Paediatric acute haemorrhagic leukoencephalitis

We report a case of a preschool age girl, previously healthy, referred to our hospital on ventilatory support with a history of vomiting, headache, and rapid neurological worsening within 24 hours in the form of seizures, encephalopathy and loss of consciousness. On presentation, she was deeply comatose with dilated non-reactive pupils, absent brainstem reflexes and flaccid quadriplegia. Diagnosis of acute haemorrhagic leukoencephalitis was considered based on laboratory and neuroimaging findings. MRI of the brain showed fluffy white matter hyperintensities and microhaemorrhages in bilateral cerebral hemispheres and thalami. Aggressive treatment with methylprednisolone, plasmapheresis and intravenous immunoglobulin showed dramatic improvement with no neurological sequelae. Our case is unique in a way that despite the hyperacute onset and rapid deterioration, with a fulminant course in the intensive care unit, the child recovered dramatically with aggressive management.

Acute Disseminated Encephalomyelitis and Acute Hemorrhagic Leukoencephalitis Following COVID-19: Systematic Review and Meta-synthesis

BACKGROUND AND OBJECTIVES

Since the onset of the COVID-19 pandemic, a growing number of reports have described cases of acute disseminated encephalomyelitis (ADEM) and acute hemorrhagic leukoencephalitis (AHLE) following infection with COVID-19. Given their relatively rare occurrence, the primary objective of this systematic review was to synthesize their clinical features, response to treatments, and clinical outcomes to better understand the nature of this neurologic consequence of COVID-19 infection.

METHODS

Patients with a history of COVID-19 infection were included if their reports provided adequate detail to confirm a diagnosis of ADEM or AHLE by virtue of clinical features, radiographic abnormalities, and histopathologic findings. Cases purported to be secondary to vaccination against COVID-19 or occurring in the context of a preexisting relapsing CNS demyelinating disease were excluded. Case reports and series were identified via PubMed on May 17, 2021, and 4 additional cases from the authors' hospital files supplemented the systematic review of the literature. Summary statistics were used to describe variables using a complete case analysis approach.

RESULTS

Forty-six patients (28 men, median age 49.5 years, 1/3 >50 years old) were analyzed, derived from 26 case reports or series originating from 8 countries alongside 4 patient cases from the authors' hospital files. COVID-19 infection was laboratory confirmed in 91% of cases, and infection severity necessitated intensive care in 67%. ADEM occurred in 31 cases, whereas AHLE occurred in 15, with a median presenting nadir modified Rankin Scale score of 5 (bedridden). Anti-MOG seropositivity was rare (1/15 patients tested). Noninflammatory CSF was present in 30%. Hemorrhage on brain MRI was identified in 42%. Seventy percent received immunomodulatory treatments, most commonly steroids, IV immunoglobulins, or plasmapheresis. The final mRS score was ≥4 in 64% of patients with adequate follow-up information, including 32% who died.

DISCUSSION

In contrast to ADEM cases from the prepandemic era, reported post-COVID-19 ADEM and AHLE cases were often advanced in age at onset, experienced severe antecedent infection, displayed an unusually high rate of hemorrhage on neuroimaging, and routinely had poor neurologic outcomes, including a high mortality rate. Findings are limited by nonstandardized reporting of cases, truncated follow-up information, and presumed publication bias.

Genetic Acute Necrotizing Encephalopathy Associated with RANBP2: Clinical and Therapeutic Implications in Pediatrics

Genetic (also known as familial) acute necrotizing encephalopathy (ANE1) is a rare disease presenting with encephalopathy often following preceding viral febrile illness in patients with a genetic predisposition resulting from a missense mutation in the gene encoding RAN Binding Protein 2 (RANBP2). The acute episode is characterized by deterioration in consciousness, often with focal neurologic deficits and seizures. Additionally, symmetric multifocal brain lesions are seen in the bilateral thalami as well as other characteristic regions, involving both gray and white matter. Prognosis is variable, with a high mortality rate and most surviving patients having persistent neurologic deficits. Early treatment with high dose steroids is associated with a more favorable outcome, however the diagnosis is often overlooked resulting in delayed treatment. The RANBP2 mutation associated with ANE1 causes an incompletely penetrant predisposition to encephalopathy in the setting of febrile illness through a mechanism that remains elusive. There are several non-mutually exclusive hypotheses suggesting possible etiologies for this phenotype based on the many functions of RANBP2 within the cell. These include dysfunctions in nucleocytoplasmic trafficking and intracellular metabolic regulation, as well as cytokine storm, and abnormal distribution of mitochondria. This narrative review explores these key concepts of the RANBP2 mutation and its clinical and therapeutic implications in pediatric populations.

Anti-CV2/CRMP5 antibody-associated hemorrhagic leukoencephalomyelitis treated with steroids, intravenous immunoglobulin, plasmapheresis, and cyclophosphamide

Anti-CV2 or anti-collapsing response-mediator protein-5 (CRMP5) autoantibodies (anti-CV2/CRMP5-Ab) are associated with various paraneoplastic neurological disorders. The best therapy is typically removal of the underlying cancer. We describe a previously healthy elderly male who had no known malignancy. He presented with a demyelinating encephalomyelitis and later developed hemorrhagic changes on neuroimaging. He was treated with intravenous immunoglobulin (IVIG), intravenous steroids, and plasmapheresis; however, sustained clinical and radiographic stabilization and improvement only occurred following cyclophosphamide. He unexpectedly died of a cardiac arrest. postmortem, his serum paraneoplastic screen was found to be weakly positive for anti-CV2/CRMP5-Ab.

Weston-Hurst syndrome with acute hemorrhagic cerebellitis

Weston-Hurst syndrome is an exceptional variant of ADEM characterized by brain hemorrhages. Lesions are usually supratentorial and death is a usual outcome. We report a cerebellar Weston-Hurst syndrome early treated by craniectomy, steroids and plasma exchange. This is the first case of infratentorial Weston-Hurst syndrome associated with a favorable outcome.

Serial outcomes in acute necrotising encephalopathy of childhood: A medium and long term study

OBJECTIVE

Acute necrotising encephalopathy (ANEC) is a severe, debilitating childhood disorder. We used the ANEC scoring system (ANE-ss) and standardised neurodevelopmental scores to objectively characterise medium and long term outcomes.

METHODS

Retrospective review of children with ANEC at KK Women's and Children's Hospital, Singapore, from 2005 to 2012. ANE-ss was determined from clinical features and neuroimaging, and neurodevelopmental scores (Pediatric Glasgow Outcome Scale Extended, Pediatric Cerebral Performance Category scale and Pediatric Overall Performance Category scale) were applied at 1, 6, 12 and 24months post diagnosis.

RESULTS

Seven patients with ANEC were studied. All had a viral prodrome with fever, and encephalopathy at presentation, and received immunotherapy (steroids or immunoglobulin). ANE-ss scores were medium risk in 4 patients and high risk in 3 patients. One died (high risk ANE-ss) and outcome was determined in the 6 survivors. At 1month post diagnosis, 3 patients (50%) were mildly affected and 3 (50%) were severely affected. Morbidity rates improved by 12months, with 67% and 33.3% scoring in the mildly affected and severely affected ranges, respectively. Medium risk patients did well with majority having little or no neurological deficits and good outcome scores.

CONCLUSION

Mortality and severe morbidity correlated well with high risk ANE-ss. However, our patients with medium risk ANE-ss had good neurodevelopmental sequelae. Serial disability scoring is useful in evaluating the progress of ANEC patients on follow up. Assessment at 1month post diagnosis can aid prognostication of long term outcome.

Post-infectious encephalitis in adults: diagnosis and management

Many important central nervous system (CNS) syndromes can develop following microbial infections. The most severe forms of post-infectious encephalitis include acute disseminated encephalomyelitis (ADEM), acute hemorrhagic leukoencephalitis and Bickerstaff's brainstem encephalitis. ADEM is an inflammatory demyelinating disorder of the CNS. It typically follows a minor infection with a 2–30 days latency period and is thought to be immune-mediated. It is clinically characterized by the acute onset of focal neurological signs and encephalopathy. Patients can require intensive care unit admission because of coma, seizures or tetraplegia. Cerebrospinal fluid analysis usually shows lymphocytic pleocytosis but, unlike viral or bacterial encephalitis, no evidence of direct CNS infection is found. There are no biologic markers of the disease and cerebral magnetic resonance imaging is essential to diagnosis, detecting diffuse or multifocal asymmetrical lesions throughout the white matter on T2- and FLAIR-weighted sequences. High-dose intravenous steroids are accepted as first-line therapy and beneficial effects of plasma exchanges and intravenous immunoglobulins have also been reported. Outcome of ADEM is usually favorable but recurrent or multiphasic forms have been described.

Use of therapeutic plasma exchange in the management of acute hemorrhagic leukoencephalitis: a case report and review of the literature

BACKGROUND

Acute hemorrhagic leukoencephalitis (AHLE) is a rare, fatal, central nervous demyelinating disease characterized by a rapid fulminant clinical course. Successful management requires early diagnosis, aggressive management of cerebral edema, and immunosuppression. Therapeutic plasma exchange (TPE) is infrequently used and commences after initial management fails.

CASE REPORT

A 31-year-old man presented with right arm weakness, whose symptoms rapidly progressed to hemiplegia and aphasia. The patient was initially managed with glucocorticosteroids. Decompressive craniotomy and brain biopsies were performed when his intracranial pressure increased. Brain biopsy findings were consistent with AHLE. Mycoplasma pneumonia immunoglobulin G and immunoglobulin M serologies revealed recent infection. Despite surgical and medical management, he decompensated on Day 11, and TPE was initiated. The patient received a total of 10 TPE treatments. On the fourth day of TPE treatment, he was extubated. Twenty-one days after TPE began, he was ambulating with near normal muscle strength and was discharged. Four months after initial presentation, the patient has normal strength and is working full-time.

CONCLUSIONS

AHLE has a fulminant course requiring accurate and rapid diagnosis. Successful therapy requires aggressive management of intracranial pressure and immunosuppression. Two other reports of AHLE document successful management with TPE. Each of these patients survived with minimal neurologic impairments. Given the likely immune-mediated nature of this disease, combined treatment of steroids, surgery, and TPE may lead to shorter hospital stays and improved neurologic outcomes. Clinical studies are needed to further study the effect of TPE on neurologic outcome in AHLE.

A medical overview of encephalitis

Encephalitis is uncommon but is a neurological emergency which must be considered in a patient presenting with altered consciousness. Encephalitis is a diffuse inflammatory process of the brain parenchyma associated with evidence of brain dysfunction. The presentation of encephalitis can be acute or chronic. The aetiology of encephalitis can be broadly divided into two major subtypes. (1) Infection-related encephalitis which is a direct consequence of pathogenic viral, bacterial or parasitic agents. Herpes simplex virus (HSV) and varicella-zoster virus (VZV) are the most common cause of acute infectious encephalitis. (2) Autoimmune-mediated encephalitis which is mediated by an aberrant immune response. This can be triggered by a recent viral infection or vaccination. An example of this would be acute disseminated encephalitis (ADEM). This article will focus on the medical management of acute encephalitis. This will involve an extensive overview of the literature reviewing the diagnosis, investigation and treatment of acute viral encephalitis, ADEM and acute haemorrhagic leukoencephalopathy (AHLE). Encephalitis can also present chronically, and some of the different types of chronic encephalitis will be discussed.

Treatment leading to dramatic recovery in acute hemorrhagic leukoencephalitis

The clinical course, neuroimaging, neuropathological features, and management of a 7-year-old girl with acute hemorrhagic leukoencephalitis are reported. Treatment with subtotal bifrontal craniectomies for symptoms of imminent uncal herniation followed by high-dose corticosteroid therapy was associated with dramatic clinical recovery. This report highlights the utility of aggressive intervention in acute hemorrhagic leukoencephalitis, an otherwise fatal disorder.

Acute necrotizing encephalopathy: combined therapy and favorable outcome in a new case

BACKGROUND

Acute necrotizing encephalopathy (ANE) is a rare disease characterized by multiple, symmetrical brain lesions, affecting thalami, brainstem tegmentum, and cerebellar medulla; more inconstantly, other structures are involved, i.e., internal capsules, posterolateral putamen, and deep periventricular white matter.

FEATURES

The clinical picture consists of rapidly deteriorating acute monophasic encephalopathy preceded by prodromal febrile illness; the symptoms include hyperpyrexia, convulsions, recurrent vomiting, and coma within 24 h.

PROGNOSIS

The outcome is usually poor and approximately 70% of the patients die within a few days from the onset of fever. There is no specific therapy for ANE but, in some patients, the clinical status improved with steroid treatment.

Acute necrotizing encephalopathy associated with hemophagocytic syndrome

A 7-year-old female suddenly exhibited high fever and convulsions, and entered a semi-coma. She also had thrombocytopenia, elevated aminotransferase, prolonged prothrombin time and activated partial thromboplastin time, and hemophagocytes in the bone marrow. The brain magnetic resonance imaging revealed multiple low-intensity areas on the T1-weighted images, and high-intensity areas on the T2-weighted images bilaterally in the thalamus, the dorsal part of the pons, and the cerebellar white matter. The patient was diagnosed as having both acute necrotizing encephalopathy and hemophagocytic syndrome. Serum and cerebrospinal fluid interleukin-6 and tumor necrosis factor-alpha were elevated to the same high levels (serum:cerebrospinal fluid interleukin-6, 103:101 pg/mL; tumor necrosis factor-alpha 753:753 pg/mL). The clinical symptoms and the magnetic resonance imaging findings improved immediately after the administration of dexamethasone. These results suggest that the hypercytokinemia and the hyperpermeability of both the blood-brain barrier and the capillary walls of the central nervous system might be essential in the pathogenesis of acute necrotizing encephalopathy, and that early steroid therapy might be effective in these conditions.

Reversible spongiform leucoencephalopathy after inhalation of heated heroin

OBJECTIVE

To describe the clinical course and imaging findings in a young man who developed a spongiform leucoencephalopathy from heroin-vapour inhalation, and to discuss the treatments which may have contributed to the unexpected favourable outcome in this case.

DESIGN

Case report.

SETTING

Intensive care unit of a university teaching hospital.

PATIENT

A patient who developed a near fatal toxic leucoencephalopathy with impressive clinical recovery and reversible white matter changes on imaging.

MEASUREMENTS AND RESULTS

Successive computed tomography scans and magnetic resonance imaging over 7 months showed evolution from bilateral extensive involvement of the cerebral white matter to almost complete resolution accompanied by the development of periventricular lesions suggestive of necrosis. Despite the fact that the patient had stretching spasms for several days, the outcome was favourable with prolonged supportive care and antioxidant therapy by ubiquinone (coenzyme Q).

CONCLUSION

This case demonstrates that prolonged intensive care is of paramount importance in patients with spongiform leucoencephalopathy after inhalation of heated heroin, that abnormalities of cerebral white matter may be slowly regressive, and supports the use of coenzyme Q in severe forms of the disease.

Acute onset of hemorrhagic leukoencephalomyelitis (Hurst) in the spinal cord

Acute hemorrhagic leukoencephalomyelitis is considered to be a rare autoimmune disorder. The present case, a 34-year-old male, developed non-specific symptoms 3 weeks after surgical removal of his meniscus and following an inconspicuous infection of the upper respiratory tract. The spinal cord was the first to be affected, followed by symptoms of headache, nausea and fever which reached 39.4 degrees C. Autopsy revealed acute hemorrhagic leukoencephalomyelitis with marked involvement of the spinal cord. Diagnosis was established by histopathological examination of the brain and spinal cord. This is the first description of the onset of this disease in the spinal cord.

Post-infectious central and peripheral nervous system diseases complicating Mycoplasma pneumoniae infection. Report of three cases and review of the literature

Three patients with a central and peripheral nervous system disease complicating a Mycoplasma pneumoniae (M. pn.) infection are presented. Patient 1 suffered from bilateral optic neuritis as well as acute Guillain-Barré syndrome recovering after plasmapheresis. The two other patients suffered from severe haemorrhagic leukoencephalitis (Hurst) which only could be contained by aggressive decompressive craniectomy with duraplasty. All three illnesses were clearly shown to be associated with M. pn. infection. Our three patients represent the full scale of central nervous (CNS) (cerebral and myelitic) as well as peripheral nervous system (PNS) (GBS, optic neuritis) manifestation of a disease caused by the same pathogenetic - post-infectious - mechanism; pathogenic CNS and PNS epitopes might be shared in post-infectious neurological disease following M. pn. infection.

Multiple sclerosis, acute disseminated encephalomyelitis, and related conditions

Multiple sclerosis (MS) and acute disseminated encephalomyelitis (ADEM) are conditions whose closely related pathology suggests shared pathophysiological elements, but whose clinical courses are usually, but not always quite dissimilar. The former is largely a disease of adulthood, the latter of childhood. Optic neuritis, demyelinative transverse myelitis, and Devic's syndrome are neurological syndromes that may occur as manifestations of either MS or ADEM. Patients with Miller-Fisher syndrome and encephalomyelradiculoneuropathy usually have features suggesting ADEM in combination with acute demyelinative polyneuropathy. These various conditions and other forms of ADEM share an indistinct border with encephalitides, granulomatous, and vasculitic conditions. MS, ADEM, and the pertinent syndromic subtypes, their differential diagnosis, treatment, and prognosis are considered in this review. Acute cerebellar ataxia is a syndrome that is likely to be pathophysiologically distinct from ADEM, although its occurrence as a postinfectious illness suggests a distant kinship. It is also reviewed.

[A case of acute necrotizing encephalopathy of childhood with a good outcome]

We experienced a case of acute necrotizing encephalopathy of childhood with a good outcome. The disease continued for about three weeks, and the patient recovered with a sequela of mild left-hemiparesis. On the brain magnetic resonance imaging, abnormal intensity areas in the thalamus and putamen reduced size at an early stage of the disease. After 1 year, his mental and motor development seemed to be almost normal, but brain single photon emission computed tomography and electroencephalography were abnormal. Subclinical functional abnormalities persisted longer than had been expected.

Inflammatory diseases of the central nervous system in dogs

Inflammatory diseases of the central nervous system (CNS) are important causes of seizures in dogs. Specific diseases include canine distemper, rabies, cryptococcosis, coccidioidomycosis, toxoplasmosis, neosporosis, Rocky Mountain spotted fever, ehrlichiosis, granulomatous meningoencephalomyelitis, and pug dog encephalitis. Inflammatory disorders should be considered when a dog with seizures has persistent neurological deficits, suffers an onset of seizures at less than 1 or greater than 5 years of age, or exhibits signs of systemic illness. A thorough history, examination, and analysis of cerebrospinal fluid are important in the diagnosis of inflammatory diseases. However, even with extensive diagnostic testing, a specific etiology is identified in less than two thirds of dogs with inflammatory diseases of the CNS.

[Acute Weston Hurst necrotizing hemorrhagic leukoencephalitis]

The clinical and pathological findings of a 43-year-old woman, diagnosed as having acute hemorrhagic leukoencephalitis at postmortem examination, are presented. The acute hemorrhagic leukoencephalitis affects mainly young adults and is the most fulminant from of demyelinating disease. It is frequently preceded by a respiratory infection. Diagnosis is facilitated by CT scanning and MRI, which reveal the massive lesion in the cerebral white matter. Many cases terminate fatally in 2 or 4 days, but in others survival is longer. The pathological findings are distinctive.