisting of monophasic perivenous inflammation followed by demyelination compared with PD in which Lewy bodies are present in only 75% of studies. We hypothesize that: (1) The seminal event in PD is latent viral invasion emanating from cranial and dorsal root ganglia. (2) Viruses intermittently invade and damage neuropigmented cells secondary to perivenous demyelination. This may explain the numerous clinical and pathological manifestations of PD. Evidence is presented that this pathoetiology probably accumulates subclinically over a long timespan prior to Levy body formation and presentation of clinical signs. This hypothesis has key features similar to one previously published that will be summarized concerning multiple sclerosis.

ADEM: literature review and case report of acute psychosis presentation

Acute disseminated encephalomyelitis is a monophasic, immune-mediated disorder that produces multifocal demyelinating lesions within the central nervous system. It is characterized clinically by the acute onset of neurologic abnormalities, including varying degrees of mental state changes ranging from drowsiness to coma. It is unusual for the illness to present as an isolated acute psychosis. The case of a 14-year-old female with biopsy-confirmed acute disseminated encephalomyelitis, who was initially diagnosed with an acute psychiatric disorder, is presented, and published reports on this unusual manifestation are reviewed. A Medline database search was performed from 1965 to 1999, using the terms acute disseminated encephalomyelitis, postvaccinal encephalomyelitis, postinfectious encephalomyelitis, and measles encephalomyelitis, combined with the terms psychosis, psychiatric disorder, and behavioral disorder. Selected cross-referenced reports were also reviewed. Nine patients were identified who presented with acute psychosis. We conclude that, although rare, acute disseminated encephalomyelitis can present as an acute psychosis. This immune-mediated condition should be included in the differential diagnosis of neurologic disorders presenting as a psychiatric illness.

[Magnetic resonance imaging and clinical features in adults with monophasic demyelinating disease. Acute disseminated encephalomyelitis or a variant of multiple sclerosis?]

Acute disseminated encephalomyelitis (ADEM) is a widespread monophasic inflammatory disease affecting the central nervous system, that usually follows an infection or vaccination. In this study, we present an analysis of magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) and clinical aspects in four patients with clinical diagnosis of ADEM. The presence of MRI demyelinating lesions was crucial, but not in itself sufficient for definitive diagnosis. Clinical and MRI follow up, in order to exclude new lesions and to reevaluate the former ones, as well as CSF, were important for the differential diagnosis with other demyelinating diseases, particularly multiple sclerosis. In addition, we have shown that early treatment with methylprednisolone after the initial symptoms was effective for improving clinical manifestations as well as for reducing MRI lesions.

Long term MRI follow-up of patients with post infectious encephalomyelitis: evidence for a monophasic disease

Post infectious encephalomyelitis and multiple sclerosis are both inflammatory demyelinating disorders of the central nervous system. Whereas multiple sclerosis is a multi phasic disease with recurrent episodes disseminated in time and place, post infectious encephalomyelitis is usually considered to be a monophasic illness. This study used serial brain MRI to clarify whether the latter hypothesis holds for the long term. Post infectious encephalomyelitis was defined as the development of a central nervous system white matter disorder occurring in close temporal relationship with a viral, bacterial or other infection. There were eleven patients, mean age at presentation 21 years (4-48), and mean period of follow-up of 8 years (3.5-11). T2-weighted brain MRI was abnormal in all 11 cases during the acute stages of the illness. On follow-up 6 patients had made a complete clinical recovery, 4 patients had mild residual deficits and one severe neurological deficits necessitating ventilatory support. No patient experienced an exacerbation during the follow-up period. MRI revealed complete resolution of abnormalities in 3 and partial resolution in 7; new white matter lesions were seen in only one patient. This long term follow-up study suggests that there is a definable group with post infectious encephalomyelitis who exhibit a monophasic clinical and MRI pattern in the long term.

Pathogenesis, diagnosis, and treatment of acute disseminated encephalomyelitis

Acute disseminated encephalomyelitis is considered a monophasic, inflammatory demyelinating disorder of the central nervous system. A temporal relationship usually exists between the onset of neurologic symptoms and an infection or a vaccination. A viral exanthem facilitates the diagnosis. Some heterogeneity exists with regard to etiology and clinical course of this disease. Immunosuppression is considered the treatment of choice.

Acute hemorrhagic leukoencephalitis: recovery and reversal of magnetic resonance imaging findings in a child

A case of acute hemorrhagic leukoencephalitis (AHLE) in a 6-year-old girl is reported. The presentation was typical for acute hemorrhagic leukoencephalitis, with acute onset of a rapidly progressive neurologic disorder with asymmetric involvement of brain, with polymorphonuclear predominant peripheral leukocytosis and cerebrospinal fluid pleocytosis. Cerebrospinal fluid findings not previously reported included elevation of IgG and the presence of myelin basic protein. Additional previously unreported findings were striking abnormalities on magnetic resonance imaging (MRI) of the brain, in contrast to normal findings on computed tomography (CT). The child was treated with high dose intravenous steroids and made a full recovery, with a parallel disappearance of all of her cerebrospinal fluid abnormalities and almost all of her abnormalities on MRI. Detailed examination of cerebrospinal fluid and MRI of brain should facilitate early diagnosis in other cases of suspected acute hemorrhagic leukoencephalitis and high-dose steroid therapy may lead to improved clinical outcomes.

Subacute sclerosing panencephalitis presenting as acute disseminated encephalomyelitis: a case report

Subacute sclerosing panencephalitis is characterized by the insidious onset of diffuse cerebral dysfunction associated later with myoclonus and typical electroencephalographic changes. The disease progresses relentlessly to coma and death within 2 years. We report a case of acute onset and rapid course associated with atypical CSF, EEG and MRI features simulating acute disseminated encephalomyelitis. Brief review of relevant literature is presented.

Magnetisation transfer ratios and transverse magnetisation decay curves in optic neuritis: correlation with clinical findings and electrophysiology

Conventional MRI sequences do not permit the distinction between the different pathological characteristics (oedema, demyelination, gliosis, axonal loss) of the multiple sclerosis plaque. Magnetisation transfer imaging and transverse magnetisation decay curve (tMDC) analysis may be more specific. These techniques have been applied to the optic nerves in 20 patients with optic neuritis and the results correlated with clinical and visual evoked potential (VEP) findings. tMDC analysis failed to identify separate intracellular and extracellular water compartments within the optic nerve but gave a measure of transverse relaxation time (T2) without the confounding effects of CSF in the nerve sheath. Both T2 and magnetisation transfer ratio (MTR) were abnormal after an episode of optic neuritis. T2 did not correlate with visual function or with VEP latency or amplitude. There was a significant correlation between MTR reduction and prolongation of VEP latency: this increased latency may reflect an effect of myelin loss on MTR. Longer lesions were associated with worse visual outcome, implying that the overall extent of pathological involvement is likely to influence the degree of functional deficit.

Acute disseminated encephalomyelitis (ADEM) or ADEM-like inflammatory changes in a heart-lung transplant recipient: a case report

Acute disseminated encephalomyelitis (ADEM) is a white matter inflammatory disease which usually follows a viral infection or pharmaceutical intervention. We describe a case of presumed ADEM in a heart/lung transplant patient, the etiology of which cannot be elucidated. The fascinating aspect is the mode of clinical presentation and the rapid resolution of radiologic abnormalities. Histologic examination of the brain is provided in an attempt to elucidate the radiographic abnormalities.

MRI in acute disseminated encephalomyelitis

A retrospective analysis of CT and MRI studies in 12 patients with a clinical diagnosis of acute disseminated encephalomyelitis (ADEM) was performed. MRI was the definitive modality for the assessment of the lesions of ADEM: all patients had abnormalities consistent with the clinical diagnosis. Ten had abnormalities in the brain, three spinal cord lesions, and three showed evidence of optic neuritis. CT was normal in 6 of the 7 patients in which it was performed.

Acute hemiplegia syndrome in childhood

Three types of clinical features at the onset are well known to be characteristic of acute hemiplegia syndrome (AHS). Type 1 comprises status epilepticus of hemiconvulsions with fever. Representative diseases of this type are the infectious diseases of the central nervous system, acute encephalopathy and cerebral vascular diseases. Type 2 comprises status epilepticus of hemiconvulsions without fever. Cerebral vascular diseases and epilepsy are the major ones of this type. Type 3 comprises hemiplegia or hemiparesis of sudden onset without fever or convulsions. Most patients with this type had cerebral vascular diseases, about half of which were moyamoya disease in Japan. Recent progress in neuroimaging studies has allowed considerable elucidation of the etiology of AHS. Gadolinium-enhanced MRI showed minimal lesions such as capsular infarction more clearly than plain MRI. Acetazolamide test 99mTc-HMPAO SPECT imaging is one of the useful assisted diagnostic techniques for moyamoya disease, because it reveals the reserve capacity of the collaterals. [123I]IMP SPECT is useful for the diagnosis and follow-up of acute disseminated encephalomyelitis (ADEM), as the images of the lesions coincide well with the MRI ones. 99mTc-HMPAO SPECT in a case with alternating hemiplegia revealed normoperfusion in the ictal periods. Four cases of AHS are reported here.

Acute disseminated encephalomyelitis presenting as a solitary brainstem mass

A 36 year old woman presented with a subacute brainstem syndrome. MRI showed a solitary, gadolinium enhancing brainstem mass, which on biopsy showed perivenous inflammation and demyelination compatible with acute disseminated encephalomyelitis.

Acute disseminated encephalomyelitis probably related to a Mycoplasma pneumoniae infection

A 36-year-old woman was suffering from acute disseminated encephalomyelitis, which had been preceded by a febrile illness. Brain CT showed diffuse white matter hypo-attenuation. Electroencephalography initially revealed altered non-REM sleep followed by diffuse slowing. Brain stem auditory evoked potentials showed interwave delay, while pattern visual evoked potentials were normal. The patient made a full recovery and the CT scan and EEG normalized. Serological evidence of Mycoplasma pneumoniae was present.

Hepatitis A post-viral encephalitis

We report a seven-year-old girl who developed a hepatitis A viral infection and encephalitis. The patient developed fever, abdominal pains and jaundice. Five days later she became delirious, combative, and did not respond to verbal commands. Laboratory studies showed elevated liver enzymes and elevated serum immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies to hepatitis A virus. Cerebrospinal fluid contained IgG antibodies to hepatitis A virus but not IgM antibodies. Polymerase chain reaction, which amplifies a portion of the hepatitis A virus genome, did not demonstrate viral nucleic acid in cerebrospinal fluid. These studies suggest that the patient may have suffered from a post-viral hepatitis A encephalitis from which she fully recovered.

Acute severe combined demyelination

We present a second case in which Guillain-Barré syndrome (GBS) and acute disseminated encephalomyelitis (ADEM) appeared simultaneously, both in acute and fulminant form. The patient, a 10-year-old girl, presented with acute onset of coma and flaccid, are-flexic quadriparesis. The elevated CSF protein levels and delayed F waves fulfilled the criteria of GBS and an MRI study revealed extensive multifocal demyelination compatible with a diagnosis of ADEM. Prompt clinical response followed by complete recovery was achieved by treatment with corticosteroids. It is suggested that acute severe combined demyelination might constitute a separate entity in which the demyelinating process, involving simultaneously the central and the peripheral nervous systems, indicates immune response against a component of the myelin of one system carrying cross-antigenicity with the other.

Acute disseminated encephalomyelitis after Japanese B encephalitis vaccination

A 6-year-old girl (Patient 1) and a 5-year-old boy (Patient 2) with acute disseminated encephalomyelitis after Japanese B encephalitis vaccination are reported. Drowsiness, paresthesias, and gait disturbance were observed at 14 days (Patient 1) and 17 days (Patient 2) after the vaccination; however, transient impairment of visual acuity was only found in Patient 1. Laboratory examinations revealed slow theta waves on electroencephalography and elevated myelin basic protein in the cerebrospinal fluid in both patients. The most striking feature on magnetic resonance imaging was the combination of white matter lesions and abnormal intensity signals of the thalamus. The administration of oral prednisolone (2 mg/kg/day) markedly improved the clinical findings and abnormal magnetic resonance imaging findings. A similar magnetic resonance imaging finding of abnormal intensity of the thalamus with deep white matter lesions has been reported in patients with Japanese B encephalitis; therefore, thalamic lesions may be related to the naturally occurring encephalitis.

Role of plasmapheresis in acute disseminated (postinfectious) encephalomyelitis

Acute disseminated encephalomyelitis (ADEM) is a demyelinating central nervous system disease that is associated with high morbidity and mortality. Although the recognition of ADEM may be facilitated by newer imaging techniques, the optimal treatment of this disease remains uncertain. We describe 4 patients with severe ADEM who responded to treatment that included intensive plasmapheresis. Two of the patients were in coma at the time that plasmapheresis was instituted, and all 4 patients made an excellent recovery. Immunologic studies revealed increased serum IgA levels, increased circulating immune complex levels as measured by the Raji cell assay, and decreased numbers of T and B cells prior to treatment of ADEM. These abnormalities improved following plasma exchange. Plasmapheresis appears to be effective in reversing the neuropathologic process in ADEM. The role of this treatment modality in ADEM requires further evaluation in controlled clinical trials.

Magnetic resonance imaging in monitoring the treatment of multiple sclerosis: concerted action guidelines

Serial gadolinium enhanced MRI of the brain detects much clinically silent disease activity in early relapsing-remitting and secondary progressive multiple sclerosis (MS), and thus has an important role in monitoring the effects of therapy. Based on the proceedings of a recent Commission of the European Communities (CEC) workshop and a review of the literature, guidelines are presented for using MRI to monitor treatment trials in MS. The guidelines consider: A) MRI system and techniques; B) patient selection; C) trial design; D) analysis of results. Priorities for future research are also indicated.

Serial cerebral CT abnormalities in relapsing acute disseminated encephalomyelitis

A 7 year old girl developed acute disseminated encephalomyelitis following a Mycoplasma pneumoniae respiratory infection. The illness followed a relapsing course during the first two months. Computed tomography (CT) showed cerebral lesions of a severity and extent out of proportion to the clinical manifestations. The CT abnormalities altered with changes in her clinical state.

Cranial computed tomography in acute disseminated encephalomyelitis

Acute disseminated encephalomyelitis (ADEM) is an uncommon inflammatory disorder of the nervous system. The appearance of ADEM on cranial CT scans has rarely been reported. The author reports seven cases in two institutions during a period of seven years. Only four of the seven patients had hypodense lesions in the white matter and six patients showed spotty, nodular, or gyral enhancement after contrast injections. The enhancement resolved with steroid therapy, leaving some persistent hypoattenuated areas even after 10 months follow-up, these findings support the dual components of the pathogenesis of ADEM. The vasculitic component may be responsive to steroids, nevertheless the demyelinating or necrotic areas may not, and the latter may be responsible for the sequelae of ADEM.

Parainflammatory leukoencephalomyelitis: clinical and magnetic resonance imaging findings

Parainflammatory leukoencephalomyelitis is a broad term used to include the spectrum of disorders that affect the central nervous system following infection, immunization, or other noxious stimuli. There is a wide range of clinical and pathologic severity, ranging from acute cerebellar ataxia to acute hemorrhagic leukoencephalopathy. With the improved survival of these patients, magnetic resonance imaging provides a window to the pathologic process, which can aid in the long-term management of these patients. Although lesions of the brainstem and spinal cord correlate well to clinical symptoms, multiple cortical lesions may be present without specific localizing signs. The distribution of magnetic resonance lesions is different from that commonly seen in multiple sclerosis. In some cases, prolonged immunosuppression may be required to prevent recrudescence of the inflammatory response.

Cerebral involvement in children with acute and relapsing inflammatory polyneuropathy

We present two children with seizures and other signs of cerebral involvement at the outset of acute inflammatory demyelinating polyneuropathy, consistent with a diagnosis of encephalomyeloradiculoneuropathy. One child had a recurrence associated with mild central dysfunction and improved during therapy with corticosteroids. Both children recovered completely. Both acute and relapsing inflammatory demyelinating neuropathy may be accompanied by cerebral dysfunction, expanding the clinical spectrum of encephalomyeloradiculoneuropathy.

Aphemia as a first symptom of multiple sclerosis

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Post-infectious leukoencephalopathy as a complication of Mycoplasma pneumoniae infection

We report a 9-year-old girl with leukoencephalopathy who demonstrated serologic evidence of a Mycoplasma pneumoniae infection. She had a mild upper respiratory tract illness 10 days prior to admission and developed walking difficulty and somnolence. The neurologic symptoms progressed to semicoma and spastic paraplegia over a few days but began to improve on the fourth day. Cranial computed tomography on the eleventh day revealed an area of diffuse low density in the white matter. Cerebrospinal fluid examination was normal. The patient recovered with minimal motor deficits. Cranial computed tomography was normal. She was diagnosed as having leukoencephalopathy complicated by a Mycoplasma pneumoniae infection. The pathogenesis of this infection is believed to be an allergic reaction to Mycoplasma pneumonia of the central nervous system as well as an acute disseminated encephalomyelitis.

MRI in children with postinfectious disseminated encephalomyelitis

Acute disseminated encephalomyelitis, an inflammatory and demyelinating disorder of central nervous system white matter, typically occurs following childhood viral infections. Although CT may demonstrate abnormalities, many children have normal CT studies in spite of widespread neurologic abnormalities. We report a series of five patients with the typical clinical presentation of disseminated encephalomyelitis who were studied using magnetic resonance imaging (MRI). In each case the children presented with progressive subacute neurologic abnormalities including headache, diplopia, ataxia, hemiparesis, seizures, dysarthria, and/or coma. CT was nondiagnostic. MRI clearly demonstrated multifocal white matter lesions of the cerebrum, brainstem, and cerebellum which corresponded to clinical signs. The patients improved dramatically with corticosteroid therapy. MRI showed progressive resolution of multifocal lesions in conjunction with clinical improvement.

Acute, severe, central and peripheral nervous system combined demyelination

Acute disseminated encephalomyelopathy and Guillain-Barré syndrome are both immunologically mediated para-infectious demyelinating disorders, the former affecting the central nervous system and the latter affecting the peripheral nervous system. The term encephalo-myelo-radiculo-neuropathy was introduced to describe cases in which major involvement of one system, most commonly the peripheral, was associated with mild involvement of the other. We present a case of acute severe demyelination simultaneously affecting both the central and the peripheral nervous systems in a 10-year-old female. This clinical picture combines acute disseminated encephalomyelopathy and Guillain-Barré syndrome, both of which are extremely severe.

Acute disseminated encephalitis documented by magnetic resonance imaging and computed tomography. Report of a case

A 16-year-old girl developed left hemispheric deficits, which were followed by clouding of consciousness, quadriplegia, and subcortical blindness. Although we could not demonstrate a recent viral infection, the clinical features, laboratory and radiologic findings strongly suggested the diagnosis acute disseminated encephalitis. Cerebrospinal fluid abnormalities incompletely correlated with the clinical course. In contrast, X-ray computed tomography and particularly magnetic resonance imaging of the head closely reflected disease and improvement.

Magnetic resonance imaging in childhood disseminated encephalomyelitis

We report the magnetic resonance imaging features in two children with post-infectious disseminated encephalomyelitis. Magnetic resonance imaging dramatically demonstrated multiple white matter lesions in both children and resolution of lesions in conjunction with clinical recovery. These cases indicate that magnetic resonance imaging has considerable diagnostic utility in disseminated encephalomyelitis of childhood.