Systematic approach to diagnosing suspected Creutzfeldt-Jakob disease.

Evaluation of rapidly progressive dementia (RPD) is usually challenging. In most cases, patients progress to dementia in weeks to months, and the differential diagnosis is broad. In this case, a woman in her 60s presented with a 1-month history of episodic vertigo, cognitive decline, ataxia and myoclonus. Cerebrospinal fluid total tau was markedly elevated, which was helpful in establishing the diagnosis and discussing prognosis/end-of-life measures with the patient's family. This case summarises a stepwise diagnostic approach for patients with RPD and highlights recent literature on biomarkers of Creutzfeldt-Jakob disease and autoimmune encephalitis.

Bickerstaff brainstem encephalitis: clinical, neurophysiological, laboratory and postmortem findings of a case presenting as encephalomyelitis.

Our patient was admitted to hospital with a 1-week history of an upper respiratory tract infection and a rapidly progressive encephalopathy dominated by brainstem features and widespread areflexia. Her antiganglioside antibodies and electroencephalography were consistent with Bickerstaff brainstem encephalitis (BBE), and her postmortem examination revealed a predominantly florid brainstem encephalitis and myelitis. Her sputum and throat swabs isolated Haemophilus influenzae and Fusobacterium, respectively, the former being the most probable trigger of BBE. Our patient's death, despite the otherwise good prognosis of the disorder, may reflect the severity of the pathological changes at postmortem or the association of comorbid disorders such as sepsis-associated encephalopathy. Her poor outcome may also be an indication to treat rapidly progressive cases of BBE with more than one immune modulating drug.

Spinal leptomeningeal hemangioblastomatosis occurring without craniospinal surgery in von Hippel-Lindau disease.

Hemangioblastomatosis represents an unusual and malignant leptomeningeal dissemination of hemangioblastoma (HB). It has been reported in patients with sporadic HB or von Hippel-Lindau (VHL) disease. Hemangioblastomatosis had been reported following resection of a primary HB lesion in all cases except one patient with a sporadic HB. We present a patient with VHL with several HBs at the brainstem, cerebellum, pituitary stalk and retina who developed spinal hemangioblastomatosis without previous craniospinal surgery. A whole spine MRI showed the spinal dissemination from the primary lesions. The patient received craniospinal radiotherapy due to the extensive spinal leptomeningeal dissemination and multiple HBs. MRI performed 12 months after the radiotherapy showed stability of the lesions.

Tumour-like presentation of atypical posterior reversible encephalopathy syndrome with prominent brainstem involvement.

Typical posterior reversible encephalopathy syndrome (PRES) is a clinical-neuroradiological entity characterised by bilateral white matter oedema, which is usually symmetrical and totally reversible in 2-3 weeks. A 46-year-old man presented with a persistent headache and visual blurring in the right eye. On admission, the clinical examination revealed minimal unsteadiness of gait and elevated blood pressure. A brain MRI showed a hyperintense signal on T2-weighted sequences in the whole brainstem, extended to the spinal cord (C2-C6), the left insula and the right cerebellum. When his blood pressure was controlled, his symptoms gradually improved. The follow-up MRI scan at 3 weeks revealed a dramatic regression of the hyperintense lesions on T2-weighted sequences. The differential diagnosis of PRES is very wide, especially in the case of conspicuous brainstem involvement. Treatable causes of white matter oedema should be always kept in mind to avoid misdiagnosis and prevent complications, such as intracranial haemorrhage.

Intravenous immunoglobulins in an adult case of post-EBV cerebellitis.

Post-Epstein-Barr virus (EBV) cerebellitis is very rare complication of infectious mononucleosis and only a few adult cases are reported in literature. We present a 23-year-old patient who was admitted to the neurology service with worsening ataxia, nystagmus and dysarthria, 1 week after infectious mononucleosis. Imaging and cerebrospinal fluid studies were normal, serum studies revealed acute transaminitis and positive EBV viral capsid IgM and IgG. The patient underwent a 5-day course of intravenous immunoglobulins with rapid resolution of all his symptoms and was safely discharged home. The pathophysiology of post-EBV cerebellitis involves autoreactive antibodies, rather than a direct viral insult. Antineuronal antibodies might be the result of a mimicry between EBV proteins and neuronal antigens or they can be secreted by the EBV-transformed lymphocytes themselves. Many reports stress the benign, self-limiting nature of this syndrome; however, immunotherapy might de facto decrease the severity and duration of illness.

Hyponatraemia presenting as reversible cerebellar ataxia in Addison's disease.

Addison's disease is a common endocrinopathy often diagnosed in patients presenting with hyponatraemia. Cerebellar ataxia as a presentation of hyponatraemia is extremely rare. A 42-year-old man presented with vomiting, fever, ataxic gait and scanning type of dysarthria. Clinical examination revealed signs suggestive of isolated cerebellar involvement. Patient was found to have severe hyponatraemia and serum cortisol was found to be extremely low while MRI brain was found to be normal. Corticosteroid therapy was initiated and cerebellar ataxia was resolved following normalisation of sodium levels.

Pure sensory stroke due to brainstem lesion.

A 40-year-old male patient presented to the emergency department with acute onset right-sided upper and lower extremity numbness/tingling over the past day. Prior to the paraesthesia onset, the patient experienced transient mild ataxia and left ocular pain with complete resolution at the time of presentation. Neurological exam revealed isolated right-sided sensory changes from his hand-to-elbow as well as foot-to-knee. No other focal neurological deficits were noted. MRI brain revealed a small left posterior infarct at the junction between the pons and midbrain. Dual-antiplatelet therapy was initiated and the patient experienced minimal paraesthesia improvement proximally over his 5-day hospital course. This case report highlights an acute brainstem stroke presenting with predominant hemisensory symptoms. Presentations of brainstem lesions can range from subtle, non-specific features to profound deficits. This case serves to emphasise the importance of performing a thorough clinical exam while maintaining a high index of suspicion for brainstem lesions.

Neurosyphilis presenting as pure cerebellar ataxia: an atypical manifestation.

Neurosyphilis has become an uncommon diagnosis in the current era. Neurological manifestations of syphilis usually lie within the spectrum of meningovascular syphilis, tabes dorsalis or general paresis of the insane. Although sensory ataxia may occur as part of spinal cord involvement, cerebellar ataxia has been rarely described as a manifestation of neurosyphilis. In this report, we describe a rare case neurosyphilis presenting in the form of a pure pancerebellar syndrome of subacute progression.

Delayed mid-basilar artery stenosis following paediatric acute mechanical thrombectomy: a rare complication from a rare case.

There is limited literature on the use of mechanical thrombectomy with stent-retrievers in paediatric stroke, especially in the posterior circulation. We report a paediatric case of acute basilar artery occlusion successfully treated by mechanical thrombectomy using stent-retriever but complicated by delayed basilar artery stenosis. This case emphasises prudent selection of thrombectomy device and meticulous long-term follow-up when employed in paediatric stroke.

Garbled speech: a rare presentation of metronidazole-induced neurotoxicity.

Neurotoxicity is a rare but significant side effect of metronidazole. We present, here, a case of a 34-year-old man, presenting with garbled speech and word finding difficulty. He was taking metronidazole for the last 3 months for stage 4 decubitus ulcers. MRI of the brain showed abnormal signal intensities in the splenium of the corpus callosum and dentate nuclei of the cerebellum. The diagnosis of metronidazole-induced neurotoxicity was made based on MRI findings. The antibiotic was stopped leading to resolution of abnormal MRI findings. We advocate that metronidazole can be associated with severe neurotoxicity, but its prompt cessation leads to better outcome and prognosis.

Neuro-Behçet's masquerading as progressive bulbar palsy: a case report and literature review.

In patients with progressive bulbar palsy without an obvious cause, there should be a high index of suspicion for the potential diagnosis of Neuro-Behçet's Disease, even in the absence of the acute classical peripheral manifestations of Bechet's Disease, with emphasis in prompt diagnosis using 'The International Criteria for Behçet's Disease' and rapid, effective treatment in order to improve outcome.

Bilateral paramedian pontine infarcts: a rare cause of bilateral horizontal gaze palsy.

A 73-year-old man presented to accident and emergency with headache and diplopia. Examination of the eye movements revealed a bilateral complete horizontal gaze palsy. On admission, a CT scan of the brain was performed, which was unremarkable. An MRI of the brain was then performed, which confirmed tiny acute infarcts involving the pons and the right cerebellum. This man was promptly treated with aspirin 300 mg one time per day, as per the stroke pathway. Further diagnostic workup later revealed atrial flutter. This man was therefore commenced on apixaban. The differential diagnoses for bilateral gaze palsy include the following: multiple sclerosis, infarction, haemorrhage and space occupying lesion. Bilateral gaze palsy is often associated with other neurological symptoms.

Case of non-alcoholic Wernicke's encephalopathy.

A 61-year-old obese man presented with 8-week history of nausea and occasional vomiting. He reported poor appetite and unintentional weight loss of more than 20 kg of his body mass. A week after admission, he developed double vision and unsteady gait. Neurological examination revealed isolated sixth cranial nerve palsy on the left side with horizontal nystagmus that progressed to bilateral lateral gaze palsy with normal vertical gaze. Brain MR revealed T2/fluid attenuation inversion recovery (FLAIR) high signal in mammillary bodies, tectum of the midbrain and the periaqueductal grey matter. He was diagnosed with Wernicke's encephalopathy (WE). WE is a medical emergency that carries high mortality yet can be often under-diagnosed in the non-alcoholic patient. Varied presentation and absence of alcohol dependence lowers the degree of suspicion and this was true in this case. The patient was given intravenous thiamine and made a rapid and dramatic recovery.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) in limited cutaneous sclerosis: a rare disease combination.

A 26-year-old patient of limited cutaneous sclerosis presented to us with insidious-onset posterior fossa symptoms of headache, vomiting, vertigo and gait imbalance, progressing over a period of 3 weeks. A diagnosis of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids was made by combining the clinical features with radiological evidence showing punctate infiltration of the pons, brainstem and cerebellum. Relevant differentials in the form of neurosarcoid, infections, central nervous system (CNS) lymphoma and Neuro-Behcet's disease were ruled out by history and investigations. The patient responded dramatically to steroid therapy, and had no neurological deficits after 18 months of follow-up. This case highlights the rare association of a not-so-common immunological disease with a rare neurological disease.

Hemidysgeusia, phantosmia and respiratory arrest: a case of CLIPPERS.

A 56-year-old man presented with a relapse of likely chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) after a reduction of steroid dose. MRI demonstrated new perivascular FLuid-Attenuated Inversion Recovery (FLAIR) signal hyperintensity involving the dorsal pontomedullary junction and progressing inferiorly into the dorsal medulla oblongata. His admission to hospital was complicated by a respiratory arrest.

Brainstem encephalitis caused by Coxsackie A16 virus in a rituximab-immunosuppressed patient.

Rituximab and other B cell depleting agents are increasingly used for haematological, immunological and neurological diseases. In a small minority, immunosuppression leads to increased virulence of normally mild infections. Brainstem encephalitis has been described occurring after infection from enteroviruses, more commonly in the paediatric population, but also in immunosuppressed adults. In this paper, we describe an enteroviral brainstem encephalitis in a rituximab-immunosuppressed patient. The enterovirus identified was Coxsackie A16, which has never yet been reported to cause brainstem encephalitis in an adult.

Rare presentation of AICA syndrome.

We report a rare presentation of an anterior inferior cerebellar artery (AICA) infarct in a 74-year-old woman with acute-onset nausea, vomiting, vertigo and gait instability long before the full onset of symptoms and a negative MRI on admission. Over the next several days the patient developed left facial weakness, numbness, hypoacusis, and limb and gait ataxia, and was found to have acute infarcts of the left pons and cerebellar peduncle consistent with an AICA syndrome. We discuss this rare stepwise presentation in AICA syndrome and possible underlying pathophysiology. Such patients at risk for cerebrovascular disease should undergo a careful history, exam and follow-up, even with negative MRI findings, as their symptoms may precede a serious vascular event.