Malignant cerebellar edema in three-year-old girl following accidental opioid ingestion and fentanyl administration

A three-year-old girl was found altered with an unknown timeline. Gas chromatography mass spectrometry was positive for hydromorphone, dihydrocodeine, and hydrocodone. Initial computed tomography and magnetic resonance imaging suggested a malignant cerebellar edema not confined to a vascular distribution. She received fentanyl boluses on hospital days 0 and 1 before receiving a continuous infusion on day 1. On day 3, she had an episode of acute hypertension and bradycardia. Emergent computed tomography showed an evolving hydrocephalus and similar diffuse edema throughout both cerebellar hemispheres. External ventricular drain was placed to relieve the increased intracranial pressure. Following drain placement and fentanyl discontinuation, the patient recovered, though not without fine- and gross-motor deficits at the four-month follow-up. Our case adds to a handful of case reports of opioid toxicity in pediatric patients that present as toxic leukoencephalopathy. Though the mechanism is poorly understood, it has been suggested to be a consequence of the neurotoxic effects of the drug, which has particular affinity for µ opioid receptors-the primary opioid receptor found in the cerebellum. Clinicians would do well to recognize that this syndrome is primarily caused by direct toxicity rather than ischemia. This case adds insight by suggesting that lipophilic opioid analgesics may worsen this neurotoxicity. When intervening with mechanical ventilation, clinicians should consider avoiding lipophilic opioid drugs for analgesia until the pathogenesis of cerebellar edema is better understood.

The Impact of Persistent Leukoencephalopathy on Brain White Matter Microstructure in Long-Term Survivors of Acute Lymphoblastic Leukemia Treated with Chemotherapy Only

BACKGROUND AND PURPOSE

Survivors of acute lymphoblastic leukemia are at risk for neurocognitive deficits and leukoencephalopathy. We performed a longitudinal assessment of leukoencephalopathy and its associations with long-term brain microstructural white matter integrity and neurocognitive outcomes in survivors of childhood acute lymphoblastic leukemia treated on a modern chemotherapy-only protocol.

MATERIALS AND METHODS

One hundred seventy-three survivors of acute lymphoblastic leukemia (49% female), treated on a chemotherapy-only protocol, underwent brain MR imaging during active therapy and repeat imaging and neurocognitive testing at follow-up (median, 13.5 years of age; interquartile range, 10.7-17.6 years; median time since diagnosis, 7.5 years; interquartile range, 6.3-9.1 years). Persistence of leukoencephalopathy was examined in relation to demographic and treatment data and to brain DTI in major fiber tracts and neurocognitive testing at follow-up.

RESULTS

Leukoencephalopathy was found in 52 of 173 long-term survivors (30.0%) and persisted in 41 of 52 (78.8%) who developed it during therapy. DTI parameters were associated with leukoencephalopathy in multiple brain regions, including the corona radiata (fractional anisotropy, P = .001; mean diffusivity, P < .001), superior longitudinal fasciculi (fractional anisotropy, P = .02; mean diffusivity, P < .001), and superior fronto-occipital fasciculi (fractional anisotropy, P = .006; mean diffusivity, P < .001). Mean diffusivity was associated with neurocognitive impairment including in the genu of the corpus callosum (P = .04), corona radiata (P = .02), and superior fronto-occipital fasciculi (P = .02).

CONCLUSIONS

Leukoencephalopathy during active therapy and neurocognitive impairment at long-term follow-up are associated with microstructural white matter integrity. DTI may be more sensitive than standard MR imaging for detection of clinically consequential white matter abnormalities in childhood acute lymphoblastic leukemia survivors treated with chemotherapy and in children undergoing treatment.

Acute and sub-acute neurological toxicity in children treated for acute lymphoblastic leukemia

Eighty percent of children with acute lymphoblastic leukemia (ALL) survive with current treatments. Neurotoxicity is an infrequent adverse event. We describe clinical presentations of neurological toxicity, phases of treatment when these adverse events were more frequent and patients ́ outcome. From January-1995 to December-2015, 1379 ALL cases were admitted. Neurotoxicity was diagnosed in 49 patients (3.6%) and classified according to neurological syndromes. Medical records, laboratory-tests and images were reviewed. The diagnosed syndromes were: a) Methotrexate-leukoencephalopathy (MLE) (35.4%); b) Cerebral-venous-sinus thrombosis following L-Asparaginase administration (26.5%); c) Vincristine-induced-vocal-cord paralysis (VVCP) (14.2%); d) Stroke-associated vasospasm (14%), after high-dose methotrexate e) Severe polyneuropathy (6.1%); f) Methotrexate myelopathy (2%); and g) Pseudotumor-cerebri (2%) associated with corticosteroid therapy. Neurotoxicity was diagnosed during induction in 55% of cases. We conclude that MLE was the most frequent syndrome. VVCP was observed in infants and Down patients. Seizure was the most common symptom and toxicity occurred mainly during induction phase.

'Khatatonia' - cathinone-induced hypertensive encephalopathy

Khat consumption is an under-recognised cause of hypertensive encephalopathy and intraparenchymal brain haemorrhage. We report the radiological findings of extensive periventricular, subcortical and brain stem white matter pathology of a patient who had consumed excessive amounts of Khat. The Khat plant contains cathinone, an amphetamine-like alkaloid which has been associated with chronic hypertensive end-organ damage, but is seldom considered a cause of cerebrovascular events in northern Europe.

Rat white matter injury model induced by endothelin-1 injection: technical modification and pathological evaluation

White matter injury is an important cause of functional disability of the brain. We comprehensively analyzed a modified endothelin-1 (ET‑1) injection-induced white matter injury model in the rat which is very valuable for investigating the underlying mechanisms of subcortical ischemic stroke. ET-1 was stereotactically injected into the internal capsule of the rat. To avoid complications with leakage of ET-1 into the lateral ventricle, the safest trajectory angle to the target was established. Rats with white matter injury were extensively evaluated for structural changes and functional sequelae, using motor function tests, magnetic resonance (MR) imaging, histopathology evolution, volume estimation of the lesion, and neuroanatomical identification of affected neurons using the retrograde tracer hydroxystilbamidine. Optimization of the trajectory of the ET-1 injection needle provided excellent survival rate. MR imaging visualized the white matter injury 2 days after surgery. Motor function deficit appeared temporarily after the operation. Histological studies confirmed damage of axons and myelin sheaths followed by inflammatory reaction and gliosis similar to lacunar infarction, with lesion volume of less than 1% of the whole brain. Hydroxystilbamidine injected into the lesion revealed wide spatial distribution of the affected neuronal population. Compared with prior ET-1 injection models, this method induced standardized amount of white matter damage and temporary motor function deficit in a reproducible and safe manner. The present model is valuable for studying the pathophysiology of not only ischemia, but a broader set of white matter damage conditions in the lissencephalic brain.

[Delayed posthypoxic leucoencephalopathy after suicide attempt with opioids]

Delayed posthypoxic leucoencephalopathy (DPHL) is a rare condition with manifestation of neurological and neuropsychological symptoms, following an acute hypoxic condition with an intermittent recovery period of four weeks. MRI findings show symmetric subcortical white matter lesions. We present a patient admitted with symptoms and brain MRI-scan consistent with DPHL. Four weeks prior the patient had tried to commit suicide with opioids. DPHL should be considered in patients with subacute onset of neurological and neuropsychological symptoms after an acute hypoxic condition of the brain.

Capecitabine-induced leukoencephalopathy involving the bilateral corticospinal tracts

An 80 year old lady with a history of metastatic sigmoid carcinoma presented with expressive dysphasia and unsteady gait 4 days after commencement of adjuvant capecitabine chemotherapy. MRI demonstrated restricted diffusion and T2/FLAIR hyperintensity involving the course of the bilateral corticospinal tracts, the corpus callosum and the middle cerebellar peduncles. Discontinuation of chemotherapy lead to symptom resolution in 2 days; repeat MRI at 2 months demonstrated reversal of the diffusion changes and improvement of the previous T2W/FLAIR hyperintensity. This report describes the first case of capecitabine induced leukoencephalopathy causing restricted diffusion along the corticospinal tracts, which should be differentiated from other entities that involve the corticospinal tracts (i.e. amyotrophic lateral sclerosis (ALS), primary lateral sclerosis (PLS), hypoglycemic coma, etc.).

[Fatal toxic leukoencephalopathy associated with consumption of pasta base of cocaine: Report of three cases]

The prevalence of drug-associated toxic encephalopathy is unknown, but it is an uncommon condition. Toxic leukoencephalopathy was described associated with heroin consumption, it has been less commonly described with the use of cocaine and there are no reports of its association with consumption pasta base of cocaine (PBC). We report two females aged 31 years and a male aged 19 years, consumers of PBC who developed a fatal toxic leukoencephalopathy. They initiated their disease with severe and persistent headache, sequential focal neurologic deficits and a progressive impairment of consciousness that culminated with their death. Laboratory parameters such as blood count, cerebrospinal fluid analyses or infectious biological indices were normal. MRI showed multifocal lesions in brain white matter of both hemispheres confirming the leukoencephalopathy. There was no response to the use of methylprednisolone.

Tobacco Smoke-Induced Brain White Matter Myelin Dysfunction: Potential Co-Factor Role of Smoking in Neurodegeneration

BACKGROUND

Meta-analysis studies showed that smokers have increased risk for developing Alzheimer's disease (AD) compared with non-smokers, and neuroimaging studies revealed that smoking damages white matter structural integrity.

OBJECTIVE

The present study characterizes the effects of side-stream (second hand) cigarette smoke (CS) exposures on the expression of genes that regulate oligodendrocyte myelin-synthesis, maturation, and maintenance and neuroglial functions.

METHODS

Adult male A/J mice were exposed to air (8 weeks; A8), CS (4 or 8 weeks; CS4, CS8), or CS8 followed by 2 weeks recovery (CS8 + R). The frontal lobes were used for histology and qRT-PCR analysis.

RESULTS

Luxol fast blue, Hematoxylin and Eosin stained histological sections revealed CS-associated reductions in myelin staining intensity and narrowing of the corpus callosum. CS exposures broadly decreased mRNA levels of immature and mature oligodendrocyte myelin-associated, neuroglial, and oligodendrocyte-related transcription factors. These effects were more prominent in the CS8 compared with CS4 group, suggesting that molecular abnormalities linked to white matter atrophy and myelin loss worsen with duration of CS exposure. Recovery normalized or upregulated less than 25% of the suppressed genes; in most cases, inhibition of gene expression was either sustained or exacerbated.

CONCLUSION

CS exposures broadly inhibit expression of genes needed for myelin synthesis and maintenance. These adverse effects often were not reversed by short-term CS withdrawal. The results support the hypothesis that smoking contributes to white matter degeneration, and therefore could be a key risk factor for a number of neurodegenerative diseases, including AD.

Intravenous Heroin-Associated Delayed Spongiform Leukoencephalopathy: Case Report and Reviews of the Literature

Heroin-associated spongiform leukoencephalopathy is a rare, and sometimes fatal, condition usually caused by vapor inhalation of heroin. The authors report a 41-year-old man who was diagnosed with delayed spongiform leukoencephalopathy three weeks after injecting heroin intravenously. He had been admitted to another hospital due to acute heroin overdose, which had occurred four hours after intravenous injection of an unknown amount of heroin. His clinical condition showed progressive improvement and he was discharged 12 days after admission. Three weeks after this episode, his cognitive functioning declined. Akinetic mutism, spasticity and hyperreflexia of all extremities were observed. Electroencephalography (EEG) and imaging of the brain showed typical characteristics of spongiform leukoencephalopathy. The three and six-month follow-up of the patient showed clinical improvement and this was corroborated through EEG measures and brain imaging. The discussion summarizes eight previously reported cases of intravenous heroin associated spongiform leukoencephalopathy and compares them to the authors'case.

[Disease modifying therapies in multiple sclerosis]

The purpose of this section is to introduce the clinical utility of several disease-modifying agents including natalizumab and immunosuppressive treatments that are currently available in Japan, and glatiramer acetate that will be probably available in Japan within a few years. Immunosuppressive therapy has been used to treat multiple sclerosis(MS) for over 30 years based on the hypothesis that MS is a T cell-mediated autoimmune disease. The most commonly used immunosuppressive agents in MS are azathioprine, cyclophosphamide, methotrexate, and mitoxantrone. Like the interferons and glatiramer acetate, immunosuppressive drugs are most efficacious in stages of MS that have an inflammatory component as evidenced by relapses and/or gadolinium-enhancing lesions on MRI or in patients in earlier stages of disease where inflammation predominates over degenerative processes in the CNS. There is no evidence of efficacy in primary progressive MS or later stages of secondary progressive MS. It is appropriate to consider glatiramer acetate for treatment in any patient who has relapsing remitting MS (RRMS), and glatiramer acetate may be helpful in patients with progressive disease. Because of the possibility that natalizumab therapy may be responsible for the increased risk of primary progressive leukoencephalopathy (PML), it is recommended that natalizumab be reserved for use in selected patients with relapsing remitting disease who have failed other therapies either through continued disease activity or medication intolerance, or who have a particularly aggressive initial disease course.

[Early diagnosis of capecitabine-induced acute leukoencephalopathy by using diffusion-weighted MRI]

A 63-year-old woman with colon cancer who was treated with capecitabine as adjuvant chemotherapy presented with vertigo on day 5, and dysarthria and dysphagia on day 7 of the treatment. Diffusion-weighted magnetic resonance imaging of the brain revealed high signal intensity in the corpus callosum and corona radiata. The patient was diagnosed with acute leukoencephalopathy, and the capecitabine treatment was discontinued. Her symptoms recovered immediately. On the basis of these findings, it can be concluded that diffusion-weighted imaging is useful for the early detection and diagnosis of acute leukoencephalopathy.

Delayed leukoencephalopathy after acute carbon monoxide intoxication

Delayed leukoencephalopathy is an uncommon complication of hypoxic-ischemic events of different etiologies, including carbon monoxide intoxication. We present a case of a 40-year-old male patient who was admitted with rapidly progressive neurocognitive and behavioral deficits. There was a history of accidental carbon monoxide intoxication one month before, presenting with loss of consciousness and short hospitalization, followed by a complete clinical recovery. The imaging studies in the delayed phase depicted confluent, symmetric supra-tentorial white matter lesions in keeping with diffuse demyelinization. Restricted diffusion and metabolite abnormalities in magnetic resonance proton spectroscopy were also seen. The diagnosis of CO-mediated delayed post-hypoxic leukoencephalopathy was assumed after exclusion of other mimickers. Hyperbaric oxygen therapy was tentatively performed and the patient had a favorable clinical and radiological evolution.

[Bevacizumab-induced reversible posterior leukoencephalopathy syndrome in a patient with metastatic colorectal cancer]

We report a rare case of a 67-year-old woman with metastatic colorectal cancer whose bevacizumab (B-mab) +m-FOLFOX6 treatment was complicated by reversible posterior leukoencephalopathy syndrome (RPLS). In July 2011, she underwent a right hemicolectomy for cecal carcinoma with peritoneal dissemination; therefore, m-FOLFOX6 was started in September 2011. In November 2011, she was hospitalized to add B-mab to the existing regimen. Subsequently, she developed hypertension on day 4 after the first B-mab infusion, followed by headache, convulsions, and disturbance of consciousness on day 5. T2-weighted and fluid-attenuated inversion recovery (FLAIR) non-enhanced magnetic resonance imaging of the brain revealed bilateral high signal intensities in the posterior lobes. She was diagnosed with RPLS and referred to our department where she was treated with antihypertensives and anticonvulsives. Her symptoms entirely resolved over 12 days. Medical oncologists should be aware that multidrug chemotherapies with B-mab may increase the risk of fatal neurological complications such as RPLS.