The Emerging Role of Inhaled Heroin in the Opioid Epidemic: A Review

Opioid-Associated Nervous System Injuries

With the rise of the opioid epidemic, the practicing neurologist must recognize the patterns of a growing number of opioid-associated neurological injuries. This is in addition to the classic toxidrome of miosis, altered mental status, and respiratory depression, which must never be overlooked, as it is reversible and potentially lifesaving. Several other idiosyncratic syndromes due to opioid-related nervous system insults are defined by their characteristic imaging findings and portend variable functional recovery. Opioid toxicity can not only lead to brain injury, but also spinal cord and, rarely, peripheral nerve injury. As several newer synthetic opioids are undetectable by most assays, a low threshold to suspect opioid exposure must be maintained.

Exploring racial and secondary substance use differences in route of administration of opioid drugs: Analysis of the 2015-2019 treatment admission data

INTRODUCTION

The opioid crisis continues to evolve with increasing opioid-related overdose deaths among under-represented minorities. A better understanding of substance use differences in the route of administration for people using heroin and other opioids can lead to targeted strategies and interventions.

METHODS

Using the 2015-2019 Treatment Episode Data Set - Admissions (TEDS-A), a multinomial logistic regression model examined the relationship between race/ethnicity and secondary substance use with route of administration in a subset of 591,078 admissions.

RESULTS

For individuals reporting heroin as their primary substance, minoritized clients were both more likely to smoke (NH Blacks RR: 2.28, 95 % CI 2.16-2.41; Hispanic RR: 1.80, 95 % CI: 1.74, 1.87; Other RR: 2.09, 95 % CI: 2.00, 2.20) or inhale heroin (Hispanic RR: 1.82, 95 % CI 1.78-1.85; Other RR: 1.30, 95 % CI 1.25, 1.34) compared to non-Hispanic (NH) Whites. NH Black clients were nearly seven and a half times more likely to report inhaling (RR: 7.45, 95 % CI 7.28, 7.62) heroin over injecting it. Clients were more likely to smoke heroin compared to injection if they reported secondary drug use of methamphetamines (RR: 2.28, 95 % CI 2.21, 2.35) and other opioids (RR: 1.21, 95 % CI 1.15, 1.28). For clients reporting other opioids as their primary substance, Hispanic (RR: 1.33, 95 % CI 1.19, 1.47) and other racial/ethnic minority clients (RR: 2.50, 95 % CI 2.23, 2.79) were more likely to smoke opioids vs take it orally compared to their NH White counterparts. Individuals who reported methamphetamine use as a secondary substance were significantly more than three times as likely to smoke (RR: 3.07, 95 % CI 2.74, 3.45) or inject (RR: 3.36, 95 % CI 3.17, 3.57) compared to orally ingesting opioids, while those who reported cocaine or crack cocaine use were more than twice as likely to inject (RR: 2.22, 95 % CI 2.09-2.36) opioids than taking them orally.

CONCLUSION

Findings demonstrate significant racial and ethnic differences in the route of administration. This work expands on the understanding of the complex nature of polysubstance use in the evolving opioid crisis and the secondary substance use of clients on routes of administration of opioids and heroin, highlighting the need for tailored interventions to address the treatment needs of under-represented minorities.

Clinical and neuroradiographic features of fentanyl inhalation-induced leukoencephalopathy

A man in his late 40s with no known past medical history was unresponsive for an unknown period of time. Crushed pills and white residue were found on a nearby table. On presentation he was obtunded and unresponsive to verbal commands but withdrawing to painful stimuli. The initial urine drug screen was negative, but a urine fentanyl screen was subsequently positive with a level of 137.3 ng/mL. MRI of the brain showed reduced diffusivity and fluid attenuated inversion recovery (FLAIR) hyperintensity symmetrically in the bilateral supratentorial white matter, cerebellum and globus pallidus. Alternative diagnoses such as infection were considered, but ultimately the history and workup led to a diagnosis of fentanyl-induced leukoencephalopathy. Three days after admission the patient became able to track, respond to voice and follow basic one-step commands. The patient does not recall the mechanism of inhalation. While there are case reports of heroin-induced leukoencephalopathy following inhaled heroin use and many routes of fentanyl, this is the first reported case of a similar phenomenon due to fentanyl inhalation.

A neuropsychiatric case of delayed post-hypoxic leukoencephalopathy from opioid intoxication resulting in Anton-Babinski syndrome and quadriplegia

This is the case of a 26-year-old male who developed Anton Babinski syndrome (ABS), quadriplegia, and delayed post-hypoxic leukoencephalopathy (DPHL) after an opioid overdose. He exhibited cortical blindness, visual anosognosia, and confabulation upon awakening. Several days later, he experienced acute psychosis and agitation. T2-FSE MRI revealed extensive supratentorial leukoencephalopathy involving both cerebral hemispheres, extending to the posterior corpus callosum due to cerebral anoxia. This case report will discuss different types of encephalopathy from opioid abuse, ABS, visual anosognosia, and confabulation's pathogenic mechanisms. It underscores the necessity of researching substance-induced neuropsychiatric disorders and their pathogenic mechanisms for effective treatments.

Toxic leukoencephalopathy versus delayed post-hypoxic leukoencephalopathy after oral morphine sulphate overdose

Toxic leukoencephalopathy (TLE) is a rare pathology caused by various substances including opioids (notably heroin), immunosuppressants, chemotherapy agents, cocaine, alcohol and carbon monoxide. However, although heroin is metabolised by the body into morphine, there is a striking paucity in cases of primary oral morphine-induced TLE, especially in the adult population. We present the case of a man in his 40s admitted to hospital in respiratory depression with a Glasgow Coma Scale (GCS) score of 6 after taking an overdose of oral morphine sulphate. Following a complete recovery to baseline, he was then readmitted with an acute deterioration in his neurobehavioural condition. Initial investigations returned normal but MRI showed changes characteristic for TLE.In cases of opioid toxicity such as ours, TLE is difficult to differentiate from delayed post-hypoxic leukoencephalopathy, due to their similar clinical presentation, disease progression and radiological manifestation. We explore how clinicians can approach this diagnostic uncertainty.

Inhalational Heroin Use and Leukoencephalopathy: A Case Report

Heroin-induced leukoencephalopathy (HLE) is a rare condition with acute and chronic outcomes ranging from mild neurological symptoms to severe neurological deficits and death. HLE is caused by cerebral white matter damage secondary to exposure to toxic agents such as chemotherapeutic drugs, environmental toxins, and drugs of abuse. Here, we present the case of a 20-year-old woman with a past medical history significant for bipolar disorder and opioid use who presented to the emergency department with ataxia, involuntary movements, and altered mental status secondary to inhalational heroin use. The patient presented with symptoms including agitation, tremors, speech difficulty, confusion, memory loss, and weakness. Magnetic resonance imaging (MRI) showed diffuse cerebral atrophy and electroencephalography (EEG) was significant for cerebral dysfunction in the left hemisphere and diffuse encephalopathy. The patient was treated with intravenous (IV) steroids, vitamins, and fluids but failed to show improvement. She was subsequently discharged to hospice 17 days after admission. There are few reported cases of toxic leukoencephalopathy due to heroin inhalation. The patient's young age and presentation following one month of abstinence are particularly unique as she suffered an acute decompensation with severe, lasting neurological deficits. This case highlights a potential presentation of HLE and seeks to increase clinical recognition in patients with a recent history of substance use and unexplained neurological symptoms.

Heroin and its metabolites: relevance to heroin use disorder

Heroin is an opioid agonist commonly abused for its rewarding effects. Since its synthesis at the end of the nineteenth century, its popularity as a recreational drug has ebbed and flowed. In the last three decades, heroin use has increased again, and yet the pharmacology of heroin is still poorly understood. After entering the body, heroin is rapidly deacetylated to 6-monoacetylmorphine (6-MAM), which is then deacetylated to morphine. Thus, drug addiction literature has long settled on the notion that heroin is little more than a pro-drug. In contrast to these former views, we will argue for a more complex interplay among heroin and its active metabolites: 6-MAM, morphine, and morphine-6-glucuronide (M6G). In particular, we propose that the complex temporal pattern of heroin effects results from the sequential, only partially overlapping, actions not only of 6-MAM, morphine, and M6G, but also of heroin per se, which, therefore, should not be seen as a mere brain-delivery system for its active metabolites. We will first review the literature concerning the pharmacokinetics and pharmacodynamics of heroin and its metabolites, then examine their neural and behavioral effects, and finally discuss the possible implications of these data for a better understanding of opioid reward and heroin addiction. By so doing we hope to highlight research topics to be investigated by future clinical and pre-clinical studies.

Heroin-Induced Leukoencephalopathy Leading to Locked-In Syndrome: A Case Report

Heroin-induced leukoencephalopathy (HLE) is a rare neurological sequela of heroin use. Heroin can be consumed through different routes such as inhalation, intravenous injection, and snorting. HLE cases have been reported via each route. However, heroin vapor inhalation has a higher rate of HLE and is also known as "chasing the dragon syndrome." We present a 65-year-old male who came unresponsive after heroin intoxication. During the hospital stay, he developed locked-in syndrome secondary to brain damage by HLE sequelae.

Heroin use and neuropsychological impairments: comparison of intravenous and inhalational use

BACKGROUND AND OBJECTIVES

Injection and inhalational heroin use are associated with different levels of brain exposure to heroin and its metabolites and differences in the severity of dependence, which might lead to differential impacts on neuropsychological functions. We examined the difference and the magnitude of difference in the neuropsychological functions between inhalational and injection heroin-dependent subjects and also compared them with healthy controls.

METHODS

The study sample comprised three groups: 73 subjects with injection heroin dependence, 74 with inhalational heroin dependence, and 75 healthy controls (HC). We excluded patients with HIV, head injury, epilepsy, and severe mental illness. Neuropsychological assessments were done by Standard Progressive Matrices, Wisconsin Card Sorting Test (WCST), Iowa Gambling Task, Trail-Making Tests A and B (TMT), and Verbal and Visual Memory 1 and 2 Backtests (NBT). We estimated independent effects of the groups on various neuropsychological test parameters, adjusted for age and duration of dependence.

RESULTS

In the WCST, the inhalational heroin-dependent group took more trials to complete the first category and had higher scores in the failure to maintain set than controls. The intravenous group had higher total errors than controls in verbal working memory tests and Visual Working Memory 2 Backtest. This group scored higher commission errors in the Verbal 2 Backtest than the controls. The two groups of heroin users differed in failure to maintain set and Verbal Working Memory 2 Backtests. The effect sizes of the group differences were modest.

CONCLUSION AND SCIENTIFIC SIGNIFICANCE

Either route of heroin use is associated with cognitive impairments; inhalational and injection use involve different cognitive domains.

The long-term effects of repeated heroin vapor inhalation during adolescence on measures of nociception and anxiety-like behavior in adult Wistar rats

RATIONALE

Adolescents represent a vulnerable group due to increased experimentation with illicit substances that is often associated with the adolescent period, and because adolescent drug use can result in long-term effects that differ from those caused by drug use initiated during adulthood.

OBJECTIVES

The purpose of the present study was to determine the effects of repeated heroin vapor inhalation during adolescence on measures of nociception, and anxiety-like behavior during adulthood in female and male Wistar rats.

METHODS

Rats were exposed twice daily to 30 min of heroin vapor from post-natal day (PND) 36 to PND 45. At 12 weeks of age, baseline thermal nociception was assessed across a range of temperatures with a warm-water tail-withdrawal assay. Anxiety-like behavior was assessed in an elevated plus-maze (EPM) and activity was measured in an open-field arena. Starting at 23 weeks of age, baseline thermal nociception was re-assessed, nociception was determined after acute heroin or naloxone injection, and anxiety-like behavior was redetermined in the EPM.

RESULTS

Adolescent heroin inhalation altered baseline thermal nociception in female rats at 12 weeks of age and in both female and male rats at ~ 23 weeks. Heroin-treated animals exhibited anxiety-like behavior when tested in the elevated plus-maze, showed blunted heroin-induced analgesia, but exhibited no effect on naloxone-induced hyperalgesia.

CONCLUSIONS

The present study demonstrates that heroin vapor inhalation during adolescence produces behavioral and physiological consequences in rats that persist well into adulthood.

Neuroimaging for differential diagnosis of transient neurological attacks

BACKGROUND

Rapid yet comprehensive neuroimaging protocols are required for patients with suspected acute stroke. However, stroke mimics can account for approximately one in five clinically diagnosed acute ischemic strokes and the rate of thrombolyzed mimics can be as high as 17%. Therefore, to accurately determine the diagnosis and differentiate mimics from true transient ischemic attacks, acute ischemic stroke is a challenge to every clinician.

DISCUSSION

Medical history and neurological examination, noncontract head computed tomography, and routine magnetic resonance imaging play important roles in the assessment and management of patients with transient neurological attacks in the emergency department. This review attempts to summarize how neuroimaging can be utilized to help differentiate the most common mimics from transient ischemic attack and acute ischemic stroke.

CONCLUSION

Although imaging can help direct critical triage decisions for intravenous thrombolysis or endovascular therapy, more detailed medical history and neurological examination are crucial for making a prompt and accurate diagnosis for transient neurological attack patients.

Heroin pipe distribution to reduce high-risk drug consumption behaviors among people who use heroin: a pilot quasi-experimental study

BACKGROUND

Heroin pipe distribution may encourage people who use heroin (PWUH) to transition from injecting to smoking heroin, reducing harms associated with injection drug use. A syringe services program (SSP) in Seattle, Washington, led by people who use drugs developed a heroin pipe distribution program.

METHODS

We conducted a pretest-posttest quasi-experimental study to evaluate the impact of heroin pipe distribution on drug consumption behaviors among PWUH between March and December 2019. SSP clients were surveyed during three weeklong timepoints before and four weeklong timepoints after heroin pipe distribution. Primary outcomes were change in proportion of SSP clients who exclusively injected heroin, exclusively smoked heroin, and both injected and smoked heroin in the past seven days comparing the pre- and post-intervention periods.

RESULTS

Across the seven observation timepoints, 694 unique respondents completed 957 surveys. Multiple responses from a single respondent in a given period were collapsed, resulting in 360 pre-intervention and 430 post-intervention records. Heroin use was reported in over half of pre-intervention (56%, 201/360) and post-intervention records (58%, 251/430). Compared to pre-intervention behaviors, the proportion of respondents who exclusively injected heroin was lower after the start of heroin pipe distribution (32%, 80/251 vs 43%, 86/201, p = 0.02), while the proportion of respondents who both injected and smoked heroin was higher (45%, 113/251 vs 36%, 72/201, p = 0.048). Just under half (44%, 110/251) of respondents who used heroin during the post-intervention period used a heroin pipe obtained from the SSP, of which 34% (37/110) reported heroin pipe distribution had reduced their heroin injection frequency. Self-reported hospitalization for a pulmonary cause was not associated with using a heroin pipe.

CONCLUSIONS

The proportion of SSP clients who exclusively injected heroin was lower after implementation of heroin pipe distribution. Randomized studies with longer follow-up are needed to investigate whether heroin pipe distribution reduces heroin injection and improves health outcomes associated with drug use. Limited intervention exposure, loss to follow-up, and pipe availability from other sources pose methodological challenges to evaluations of route transition interventions in community settings. This pilot highlights the potential for organizations led by people who use drugs to develop, implement, and evaluate novel public health programming.

Two Cases Comparing the Presentations and Outcomes of Heroin-induced Toxic Leukoencephalopathy

Heroin-induced toxic leukoencephalopathy (TLE) is an uncommon condition that presents with nonspecific and variable neuropsychiatric findings. It may result in satisfactory recovery or death. Traditionally referred to as "chasing the dragon" syndrome and associated with inhalation of pyrolyzed heroin, recent publications have reported forms of the syndrome associated with noninhaled heroin. We report 2 cases of heroin-induced TLE associated with noninhaled routes of administration and a well-documented history of opioid use disorder. The patient in the first case presented with moderate to severe symptoms. Magnetic resonance imaging of the brain revealed increased T2 and fluid-attenuated inversion recovery signals bilaterally throughout subcortical and periventricular white matter. She survived with significant cognitive issues at discharge from which she adequately recovered by 11-month follow up. The patient in the second case presented with severe symptoms. Magnetic resonance imaging of the brain showed diffuse abnormal increased T2 and fluid-attenuated inversion recovery signals in the white matter of the centrum semiovale and corona radiata. The patient died within 3 weeks of presentation. Both cases illustrate the underrecognition of the form of TLE associated with noninhaled heroin and the difficulties involved in confirming recent heroin use that likely delayed the diagnosis. Further, noninhaled heroin-induced TLE can present with specific signs and symptoms that may help clinicians delineate it from the inhaled form. Given the ongoing opioid epidemic, early and accurate recognition of this condition is of paramount importance.

6-Monoacetylmorphine-antibody distribution in tissues from heroin-related death cases: An experimental study to investigate the distributive response

Heroin, a semisynthetic opioid drug synthesized from morphine, is the 3,6-diacetyl ester of morphine (diacetylmorphine). The post-mortem diagnosis of heroin-related death could be an issue and usually rely on a combination of investigations, including the autopsy, histological and toxicological analysis. We conducted the present study to evaluate the correlation between the heroin concentration in biological fluids (peripheral blood, bile and urine) and the post-mortem anti-6-MAM antibody expression in various tissues (brain, heart, lung, liver and kidney) using immunohistochemical staining. A quantitative analysis of the immunohistochemical reaction was carried out. 45 cases of heroin-related death investigated at the Forensic Pathology Institutes of the University of Rome, Foggia and Pisa were included. The control group was composed of 15 cases of death due to other causes, without brain lesions and negative toxicological analysis for drugs. We found a positive immunohistochemical reaction in different organs and it was related to the timing of heroin metabolization. No reaction was found in the control group. Our findings show that immunohistochemistry can be a valuable tool for the post-mortem diagnosis of acute heroin abuse. A better understanding of the timing of heroin's metabolism can be useful in the forensic field and for future therapeutic applications.

Neuroimaging Findings in CHANTER Syndrome: A Case Series

Recently, a distinct clinicoradiologic entity involving cerebellar, hippocampal, and basal nuclei transient edema with restricted diffusion (CHANTER) on MR imaging was identified. Patients present in an unresponsive state following exposure to drugs of abuse. Very little information exists regarding this entity, particularly in the radiology literature. We identify and describe 3 patients at our institution with similar clinical and radiographic findings. Multifocal restricted diffusion in the brain is typically associated with poor outcomes. By contrast, CHANTER involves intraventricular obstructive hydrocephalus that, when treated, can lead to substantial recovery. This novel syndrome should be on the differential in patients who present in an unresponsive state after recent opioid use in the context of the above imaging findings. Additional diagnoses on the differential can include ischemic stroke, hypoxic-ischemic encephalopathy, "chasing the dragon," leukoencephalopathy, opioid-associated amnestic syndrome, and pediatric opioid-use-associated neurotoxicity with cerebellar edema.

Leukoencephalopathy due to inhalational and trans-conjunctival heroin abuse: First case report from Pakistan

Introduction

and importance: Heroin-induced leukoencephalopathy (HLE) is a rare illness that causes diffuse white matter destruction, leading to acute or subacute development of neurological signs and symptoms. Physicians must be aware of the likely clinical presentation to properly evaluate and diagnose this clinical entity.

Case presentation

We report the case of a young gentleman who presented with acute stupor following his first instance of heroin vapor inhalation. He later confessed to trans-conjunctival application of the drug as well. His Glasgow Coma Scale (GCS) score improved within four days of admission, however, the neurologic sequalae such as cognitive impairment, spastic paraparesis and urge incontinence only partially resolved at three months. Abnormal white matter hyperintensities with restricted diffusion on brain magnetic resonance imaging and history of heroin abuse led to diagnosis of toxic leukoencephalopathy.

Clinical discussion

Leukoencephalopathy with heroin is mostly observed after inhalation (i.e., “chasing the dragon”) but other routes of abuse have also been reported. Although a large spectrum of presentations exists, altered mental status, cerebellar dysfunction and fecal/urinary incontinence are the most commonly seen presenting features. Anti-oxidant therapy has shown promising results in terms of treatment.

Conclusion

The growing rates of opioid use disorders require physicians to be aware of and counsel the patients regarding dangerous neurological sequelae of these drugs.

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Heroin-induced leukoencephalopathy (HLE) is a rare entity that can present with neurobehavioral symptoms and focal neurological deficits.

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It is most common after inhalation but trans-conjunctival abuse may cause it as well.

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The growing rates heroin abuse require physicians to be aware of and counsel the patients regarding HLE.

Examining prevalence and correlates of smoking opioids in British Columbia: opioids are more often smoked than injected

BACKGROUND

British Columbia (BC) is in the midst of an opioid overdose crisis. Since 2017, smoking illicit drugs has been the leading mode of drug administration causing overdose death. Yet, little is known about people who smoke opioids, and factors underlying choice of mode of administration. The study objectives are to identify the prevalence and correlates associated with smoking opioids.

METHODS

The Harm Reduction Client Survey is a monitoring tool used by the BC Centre for Disease Control since 2012. This survey is disseminated to harm reduction sites across BC to understand drug use trends and drug-related harms. We examined data from the survey administered October-December 2019 and performed descriptive, univariate, and multivariate analyses to better understand factors associated with smoking opioids.

RESULTS

A total of 369 people who used opioids in the past 3 days were included, of whom 251 (68.0%) reported smoking opioids. A total of 109 (29.5%) respondents experienced an overdose in the past 6 months; of these 79 (72.5%) smoked opioids. Factors significantly associated with smoking opioids were: living in a small community (AOR =2.41, CI =1.27-4.58), being a woman (AOR = 1.84, CI = 1.03-3.30), age under 30 (AOR = 5.41, CI = 2.19-13.40) or 30-39 (AOR = 2.77, CI = 1.33-5.78) compared to age ≥ 50, using drugs alone (AOR = 2.98, CI = 1.30-6.83), and owning a take-home naloxone kit (AOR = 2.01, CI = 1.08-3.72). Reported use of methamphetamines within the past 3 days was strongly associated with smoking opioids (AOR = 6.48, CI = 3.51-11.96).

CONCLUSIONS

Our findings highlight important correlates associated with smoking opioids, particularly the recent use of methamphetamines. These findings identify actions to better respond to the overdose crisis, such as targeted harm reduction approaches, educating on safer smoking, advocating for consumption sites where people can smoke drugs, and providing a regulated supply of opioids that can be smoked.

Transition from injecting opioids to smoking fentanyl in San Francisco, California

BACKGROUND

The introduction of illicitly made fentanyl in the United States has slowly replaced heroin. New illicit drugs are often associated with changes in frequency and modes of administration. We assessed changes in injection frequency and smoking fentanyl in the new era of fentanyl availability in San Francisco.

METHODS

We used targeted sampling to recruit 395 people who inject drugs (PWID) into an observational cohort study in San Francisco 2018-2020. We assessed changes in injection frequency, opioid injection frequency and fentanyl smoking frequency in four six-month periods. We also conducted qualitative interviews with PWID asking about motivations for injecting and smoking opioids.

RESULTS

The median number of past-month injections steadily decreased by semi-annual calendar year from 92 injections in July to December 2018 to 17 injections in January to June 2020. The rate of opioid injections reduced by half (Adjusted Incidence Rate Ratio = 0.41; 95 % Confidence Interval = 0.25, 0.70; p < 0.01). The number of days smoking fentanyl was associated with fewer number of injections (X2(2) = 11.0; p < 0.01). Qualitative interviews revealed that PWID's motivation for switching from injecting tar heroin to smoking fentanyl was related to difficulties accessing veins. After switching to smoking fentanyl, they noticed many benefits including how the drug felt, improved health, fewer financial constraints, and reduced stigma.

CONCLUSION

Between 2018 and 2020, there was a shift from injecting tar heroin to smoking fentanyl in San Francisco. Reductions in injection of illicit drugs may offer public health benefit if it reduces risk of blood-borne viruses, abscesses and soft-tissue infections, and infective endocarditis.

Qualitative LC/Q-TOF Analysis of Umbilical Cord Tissue via Data-Dependent Acquisition as an Indicator of In Utero Exposure to Toxic Adulterating Substances

Toxic adulterants are drug or chemical agents used to add bulk volume to traditional drugs of abuse such as cocaine, and heroin. These cutting agents include levamisole, metamizole, noxiptillin, phenacetin, and xylazine as well as common legal drugs such as acetaminophen, caffeine, diphenhydramine, lidocaine, quinine, quetiapine, and tramadol. Because they possess pharmacological activity they result in exposure of the user, but also in the case of pregnant women, the developing fetus, to potential drug toxicity. We describe the development, validation, and implementation of a rapid (48 second sample-to-sample) test based on a qualitative data-dependent liquid chromatography-quadrupole time of flight mass spectrometry (LC/Q-TOF) method for the analysis of toxic adulterating substances in umbilical cord tissue (UCT) samples. The method provides a means of studying potential in utero exposure to these agents. Library spectra comparison at 3 different collision energies was used in conjunction with retention time and accurate mass to identify these substances in UCT. Analytically based reporting limits were established to determine positivity rates of adulterants in UCT utilizing a standard addition approach. The method was applied to authentic cocaine and opioid positive UCT's to screen for toxic adulterants. There were a total of 82 potential adulterant positives found in a 30-sample cohort of authentic UCT samples, with an average of 2.7 substances per case. Lidocaine was the predominant finding followed by caffeine, and diphenhydramine all of which could result from non-illicit drug exposure, however, there were positives for levamisole, phenacetin, noxiptillin, and xylazine none of which are approved in the United States for human therapeutic use. This initial set of data established a preliminary positivity rate of potentially toxic adulterants in UCT samples positive for cocaine or opioid use.

Spongiform leukoencephalopathy: A unique case of biopsy confirmed leukoencephalopathy secondary to toxic, non-inflammatory exposure

Toxin-induced leukoencephalopathy is a rare neurological condition that has been previously associated with intracranial radiation, chemotherapy, drugs of abuse, and environmental exposures. Herein, we present a patient with brain-biopsy proven toxin-induced leukoencephalopathy, likely secondary to multiple environmental offenders including insecticides and non-Food and Drug Administration approved anabolic steroids, opioids, and benzodiazepines. A 60-year-old man presented to our service as a direct transfer from an outside facility for evaluation of a rapidly progressive neuropsychiatric decline. Extensive workup with blood work, cerebrospinal fluid analysis, paraneoplastic panel, serial magnetic resonance imaging brain with and without contrast, and electroencephalograms were unrevealing. Magnetic resonance imaging brain showed diffuse confluent white matter disease, which was non-specific. The patient was treated with high-dose methylprednisolone and trials of intravenous immunoglobulin without any significant improvement. Finally, a brain biopsy was performed, and pathology confirmed a spongiform leukoencephalopathy, favoring a toxin-related etiology. The diagnosis of toxin-induced leukoencephalopathy should be considered in patients with steep neuropsychiatric decline and associated diffuse white matter disease. Diagnosis relies heavily on history of exposure, clinical presentation, imaging findings, and ultimately, histopathology from brain biopsy. The recognition of the clinical presentation is important to pursue the appropriate diagnostic workup and treatment.

Neurocognitive impairments and brain abnormalities resulting from opioid-related overdoses: A systematic review

BACKGROUND

Non-fatal opioid-related overdoses have increased significantly over the past two decades and there have been increasing reports of brain injuries and/or neurocognitive impairments following overdose events. Limited preclinical research suggests that opioid overdoses may cause brain injury; however, little is known about such injuries in humans. The purpose this systematic review is to summarize existing studies on neurocognitive impairments and/or brain abnormalities associated with an opioid-related overdose in humans.

METHODS

PubMed, Web of Science, Ovid MEDLINE and PsyINFO were searched, without year restrictions, and identified 3099 articles. An additional 24 articles were identified by reviewing references. Articles were included if they were published in English, reported study findings in humans, included individuals 18 years of age or older, and reported an objective measure of neurocognitive impairments and/or brain abnormalities resulting from an opioid-related overdose. Six domains of bias (selection, performance, attrition, detection (two dimensions) and reporting were evaluated and themes were summarized.

RESULTS

Seventy-nine journal articles, published between 1973-2020, were included in the review. More than half of the articles were case reports (n = 44) and there were 11 cohort studies, 18 case series, and 6 case-control studies. All of the studies were categorized as at-risk of bias, few controlled for confounding factors, and methodological differences made direct comparisons difficult. Less than half of the studies reported toxicology results confirming an opioid-related overdose; 64.6 % reported brain MRI results and 27.8 % reported results of neuropsychological testing. Only two studies had within subject comparative data to document changes in the brain possibly associated with an overdose. Despite these limitations, existing publications suggest that brain injuries and neurocognitive impairments are associated with opioid overdose. Additional research is needed to establish the incidence of overdose-related brain injuries and the potential impact on functioning, as well as engagement in treatment of substance use disorders.

CONCLUSIONS

Respiratory depression is a defining characteristic of opioid overdose and prolonged cerebral hypoxia may cause brain injuries and/or neurocognitive impairments. The onset, characteristics, and duration of such injuries is variable and additional research is needed to understand their clinical implications.

Opioid-Associated Out-of-Hospital Cardiac Arrest: Distinctive Clinical Features and Implications for Health Care and Public Responses: A Scientific Statement From the American Heart Association

Opioid overdose is the leading cause of death for Americans 25 to 64 years of age, and opioid use disorder affects >2 million Americans. The epidemiology of opioid-associated out-of-hospital cardiac arrest in the United States is changing rapidly, with exponential increases in death resulting from synthetic opioids and linear increases in heroin deaths more than offsetting modest reductions in deaths from prescription opioids. The pathophysiology of polysubstance toxidromes involving opioids, asphyxial death, and prolonged hypoxemia leading to global ischemia (cardiac arrest) differs from that of sudden cardiac arrest. People who use opioids may also develop bacteremia, central nervous system vasculitis and leukoencephalopathy, torsades de pointes, pulmonary vasculopathy, and pulmonary edema. Emergency management of opioid poisoning requires recognition by the lay public or emergency dispatchers, prompt emergency response, and effective ventilation coupled to compressions in the setting of opioid-associated out-of-hospital cardiac arrest. Effective ventilation is challenging to teach, whereas naloxone, an opioid antagonist, can be administered by emergency medical personnel, trained laypeople, and the general public with dispatcher instruction to prevent cardiac arrest. Opioid education and naloxone distributions programs have been developed to teach people who are likely to encounter a person with opioid poisoning how to administer naloxone, deliver high-quality compressions, and perform rescue breathing. Current American Heart Association recommendations call for laypeople and others who cannot reliably establish the presence of a pulse to initiate cardiopulmonary resuscitation in any individual who is unconscious and not breathing normally; if opioid overdose is suspected, naloxone should also be administered. Secondary prevention, including counseling, opioid overdose education with take-home naloxone, and medication for opioid use disorder, is important to prevent recurrent opioid overdose.

Hoots and harm reduction: a qualitative study identifying gaps in overdose prevention among women who smoke drugs

BACKGROUND

Smoking or inhaling illicit drugs can lead to a variety of negative health outcomes, including overdose. However, most overdose prevention interventions, such as supervised consumption services (SCS), prohibit inhalation. In addition, women are underrepresented at SCS and are disproportionately impacted by socio-structural violence. This study examines women's experiences smoking illicit drugs during an overdose epidemic, including their utilization of a women-only supervised inhalation site.

METHODS

Qualitative research methods included on-site ethnographic observation and semi-structured interviews with 32 participants purposively recruited from the women-only site. Data were coded and analyzed using NVivo 12 and thematic analysis was informed by gendered and socio-structural understandings of violence.

RESULTS

Participants had preferences for smoking drugs and these were shaped by their limited income, inability to inject, and perceptions of overdose risk. Participants expressed the need for services that attend to women's specific experiences of gendered, race-based, and structural violence faced within and outside mixed-gender social service settings. Results indicate a need for sanctioned spaces that recognize polysubstance use and drug smoking, accommodated by the women-only SCS. The smoking environment further fostered a sociability where participants could engage in perceived harm reduction through sharing drugs with other women/those in need and were able to respond in the event of an overdose.

CONCLUSIONS

Findings demonstrate the ways in which gendered social and structural environments shape women's daily experiences using drugs and the need for culturally appropriate interventions that recognize diverse modes of consumption while attending to overdose and violence. Women-only smoking spaces can provide temporary reprieve from some socio-structural harms and build collective capacity to practice harm reduction strategies, including overdose prevention. Women-specific SCS with attention to polysubstance use are needed as well as continued efforts to address the socio-structural harms experienced by women who smoke illicit drugs.

Heroin-Induced Leukoencephalopathy

Heroin-induced leukoencephalopathy (HLE) is a rare but potentially debilitating and sometimes fatal neurological disorder. Despite the widely practiced heroin use via different routes and modalities, the syndrome is said to be rare and mostly associated with inhaling rather than injecting or snorting practices. We reviewed the literature to address the latest diagnostic, therapeutic, and prognostic measures related to the condition. Here, we present a case of a 35-year-old male who admitted to inhaling heroin 18 days ago and has been experiencing ongoing neurological symptoms for the past 17 days. Imaging was consistent with extensive white matter disease at multiple levels and different anatomical regions. Although there is no known cure for HLE, the patient benefited, somewhat, from antioxidants and physical rehabilitation.

Female rats self-administer heroin by vapor inhalation

Over the last two decades the United States has experienced a significant increase in the medical and non-medical use of opioid drugs, resulting in record numbers of opioid-related overdoses and deaths. There was an initial increase in non-medical use of prescription opioids around 2002, followed later by increased heroin use and then most recently fentanyl. Inhalation is a common route of administration for opioids, with a documented history spanning back to Mediterranean antiquity and up through modern use with e-cigarette devices. Unfortunately, preclinical studies using inhalation as the route of administration remain relatively few. This study was conducted to determine the efficacy of e-cigarette vapor inhalation of heroin in rats. Non-contingent exposure to heroin or methadone vapor produced anti-nociceptive efficacy in male and female rats. Female rats were trained to self-administer heroin vapor; the most-preferring half of the distribution obtained more vapor reinforcers when the concentration of heroin was reduced in the vapor vehicle and when pre-treated with the opioid receptor antagonist naloxone. The anti-nociceptive effect of heroin self-administered by vapor was identical in magnitude to that produced by intravenous self-administration. Finally, anxiety-like behavior increased 24-48 h after last heroin vapor access, consistent with withdrawal signs observed after intravenous self-administration. In sum, these studies show that rewarding and anti-nociceptive effects of heroin are produced in rats by vapor inhalation using e-cigarette technology. Importantly, self-administration models by this route can be deployed to determine health effects of inhaled heroin or other opioids.

Toxic Leukoencephalopathy due to Inhalational Heroin Abuse

Heroin-induced spongiform leukoencephalopathy (HSLE) is a rare condition that is strongly associated with heroin vapor inhalation which has become a popular method among heroin addicts because it poses a less immediate danger to the user and makes the drug much easier to use. We present a case of a 22-year-old male who presented with dysarthria and cerebellar symptoms starting, after 3 months of heroin inhalation. Diagnosis was confirmed to be HSLE after extensive diagnostic testing. HSLE is a rare complication of which the pathogenesis is poorly understood. Clinical history and characteristic findings on magnetic resonance imaging (diffuse, symmetric T2-hyperintensity, and diffusion restriction in frontal, parietal, occipital lobs, basal ganglia, and superior cerebellum) are diagnostic; however, care should be taken to exclude other etiologies. Treatment is primarily supportive; however, there is anecdotal evidence that coenzyme Q10 may be of benefit. The growing number of victims of the opioid crisis requires that physicians be aware of and counsel patients on the devastating neurological complications that can occur with abuse of these drugs.

A vapor exposure method for delivering heroin alters nociception, body temperature and spontaneous activity in female and male rats

BACKGROUND

The ongoing crisis related to non-medical use of opioids makes it of continued importance to understand the risk factors for opioid addiction, the behavioral and neurobiological consequences of opioid exposure and to seek potential avenues for therapy. Pre-clinical rodent models have been critical to advancing understanding of opioid consequences for decades, but have been mostly limited to drug delivery by injection or by oral dosing. Inhalation, a significant route for many human users, has not been as well-established.

METHOD

We adapted an e-cigarette based exposure system, previously shown efficacious for delivery of other drugs to rats, to deliver heroin vapor. Effectsin vivo were assessed in male and female Sprague-Dawley rats using a warm-water assay for anti-nociception and an implanted radiotelemetry system for evaluating changes in body temperature and spontaneous activity rate.

RESULTS

Inhalation of vapor created by heroin 100 mg/mL in the propylene glycol (PG) vehicle significantly slowed tail-withdrawal from a 52 °C water bath, bi-phasically altered activity, and increased temperature in male and female rats. Inhalation of heroin 50 mg/mL for 15 min produced significant effects, as the lower bound on efficacy, whereas inhalation of heroin 100 mg/mL for 30 min produced robust effects across all endpoints and groups.

CONCLUSIONS

This work shows that e-cigarette devices deliver psychoactive doses of heroin to rats, using concentrations of ∼50-100 mg/mL and inhalation durations of 15-30 min. This technique may be useful to assess the health consequences of inhaled heroin and other opioid drugs.

An Atypical Presentation of Heroin Inhalation Induced Leukoencephalopathy (Chasing the Dragon)

Heroin leukoencephalopathy is associated with 'Chasing the dragon,' which is a heroin vapour inhalation method that is different from smoking or sniffing heroin. The clinical presentation ranges from mild to severe disease. Mild disease is characterized by inattentiveness and ataxia. In moderate diseases, extrapyramidal symptoms predominate, and finally, severe disease is characterized by generalized motor impairment, with death occurring in two-third of cases. We now report a rare presentation of the disease in a 60-year-old female with a past medical history of heroin abuse who presented to ED with signs and symptoms of confusion and restlessness. MRI brain without contrast showed diffuse symmetric increased intensity signals throughout the white matter. Electroencephalogram (EEG) revealed mild diffuse slowing with no lateralization. The patient was started on Vitamin E and was transferred to a rehab facility with following up neurology as an outpatient.

Demand for fentanyl becomes inelastic following extended access to fentanyl vapor self-administration

Opioid use disorder imposes great societal harm in the United States and in countries worldwide. Animal models that accurately capture motivational changes that occur in opioid dependence are critical to studying this disorder. The present study used a model of opioid vapor self-administration combined with a behavioral economics approach to determine whether rats would be more motivated to "work" to defend their baseline intake of fentanyl (i.e., more inelastic demand) following sufficiently frequent, intense, and chronic exposure to self-administered vaporized fentanyl. Male rats were allowed to respond for deliveries of 1.5-s of vaporized 10 mg/ml fentanyl solution. Following 15 sessions of short access (ShA; 1 h) vs. long access (LgA; 12 h) to self-administration, we conducted a between-sessions demand curve procedure, and observed significantly more inelastic demand for fentanyl (Essential Value; EV), and increased maximal response output (O_max) in LgA compared with ShA rats. In a subsequent phase, the unit-dose was doubled to 3 s of fentanyl vaporization. After seven ShA vs. LgA sessions, we assessed demand again and found that LgA rats, contrasted to ShA rats, demonstrated significantly higher baseline intake or "hedonic setpoint" (Q₀), in addition to significantly increased EV and O_max. These results demonstrate that extended access to self-administration of a vaporized opioid causes changes in behavioral economic metrics consistent with development of an addiction-like state in rats. The combination of the vapor model with a translationally relevant behavioral economics framework opens new avenues to study dysregulated motivational processes in substance use disorders.

Mimicking a Psychiatric Disorder: Heroin-Induced Leukoencephalopathy

Toxic leukoencephalopathy is a rare cause of encephalopathy. We describe two cases of toxic leukoencephalopathy associated with opiate abuse where they were misdiagnosed and admitted to the psychiatric ward. In our case series, both patients presented with behavioral changes, restlessness, pressured speech, and cognitive impairment for which they were initially labeled as psychiatric patients and were treated as such. However, after an extensive workup to elucidate the etiology of alteration in mental status, toxic leukoencephalopathy associated with heroin abuse was found to be the culprit in both cases. Toxic leukoencephalopathy is a rare condition that can be caused by inhalation of heroin. Clinically, it may present with confusion, behavioral changes, extrapyramidal symptoms, generalized motor deficit, unresponsiveness and even death. Our cases highlight the importance of recognizing the psychiatric presentation of toxic leukoencephalopathy.

Bilateral middle cerebellar peduncle lesions: Neuroimaging features and differential diagnoses

OBJECTIVES

Lesions limited to the bilateral middle cerebellar peduncles (MCPs) are uncommon. This retrospective study investigated diseases with a proclivity for the bilateral MCPs and explored the associations between their neuroimaging features and clinical findings for the differential diagnosis of such lesions.

METHODS

We enrolled 26 patients who were admitted to our department between January 2016 and March 2019 with bilateral MCP abnormalities on magnetic resonance imaging (MRI). The demographic, clinical, and neuroimaging characteristics, and the biomarkers and diagnoses were evaluated.

RESULTS

Although all patients exhibited symmetrical bilateral MCP hypointensities on T1-weighted imaging and hyperintensities on T2-weighted and fluid-attenuated inversion recovery imaging, they were diagnosed with different conditions. Diagnoses included acute cerebral infarction (ACI) (n = 9, 34.62%), Wallerian degeneration (WD) (n = 8, 30.77%), multiple system atrophy (MSA) (n = 6, 23.08%), neuromyelitis optica (NMO) (n = 1, 3.85%), heroin-induced leukoencephalopathy (n = 1, 3.85%), and primary central nervous system lymphoma (PCNSL) (n = 1, 3.85%). Patients with ACI exhibited bilateral MCP-restricted diffusion hyperintensities on diffusion-weighted imaging and corresponding stenosis or occlusion of the vertebrobasilar system. The initial MRI of patients with WD depicted pontine infarctions, while symmetrical MCP lesions were observed on follow-up MRI. Symmetrical MCP lesions, cruciform hyperintensity, and marked atrophy in the posterior fossa were characteristic manifestations of MSA. Longitudinally extensive myelitis affecting more than three vertebral segments on cervical MRI and positive serum AQP4-IgG may be indicative of NMO. Heroin-induced leukoencephalopathy was characterized by extra-symmetrical lesions in the posterior limbs of the internal capsules, while the anterior limbs were spared. PCNSL was indicated by a significant and characteristic "fist" sign on contrast-enhanced MRI.

CONCLUSIONS

Bilateral MCP lesions were most frequently observed in cerebrovascular diseases, followed by neurodegenerative diseases, inflammatory diseases, toxic encephalopathies, and lymphomas. Our findings demonstrate that bilateral MCP signal abnormalities are more common in patients with ACI and WD, with fewer degenerative processes than previously believed. The high frequency of WD may be attributed to the specific awareness of this pathology. WD can also present with stage-related restricted diffusion and should not be mistaken for a new infarction. The symmetrical bilateral MCP hypointensities on T1-weighted imaging and hyperintensities on T2-weighted imaging often raise concern regarding a demyelinating process. Our findings emphasize that neurologists should consider the aforementioned conditions and correlate the specific neuroimaging characteristics and medical history before arriving at the final diagnosis.

DARK Classics in Chemical Neuroscience: Heroin and Desomorphine

Opioids are arguably one of the most important pharmacologic classes, mainly due to their rich history, their useful and potent analgesic effects, and also, just as importantly, their "Dark Side", constituted by their reinforcing properties that have led countless of users to a spiral of addiction, biological dependence, tolerance, withdrawal syndromes, and death. Among the most significant abused and addictive known opioids are heroin and desomorphine, both synthetic derivatives of morphine that belong to the 4,5-epoxymorphinan structural chemical group of the opioid family drugs. These agents share not only structural, pharmacological, and epidemiological features but also a common geographical distribution. A drop in Afghan heroin production and its "exports" to Russia gave rise to widespread consumption of desomorphine in ex-Soviet republics during the first decade of the 21st century, representing an economical and accessible alternative for misusers to this sort of derivative. Herein we review the state of the art of history, chemistry and synthesis, pharmacology, and impact on society of these "cursed cousins".

Smoking heroin with cannabis versus injecting heroin: unexpected impact on treatment outcomes

Background

In several countries, especially in Africa, the dominant method of heroin intake is smoking a joint of cannabis laced with heroin. There is no data exploring the impact of smoking heroin with cannabis on treatment outcomes.

Aim

To compare treatment outcomes between people who inject heroin and people who smoke heroin with cannabis.

Methodology

Three hundred heroin users were assessed on admission to inpatient rehabilitation and after treatment. We compared drug use, psychopathology, criminality, social functioning and general health between heroin injectors and heroin-cannabis smokers at treatment entry, and at 3 and 9 months after rehabilitation.

Results

The sample comprised 211 (70.3%) heroin-cannabis smokers and 89 (29.7%) heroin injectors. Eighty-four percent were followed up at 3 months and 75% at 9 months. At 9 months, heroin-cannabis smokers had a higher proportion of those who relapsed to heroin use compared with intravenous (IV) users (p = 0.036). The median number of heroin use episodes per day was lower for IV users than heroin-cannabis smokers at both follow-up points (p = 0.013 and 0.0019). A higher proportion of IV users was HIV positive (p = 0.002). There were no significant differences in psychopathology, general health, criminality and social functioning between IV users and heroin-cannabis smokers at all three time points.

Conclusions

Heroin users who do not inject drugs but use other routes of administration may have increased risk for relapse to heroin use after inpatient rehabilitation and should therefore have equal access to harm reduction treatment services. Advocating a transition from injecting to smoking heroin in an African context may pose unique challenges.

Toxic Leukoencephalopathy Presenting as Lethal Catatonia

INTRODUCTION

Catatonia is a syndrome that can present in different forms and can occur in multiple psychiatric and somatic conditions. This case report describes lethal catatonia caused by delayed toxic leukoencephalopathy after excessive use of cocaine and methadone. The characteristic radiographic imaging and biphasic course are discussed.

CASE REPORT

A 54-year-old woman was presented unconsciously at the emergency department after intoxication with methadone and cocaine. After initial recovery, her condition deteriorated unexpectedly, resulting in lethal catatonia. Magnetic resonance imaging (MRI) showed hyperintense white matter abnormalities and diffusion restriction, evident for leukoencephalopathy.

DISCUSSION

Catatonia can develop in multiple psychiatric and somatic diseases, including toxic leukoencephalopathy. A biphasic course and specific MRI findings are characteristics for delayed toxic leukoencephalopathy, due to intoxication with drugs.