MR findings in globoid cell leucodystrophy

Newly Diagnosed Hepatic Encephalopathy Presenting as Non-convulsive Status Epilepticus: A Case Report and Literature Review

BACKGROUND

Hepatic encephalopathy is characterized by psychiatric and neurological abnormalities, including epileptic seizure and non-convulsive and convulsive status epilepticus. Conventional brain magnetic resonance imaging is useful in supporting diagnosis since it can reveal specific radiological findings. In the literature, there is no description of hepatic encephalopathy onset as non-convulsive status epilepticus; we provide the first report.

CASE SUMMARY

We report a case of a 67-year-old woman, without history of cirrhosis, presenting altered mental state, normal brain computed tomography imaging, and electroencephalography suggestive of epileptic activity. We suspected non-convulsive status epilepticus, and we administered diazepam and levetiracetam with clinical improvement. Thus, we made a diagnosis of non-convulsive status epilepticus. A radiological study with brain magnetic resonance imaging showed bilateral hyperintensity on T1-weighted sequences of globus pallidus and hyperintensity of both corticospinal tracts on T2-weighted fluid-attenuated inversion recovery sequences. Blood tests revealed hyperammonemia, mild abnormality of liver function indices, and chronic Hepatitis B and D virus coinfection. Hepatic elastosonography suggested liver cirrhosis. The patient started antiviral therapy with entecavir and prevention of hepatic encephalopathy with rifaximin and lactulose; she was discharged with a normal mental state.

CONCLUSIONS

Hepatic encephalopathy can present as an initial manifestation with non-convulsive status epilepticus. Electroencephalography is useful for differentiating non-convulsive status epilepticus from an episode of hepatic encephalopathy, and neuroimaging aids the diagnostic process.

Metabolic disorders of the brain: part I

Due to nonspecific clinical presentation, diagnosis of metabolic disorders affecting the brain is very challenging for physicians. It is always the constellation of the clinical examination, biochemical assay and imaging that helps in reaching the diagnosis of metabolic disorders. Diagnosis of these disorders or even limiting the differential diagnosis on imaging may pose a formidable challenge to the radiologist. In these two articles (Metabolic Disorders of the Brain: Parts I and II) we have tried to highlight the important clinical and imaging pearls of the major and more commonly encountered metabolic disorders. In the first article we discuss metabolic disorders related to dysfunction of the cellular organelle namely lysosomal, peroxisomal, and mitochondrial. We have also discussed the relevant genetic abnormalities, biochemical findings and application of newer imaging techniques which may aid in diagnosis of these various disorders.

Magnetic resonance spectroscopy and magnetic resonance imaging findings in Krabbe's disease

Two twins with late infantile globoid cell leukodystrophy of Krabbe's disease were studied with conventional magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy. Brain MRI demonstrated brain atrophy with extensive bilateral symmetric abnormal T2 signal in the posterior periventricular white matter, parietal lobes, corona radiata, centrum semiovale, and splenium of the corpus callosum. Magnetic resonance imaging-guided proton magnetic resonance spectroscopy revealed prominent peaks from choline-containing compounds, total creatine, and inositols. The N-acetylaspartate peak was markedly reduced, and the choline-to-N-acetylaspartate ratio was abnormally high; in one of the twins, lactic acid was also detected. The constellation of magnetic resonance spectroscopy findings is indicative of extensive demyelination, gliosis, and loss of axons in the involved white matter; the latter two events occur in the later stages of globoid cell leukodystrophy. In conjunction with brain MRI, these magnetic resonance spectroscopy findings may alert clinicians to the possibility of leukodystrophy in children with progressive encephalopathy.

Clinical and neuroradiological findings in classic infantile and late-onset globoid-cell leukodystrophy (Krabbe disease)

In the present study the clinical course and imaging of early and late-onset forms of Krabbe disease are analyzed. We report on 11 patients with a biochemical diagnosis of galactosyl ceramide beta-galactoside deficiency. Two presented as the classic infantile form and died within the second year of life. In 9 children the first clinical signs, such as gait difficulties and visual failure, started after age 2 years. All these patients developed slow regression of motor and mental capacities, and most of them died within their first decade. In patients of both groups computed tomography (CT) and magnetic resonance imaging (MRI) were performed. In the late-onset form, hypodensities of the central white matter and pyramidal tracts were the leading radiological signs, whereas in the early-onset form, hyperdensities and cerebellar white matter lesions were also detected. From our results it becomes clear that variability of Krabbe disease refers not only to clinical manifestation but also to CT and MRI findings. Better knowledge of phenotypic and radiological diversity will help to understand the pathogenesis of the disease.

[Krabbe's disease (globoid cell leukodystrophy). Apropos of 5 cases]

A clinical study on five cases of Krabbe's disease (globoid cell leukodystrophy) was performed. A final diagnosis was done either with post-mortem study (two cases) or by enzymatic assays carried on cultured fibroblasts (two cases). Peripheral nerve biopsy for electron microscopy was performed in all cases, and the ultrastructural alterations characteristics of Krabbe's disease were always found. The authors emphasize the suggestive clinical and laboratory data which enable the diagnosis of Krabbe's disease in the absence of the ultrastructural exam of peripheral nerve, or the enzymatic assays not performed in this country.

MR findings in leukodystrophy

Up to 5 years ago, the radiological diagnosis of leukodystrophy was based on computed tomography (CT). More recently, magnetic resonance imaging (MRI) has been used to study pathology of the white matter with great success. The abnormalities in eight patients with different types of leukodystrophy are described, using high-field MRI. CT and MRI show comparable sensitivity in detecting the pathological changes of leukodystrophy. MRI seems to be superior in visualizing the extent of the lesions, their precise anatomical location and any involvement of the brain stem and cerebellum. Differential diagnosis among the three types of leukodystrophy by MRI is difficult but may be attempted by some features. Specific diagnosis can be achieved only by laboratory examination or histology. The role of MRI should be to suggest the proper biochemical test at an earlier stage.