MRI findings in acute cerebellitis

Acute Cerebillitis Due to Salmonella typhimurium Infection in an Adult: A Report of an Unusual Case

Acute cerebellitis is an inflammatory illness that may manifest as a primary, para-infectious, or post-infectious disease. The clinical manifestations of acute cerebellitis are traditionally characterized by fever, vomiting, headache, and altered sensorium, accompanied by impaired cerebellar function corroborated by neuroradiography alterations. Acute cerebellitis may lead to a potentially fatal increase in pressure within the skull, requiring immediate and critical neurosurgical surgery. It is important to note that cerebellar symptoms may not be evident initially. This report provides a comprehensive analysis of a case of a 57-year-old male patient who had been diagnosed with acute cerebellitis caused by an infection with Salmonella typhimurium.

Pseudotumoral hemicerebellitis in a young male sailor with complete recovery after steroid therapy

Pseudotumoral hemicerebellitis is a rare presentation of acute cerebellitis, which involves the inflammation of a single cerebellar hemisphere and most commonly affects children. It mimics a tumor on imaging, hence given the name. In this report, we present a case of pseudotumoral hemicerebellitis in a 30-year-old male who presented to the emergency room (ER) with complaints of vertigo, vomiting, and a headache.

Acute cerebellitis following COVID-19 vaccination: A case report

A plethora of neurological symptoms have been reported as the side effects of COVID-19 vaccines. Vaccine-associated acute cerebellitis is quite rare. Here, we report a 45-year-old female with acute onset cerebellitis, beginning 10 days after administration of Sinopharm vaccine. The patient's CSF COVID-19 PCR was found to be positive, with no pulmonary symptoms.

Diagnosing viral encephalitis and emerging concepts

PURPOSE OF REVIEW

This review offers a contemporary clinical approach to the diagnosis of viral encephalitis and discusses recent advances in the field. The neurologic effects of coronaviruses, including COVID-19, as well as management of encephalitis are not covered in this review.

RECENT FINDINGS

The diagnostic tools for evaluating patients with viral encephalitis are evolving quickly. Multiplex PCR panels are now in widespread use and allow for rapid pathogen detection and potentially reduce empiric antimicrobial exposure in certain patients, while metagenomic next-generation sequencing holds great promise in diagnosing challenging and rarer causes of viral encephalitis. We also review topical and emerging infections pertinent to neuroinfectious disease practice, including emerging arboviruses, monkeypox virus (mpox), and measles.

SUMMARY

Although etiological diagnosis remains challenging in viral encephalitis, recent advances may soon provide the clinician with additional tools. Environmental changes, host factors (such as ubiquitous use of immunosuppression), and societal trends (re-emergence of vaccine preventable diseases) are likely to change the landscape of neurologic infections that are considered and treated in clinical practice.

A Novel Radiological Score System to Assess the Clinical Severity in Patients with Acute Cerebellitis

To develop a radiological score system to assess the severity of acute cerebellitis (AC) and to compare radiological severity score at the onset to cerebellar atrophy at follow-up. Clinical and MRI findings were recorded in 16 patients with AC. Radiological severity score considering topographic patterns, gray/white matter involvement, enhancement, tonsillar herniation or hydrocephalus development and clinical severity score taking into account clinical symptoms were assessed for each patient at the onset of the symptoms. Radiological and neurological sequelae were assessed at follow-up. At symptoms onset, clinical severity scale ranged from mild to severe and radiological severity score ranged from 3 to 7 with higher scores indicating a greater severity. The cut-off value of 5 for radiological score well segregated severe patients defined by clinical scale. A significant correlation between clinical scale and radiological severity scores (p < 0.001, r = 0.75) was found. At follow-up visit, all children developed cerebellar atrophy and 5 children showed neurologic sequelae while adults showed complete resolution without atrophy. Patients in whom atrophy was not observed had both older ages (p < 0.001) and a focal cerebellar involvement (p = 0.03). In patients with AC, radiological severity score may be a useful tool in evaluating clinical severity, but it is not capable to predict neither neurological sequelae nor evolution towards atrophy. Cerebellar atrophy, observed in children with AC, may be caused by several factors such as the age of patient and the extension of cerebellar involvement and it may be counterbalanced by neuronal restoring processes due to neuroplasticity.

Postinfectious coronavirus disease 2019 hemorrhagic cerebellitis: illustrative case

BACKGROUND

Conditions that can mimic posterior fossa tumors are rare. Their identification is crucial to avoid unnecessary surgical intervention, especially when prompt initiation of medical therapy is critical.

OBSERVATIONS

The authors presented a case of pseudotumoral hemorrhagic cerebellitis in a 3-year-old boy who presented initially with headache, persistent vomiting, and decreased level of consciousness 9 weeks after severe acute respiratory syndrome coronavirus 2 infection. Magnetic resonance imaging showed a left cerebellar hemorrhagic mass–like lesion with edema and mild hydrocephalus. The patient responded to high-dose steroids and was discharged 2 weeks later with complete recovery.

LESSONS

When evaluating patients with possible tumor syndromes, it is important to also consider rarer inflammatory syndromes that can masquerade as neoplasms. Postinfectious hemorrhagic cerebellitis is one such syndrome.

Can MRI Differentiate between Infectious and Immune-Related Acute Cerebellitis? A Retrospective Imaging Study

BACKGROUND AND PURPOSE

Acute cerebellitis is an acute neurologic condition attributable to a recent or concurrent infection or a recent vaccination or ingestion of medication, with MR imaging evidence of cerebellar edema. MR imaging can confirm an anatomic abnormality and may allow the radiologist to establish a differential diagnosis. The purpose of this research was to evaluate the MR imaging findings in children with acute cerebellitis due to infectious versus immune-related conditions, in particular whether MR imaging findings allow differentiation.

MATERIALS AND METHODS

Electronic medical records were reviewed between 2003 and 2020 in our quaternary children's hospital. Data included demographics and clinical records: presentation/symptoms, final diagnosis including acute cerebellitis and immune-related acute cerebellitis, length of stay, treatment, condition at discharge, and laboratory findings. Retrospective independent review of all brain MR imaging studies was performed.

RESULTS

Forty-three patients (male/female ratio, 28:15) were included in this study. Average age at presentation was 7.08 years (range, 0.05-17.52 years). Thirty-five children had infectious and 8 children had immune-related acute cerebellitis. Significant differences in neuroimaging were the following: 1) T2-FLAIR hyperintense signal in the brainstem (37.50% versus 2.85%, P = .016); 2) T2-FLAIR hyperintense signal in the supratentorial brain higher in the immune-related group (37.50% versus 0.00%, P = .004); and 3) downward herniation, higher in the infectious acute cerebellitis group (42.85% versus 0.00%, P = .03).

CONCLUSIONS

Acute cerebellitis is a rare condition, and MR imaging is helpful in the differential diagnosis. T2-FLAIR hyperintense signal in the brainstem and supratentorial brain may be indicative of immune-related acute cerebellitis, and downward herniation may be indicative of infectious acute cerebellitis.

Acute cerebellitis following SARS-CoV-2 infection: A case report and review of the literature

Novel coronavirus disease (COVID‐19) first described in Wuhan, China in December 2019, has rapidly spread across the world and become a global public health emergency. Literature on the neurological manifestations of COVID‐19 is limited. We report a 24‐year‐old male, who presented with vertigo, dysarthria, and bradyphrenia 3 weeks after being diagnosed with COVID‐19 on nasopharyngeal reverse transcription polymerase chain reaction. The patient was diagnosed with acute cerebellitis based on magnetic resonance imaging features and showed improvement posttreatment with intravenous methylprednisone for 5 days. The scope of this article is to highlight the importance of early identification of neurological symptoms and timely management as the outcomes may be catastrophic.

A Case of Influenza Virus-Induced Acute Cerebellitis Treated with Steroid Pulse Therapy

Acute cerebellitis (AC) is characterized by acute onset cerebellar ataxia brain magnetic resonance imaging (MRI) abnormalities of the cerebellum. The most common cause of AC is viral infection, and some patients with AC experience neurological sequelae. AC associated with influenza virus is extremely rare, and its prognosis and treatment are unknown. We present the case of a 2-year-old boy with influenza virus-induced AC who was treated with pulse steroid therapy. The patient presented with fever, anorexia, vomiting, malaise, altered consciousness, truncal ataxia, dysmetria, and dysarthria. He was diagnosed with influenza using a nasopharyngeal antigen test. Brain MRI showed hyperintense T2 and diffusion-weighted signal abnormalities in the cerebellar white matter and dentate nuclei bilaterally. The patient was treated with two courses of pulse methylprednisolone therapy and recovered completely in 2 months after the onset. The prognosis of AC is poorer than that of acute cerebellar ataxia, which shows similar symptoms to AC with normal brain MRI. The type of virus might also be associated with the prognosis of AC. Literature review showed that one of the five cases (including the present case, 20%) reported with influenza-associated AC was noted to have neurological sequelae, which might be more severe than those of varicella-zoster-related AC. Given that the pathogenesis of AC is assumed to be immune-mediated, pulse methylprednisolone therapy might be a good option for the treatment of influenza virus-induced AC.

Effects of systemic corticosteroid treatment on pseudotumoral hemicerebellitis: a case report and literature review

PURPOSE

Pseudotumoral hemicerebellitis is an acute, unilateral inflammation of the cerebellum that typically affects the pediatric population. The purpose of this paper is to review cases of pseudotumoral hemicerebellitis in the literature and evaluate if treatment with systemic corticosteroids reduces length of time to symptomatic recovery.

METHODS

We present a case report of a 12-year-old male with pseudotumoral hemicerebellitis and unilateral cerebellar dysfunction. Additionally, we review the thirty-five reported cases of pseudotumoral hemicerebellitis with respect to length of time to symptomatic recovery with or without systemic corticosteroid treatment.

RESULTS

Thirty cases reported length of time to symptomatic recovery. Including our case, the mean time to recovery for those treated with systemic corticosteroids (n = 20) was 48.05 days (SE = 16.3). The mean time to recovery for those treated without (n = 10) was 86.7 days (SE = 29.3).

CONCLUSIONS

Treatment with systemic corticosteroids was associated with a faster time to symptomatic recovery compared to without. Regardless of etiology, reducing inflammation and mass effect involved in pseudotumoral hemicerebellitis may be integral to a more rapid return to neurological baseline.

Magnetic Resonance Imaging in Peripartum Encephalopathy: A Pictorial Review

Acute neurological problems are significant disorders of pre- and postpartum period in women. We analyzed the magnetic resonance imaging (MRI) profile of patients presenting with peripartum encephalopathy over 2 years. Of 51 patients, MRI was abnormal in 40 patients and normal in 11 patients. Posterior reversible encephalopathy (13/40), cerebral venous thrombosis (6/40), and postpartum angiopathy (3/40) are the three most common causes of peripartum encephalopathy as identified in MRI. The other less common but important etiology include HELLP (Hemolysis, Elevated Liver enzymes and Low Platelet) syndrome (2), osmotic demyelination (2), antiphospholipid syndrome (2), tubercular meningitis/cerebritis (3), pituitary hyperplasia with hemorrhage (2), postictal edema (2), cerebellitis (1), transient splenial lesion (1), and changes of old trauma and stroke (one each).

Pediatric Fulminant Cerebellitis Is Still a Fatal Disease that We Know Little About! Two Case Reports and a Literature Review

Case series

Patients: Male, 13-year-old • Female, 14-year-old

Final Diagnosis: Fulminant cerebellitis • obstructive hydrocephalus

Symptoms: Headache • unconsciousness

Medication: —

Clinical Procedure: V-P Shunt for congenital hedrocephalus

Specialty: Critical Care Medicine • Immunology • Infectious Diseases • Pediatrics and Neonatology • Radiology

Cerebellitis as a rare manifestation of scrub typhus fever

Scrub typhus is a mite-borne rickettsial disease caused by Orientia tsutsugamushi, a gram-negative coccobacilli transmitted through the bite of chigger mite. Scrub typhus has diverse clinical manifestations, often presenting either as a simple febrile illness or as a complicated multi-organ dysfunction. Neurological complications in scrub typhus are diverse but their exact incidence is unknown. Cerebellitis is another rare neurological manifestation associated with scrub typhus. Here, we report the case of a 26-year-old woman with serologically confirmed scrub typhus presenting with fever and gross cerebellar dysfunction. MRI was normal. She was managed with antimicrobials and made an uneventful recovery.

Wernekink commissure syndrome secondary to a rare 'V'-shaped pure midbrain infarction: a case report and review of the literature

Purpose: Wernekink commissure syndrome is a typical but extremely rare mesencephalic syndrome, and generally presents with bilateral cerebellar dysfunction, diverse oculomotor disorders and occasionally delayed-onset palatal myoclonus or tremor. However, it has been reported infrequently.Methods: We report a case of a 55-year-old man who suffered an acute paramedian midbrain infarction presenting with bilateral cerebellar ataxia, bilateral anterior internuclear ophthalmoplegia and unilateral pseudoabducens palsy, which is confirmed as Wernekink commissure syndrome by magnetic resonance imaging (MRI). We summarized the clinical data of this entity and performed a literature review of 20 previous reports of patients with this syndrome.Results: In combination with previous reports, we found that the most common symptom was bilateral cerebellar ataxia (100%) and other frequent symptoms were oculomotor disorders (81%), delayed palatal myoclonus or tremor (33%) and consciousness dysfunction (33%). Lesions on brain MRI of all patients affected the area of caudal paramedian midbrain (CPM).Conclusion: Bilateral cerebellar ataxia and lesions involved in the area of CPM on MRI are the major features of Wernekink commissure syndrome and should be the necessary conditions of diagnostic criteria. The simultaneous occurrence of bilateral cerebellar ataxia and oculomotor disorders is significant for localization diagnosis. Consciousness dysfunction is also a relatively frequent symptom of this syndrome. Moreover, pseudoabducens palsy might be attributed to a midbrain lesion. Clinicians should be familiar with and early to recognize this unique syndrome to avoid misdiagnosis.

Herpes simplex virus-1 as a rare etiology of isolated acute cerebellitis: case report and literature review

Acute cerebellitis is one of the most common cerebellar disorders and occurs due to para-infectious, post-infectious, or post-vaccination cerebellar inflammation. Herpes simplex virus-1 (HSV-1) is known as a common infectious cause of sporadic encephalitis. Cerebellar involvement of HSV-1 is rare and almost always associated with meningoencephalitis. To date, HSV-1 has been identified as the cause of acute isolated cerebellitis in only two patients. Here we report another case of isolated acute cerebellitis caused by HSV-1 in a 20-month-old boy.

Acute Cerebellitis in Children: A Variable Clinical Entity

Acute cerebellar ataxia is the most common cause of acute ataxia in children and it usually runs a self-limiting and ultimately benign clinical course. A small proportion of children have evidence of inflammatory swelling in the cerebellum. Many of these children suffer more severe and potentially life-threatening forms of cerebellar ataxia and may need more intensive treatments including urgent neurosurgical treatments. This more severe form of acute cerebellar ataxia is often termed acute cerebellitis. Many children with acute cerebellitis have long-term neurological sequela and evidence of structural cerebellar changes on follow-up imaging. Several patterns of cerebellar inflammation have been described. The authors describe the variabilities in the clinical and radiological patterns of disease in the cases that have been described in the literature.

Cerebellar Ataxia in Children: A Clinical and MRI Approach to the Differential Diagnosis

: The cerebellum has long been recognized as a fundamental structure in motor coordination. Structural cerebellar abnormalities and diseases involving the cerebellum are relatively common in children. The not always specific clinical presentation of ataxia, incoordination, and balance impairment can often be a challenge to attain a precise diagnosis. Continuous advances in genetic research and moreover the constant development in neuroimaging modalities, particularly in the field of magnetic resonance imaging, have promoted a better understanding of cerebellar diseases and led to several modifications in their classification in recent years. Thorough clinical and neuroimaging investigation is recommended for proper diagnosis. This review outlines an update of causes of cerebellar disorders that present clinically with ataxia in the pediatric population. These conditions were classified in 2 major groups, namely genetic malformations and acquired or disruptive disorders recognizable by neuroimaging and subsequently according to their features during the prenatal and postnatal periods.

Immune-mediated disorders

Paraneoplastic and autoimmune encephalitis comprise a group of immune-mediated disorders that are associated with different immune effector mechanisms. Classic paraneoplastic neurologic syndromes are triggered by an antitumor immune response. The disease is considered to result from a T-cell response; in addition, patients harbour high titers of autoantibodies against intracellular antigens that are considered as epiphenomenon but are useful diagnostic markers. Neuropathology consists of T-cell-dominated inflammation, marked neuronal loss, and microglial activation with upregulation of HLA-DR. In the last decade, an increasing number of diseases associated with autoantibodies against neuronal surface antigens have been described. There is strong evidence that these autoantibodies are pathogenic and the associated syndromes are generally termed as antineuronal autoimmune encephalitis. Patients typically present with limbic, multifocal, or diffuse encephalitis and respond to immunotherapy. Neuropathologic descriptions are restricted to few biopsy and autopsy specimens and show mild inflammatory infiltrates and microglial activation, together with reduced expression of the respective target antigens, immunoglobulin deposits, and a variable degree of complement activation. Other putative autoimmune disorders of the central nervous system include, among others, Rasmussen encephalitis, chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS), acute cerebellitis, Susac syndrome, and Hashimoto encephalitis. While pathologic studies suggest an immune-mediated disease for Rasmussen encephalitis, CLIPPERS, acute cerebellitis, and Susac syndrome, neuropathologic descriptions of Hashimoto encephalitis are rare and the pathogenesis deserves further study.

An Unusual Case of Dizziness Presenting to Emergency Department: Acute Cerebellitis

Acute cerebellitis is an uncommon and potentially fatal disease which usually presents initially with non-specific symptoms. There is scarce report on local cases of isolated acute cerebellitis. We report a patient with isolated acute cerebellitis attending emergency department with predominant symptom of dizziness. Diagnosis was made by magnetic resonance imaging assisted by lumbar puncture. He received timely medical treatment and the clinical course was benign. The clinical feature, diagnosis, and managements of acute cerebellitis are discussed.

Acute cerebellitis in adults: a case report and review of the literature

Background

Acute cerebellitis is a rare disease with the majority of cases described in children. Little is known about the clinical characteristics and outcome in adults.

Case presentation

A 37-year-old Caucasian woman presented with headache, nausea, and photophobia, and was diagnosed as having a migraine attack. Two days later, she subsequently returned with aggravated headache, dysarthria and horizontal nystagmus. Magnetic resonance imaging (MRI) showed a swollen cerebellum and hydrocephalus and the patient was diagnosed with acute cerebellitis. Cerebrospinal fluid (CSF) examination showed an elevated leukocyte count and protein. Blood serology showed the presence of immunoglobulin M and immunoglobulin G for both Epstein–Barr virus and cytomegalovirus. The patient was treated with dexamethasone and discharged to a rehabilitation center, where she fully recovered. We searched the literature for adult cases of acute cerebellitis. Including our patient, we identified 35 patients with a median age of 36 years. The etiology was unknown in 34% of cases. The most common clinical presentation consisted of headache, nausea/vomiting and ataxia. Six patients presented with only headache and nausea and subsequently returned with cerebellar signs. In 9 cases, the cerebellitis was complicated by hydrocephalus. Half of the patients ended up with neurological sequelae, while follow-up MRI was abnormal in 71%.

Conclusion

Acute cerebellitis in adults is a rare disorder which mainly presents with headache, nausea/vomiting and ataxia. To diagnose cerebellitis, imaging of the brain (preferably MRI) is required and CSF examination may be necessary to narrow the differential diagnosis. The treatment depends on the widely diverse etiology, and treatment with steroids is recommended in the case of cerebellar oedema and hydrocephalus. Neurosurgical intervention may be necessary to prevent brain herniation.

Electronic supplementary material

The online version of this article (10.1186/s13104-017-2935-8) contains supplementary material, which is available to authorized users.

The Complex Diagnostic Challenge in Children With Non-Central Nervous System Cancer and Cerebellar Mutism

Multiple etiologies should be considered in the differential diagnosis of immunocompromised patients with non-central nervous system cancer and viral infections who develop mutism. Acute cerebellitis, caused by infections or by neurotoxicity resulting from chemotherapy; paraneoplastic cerebellar degeneration; atypical posterior reversible encephalopathy syndrome; and acute disseminated encephalomyelitis may all cause mutism in such patients. This condition warrants prompt recognition and may require treatment with immunotherapy, as it may be an immune-mediated process. We present 2 patients with leukemia and viral illness who developed cerebellar mutism in the setting of acute cerebellitis and responded to immunotherapy, suggesting that the condition involved a parainfectious immune-mediated response.

Acute cerebellitis in children: an eleven year retrospective multicentric study in Italy

Background

Acute cerebellitis (AC) and acute cerebellar ataxia (ACA) are the principal causes of acute cerebellar dysfunction in childhood. Nevertheless. there is no accepted consensus regarding the best management of children with AC/ACA: the aim of the study is both to assess clinical, neuroimaging and electrophysiologic features of children with AC/ACA and to evaluate the correlation between clinical parameters, therapy and outcome.

Methods

A multicentric retrospective study was conducted on children ≤ 18 years old admitted to 12 Italian paediatric hospitals for AC/ACA from 01/01/2003 to 31/12/2013. A score based on both cerebellar and extracerebellar signs/symptoms was computed for each patient. One point was given for each sign/symptom reported. Severity was divided in three classes: low, moderate, severe.

Results

A total of 124 children were included in the study. Of these, 118 children received a final diagnosis of ACA and 6 of AC. The most characteristic finding of AC/ACA was a broad-based gait disturbance. Other common symptoms included balance disturbances, slurred speech, vomiting, headache and fever. Neurological sequelae were reported in 6 cases (5%) There was no correlation among symptoms, cerebrospinal fluid findings, clinical outcome. There was no correlation between clinical manifestations and clinical score on admission and length of hospital stay, sex, age and EEG findings with sequelae (P > 0.05).

Children with pathological magnetic resonance imaging (MRI) or computed tomography (CT) had a higher probability of having clinical sequelae.

Treatment was decided independently case by case. Patients with a higher clinical score on admission had a higher probability of receiving intravenous steroids.

Conclusions

We confirmed the literature data about the benign course of AC/ACA in most cases but we also highlighted a considerable rate of patients with neurological sequelae (5%). Pathological MRI or CT findings at admission correlate to neurological sequelae. These findings suggest the indication to perform an instrumental evaluation in all patients with AC/ACA at admission to identify those at higher risk of neurological outcome. These patients may benefit from a more aggressive therapeutic strategy and should have a closer follow-up. Randomized controlled trials are needed to confirm these observations. The ultimate goal of these studies could be to develop a standardized protocol on AC/ACA. The MRI/CT data, associated with the clinical manifestations, may allow us to define the class risk of patients for a neurological outcome.

Complicated acute cerebellitis with obstructive hydrocephalus and tonsillar herniation in a child

Acute cerebellitis (AC) is a rare inflammatory syndrome presenting as cerebellar dysfunction, seen more frequently in children. AC can have a variable course with features of cerebellar dysfunction, raised intracranial pressure and neurological deficits, and can sometimes even be potentially fatal due to complications such as obstructive hydrocephalus and brainstem compression, warranting surgical intervention. We report a case of a 12-year-old boy who presented with raised intracranial pressure and ataxia. Imaging with CT and MRI showed AC with obstructive hydrocephalus and tonsillar herniation. He was managed with medications for raised intracranial pressure and with ventriculoperitoneal shunt, and he recovered completely over a period of 2 weeks. Imaging has an important role in the diagnosis of AC and in differentiating it from acute cerebellar ataxia, which has a more benign course. It is crucial to diagnose and promptly manage the rarely occurring but life-threatening complications of AC.

Acute cerebellitis in paediatric patients: Our experience

INTRODUCTION

Acute cerebellitis is a rare inflammatory disease with a highly variable clinical course that ranges from benign self-limiting symptoms to a fulminant presentation associated with a high risk of death due to compression of the posterior fossa, acute hydrocephalus, and intracranial hypertension.

METHODS

We reviewed clinical, laboratory, and radiological findings from children diagnosed with acute cerebellitis between May 2007 and November 2016. We analysed treatments and clinical and radiological progression.

RESULTS

Nine children met the diagnostic criteria for cerebellitis. Headache, vomiting, and drowsiness were the most frequent initial symptoms; ataxia, dysarthria, and dysmetria were the most common cerebellar signs. Cerebellitis was diagnosed with magnetic resonance imaging, which revealed cerebellar involvement (unilateral or bilateral); computerised tomography images either were normal or showed indirect signs such as triventricular hydrocephalus due to extrinsic compression of the aqueduct of Sylvius. Corticosteroids were the most commonly used treatment (6 patients). One patient required surgery due to triventricular hydrocephalus. Eight patients recovered completely, whereas the ninth displayed neurological sequelae.

CONCLUSIONS

Cerebellitis is a medical and surgical emergency; diagnosis requires a high level of suspicion and an emergency brain magnetic resonance imaging study. It is a clinical-radiological syndrome characterised by acute or subacute encephalopathy with intracranial hypertension and cerebellar syndrome associated with T2-weighted and FLAIR hyperintensities in the cerebellar cortex (unilaterally or bilaterally) and possible triventricular dilatation. Treatment is based on high-dose corticosteroids and may require external ventricular drain placement and decompressive surgery.

Acute hemicerebellitis in a child: a case report of a rare neuropsychiatric disorder

BACKGROUND

Acute cerebellitis is an inflammatory process commonly involving both cerebellar hemispheres. Bilateral cerebellar hemisphere involvement is the most common finding. Acute hemicerebellitis in childhood is an extremely rare unilateral presentation of cerebellitis mimicking a tumor. Its etiology is unknown, although an inflammatory or post infectious origin is presumed. Its clinical outcome is generally good and a self-limited evolution. Clinical improvement and regression of the pathological findings in serial MRI will help differentiate acute hemicerebellitis from a neoplastic process.

CASE PRESENTATION

We present a case of hemicerebellitis in a 7-year-old girl, presenting with severe headache, projectile vomiting, and mixed neuropsychiatric manifestation. MRI of the brain revealed a unilateral cerebellar involvement.

A Rare Cause of Childhood Cerebellitis-Influenza Infection: A Case Report and Systematic Review of Literature

Acute cerebellitis is a benign neurologic condition generally caused by viral or bacterial infections. Influenza associated cerebellitis is extremely rare; a 6-year-old boy with acute cerebellitis, who presented with fever, vomiting, weakness, febrile seizure, and acute cerebellar features, is discussed in this article.

Acute Ataxia in Childhood: 11-Year Experience at a Major Pediatric Neurology Referral Center

We categorized the causes of acute ataxia in the pediatric population-referred to the Division of Neurology-at a large, urban pediatric medical center. Of the 120 cases identified over the past 11 years, post-infectious cerebellar ataxia was the most commonly diagnosed (59%), followed by drug intoxication, opsoclonus-myoclonus ataxia syndrome, episodic ataxia, acute cerebellitis, cerebellar stroke, ADEM, meningitis, cerebral vein thrombosis, Leigh's disease, Miller-Fisher syndrome, and concussion. Among the patients with post-infectious cerebellar ataxia, 85% were 1-6 years old and all had a history of antecedent viral illness. CSF pleocytosis was present in 40% of patients; all had normal brain MRIs. The majority (91%) recovered within 30 days. We conclude that post-infectious cerebellar ataxia remains the most common cause of acute ataxia in childhood and that it carries a good prognosis. We also differentiate acute post-infectious cerebellar ataxia from other causes with similar presentations.

Acute Cerebellitis in Children: A Many-Faceted Disease

Acute cerebellitis is a rare inflammatory condition. It may have a benign, self-limiting course or present as a fulminant disease resulting in severe cerebellar damage or even sudden death. We present the clinical, laboratory, and radiologic data in 9 children diagnosed with acute cerebellitis, who were identified by database search in our pediatric medical center from January 2000 to November 2014. The main presenting symptom was headache, and the main presenting sign was ataxia. Bilateral diffuse hemispheric involvement was the most common imaging finding at presentation. Mycoplasma pneumoniae was the most common infectious pathogen found. Treatment included steroids in all cases, antibiotics in 4, and intravenous immunoglobulins in 6. Six patients had a full recovery, and 3 had residual neurologic complications. Magnetic resonance imaging (MRI) is the modality of choice for diagnosis. The course of acute cerebellitis varies from a commonly benign and self-limiting disease to an occasionally fulminant disease, resulting in severe cerebellar damage or sudden death.

Pseudotumoral hemicerebellitis as a mimicker of Lhermitte-Duclos disease in children: does neuroimaging help to differentiate them?

The clinical presentation and neuroimaging findings of children with pseudotumoral hemicerebellitis (PTHC) and Lhermitte-Duclos disease (LDD) may be very similar. The differentiation between these entities, however, is important because their management and prognosis are different. We report on three children with PTHC. For all three children, in the acute situation, the differentiation between PTHC and LDD was challenging. A review of the literature shows that a detailed evaluation of conventional and neuroimaging data may help to differentiate between these two entities. A striated folial pattern, brainstem involvement, and prominent veins surrounding the thickened cerebellar foliae on susceptibility weighted imaging favor LDD, while post-contrast enhancement and an increased choline peak on (1)H-Magnetic resonance spectroscopy suggest PTHC.

Consensus Paper: Neuroimmune Mechanisms of Cerebellar Ataxias

In the last few years, a lot of publications suggested that disabling cerebellar ataxias may develop through immune-mediated mechanisms. In this consensus paper, we discuss the clinical features of the main described immune-mediated cerebellar ataxias and address their presumed pathogenesis. Immune-mediated cerebellar ataxias include cerebellar ataxia associated with anti-GAD antibodies, the cerebellar type of Hashimoto's encephalopathy, primary autoimmune cerebellar ataxia, gluten ataxia, Miller Fisher syndrome, ataxia associated with systemic lupus erythematosus, and paraneoplastic cerebellar degeneration. Humoral mechanisms, cell-mediated immunity, inflammation, and vascular injuries contribute to the cerebellar deficits in immune-mediated cerebellar ataxias.

Consensus paper: radiological biomarkers of cerebellar diseases

Hereditary and sporadic cerebellar ataxias represent a vast and still growing group of diseases whose diagnosis and differentiation cannot only rely on clinical evaluation. Brain imaging including magnetic resonance (MR) and nuclear medicine techniques allows for characterization of structural and functional abnormalities underlying symptomatic ataxias. These methods thus constitute a potential source of radiological biomarkers, which could be used to identify these diseases and differentiate subgroups of them, and to assess their severity and their evolution. Such biomarkers mainly comprise qualitative and quantitative data obtained from MR including proton spectroscopy, diffusion imaging, tractography, voxel-based morphometry, functional imaging during task execution or in a resting state, and from SPETC and PET with several radiotracers. In the current article, we aim to illustrate briefly some applications of these neuroimaging tools to evaluation of cerebellar disorders such as inherited cerebellar ataxia, fetal developmental malformations, and immune-mediated cerebellar diseases and of neurodegenerative or early-developing diseases, such as dementia and autism in which cerebellar involvement is an emerging feature. Although these radiological biomarkers appear promising and helpful to better understand ataxia-related anatomical and physiological impairments, to date, very few of them have turned out to be specific for a given ataxia with atrophy of the cerebellar system being the main and the most usual alteration being observed. Consequently, much remains to be done to establish sensitivity, specificity, and reproducibility of available MR and nuclear medicine features as diagnostic, progression and surrogate biomarkers in clinical routine.

Varicella Zoster Virus Cerebellitis Without a Rash in an Immunocompetent 85-Year-Old Patient

BACKGROUND

Reactivation of the varicella zoster virus (VZV) in adults rarely presents with neurological symptoms without a rash. To our knowledge, so far, only 3 additional cases of VZV cerebellitis, which presented without a rash and were proven by cerebrospinal fluid analysis, have been reported in the literature.

CASE REPORT

An immunocompetent 85-year-old patient presented with a new-onset tremor. He had no rash, had a normal brain computed tomography and magnetic resonance imaging, and had minimal cerebrospinal fluid findings. Eventually, he was diagnosed as having varicella zoster virus cerebellitis only on the basis of a virological examination.

CONCLUSIONS

The manifestation of a new-onset tremor and gait ataxia should raise a suspicion of cerebellitis caused by VZV, even in the absence of cutaneous manifestations or typical imaging findings.

Magnetic resonance imaging in viral and prion diseases of the central nervous system

The early detection and specific diagnosis of viral infections of the central nervous system are important because many of these diseases are potentially treatable. However, clinical symptoms and physical examination are often nonspecific, and rapid diagnostic tests are available for some, but not all, viruses. Neuroimaging, in conjunction with clinical history and laboratory tests, plays an important role in narrowing the differential diagnoses. In this article, we review the clinical features, imaging characteristics, diagnosis, and treatment of the more common viral infections and prions that involve the central nervous system.

Isoniazid-induced cerebellitis: a disguised presentation

Cerebellitis is a rarely encountered complication of isoniazid therapy. Its occurrence is usually associated with concomitant renal disease and haemodialysis. Herein, we report the case of a patient with this complication who presented with isolated bilateral symmetrical dentate nucleus T2 hyperintensities on magnetic resonance imaging. Isoniazid neurotoxicity has never been reported to cause bilateral dentate hyperintensities, for which the differentials are few and include metronidazole toxicity.

Acute pseudotumoral hemicerebellitis in a child: a rare and distinct entity?

A pseudotumoral presentation of acute hemicerebellitis is rare in pediatric age. The authors report a new single case study of a 7-year-old child with pseudotumoral unilateral cerebellitis mimicking an intracranial tumor, which clinically presented itself with signs of intracranial hypertension and mild contralateral hemiparesis, completely recovered after anti-inflammatory therapy. Brain magnetic resonance imaging (MRI) was essential for the differential diagnosis between inflammatory and neoplastic processes. The literature highlighting specific clues about pseudotumoral hemicerebellitis as a distinct clinical and radiological entity is reviewed.

Magnetic resonance imaging findings in patients presenting with (sub)acute cerebellar ataxia

INTRODUCTION

Acute or subacute cerebellar inflammation is mainly caused by postinfectious, toxic, neoplastic, vascular, or idiopathic processes and can result in cerebellar ataxia. Previous magnetic resonance (MR) studies in single patients who developed acute or subacute ataxia showed varying imaging features.

METHODS

Eighteen patients presenting with acute and subacute onset of ataxia were included in this study. Cases of chronic-progressive/hereditary and noncerebellar causes (ischemia, multiple sclerosis lesions, metastasis, bleedings) were excluded. MR imaging findings were then matched with the clinical history of the patient.

RESULTS

An underlying etiology for ataxic symptoms were found in 14/18 patients (postinfectious/infectious, paraneoplastic, autoimmune, drug-induced). In two of five patients without MR imaging findings and three of eight patients with minimal imaging features (cerebellar atrophy, slight signal alterations, and small areas of restricted diffusion), adverse clinical outcomes were documented. Of the five patients with prominent MR findings (cerebellar swelling, contrast enhancement, or broad signal abnormalities), two were lost to follow-up and two showed long-term sequelae.

CONCLUSION

No correlation was found between the presence of initial MRI findings in subacute or acute ataxia patients and their long-term clinical outcome. MR imaging was more flagrantly positive in cases due to encephalitis.

Acute hemicerebellitis in a young adult: a case report and literature review

Acute hemicerebellitis, marked by headache with or without cerebellar signs, is a rare clinical entity involving a unilateral cerebellar hemisphere. The pathogenesis of acute hemicerebellitis remains unclear, and the disease rarely occurs in adults. Here, we report an 18-year-old woman who presented with a lack of coordination of the right hand and leg lasting longer than one week, following a pulsatile headache. A neurological examination disclosed ocular dysmetria, right-sided limb ataxia and slight truncal ataxia. Cerebrospinal fluid analysis showed mononuclear pleocytosis. The serology and autoimmune studies were unremarkable. Brain magnetic resonance imaging (MRI) revealed a focal signal change in the right cerebellar hemisphere and vermis. Acute hemicerebellitis was diagnosed, and the patient was treated with intravenous methylprednisolone sodium succinate and acyclovir. Subsequently, the headache resolved, and the cerebellar signs were markedly improved. Twenty days after admission, she became asymptomatic and brain MRI showed resolution of cerebellar hyperintensity on the right side. In conclusion, we identified only 6 additional patients with adult-onset acute hemicerebellitis from previous reports, highlighting the importance of recognizing this rare clinical entity. Its clinical outcome is usually favorable, but in the acute phase, attention should be directed toward clinical symptoms that are suggestive of increased intracranial pressure.

A case of acute cerebellitis with a unique sequential change on magnetic resonance imaging

BACKGROUND

Acute cerebellitis with unilateral onset is rare, and magnetic resonance imaging (MRI) is a useful method for demonstrating cerebellar involvement.

PATIENT

We report a 12-year-old girl with acute cerebellitis with a unique sequential change on her MRI.

RESULTS

The patient's brain MRI first revealed cortical lesions mainly in the right cerebellar hemisphere. These subsequently disappeared, and at the same time, new lesions appeared in the opposite cerebellar hemisphere. All the lesions were confined to gray matter in the cerebellum and were isotense on diffusion-weighted imaging and had high signal intensity on the apparent diffusion coefficient map, consistent with the characteristic of vasogenic edema.

CONCLUSION

The sequential MRI demonstrates conversion of hemicerebellitis to bilateral cerebellitis during subacute phase, and vasogenic edema might be contributing to the pathogenesis of acute cerebellitis in this patient.

Catastrophic Cerebellitis in an adolescent: A Case Report

An adolescent presented with headache and projectile vomiting and showed ataxia, dysarthia and nystagmus with normal cognition. A diagnosis of acute cerebellitis was made on the basis of computed tomography and magnetic resonance imaging findings. He developed seizures and had a rapid downhill course with death at 48 hours after admission. Clinically, patients of acute cerebellitis present with fever, nausea, headache and altered sensorium with cerebellar symptoms. Inflammation of the cerebellum compresses the brain stem and induces mental alterations. It is a rare pathology developing due to an infectitious cause, post-infectitious or post vaccination etiology. Many times it is not possible to identify the causative agent. Cerebellitis can be mild where recovery occurs in few weeks and no abnormalities are seen on diagnostic imaging studies. On the other end, severe cases have focal neurological deficits, altered consciousness, raised intracranial pressure and abnormal neuroimaging. Treatment should be tailored to individual needs according to presentation, severity, and etiology. We discuss clinical features, diagnosis and management of acute cerebellitis which is an important cause of acute cerebellar functional disorder in childhood.

Acute cerebellitis in varicella: a ten year case series and systematic review of the literature

Background

Acute cerebellitis (AC) is the most common neurological complication of varicella. Nevertheless, it has been scarcely studied. The objective of this study were to asses the occurrence of AC among children hospitalized for varicella and to analyze its specific clinical picture and outcome.

Methods

We retrospectively reviewed the medical records of children admitted to the hospital for varicella between 1^st October 2003 and 1^st June 2013 and we compared our results with literature. Children were all unvaccinated for varicella.

Results

In our case series, AC was found out in 48 out of 457 patients (10.5%). The highest frequency of AC was observed in children from 1 to 5 years of age (60.9%). The most characteristic symptom of AC was a broad-based gait disturbance that progressed gradually over the course of a few days (95.8%). Other common symptoms included slurred speech (37.5%), vomiting (31.25%), headache (29.16%), dysmetry (25%) and tremor (22.91%). After a long hospitalization (median of 11 days), all but one children were dismissed without invalidating sequelae.

Conclusions

Data from this study may help to better address the problem of varicella cerebellar complications in hospitalized children and to monitor changes over time caused by an increase in vaccination coverage.

Subclinical immune reactions to viral infections may correlate with child and adolescent diagnosis of attention-deficit/hyperactivity disorder: a preliminary study from Turkey

BACKGROUND

Attention-Deficit/Hyperactivity Disorder (ADHD) is one of the most common neuro-developmental disorders of childhood and adolescence. Studies focusing on the relationship of infectious agents and ADHD are scarce. It is also known that cerebellar injury may lead to hyperactive behavior. This study aimed to evaluate the relationship between viral agents of cerebellitis and the diagnosis of ADHD.

METHODS

The study group was formed of 60 consecutive ADHD patients and 30 healthy children. IgG levels for VZV; HSV-1, CMV, Measles, Mumps, Rubella and EBV were evaluated.

RESULTS

Males were significantly higher among patients with ADHD (65% vs. 40%, p=0.025). Patients with ADHD displayed significantly higher positivity for measles IgG (80% vs. 60%, p=0.044). When patients with ADHD were classified according to their pubertal status, adolescents with ADHD displayed higher positivity for mumps (100% vs. 74.4%, p=0.043). Most of the patients were diagnosed with ADHD-Combined or Hyperactive/Impulsive Subtypes (56.6%) while 43.3% were diagnosed with ADHD-predominantly inattentive type. When patients with subtypes of ADHD were compared in terms of seropositivity, it was found that patients with ADHD-Combined/ Hyperactive-Impulsive subtypes had significantly elevated reactions for Rubella (100% vs. 88.5%, p=0.044).

CONCLUSION

Although limited to a single center and may be prone to sampling biases, our results may support the notion that immune reactions may be related with ADHD among children and adolescents. Further, prospective studies from multiple centers are needed to support our findings and establish causality.

Hemicerebellitis: Report of three paediatric cases and review of the literature

Acute inflammation of a single cerebellar hemisphere (hemicerebellitis) is a rare disorder of unknown origin. The clinical presentation is mainly characterized by headache, ataxia, dysmetria, and vomiting. In addition, some children may develop severe intracranial hypertension. The neuroimaging of hemicerebellitis raises a challenging differential diagnosis, particularly with posterior fossa tumours. Although there is no standard treatment for hemicerebellitis, its outcome is usually favourable. However, ipsilateral hemicerebellar atrophy develops in up to half of cases, and a minority of children may show persisting fine motor and/or neurocognitive sequelae. In this article, we contribute with three new reports and review a total of 35 cases of hemicerebellitis.

An unusual cause of altered mental status in elderly-acute cerebellitis: a case report and review

Acute cerebellitis is a rare diagnosis found mostly in the pediatric population. The etiology, in most instances, is unknown. We describe the case of a 61-year-old woman who presented with acute mental status changes, signs of cerebellar dysfunction, and MRI findings of acute cerebellitis. A brief review of the existing literature and comparison of our case with previous reports are also presented.

Magnetic resonance imaging biomarkers in patients with progressive ataxia: current status and future direction

A diagnostic challenge commonly encountered in neurology is that of an adult patient presenting with ataxia. The differential is vast and clinical assessment alone may not be sufficient due to considerable overlap between different causes of ataxia. Magnetic resonance (MR)-based biomarkers such as voxel-based morphometry, MR spectroscopy, diffusion-weighted and diffusion-tensor imaging and functional MR imaging are gaining great attention for their potential as indicators of disease. A number of studies have reported correlation with clinical severity and underlying pathophysiology, and in some cases, MR imaging has been shown to allow differentiation of conditions causing ataxia. However, despite recent advances, their sensitivity and specificity vary. In addition, questions remain over their validity and reproducibility, especially when applied in routine clinical practice. This article extensively reviews the current literature regarding MR-based biomarkers for the patient with predominantly adult-onset ataxia. Imaging features characteristic of a particular ataxia are provided and features differentiating ataxia groups and subgroups are discussed. Finally, discussion will turn to the feasibility of applying these biomarkers in routine clinical practice.