Mimicking a Psychiatric Disorder: Heroin-Induced Leukoencephalopathy

Inverse pattern of GABAergic system impairment in the external versus internal globus pallidus in male heroin addicts

Opioid addiction is a global problem that has been exacerbated in the USA and Europe by the COVID-19 pandemic. The globus pallidus (GP) plays a prominent neurobiological role in the regulation of behaviour as an output station of the striato-pallidal system. GABAergic large projection neurons are the main neuronal type in the external (EGP) and internal (IGP) parts of the GP, where addiction-specific molecular and functional abnormalities occur. In these neurons, glutamate decarboxylase (GAD) with isoforms GAD 65 and 67 is a key enzyme in GABA synthesis, and experimental studies suggest GAD dysregulation in the GP of heroin addicts. Our study, which was performed on paraffin-embedded brains from the Magdeburg Brain Bank, aimed to investigate abnormalities in the GABAergic function of large GP neurons by densitometric evaluation of their GAD 65/67-immunostained thick dendrites. The study revealed a bilaterally decreased fibres density in the EGP paralleled by the increase in the IGP in 11 male heroin addicts versus 11 healthy controls (significant U-test P values). The analysis of confounding variables found no interference of age, brain volume, and duration of formalin fixation with the results. Our findings suggest a dysregulation of GABAergic activity in the GP of heroin addicts, which is consistent with experimental data from animal models and plays potentially a role in the disturbed function of basal ganglia circuit in opioid addiction.

The dangers of "Chasing the dragon": a fatal case of heroin-induced leukoencephalopathy

Heroin-induced leukoencephalopathy (HLE) is a rare toxic encephalopathy associated primarily with heroin inhalation, commonly referred to as "chasing the dragon." This study presents a clinical case of a 27-year-old polydrug user diagnosed with HLE during hospitalization for rapidly progressive flaccid tetraplegia and aphasia. The clinical manifestations encompassed cerebellar and bulbar dysfunction, coupled with motor impairment and altered consciousness. Based on the clinical data and MRI results, HLE was identified as the most likely cause. This article aims to provide insights into the clinical and radiological aspects of HLE, emphasizing the diagnostic significance of radiological findings. The gold standard examination for diagnosis is MRI, crucial due to the difficulties in obtaining histological confirmation for this rare condition.

Chasing the dragon and stumbling upon an octopus: A case of heroin-induced leukoencephalopathy and reverse takotsubo cardiomyopathy

The practice of heating heroin and inhaling its vapors, commonly referred to as “chasing the dragon” has been around for decades, but only gained popularity in the United States in the 1990s. Since then, there have been many documented cases of heroin-induced leukoencephalopathy (HIL) and takotsubo cardiomyopathy (TTC). This case highlights a patient with a history of heroin inhalation who presented with multiple neurological features, including bilateral upper and lower extremity weakness, blurry vision and slurred speech. Symptoms progressively worsened over the course of multiple weeks and brain imaging was consistent with toxic leukoencephalopathy secondary to heroin inhalation. Medical course was complicated by a rare associated feature of HIL: reverse Takotsubo cardiomyopathy (rTTC). Transesophageal echocardiogram demonstrated a classic basal hypokinesis and ballooning characteristic of rTTC. The patient's symptoms were treated as currently there is no guideline directed therapy for HIL or rTTC. This case demonstrated a rare and significant complication of heroin inhalation: HIL and rTTC and described potential therapies currently being studied.

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Heroin-induced leukoencephalopathy (HIL) is a rare neurological complication with possible contribution to the development of reverse Takotsubo cardiomyopathy (rTTC).

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HIL is a neurologic disorder associated with inhaling heroin vapors. The pathophysiology is poorly understood at this time, but the condition appears to affect mainly white matter in the brain, differentiating from other types of leukoencephalopathies.

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The diagnosis of rTTC is based on the presence of left ventricular basal hypokinesis or akinesis, acute electrocardiogram abnormalities or elevated troponin levels in the absence of any obstructive coronary disease or myocarditis.

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While there is currently no treatment regimen for HIL, antioxidants such as vitamin A, C, E, zinc, coenzyme q10, and selenium are usually recommended. However, further studies need to be conducted to assess the efficacy of the antioxidants in these patient populations.