Abstract
BackgroundCocaine abuse is associated with several mechanisms of brain injury including ischemic, hemorrhagic and metabolic. Recently two case reports of leukoencephalopathy in cocaine users implicated a commonly used cocaine adulterant, levamisole. One well-documented adverse effect of levamisole, when used alone as antihelminthic or immunomodulatory drug, is multifocal inflammatory leukoencephalopathy. Therefore, immune mechanisms may also contribute to cocaine-induced brain injury.Case presentationsTwo cocaine users with multifocal leukoencephalopathy, treated with steroids and plasmapheresis, are described. The first is a 25-year-old man who presented with unilateral motor and sensory impairment progressing to bilateral deficits, dysphagia, dysarthria and confusion over several days. Serial MRI showed increasing abnormal FLAIR signal lesions with patchy restricted diffusion and heterogenous enhancement deep in the right and left hemispheres, including periventricular white matter as well as in the pons and cerebellar peduncle. The second patient is a 41-year-old woman who presented with confusion and impaired balance. MRI showed bilateral periventricular FLAIR lesions with scattered restricted diffusion and subtle gadolinium enhancement of some of the lesions. She initially stabilized with supportive care only, but after further cocaine use was re-admitted six weeks later with marked neurological deterioration and MRI showed prominent worsening of the lesions. Both patients received steroid and plasma exchange and showed substantial improvement clinically and on imaging, which was sustained during out-patient follow-up.ConclusionMultifocal leukoencephalopathy associated with cocaine use may have an inflammatory/immune basis, possibly related to levamisole contamination, at least in some patients. Three cases, including the present two, have been described wherein good neurological improvement was seen in association with steroid treatment. However, in the absence of appropriate clinical trials, it remains unknown whether immunotherapy is truly beneficial for these patients.
Highlights
Cocaine abuse is associated with several mechanisms of brain injury including ischemic, hemorrhagic and metabolic
Multifocal leukoencephalopathy associated with cocaine use may have an inflammatory/immune basis, possibly related to levamisole contamination, at least in some patients
Levamisole has immuno-stimulant properties that increase endogenous opiate levels in the brain and alter monoaminergic function [23]. These properties may be related, at least in part, to its popularity as a cocaine adulterant. It was first detected in cocaine samples in 2003 and by 2009 was present in over 70 % of cocaine specimens tested by the United States Drug Enforcement Agency [24]
Summary
The clinical and MRI improvement observed in our patients, subjected to steroids and plasmapheresis, supports the concept of an immune-mediated mechanism, possibly levamisole-induced, underlying cocaine neurotoxicity in some patients. Given the prevalence of cocaine use in the general population, patients presenting with white matter disease suggestive of acute disseminated encephalomyelitis or multiple sclerosis, with or without remissions and relapses, should be carefully reviewed with respect to cocaine use. Consent Both patients provided written informed consent for their cases and accompanying images to be published. Authors’ contributions As attending neurologists, RV and BS were involved in the direct care of the first and second patients, respectively Both authors prepared the results of investigations for publication, including the figures, and contributed to critical review of the literature and multiple drafts of the manuscript. Both authors have read and approve the final version of the manuscript
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
