Methadone-induced encephalopathy: a case series and literature review

Abstract

Background: Accidental ingestion or consumption of supra-therapeutic doses of methadone can result in neurological sequelae in humans. We aimed to determine the neurological deficits of methadone-poisoned patients admitted to a referral poisoning hospital using brain magnetic resonance (MR) and diffusion weighted (DW) imaging. Methods: In this retrospective study, brain MRIs of the patients admitted to our referral center due to methadone intoxication were reviewed. Methadone intoxication was confirmed based on history, congruent clinical presentation, and confirmatory urine analysis. Each patient had an MRI with Echo planar T1, T2, FLAIR, and DWI and apparent deficient coefficient (ADC) sequences without contrast media. Abnormalities were recorded and categorized based on their anatomic location and sequence. Results: Ten patients with abnormal MRI findings were identified. Eight had acute-and two had delayed-onset encephalopathy. Imaging findings included bilateral confluent or patchy T2 and FLAIR high signal intensity in cerebral white matter, cerebellar involvement, and bilateral occipito-parietal cortex diffusion restriction in DWI. Internal capsule involvement was identified in two patients while abnormality in globus pallidus and head of caudate nuclei were reported in another. Bilateral cerebral symmetrical confluent white matter signal abnormality with sparing of subcortical U-fibers on T2 and FLAIR sequences were observed in both patients with delayed-onset encephalopathy. Conclusions: Acute-and delayed-onset encephalopathies are two rare adverse events detected in methadoneintoxicated patients. Brain MRI findings can be helpful in detection of methadone-induced encephalopathy.

¿Psicosis luego de sobredosis por opioides? Lesión isquémica bilateral del globo pálido como causa orgánica insospechada.

“…Se reportó que el rendimiento para encontrar alteraciones intracraneanas en los pacientes con alteración mayor del estado de consciencia fue hasta del 20% (6). Con respecto a los hallazgos imagenológicos más frecuentemente encontrados en los pacientes que presentan intoxicaciones por opioides se incluyen: edema citotóxico, pseudo hemorragia subaracnoidea, leucoencefalopatía e infartos subcorticales (tabla 1) (7). Rev Neuropsiquiatr.…”

“…En la figura 3 se esquematizan los componentes clínicos del síndrome de neurotoxicidad inducida por opioides. Esquema de construcción propia de los autores con base en las referencias (7,25,26,27,28). A lo anterior debe sumarse la posibilidad de concurrencia del síndrome de neurotoxicidad inducida por opioides, el cual corresponde a una variedad de síntomas y signos característicos que se manifiestan en los pacientes que han estado expuestos a este tipo de medicamentos tanto de forma aguda como crónica (figura 3).…”

A case report of toxic leukoencephalopathy induced by metronidazole in a woman with surgical site infection

“… 11 The patient has also taking methadone, and there are reports of toxic leukoencephalopathy due to methadone. 12 …”

“…11 The patient has also taking methadone, and there are reports of toxic leukoencephalopathy due to methadone. 12 Toxic leukoencephalopathy should be considered in these patients, and suspected drug should be discontinued.…”

“…The majority of the cases present cerebellar dysfunction (dysarthria, ataxia, dysmetria, and nystagmus) followed by altered mental status and seizures, 5 chorea, myoclonus, 9,10 and pure sensorineural hearing loss are also reported 11 . The patient has also taking methadone, and there are reports of toxic leukoencephalopathy due to methadone 12 …”