Bilateral acute necrosis of the globi pallidi and rhabdomyolysis due to combined methadone and benzodiazepine toxicity

Intoxications involving methoxyacetylfentanyl and U-47700: a study of 3 polydrug fatalities

Novel synthetic opioids (NSOs) represent an emerging group of novel psychoactive substances, acting as agonists at the opioid receptors. NSOs include fentanyl-related compounds, e.g. methoxyacetylfentanyl (MeACF), and non-fentanyl analogs, e.g. "U compounds" including U-47700. Here we present three cases of death involving MeACF and U-47700, with particular reference to preliminary data on pharmacokinetics and tissue distribution.After a complete post-mortem examination, general unknown screenings and analysis of drugs of abuse were performed on postmortem samples by immunoassays, gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. To quantify the analytes of interest in post-mortem blood and tissues, the standard addition method was used. A toxicological significance score (TSS), weighing the role of the NSO in each death case, was assigned.Case 1 died at the hospital after consumption of U-47700, methadone (serum levels: 2,600 ng/ml and 37 ng/ml), tilidine and benzodiazepines. In case 2, U-47700 (204 ng/ml) together with methadone (290 ng/ml), flubromazepam (480 ng/ml) and diazepam (300 ng/ml) were detected in peripheral blood. In case 3, methoxyacetylfentanyl (266 ng/ml), furanylfentanyl (4.3 ng/ml) 4-ANPP (15 ng/ml) and alprazolam (69 ng/ml) were quantified in femoral blood. In all cases, the NSO likely contributed to the death (TSS = 3).NSOs appear to be often consumed in the setting of polydrug intoxications, especially in combination with other opioids and benzodiazepines, which often exert synergistic effects. The standard addition method remains the most reliable in post-mortem analysis and toxicological results should always be evaluated together with circumstantial and autopsy data.

Neurological Manifestations of Chronic Methadone Maintenance Therapy: A Case Report and Literature Review

Methadone is a long-acting opioid medication that is used as maintenance therapy for heroin addiction. We present a case of a patient on methadone maintenance therapy for chronic back pain who developed neurological complications. The patient presented with mental status changes and choreiform movements. Workup revealed lesions involving the subcortical white matter and basal ganglia. Choreiform movements improved after the initiation of treatment with topiramate, clonazepam, and risperidone. This combination was chosen as several prior case reports published significant benefit and improvement in choreiform movements with the mentioned regimen.

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.

Lesson of the month: Oxycodone-induced leukoencephalopathy: a rare diagnosis

Oxycodone-induced leukoencephalopathy is a rare diagnosis that should be considered in unconscious patients with appropriate history. We describe a case of a 57-year-old unconscious woman who required intubation and did not respond to naloxone infusion. The unconsciousness was initially thought to be due to hypoxic brain injury. However, a further review of brain imaging showed characteristic features of oxycodone-induced leukoencephalopathy. We describe the pathological and radiological features of this condition, and provide a concise review of the limited literature on this condition. Accurate diagnosis of this condition will be valuable to clinicians and patients in terms of their medium-term and long-term prognosis, and potential for rehabilitation.

Differences in cue-induced brain activation between long-term methadone maintenance treatment and protracted abstinence in heroin use disorder patients: a functional magnetic resonance imaging study

Background

Heroin use disorder (HUD) remains one of the gravest public health issues in China. Methadone maintenance treatment (MMT) and protracted abstinence (PA) are the most commonly used treatments for HUD. Although both treatment approaches can alleviate heroin cravings, a previous study found that MMT patients had stronger cue-induced brain activation than patients undergoing PA; however, the changes associated with long-term treatment are unclear.

Methods

Male patients with HUD who had been undergoing either PA (n=24) or MTT (n=21) for approximately 12 months, together with 20 demographically matched healthy controls, completed an event-related functional magnetic resonance imaging (fMRI) task. The subjective craving for heroin was evaluated using a visual analog scale.

Results

Compared to the healthy controls, the MMT and PA groups demonstrated significantly higher brain activation in the left pallidum, middle occipital gyrus, postcentral gyrus, anterior cingulate cortex, middle cingulate cortex, inferior parietal lobule, superior parietal lobule, amygdala, hippocampus, right inferior temporal gyrus, inferior frontal gyrus triangularis, and caudate during exposure to heroin-related cues. Compared to those undergoing PA, patients in the MMT group demonstrated significantly higher brain activation in all of these regions. Except for the left inferior parietal lobule and left superior parietal lobule, there were no statistically significant differences between the PA and healthy control groups. The MMT patients showed significantly higher subjective cravings before and after exposure to heroin cues than the PA group, but there was no significant difference in the change in subjective cravings between the 2 groups.

Conclusions

The results suggested that although the HUD patients receiving long-term MMT complied with the treatment, they still had higher subjective cravings and cue-induced brain activation than those undergoing PA. Therefore, long-term PA appears to be more beneficial than MMT in reducing the salience value of drug cues in patients with HUD.

Bilateral Basal Ganglia Lesions in Patients with Heroin Overdose: A Report of Two Cases

The prevalence of opioid use has increased worldwide. Two-thirds of deaths caused by drug overdose are opioid-related. Individuals with opioid use may present with a variety of complications. The available history in unconscious patients is often insufficient, which may cause diagnostic difficulty and delayed management. We present two cases of 54-year-old and 25-year-old male patients who were brought to our emergency department after being found unconscious at home, without any known preceding event. They were in a deep coma with a Glasgow coma score of 3/15. However, their brainstem reflexes were normal. Pinpoint pupils were observed bilaterally. Brain computed tomography (CT) demonstrated the presence of bilateral basal ganglia hypodensities in both patients, in addition to multiple hypodensities scattered in the cerebral hemispheres of one patient. Toxicology screening from both patients was positive for opioids. The patients were transferred to the intensive care unit for supportive management. One patient recovered completely, whereas the other remained in a vegetative state. The presence of bilateral basal ganglia lesions in brain CT in unconscious patients should alert the physician of opioid use disorder among these patients.

Methadone associated long term hearing loss and nephrotoxicity; a case report and literature review

Background

Methadone is a long-acting opioid receptor agonist. Reported adverse effects of methadone include constipation, respiratory depression, dizziness, nausea, vomiting, itching, sweating, rhabdomyolysis, QT prolongation, and orthostatic hypotension. Hearing loss has been rarely reported following methadone use, and when reported, long term follow-up is rare.

Herein we report a case of methadone poisoning with rhabdomyolysis, acute kidney injury, and persistent hearing loss documented by a 2 year follow up.

Case presentation

The patient was a 34 years old male who presented with a reduced level of consciousness and acute hearing loss after suicidal ingestion of 40 mg of methadone while experiencing family-related stresses. He had no prior history of methadone use, abuse, or addiction.

Initial laboratory testing was significant for a serum creatinine concentration of 4.1 mg/dl, a mixed metabolic and respiratory acidosis, thrombocytopenia, abnormal hepatic transaminases, and coagulation tests. The patient then developed severe rhabdomyolysis. Also, audiometry showed a bilateral sensorineural hearing loss. The patient required hemodialysis for 11 days while his metabolic abnormalities gradually resolved. However, his hearing loss was persistent, as demonstrated by 2 years of follow up.

Conclusion

Our patient simultaneously had kidney failure, rhabdomyolysis, and permanent hearing loss following methadone poisoning. Although rare, ototoxicity and permanent hearing loss may happen in cases of methadone poisoning. While opioid-induced hearing loss is uncommon, methadone toxicity should be taken into account for any previously healthy patient presenting with acute hearing loss with or without rhabdomyolysis.

Methadone-Related Delirium: Prevalence, Causes, and Outcomes

Goals consist of determining 5-year prevalence and recurrence of methadone-related delirium (MRD), along with causes, treatments, and outcomes. Sample comprised 81 patients in methadone maintenance treatment. Criteria for MRD encompassed delirium with high methadone serum levels plus alleviation of delirium upon lowering methadone serum levels. MRD occurred in 14 cases who had 25 episodes. MRD precipitants included physician prescribing (i.e., excessive methadone or medications slowing methadone metabolism), drug misuse, and renal-fluid alterations. Social affiliation (housing with family, intimate partner) reduced MRD; employment increased MRD. Recovery occurred in 23/25 episodes of MRD; two episodes progressed to dementia. Obtaining serum methadone levels fostered prompt recognition.

Delay-Dependent Impairments in Memory and Motor Functions After Acute Methadone Overdose in Rats

Methadone is used as a substitution drug for the treatment of opioid dependence and chronic pain. Despite its widespread use and availability, there is a serious concern with respect to the relative safety of methadone. The purpose of this study was to characterize how acute methadone overdose affects the cognitive and motor performance of naïve healthy rats. The methadone overdose was induced by administering an acute toxic dose of methadone (15 mg/kg; ip; the equivalent dose of 80% of LD50) to adolescent rats. Resuscitation using a ventilator pump along with a single dose of naloxone (2 mg/kg; ip) was administered following the occurrence of apnea. The animals which were successfully resuscitated divided randomly into three apnea groups that evaluated either on day 1, 5, or 10 post-resuscitation (M/N-Day 1, M/N-Day 5, and M/N-Day 10 groups) in the Y-maze and novel object memory recognition tasks as well as pole and rotarod tests. The data revealed that a single toxic dose of methadone had an adverse effect on spontaneous behavior. In addition, Recognition memory impairment was observed in the M/N-Day 1, 5, and 10 groups after methadone-induced apnea. Further, descending time in the M/N-Day 5 group increased significantly in comparison with its respective Saline control group. The overall results indicate that acute methadone-overdose-induced apnea produced delay-dependent cognitive and motor impairment. We suggest that methadone poisoning should be considered as a possible cause of delayed neurological disorders, which might be transient, in some types of memory or motor performance in naïve healthy rats.

Systematic review of nephrotoxicity of drugs of abuse, 2005-2016

BACKGROUND

The United States is faced with an unprecedented epidemic of drug abuse. Every year thousands of Americans visit the emergency departments all over the country with illicit drug related complaints. These drugs have been known to be associated with a range of renal pathologies, from reversible acute kidney injuries to debilitating irreversible conditions like renal infarction. So far, no comprehensive study or systematic review has been published that includes the commonly used street drugs and designer drugs with potential nephrotoxic outcomes.

METHODS

We conducted a systematic review of published case reports, case series, and cross sectional studies of nephrotoxicities related to drugs of abuse. Literature review was conducted using PubMed/Medline from January 1, 2005 -December 31, 2016 to search for publications related to drug abuse with a defined renal outcome. Publications which reported renal injury in relation to the use of illicit drugs were selected, specifically those cases with raised creatinine levels, clinically symptomatic patients, for instance those with oliguria and proven renal biopsies.

RESULTS

A total of 4798 publications were reviewed during the search process and PRISMA flow chart and Moose protocol regarding systematic reviews were followed. 110 articles were shortlisted for the review. A total of 169 cases from case reports and case series, and 14 case studies were analyzed. Renal manifestations of specific illicit drug abuse were included in this review.

CONCLUSION

Based on the evidence presented, a wide range of renal manifestations were found to be associated with drug abuse. If the trend of increasing use of illicit drug use continues, it will put a significant percentage of the population at an elevated risk for poor renal outcomes. This study is limited by the nature of the literature reviewed being primarily case reports and case series.

Methadone for Fun Sake… Kidneys Are at Stake!!!

Acute renal failure from rhabdomyolysis is a well-established clinical entity; however, rhabdomyolysis exclusively caused by the ingestion of methadone requiring hemodialysis is very uncommon. With a similar mechanism to opiates, methadone can cause rhabdomyolysis and further consequences. Given the increasing use of methadone as a therapy for opiate dependence, clinicians prescribing this medication should be aware of this life-threatening complication.

Amnesia Associated with Bilateral Hippocampal and Bilateral Basal Ganglia Lesions in Anoxia with Stimulant Use

We report a case of a 55-year-old man with ischemic lesions of the bilateral hippocampus and bilateral basal ganglia following a myocardial infarction during an episode of multiple drug use with subsequent anoxia requiring resuscitation. He presented for a neuropsychological evaluation with an anterograde amnesia for both explicit and procedural memory. There are two main points to this case, the unique aspects of the bilateral multifocal lesions and the functional, cognitive impact of these lesions. We hypothesize that his rare focal bilateral lesions of both the hippocampus and basal ganglia are a result of anoxia acting in synergy with his stimulant drug use (cocaine and/or 3,4-methylenedioxy-methamphetamine). Second, his unique lesions produced an explicit and implicit/procedural anterograde amnesia.

Methadone-induced Damage to White Matter Integrity in Methadone Maintenance Patients: A Longitudinal Self-control DTI Study

Methadone maintenance treatment (MMT) can induce impairments in brain function and structure, despite its clinical effectiveness. However, the effect of chronic MMT on brain white matter (WM) is not fully known. Thirty-three MMT patients underwent diffusion tensor imaging (DTI) twice – at the start of the study (Scan₁) and one year later (Scan₂). Tract-based spatial statistics were used to investigate changes in fractional anisotropy (FA), axial diffusivity (AD) and radial diffusivity (RD) between the two scans. The correlations between DTI indices and methadone consumption and neuropsychological status were analysed. We found significantly decreased FA, decreased AD and increased RD in Scan₂ in extensive WM regions; overlapping regions were found in the left posterior limb and the retrolenticular part of internal capsule, superior and posterior corona radiata, bilateral external capsule and the right superior longitudinal fasciculus. In addition, the change of FA in the overlapping regions was positively correlated with the accumulated dosage of methadone use, the RD value in Scan₂ and non-planning impulsiveness (NPI) measured at follow-up. The results suggest that methadone has damaging effects on WM integrity. The dose-dependent pattern and characteristics of the impairment may suggest new strategies for MMT.

Delayed-onset movement disorder and encephalopathy after oxycodone ingestion

We present the case of a 14-year-old girl with a biphasic course after oxycodone ingestion. Clinically, she had a rapid return to baseline after initial ingestion and presented a week later with new-onset ballism, akathisia, and encephalopathy. Neuroimaging demonstrated bilateral globi pallidi and cerebellar lesions with a relative decrease of metabolite peaks on magnetic resonance spectroscopy. Her movement disorder was treated successfully with valproic acid and clonidine. Her cognitive functioning returned to baseline 3 months after ingestion.

Naltrexone: a review of existing sustained drug delivery systems and emerging nano-based systems

Narcotic antagonists such as naltrexone (NTX) have shown some efficiency in the treatment of both opiate addiction and alcohol dependence. A few review articles have focused on clinical findings and pharmacogenetics of NTX, advantages and limitations of sustained release systems as well as pharmacological studies of NTX depot formulations for the treatment of alcohol and opioid dependency. To date, three NTX implant systems have been developed and tested in humans. In this review, we summarize the latest clinical data on commercially available injectable and implantable NTX-sustained release systems and discuss their safety and tolerability aspects. Emphasis is also laid on recent developments in the area of nanodrug delivery such as NTX-loaded micelles and nanogels as well as related research avenues. Due to their ability to increase the therapeutic index and to improve the selectivity of drugs (targeted delivery), nanodrug delivery systems are considered as promising sustainable drug carriers for NTX in addressing opiate and alcohol dependence.