Síndrome de Marchiafava-Bignami

Introdução

The syndrome was first described by Marchiafava and Bignami (two Italian pathologists) in 1903. Marchiafava-Bignami syndrome is a rare neurological disease characterised by necrosis and demyelination in the fibre tracts of the corpus callosum. It is commonly linked to prolonged, severe alcohol intake and malnutrition. It is most frequently seen in middle-aged or elderly alcoholic males.¹

• It is very rare; a literature review in 2001 found a total of 250 reported cases.² A further 50 cases were identified in a literature search in 2008.

• Many cases may go unreported, with clinical features merging with other underlying problems related to alcohol.³

• There seems to be no predilection for race, gender or geographical distribution.

Fatores de risco⁴

Most cases have been reported in male alcoholics aged over 45 years. It can occur in non-alcoholics who have malnutrition or frequent vomiting, particularly female and younger age groups.

The clinical presentation is variable and often non-specific.

• Most patients have a history of alcoholism and poor nutrição.

• Onset may be sudden with stupor, coma or convulsões.

• Other patients present with acute or chronic demência and/or gait problems. Spasticity often complicates the gait disorder.

• Other features include incontinência, hemiparesis, dysarthria and apraxia.

There are 3 clinical subtypes:

• Type A: main clinical features are coma, stupor and pyramidal tract features. Radiology reveals involvement of the entire corpus callosum.

• Type B: slightly impaired level of consciousness. Otherwise normal or mildly impaired status and the corpus callosum is only partially affected.

• Chronic: mainly have cognitive impairment.

Sinais

• Usually nonspecific.

• A generally dishevelled condition is suggestive of chronic alcohol problems.

• The patient may be lethargic, stuporous, or even unconscious (coma or seizures).

• Inability to retain new information, Korsakoff's syndrome, alcoholic neuropathy and delirium tremens suggestive of alcoholism.

• Dementia and aphasia may occur.

• Tremors, weakness, spasticity and gait abnormalities may also be present.

• Other brain lesions associated with alcoholism, eg, encefalopatia de Wernicke, hepatocerebral degeneration, head trauma, central pontine myelinolysis and pellagra.

• Infarction of the recurrent artery of Heubner, neoplastic conditions like lymphoma or astrocytoma, demyelinating conditions like esclerose múltipla, progressive multifocal leukoencephalopathy, or acute disseminated encephalomyelitis are among the other differential diagnoses..

Even in the absence of typical clinical symptoms, early diagnosis is possible because of advancements in brain imaging techniques, particularly MRI.

• Screening blood tests may be needed for patients presenting with altered consciousness, eg serum electrolyte and glucose levels, FBC and toxicology.

• CT scan: may show callosal damage but changes may be mild and not detected. It may, however, be required urgently to exclude haemorrhage or a mass.

• Lumbar puncture may also be performed after CT scanning to exclude infection.

• MRI: to delineate the problem clearly, and is the most sensitive imaging modality.⁷

• Electroencephalography (EEG): to evaluate seizures.

• Neuropsychological testing: can demonstrate difficulties with information transfer between the right and left brain.

• There is no particular treatment. Clinical recovery is accelerated by early diagnosis, thiamine, vitamin B complex, and folic acid treatment.

• Management of other problemas relacionados ao álcool: thiamine, vitamin B12, other B vitamins, folate, rehabilitation.

• Before the existence of CT scans, almost all patients were discovered at autopsy. They had usually died from alcohol-related problems and had had severe neuropsychological deficits prior to death.

• CT and MRI scanning allow detection of milder cases and some patients have recovered with minimal deficits. One documented case related to alcoholism completely recovered after treatment with intravenous vitamin B complex and methylprednisolone.⁹

• In those with alcoholism, the prognosis is poor unless the patient adheres to an alcohol treatment programme.

• Of the 250 patients reported in 2001, only 20 had a favourable outcome. 200 died and 30 remained bedridden or severely disabled.

• Recent studies of the subtypes suggest that type A had a much worse prognosis. The long-term disability rate for type A was 86% and the mortality rate 21%. The figures for type B were 19% and 0% respectively.

Prevention of problemas relacionados ao álcool is through education and mental health support.