Substance abuse and the kidney

When Can Physicians Fire Patients with Opioid Use Disorder for Nonmedical Use of Prescription Medications?

AbstractThe opioid crisis has greatly increased the number of patients who are illegally injecting drugs while hospitalized for other conditions. Physicians face a difficult decision in these circumstances: when is it appropriate to involuntarily discharge or "fire" a patient with opioid use disorder for their continued nonmedical use of opioids? This commentary on a case analyzes physicians' responsibilities to their patients and argues that physicians should fire nonadherent patients only when every other option has been exhausted and the expected benefits of firing the patient outweigh the expected harms.

Caring for Our Patients With Opioid Use Disorder in the Perioperative Period: A Guide for the Anesthesiologist

Opioid use disorder (OUD) is a rising public health crisis, impacting millions of individuals and families worldwide. Anesthesiologists can play a key role in improving morbidity and mortality around the time of surgery by informing perioperative teams and guiding evidence-based care and access to life-saving treatment for patients with active OUD or in recovery. This article serves as an educational resource for the anesthesiologist caring for patients with OUD and is the second in a series of articles published in Anesthesia & Analgesia on the anesthetic and analgesic management of patients with substance use disorders. The article is divided into 4 sections: (1) background to OUD, treatment principles, and the anesthesiologist; (2) perioperative considerations for patients prescribed medications for OUD (MOUD); (3) perioperative considerations for patients with active, untreated OUD; and (4) nonopioid and nonpharmacologic principles of multimodal perioperative pain management for patients with untreated, active OUD, or in recovery. The article concludes with a stepwise approach for the anesthesiologist to support OUD treatment and recovery. The anesthesiologist is an important leader of the perioperative team to promote these suggested best practices and help save lives.

Military service and risk of subsequent drug use disorders among Swedish men

PURPOSE

Environmental factors contribute substantially to risk for drug use disorders (DUD). The current study applies multiple methods to empirically test whether military service is associated with subsequent DUD, as previous findings are inconsistent.

METHODS

Longitudinal Swedish national registry data on a cohort of male conscripts born 1972-1987 (maximum N = 485,900) were used to test the association between military service and subsequent registration for DUD. Cox proportional hazard models were used in preliminary analyses, followed by three methods that enable causal inference: propensity score models, co-relative models, and instrumental variable analysis.

RESULTS

Across all methods, military service was causally associated with lower risk of DUD. Hazard ratios ranged from HR = 0.43 (95% confidence intervals [CI] 0.37; 0.50) in the instrumental variable analysis to 0.77 (0.75; 0.79) in the multivariate propensity score matching analysis. This effect diminished across time. In the model including a propensity score, HRs remained below 1 across the observation period, while confidence intervals included 1 after ~ 11 years in the co-relative analysis and after ~ 21 years in the instrumental variable analysis.

CONCLUSIONS

In this cohort of Swedish men, complementary methods indicate that military service conferred substantial but time-limited protection against subsequent DUD. The observed effect could be due to reduced opportunity for substance use during service, social cohesion experienced during and after service, and/or socioeconomic advantages among veterans. Additional research is necessary to clarify these protective mechanisms and determine how other environmental contexts can provide similar benefits.

Behavioral, biochemical and histopathological toxic profiles induced by sub-chronic cannabimimetic WIN55, 212-2 administration in mice

WIN55, 212-2 mesylate is a synthetic cannabinoid (SC) agonist of CB1 and CB2 receptors with much higher affinity to CB1 receptor than tetrahydrocannabinol and many potential therapeutic effects. Few studies have evaluated SCs effects on more complex animal behavior and sex differences in cannabinoids toxicology. The current study was undertaken for determination of behavioral (Open Field test), biochemical (liver and kidney function test plus GABA & Glutamate levels), histopathological and CB1 immunohistochemistry risks of sub-chronic administration of SC WIN55, 212-2 mesylate in male and female mice. A total of 40 healthy adult mice were randomly divided into four groups (5 mice each): a negative control group, a vehicle group, a low dose (0.05 mg/kg) group and a high dose group (0.1 mg/kg) for each gender.Open Field Test revealed dose and gender-dependent anxiogenic effect with reduced locomotor activity in both sexes especially the higher doses with female mice being less compromised. GABA and glutamate levels increased significantly in both dose groups compared to controls alongside female mice versus males. No significant biochemical alterations were found in all groups with minimal histopathological changes. The CB1 receptors immunohistochemistry revealed a significant increase in the number of CB1 positive neurons in both low and high dose groups against controls with higher expression in female brains.ConclusionsThere were sexual dimorphism effects induced by sub-chronic exposure to WIN55, 212-2 with lesser female mice affection and dose-dependent influences.

Risk of dialysis and renal diseases in patients with anorexia nervosa in Taiwan

OBJECTIVE

To investigate the incidence and risk of renal-related complications in a nationwide cohort of Taiwanese patients with anorexia nervosa (AN).

METHOD

This longitudinal cohort study analyzed the data of 43,951 individuals-comprising 2091 patients with AN and their controls matched (1:20) using propensity scores according to sex, age, degree of urbanization of residence, socioeconomic status, and year of diagnosis-from a population-based health insurance database; the study lasted 16 years. We used Kaplan-Meier curves to estimate the cumulative incidence of renal events. We also performed Cox proportional regression and constructed a risk model with death as a competing event (both adjusted for basic characteristics, renal diseases, and psychiatric comorbidities) to examine the risk of dialysis and renal outcomes in the AN group relative to the control group.

RESULTS

In total, 204 and 10 patients with AN had renal-related outcomes and end-stage renal disease (ESRD), respectively. The cumulative incidence rates of all renal outcomes and ESRD in the AN group were 10.72% and .64%, respectively, at 10-year follow-up. Compared with the control group, the AN group had a significantly higher risk of acute dialysis (adjusted hazard ratio 2.10 [95% confidence interval 1.19-3.68]), hypokalemia, hypovolemia, nephritis, acute renal failure, and chronic renal failure. The AN group did not have a significantly higher risk of ESRD.

DISCUSSION

The elevated risks of acute dialysis and some renal outcomes in AN highlight the importance of monitoring electrolyte imbalance and renal malfunctioning.

PUBLIC SIGNIFICANCE

Malnutrition and purging behaviors may cause renal complications in patients with AN. In this longitudinal cohort study, we found that the 10-year cumulative incidence of all renal outcomes in AN was 10.72%, and that patients with AN had a two-fold higher risk of overall renal outcomes compared with those without AN. Our findings imply that weight restoration and ceasing purging behaviors are crucial for recovery from AN.

Alcohol, nicotine, and COVID-19: A retrospective study of health outcomes in central Pennsylvania

Individuals with substance abuse disorder are at increased risk for the development of severe disease following COVID-19 infection. Furthermore, individuals in rural populations where access to healthcare is limited and rates of substance abuse tend to be higher are at increased risk compared to other regions. The Penn State Health Network serves 29 counties in central Pennsylvania that are largely rural. The current study assessed the electronic medical records for individuals in this population that were reported as having alcohol dependence, nicotine dependence or both (co-users) in addition to individuals with no history of drug use and the rate of developing primary and secondary health outcomes following COVID-19 infection. All patients in this study were determined to be COVID+ while in care. We found that overall, risk for requiring ventilation, developing pneumonia, and mortality within 30 days of diagnosis all increased with any substance use history, across both males and females and across all age groups. Moreover, rates of these outcomes were considerably higher in patients that were both alcohol and nicotine dependent suggesting additive effects of co-use. Rates of secondary effects also increased substantially across all use categories with these patients showing greater risk of developing liver, kidney, and pancreas maladies compared to patients with no history of substance use. Taken together, these findings reinforce previous studies showing that substance use increases the risks of significant disease following COVID-19 infection, giving insights into the health disparities that exist in rural populations.

Effects of Diazepam on Hematological and Histological Parameters in Rats / in Vivo and Unbiased Stereological Investigation

Diazepam-based drugs are widely used today in human treatment. Diazepam may be a primary drug aimed at treating neurological diseases or an associated drug in the treatment of other diseases in the purpose of symptomatic therapy. The sedative effect of diazepam characterizes it as a drug that people usually use on their own and without a doctor’s supervision. Directly, but also through influencing the nervous system, diazepam disrupts proper functioning of all body organs. The purpose of this paper was to examine the effects of diazepam on blood and cytohistological parameters of rats in an in vivo experiment. Mallory-Azan and immunochistochemical staining methods BLX-CX and Survivin tissues of liver, kidney and spleen of rats were used to achieve the set goal. Cytometric analysis of rats detected cells in apoptosis and measurements of stereological parameters were made using a system according to Cavalier’s principle. Results of analysis of hematological and histological parameters indicate a detrimental effect of diazepam on blood parameters, as well as on structure and functioning of the liver, kidneys and spleen of rats. This paper is a foundation for further detailed scientific research with the aim of elucidating all harmful effects that diazepam has on all organs in the body of rats. This data could serve as a starting point for future studies in clinical pharmacology on therapeutic protocols for usage of diazepam-based sedatives.

Substance use among adolescents and young adults with chronic kidney disease or kidney failure

Substance use, a significant public health issue, is well described in the adult chronic kidney disease (CKD) population. Knowledge about substance use in the adolescent and young adult (AYA) CKD population such as prevalence, impact on kidney function, medication adherence, and psychosocial well-being remain largely unknown. Awareness of and inquiring about substance use is paramount to providing evidence-based care and preparation to transition to adult-focused health services. The authors in this review identify commonly used substances (alcohol, tobacco, marijuana, etc.) and how they impact kidney function and care of the AYA with CKD or kidney failure. Recommendations for screening and intervention strategies are provided.

Impact of Chronic Alcohol and Opioid Dependence on Biochemical Parameters: A Retrospective Case Control Study from a Tertiary Care Treatment Center in North India

Background

Assessment of biochemical parameters can help in the comprehensive management of patients with substance use disorders (SUDs). The aim of this study was to analyse the biochemical parameters of patients with alcohol and opioid dependence at an addiction treatment facility.

Methods

This retrospective study analysed the investigation reports of male patients (aged 18 to 70 years) who visited outpatient department (OPD) with primary diagnosis as opioid dependence syndrome (ODS) or alcohol dependence syndrome (ADS). The data included liver function tests (LFTs), kidney function tests (KFTs), and electrolyte tests conducted in the laboratory in a span of one year.

Findings

The study included 713 ADS, 654 ODS, and 227 controls. The ADS group showed significant elevations in mean values of bilirubin, aspartate transaminase (AST), alanine transaminase (ALT), and gamma-glutamyl transferase (GGT) as compared to other groups. A significant decrease in albumin levels in ADS group and raised potassium levels in ODS group was observed. De Ritis ratio above threshold (AST/ALT > 2.0) alone and along with raised GGT levels was observed among 11.3% and 9.7% of patients with ADS, respectively (P < 0.001). Electrolyte abnormalities were present in about 20.0% of patients with ADS and ODS as compared to 8.4% among controls (P < 0.001).

Conclusion

LFT and electrolyte abnormalities are frequently observed in patients with alcohol and opioid dependence. De Ritis ratio along with raised GGT levels significantly denotes ADS group. These results merit attention in the course of clinical care of alcohol and opioid-dependent patients.

Acute kidney damage by PM2.5 exposure in a rat model

PM2.5 exposure is associated with a glomerular filtration rate (GFR) reduction, and renal tissue damage. The goal of this study was demonstrate the acute effect of PM2.5 on the kidney. Male rats were acutely exposed to PM2.5 or filtered air. Blood pressure was mesure and early kidney biomarkers were evaluated in serum and urine samples, and also IL-1β, IL-6 and TNFα were determined. Oxidative biomarkers, angiotensin/bradykinin-related proteins, KIM-1, IL-6 and histology were determined. Blood pressure, GFR, and early kidney damage biomarkers increase together with oxidative biomarkers and angiotensin/bradykinin endocrine-related proteins increased after exposure to PM2.5. Urinary IL-6 increased after exposure to PM2.5, whereas in kidney cortex decreased. Histological changes were observed and accompanied by the induction of KIM-1. Acute exposure to PM2.5 not decline kidney function. However, it can induce early kidney damage biomarkers, oxidative stress, inflammation and angiotensin mediators, which perhabs culminates in a lose of renal function.

Abdominal Imaging Manifestations of Recreational Drug Use

Recreational drug use is a burgeoning health issue worldwide, with a variety of presenting symptoms and complications. These complications can be secondary to the toxic effects of the drug itself, drug impurities, and nonsterile injection. The abdominal radiologist is likely to encounter patients who use drugs recreationally and may be responsible for recognizing and reporting these acute conditions, which in some cases can be life threatening. Because these patients often present with an altered mental state and may deny or withhold information on drug use, the underlying cause may be difficult to determine. The most commonly used drugs worldwide include cocaine, cannabinoids, opioids, and amphetamines and their derivatives. Complications of use of these drugs that can be seen at abdominopelvic CT can involve multiple organ systems, including the soft tissue and gastrointestinal, genitourinary, vascular, and musculoskeletal systems. A diverse range of abdominal complications associated with these drugs can be seen at imaging, including disseminated infections, gastrointestinal ischemia, and visceral infarction. Radiologists should be familiar with the imaging findings of these complications to accurately diagnose these entities and help guide workup and patient treatment. ^©RSNA, 2020.

Repeated Administration of Clinical Doses of Tramadol and Tapentadol Causes Hepato- and Nephrotoxic Effects in Wistar Rats

Tramadol and tapentadol are fully synthetic and extensively used analgesic opioids, presenting enhanced therapeutic and safety profiles as compared with their peers. However, reports of adverse reactions, intoxications and fatalities have been increasing. Information regarding the molecular, biochemical, and histological alterations underlying their toxicological potential is missing, particularly for tapentadol, owing to its more recent market authorization. Considering the paramount importance of liver and kidney for the metabolism and excretion of both opioids, these organs are especially susceptible to toxicological damage. In the present study, we aimed to characterize the putative hepatic and renal deleterious effects of repeated exposure to therapeutic doses of tramadol and tapentadol, using an in vivo animal model. Male Wistar rats were randomly divided into six experimental groups, composed of six animals each, which received daily single intraperitoneal injections of 10, 25 or 50 mg/kg tramadol or tapentadol (a low, standard analgesic dose, an intermediate dose and the maximum recommended daily dose, respectively). An additional control group was injected with normal saline. Following 14 consecutive days of administration, serum, urine and liver and kidney tissue samples were processed for biochemical, metabolic and histological analysis. Repeated administration of therapeutic doses of both opioids led to: (i) increased lipid and protein oxidation in liver and kidney, as well as to decreased total liver antioxidant capacity; (ii) decreased serum albumin, urea, butyrylcholinesterase and complement C3 and C4 levels, denoting liver synthesis impairment; (iii) elevated serum activity of liver enzymes, such as alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and γ-glutamyl transpeptidase, as well as lipid profile alterations, also reflecting hepatobiliary commitment; (iv) derangement of iron metabolism, as shown through increases in serum iron, ferritin, haptoglobin and heme oxygenase-1 levels. In turn, elevated serum cystatin C, decreased urine creatinine output and increased urine microalbumin levels were detected upon exposure to tapentadol only, while increased serum amylase and urine N-acetyl-β-D-glucosaminidase activities were observed for both opioids. Collectively, these results are compatible with kidney injury. Changes were also found in the expression levels of liver- and kidney-specific toxicity biomarker genes, upon exposure to tramadol and tapentadol, correlating well with alterations in lipid profile, iron metabolism and glomerular and tubular function. Histopathological analysis evidenced sinusoidal dilatation, microsteatosis, mononuclear cell infiltrates, glomerular and tubular disorganization, and increased Bowman's spaces. Although some findings are more pronounced upon tapentadol exposure, our study shows that, when compared with acute exposure, prolonged administration of both opioids smooths the differences between their toxicological effects, and that these occur at lower doses within the therapeutic range.

Dopamine D3 receptor-based medication development for the treatment of opioid use disorder: Rationale, progress, and challenges

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Opioid abuse and overdose have become a national crisis in the USA.

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Although several opioid-based pharmacotherapies are available, they are ineffective in long-term relapse prevention.

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National Institute on Drug Abuse has listed dopamine D3 receptor antagonists as high priority for anti-opioid medication development.

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The novel D3 receptor antagonists (VK4-116, VK4-40) are effective in reducing opioid reward and relapse as well as potentiate opioid analgesia.

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D3 receptor antagonists deserve further studies as new pharmacotherapies for pain and of opioid use disorder.

Opioid abuse and related overdose deaths continue to rise in the United States, contributing to the current national opioid crisis. Although several opioid-based pharmacotherapies are available (e.g., methadone, buprenorphine, naloxone), they show limited effectiveness in long-term relapse prevention. In response to the opioid crisis, the National Institute on Drug Abuse proposed a list of pharmacological targets of highest priority for medication development for the treatment of opioid use disorders (OUD). Among these are antagonists of dopamine D3 receptors (D3R). In this review, we first review recent progress in research of the dopamine hypothesis of opioid reward and abuse and then describe the rationale and recent development of D3R ligands for the treatment of OUD. Herein, an emphasis is placed on the effectiveness of newly developed D3R antagonists in the animal models of OUD. These new drug candidates may also potentiate the analgesic effects of clinically used opioids, making them attractive as adjunctive medications for pain management and treatment of OUD.

Candida parapsilosis endocarditis in an intravenous drug abuser: an autopsy report

Candida parapsilosis is a rare cause of endocarditis, which is seen to affect the native valves in patients who are known intravenous drug abusers or following contamination during surgery for prosthetic valves. We discuss a unique constellation of autopsy findings in a 35-year-old chronic opium abuser who presented with left-sided weakness followed by low-grade fever. He was diagnosed to have C. parapsilosis native valve endocarditis with septic emboli involving the myocardial vessels, left middle cerebral artery, spleen, and common iliac artery. In addition, autopsy highlighted a right basal ganglia infarct, focal segmental glomerulonephritis, and talc granulomatosis in the lungs and liver.

Self-Reported Tobacco, Alcohol, and Illicit Drug Use and Progression of Chronic Kidney Disease

BACKGROUND AND OBJECTIVES

Previous studies suggest that tobacco, alcohol, and illicit drug use is associated with CKD. We examined the associations of substance use with CKD progression and all-cause mortality among patients with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Chronic Renal Insufficiency Cohort Study is a prospective, longitudinal cohort study among 3939 participants with CKD in the United States. Self-reported tobacco smoking, alcohol drinking, marijuana use, and hard illicit drug (cocaine, heroin, or methamphetamine) use were obtained at baseline and annual follow-up visits. CKD progression was defined as incident ESKD or halving of eGFR. Substance use was modeled as the cumulative average exposure to capture both recent and long-term use in multivariable time-dependent Cox regression.

RESULTS

Over a median 5.5-year follow-up, 1287 participants developed CKD progression, and 1001 died. Baseline proportions of tobacco smoking, alcohol drinking, marijuana use, and hard illicit drug use were 13%, 20%, 33%, and 12%, respectively. Compared with nonsmoking throughout follow-up, multivariable-adjusted hazard ratios for persistent tobacco smoking were 1.02 (95% confidence interval, 0.86 to 1.21) for CKD progression and 1.86 (95% confidence interval, 1.54 to 2.24) for all-cause mortality. Compared with nondrinking throughout follow-up, multivariable-adjusted hazard ratios for persistent alcohol drinking were 1.06 (95% confidence interval, 0.88 to 1.29) for CKD progression and 0.73 (95% confidence interval, 0.58 to 0.91) for all-cause mortality. Compared with nonuse throughout follow-up, multivariable-adjusted hazard ratios for persistent marijuana use were 0.94 (95% confidence interval, 0.82 to 1.07) for CKD progression and 1.11 (95% confidence interval, 0.96 to 1.30) for all-cause mortality. Compared with nonuse throughout follow-up, multivariable-adjusted hazard ratios for persistent hard illicit drug use were 1.25 (95% confidence interval, 1.00 to 1.55) for CKD progression and 1.41 (95% confidence interval, 1.10 to 1.81) for all-cause mortality.

CONCLUSIONS

Hard illicit drug use is associated with higher risk of CKD progression and all-cause mortality, tobacco smoking is associated with higher risk of all-cause mortality, and alcohol drinking is associated with lower risk of all-cause mortality among patients with CKD.

Pharmacokinetics of Sustained-Release Oral Dexamphetamine Sulfate in Cocaine and Heroin-Dependent Patients

INTRODUCTION

Research has shown that sustained-release (SR) dexamphetamine is a promising agonist treatment for cocaine dependence. However, little is known about the pharmacokinetics (PKs) of SR oral dexamphetamine. This study examined the PKs of a new SR dexamphetamine formulation in cocaine plus heroin-dependent patients currently in heroin-assisted treatment.

METHODS

The study was designed as an open-label PK study in 2 cohorts: n = 5 with once daily 60 mg and n = 7 with once daily 30 mg SR oral dexamphetamine. Five days of blood plasma dexamphetamine concentrations measured with liquid chromatography-mass spectrometry with PK parameter estimates using noncompartmental analysis.

RESULTS

Twelve cocaine-dependent plus heroin-dependent patients in heroin-assisted treatment were included. The initial cohort 1 dose of 60 mg once daily was adjusted to 30 mg after mild to moderate adverse events. After oral administration, tmax values (coefficient of variation %) were 6.0 (17.0%) and 6.3 (16.3%) hours and t1/2 were 11 (24.6%) and 12 (25.4%) hours for 60 mg and 30 mg SR dexamphetamine, respectively. At steady state, CSSmax values were reached at 100 (27.5%) ng/mL and 58.4 (14.4%) ng/mL, whereas CSSmin values were 39.5 (38.9%) ng/mL and 21.8 (19.8%) ng/mL for 60 mg and 30 mg, respectively.

CONCLUSIONS

The investigated SR formulation of dexamphetamine showed favorable slow-release characteristics in cocaine and heroin-dependent patients. A dose-proportional steady-state concentration was achieved within 3 days. These findings support the suitability of the SR formulation in the treatment of cocaine dependence.

Risk characterization of hospitalizations for mental illness and/or behavioral disorders with concurrent heat-related illness

Background

Many studies have found significant associations between high ambient temperatures and increases in heat-related morbidity and mortality. Several studies have demonstrated that increases in heat-related hospitalizations are elevated among individuals with diagnosed mental illnesses and/or behavioral disorders (MBD). However, there are a limited number of studies regarding risk factors associated with specific mental illnesses that contribute, at least in part, to heat-related illnesses (HRI) in the United States.

Objective

To identify and characterize individual and environmental risk factors associated with MBD hospitalizations with a concurrent HRI diagnosis.

Methods

This study uses hospitalization data from the Nationwide Inpatient Sample (2001–2010). Descriptive analyses of primary and secondary diagnoses of MBDs with an HRI were examined. Risk ratios (RR) were calculated from multivariable models to identify risk factors for hospitalizations among patients with mental illnesses and/or behavioral disorders and HRI.

Results

Nondependent alcohol/drug abuse, dementia, and schizophrenia were among the disorders that were associated with increased frequency of HRI hospitalizations among MBD patients. Increased risk of MBD hospitalizations with HRI was observed for Males (RR, 3.06), African Americans (RR, 1.16), Native Americans (RR, 1.70), uninsured (RR, 1.92), and those 40 years and older, compared to MBD hospitalizations alone.

Conclusions

Previous studies outside the U.S. have found that dementia and schizophrenia are significant risk factors for HRI hospitalizations. Our results suggest that hospitalizations among substance abusers may also be an important risk factor associated with heat morbidity. Improved understanding of these relative risks could help inform future public health strategies.

Acute administration of tramadol and tapentadol at effective analgesic and maximum tolerated doses causes hepato- and nephrotoxic effects in Wistar rats

Tramadol and tapentadol are two atypical synthetic opioid analgesics, with monoamine reuptake inhibition properties. Mainly aimed at the treatment of moderate to severe pain, these drugs are extensively prescribed for multiple clinical applications. Along with the increase in their use, there has been an increment in their abuse, and consequently in the reported number of adverse reactions and intoxications. However, little is known about their mechanisms of toxicity. In this study, we have analyzed the in vivo toxicological effects in liver and kidney resulting from an acute exposure of a rodent animal model to both opioids. Male Wistar rats were intraperitoneally administered with 10, 25 and 50mg/kg tramadol and tapentadol, corresponding to a low, effective analgesic dose, an intermediate dose and the maximum recommended daily dose, respectively, for 24h. Toxicological effects were assessed in terms of oxidative stress, biochemical and metabolic parameters and histopathology, using serum and urine samples, liver and kidney homogenates and tissue specimens. The acute exposure to tapentadol caused a dose-dependent increase in protein oxidation in liver and kidney. Additionally, exposure to both opioids led to hepatic commitment, as shown by increased serum lipid levels, decreased urea concentration, increased alanine aminotransferase and decreased butyrylcholinesterase activities. It also led to renal impairment, as reflected by proteinuria and decreased glomerular filtration rate. Histopathological findings included sinusoidal dilatation, microsteatosis, vacuolization, cell infiltrates and cell degeneration, indicating metabolic changes, inflammation and cell damage. In conclusion, a single effective analgesic dose or the maximum recommended daily dose of both opioids leads to hepatotoxicity and nephrotoxicity, with tapentadol inducing comparatively more toxicity. Whether these effects reflect risks during the therapeutic use or human overdoses requires focused attention by the medical community.

Tubulointerstitial Injury and Drugs of Abuse

Drug abuse is widespread in many populations, and patients abusing illicit substances are at a significantly increased risk of kidney injury. The tubulointerstitial compartment is a common target of these nephrotoxic agents. This review will cover some of the common illicit drugs and will focus on the tubulointerstitial injuries seen in the setting of drug abuse. Agents addressed in this review are synthetic cannabinoids, "bath salts," ecstasy, anabolic steroids, inhaled solvents, heroin, and cocaine. The most frequent biopsy findings are those of acute tubular necrosis and acute interstitial nephritis. Unfortunately, histology is often unable to sufficiently narrow the differential diagnosis and point to a single likely cause. A high suspicion for drug abuse as a potential cause of kidney injury is needed to identify the patients for whom this is the cause of their kidney failure. Toxicology screens are often of little use in identifying patients using emerging drugs of abuse.

Non-traumatic rhabdomyolysis: Background, laboratory features, and acute clinical management

Rhabdomyolysis is a relatively rare condition, but its clinical consequences are frequently dramatic in terms of both morbidity and mortality. Although no consensus has been reached so far about the precise definition of this condition, the term rhabdomyolysis describes a rapid breakdown of striated, or skeletal, muscle. It is hence characterized by the rupture and necrosis of muscle fibers, resulting in release of cell degradation products and intracellular elements within the bloodstream and extracellular space. Notably, the percentage of patients with rhabdomyolysis who develop acute kidney injury, the most dramatic consequence, varies from 13% to over 50% according to both the cause and the clinical and organizational setting where they are diagnosed. Despite direct muscle injury (i.e., traumatic rhabdomyolysis) remains the most common cause, additional causes, frequently overlapping, include hypoxic, physical, chemical or biological factors. The conventional triad of symptoms includes muscle pain, weakness and dark urine. The laboratory diagnosis is essentially based on the measurement of biomarkers of muscle injury, being creatine kinase (CK) the biochemical "gold standard" for diagnosis, and myoglobin the "gold standard" for prognostication, especially in patients with non-traumatic rhabdomyolysis. The essential clinical management in the emergency department is based on a targeted intervention to manage the underlying cause, combined with infusion of fluids and eventually sodium bicarbonate. We will present and discuss in this article the pathophysiological and clinical features of non-traumatic rhabdomyolysis, focusing specifically on Emergency Department (ED) management.

Nephrotoxicity of methadone: a systematic review

Background

Methadone is commonly administered for chronic pain relief and treatment of opioid dependence. Concurrent with its increased consumption, toxicities and fatalities have increased. One of the adverse effects of opioid analgesics, including methadone, is that of nephrotoxicity. Opioids can have an effect on renal function through several different mechanisms.

Methods

We searched common bibliographical databases for the terms methadone, toxicity, poisoning, kidney, renal, and nephrotoxicity and summarize our findings in this review.

Results

Methadone can have both direct and indirect effects on the kidney. These effects include rhabdomyolysis (leading to acute kidney injury), volumetric changes, renal lipidosis and amyloidosis, kidney growth during pregnancy, and kidney transplant rejection.

Conclusion

Improved understanding of the effects of methadone on kidney function can promote safer and more confident use of the drug.

Identifying and Addressing the Unmet Health Care Needs of Drug Court Clients

Drug courts address issues such as employment and housing but largely miss the opportunity to address important health care issues. The current study examined the prevalence and correlates of chronic medical conditions among a sample of drug court clients who were participating in a clinical trial of an intervention to reduce HIV risk. A total of 256 clients completed a health survey at entry into the drug court program and 9 months post-entry. The baseline health survey included a comprehensive list of chronic medical conditions, and participants were asked to indicate which, if any, they had ever been diagnosed as having. They were also asked to indicate whether or not they were currently receiving treatment for each chronic condition that they endorsed. The follow-up survey was identical to the baseline survey, with the exception that it contained items reflecting (1) whether or not any member of the drug court team engaged in discussion with the client about each of the chronic conditions reported and (2) whether the client received a referral to medical care for endorsed conditions while in the drug court program. Results indicated that over 50% of clients reported at least one chronic condition and 21% reported more than one condition. Among those with chronic conditions, 71% reported having chronic conditions for which they were not currently receiving treatment. Unfortunately, drug court clients reported that the drug court team did little to address these unmet health needs. Findings from this study suggest that clients could benefit if drug court programs began to widen their focus to include addressing health-related issues.

Insights into Population Health Management Through Disease Diagnoses Networks

The increasing availability of electronic health care records has provided remarkable progress in the field of population health. In particular the identification of disease risk factors has flourished under the surge of available data. Researchers can now access patient data across a broad range of demographics and geographic locations. Utilizing this Big healthcare data researchers have been able to empirically identify specific high-risk conditions found within differing populations. However to date the majority of studies approached the issue from the top down, focusing on the prevalence of specific diseases within a population. Through our work we demonstrate the power of addressing this issue bottom-up by identifying specifically which diseases are higher-risk for a specific population. In this work we demonstrate that network-based analysis can present a foundation to identify pairs of diagnoses that differentiate across population segments. We provide a case study highlighting differences between high and low income individuals in the United States. This work is particularly valuable when addressing population health management within resource-constrained environments such as community health programs where it can be used to provide insight and resource planning into targeted care for the population served.

Mortality and illicit drug dependence among hemodialysis patients in the United States: a retrospective cohort analysis

Background

Illicit drug use is common and known to cause and exacerbate a wide spectrum of kidney disease, often leading to end-stage renal disease (ESRD), but little is known about its prevalence or associated mortality among incident hemodialysis patients.

Methods

This study is a retrospective cohort analysis using data obtained from the United States Renal Data System. We assembled a cohort of 511,821 incident hemodialysis patients age 20 years and older who initiated hemodialysis between January 1, 2006 and December 31, 2010. Illicit drug dependence was defined by comorbidity on the ESRD Medical Evidence Report (Form CMS-2728). We performed survival analysis to examine the association of drug dependence with overall mortality and mortality due to diagnoses that can be associated with intravenous drug use (drug-sensitive diagnoses) in the first year after initiating hemodialysis.

Results

Drug dependence was recorded for 1.5 % (n = 7,461). Drug dependence was independently associated with a 1.3-fold and 2.5-fold higher hazard of overall mortality and mortality due to a potentially drug-sensitive diagnosis [adjusted hazard ratio (AHR) 1.34 (1.27–1.41) and 2.54 (2.05–3.14), p < 0.001, respectively]. This association varied significantly by age (p_interaction < 0.001), with a 9-fold higher hazard of mortality due to a potentially drug-sensitive diagnosis among the youngest patients with drug dependence [AHR 9.21 (5.15–16.44), p < 0.001].

Conclusion

Illicit drug dependence is a burden within the ESRD program and is strongly associated with premature mortality, particularly among younger patients. Targeted intervention is needed to help reduce this burden.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-016-0271-1) contains supplementary material, which is available to authorized users.

Scintigraphic evaluation of renal functional damage in volatile substance abusers

OBJECTIVE

Volatile organic compounds can be maintained easily and can cause dependency. Volatile substance abuse may cause damage by affecting several systems. The aim of our study was to evaluate renal functional damage in volatile substance abusers by diuretic renogram.

METHODS

Twenty nine volatile substance abusers and 30 young healthy voluntary young men were included in our study. Technetium-99m mertiatide diuretic renogram was used to evaluate renal functions and collective system urodynamics to investigate the progress of renal functional damage. Images were evaluated visually and quantitatively. Split renal function of each kidney, time to peak activity (Tmax), and half-time for radiopharmaceutical clearance from pelvicalyceal system (T1/2), ratio of cortical and whole-kidney counts at 20-3 min, and maximum counts (T20/3 and T20/max) were compared in the two groups.

RESULTS

In the study group, time to reach peak activity was statistically prolonged compared with the healthy volunteers. In the volatile substance abuser group, the average Tmax values, average T1/2 values, cortical and whole-kidney T20/3, and T20/max values were found to be prolonged compared with the control group in the diuretic renogram. There was no significant difference in the split renal function ratios between the two groups.

CONCLUSION

In this study, possible renal functional damage was evaluated in volatile substance abusers by diuretic renogram. In conclusion, diuretic renogram can be useful in the evaluation of renal functional damage before blood renal function tests are affected and it could be used in the follow-up of the disease in volatile substance abusers. The results of this pilot study from our country, of course, should be supported by further clinical studies.

The Association Between Stimulant, Opioid, and Multiple Drug Use on Behavioral Health Care Utilization in a Safety-Net Health System

BACKGROUND

Prior studies show an association between drug use and health care utilization. The relationship between specific drug type and emergent/urgent, inpatient, outpatient, and behavioral health care utilization has not been examined. We aimed to determine if multiple drug use was associated with increased utilization of behavioral health care.

METHODS

To assess health care utilization, we conducted a retrospective cohort study of patients who accessed health care at a safety-net medical center and affiliated clinics. Using electronic health records, we categorized patients who used stimulants, opioids, or multiple drugs based on urine toxicology screening tests and/or International Classification of Diseases, 9th Revision (ICD-9). Remaining patients were categorized as patients without identified drug use. Health care utilization by drug use group and visit type was determined using a negative binomial regression model. Associations were reported as incidence rate ratios. Utilization was described by rates of health care-related visits for inpatient, emergent/urgent, outpatient, and behavioral health care among patients who used drugs, categorized by drug types, compared with patients without identified drug use.

RESULTS

Of 95,198 index visits, 4.6% (n=4340) were by patients who used drugs. Opioid and multiple drug users had significantly higher rates of behavioral health care visits than patients without identified drug use (opioid incidence rate ratio [IRR]=7.2; 95% confidence interval [CI]: 3.8-13.8; multiple drug use IRR=5.6, 95% CI: 3.3-9.7). Patients who used stimulants were less likely to use behavioral health services (IRR=1.3, 95% CI: 0.9-2.0) when compared with opioid and multiple drug users, but were more likely to use inpatient (IRR=1.6, 95% CI: 1.4-1.8) and emergent/urgent care (IRR=1.4, 95% CI: 1.3-1.5) services as compared with patients without identified drug use.

CONCLUSIONS

Integrated medical and mental health care and drug treatment may reduce utilization of costly health care services and improve patient outcomes. How to capture and deliver primary care and behavioral health care to patients who use stimulants needs further investigation.

Alcohol and substance abuse in solid-organ transplant recipients

This review focuses on alcohol and substance abuse in the context of solid-organ transplantation. Alcohol and substance abuse are common and may lead to a need for solid-organ transplantation and may also contribute to significant physical and psychologic problems that impact upon the recipient. Damaging levels of alcohol intake can occur in the absence of dependence. Alcohol or substance abuse after transplantation is associated with poor medication compliance and this may increase risk of graft loss. Intravenous drug use is associated with increased risk of infections (especially secondary to opportunistic organisms-bacterial, viral, protozoal, and others-and such infections may be more severe in the immunosuppressed), but there is only anecdotal evidence that such behavior has a worse outcome in transplant recipients. Whereas previous alcohol excess and drug use in kidney recipients are both associated with a small but statistically significantly increased risk of adverse outcomes (hazard ratio, 1.16-1.56), alcohol use within recommended guidelines after transplantation appears safe and possibly beneficial. Robust data are lacking for other organs, but those available suggest that heart transplantation is safe in individuals with a history of alcohol or substance abuse. Health specialists in drug or alcohol addiction should carefully screen all potential transplant candidates for these conditions, and where there is evidence of dependency or abuse, effective psychologic and physical treatment should be offered. Studies have shown that interventions such as psychologic intervention have improved alcohol behavior in the context of liver transplantation. Although there are no comparable studies with other solid-organ recipients, it is reasonable to expect transferable outcomes.

Urological complications of illicit drug use

Illicit drug use is prevalent worldwide; over 24 million people are estimated to have used recreational drugs during the past month in the UK and USA alone. Illicit drug use can result in a wide spectrum of potential medical complications that include many urological manifestations. To ensure optimal care and treatment, urologists need to be cognizant of these complications in their patients, particularly among youths. Ketamine uropathy is thought to affect over one-quarter of ketamine users and can lead to severe lower urinary tract symptoms, as well as upper tract obstruction. Cannabis use has been associated with an increased risk of bladder cancer, prostate cancer and nonseminomatous germ cell tumours in case-control studies. Fournier's gangrene has been reported following injection of heroin and cocaine into the penis. Excessive use of cough medicines can lead to the development of radiolucent stones composed of ephedrine, pseudoephedrine and guaifenesin. As the current evidence is mostly limited to case reports and case series, future epidemiological studies are needed to fully address this issue.

HIV therapy, metabolic and cardiovascular health are associated with glomerular hyperfiltration among men with and without HIV infection

OBJECTIVE

Diabetes and hypertension, common conditions in antiretroviral-treated HIV-infected individuals, are associated with glomerular hyperfiltration, which precedes the onset of proteinuria and accelerated kidney function decline. In the Multicenter AIDS Cohort Study, we examined the extent to which hyperfiltration is present and associated with metabolic, cardiovascular, HIV and treatment risk factors among HIV-infected men.

DESIGN

Cross-sectional cohort using direct measurement of glomerular filtration rate by iohexol plasma clearance for 367 HIV-infected men and 241 HIV-uninfected men who were free of chronic kidney disease.

METHODS

Hyperfiltration was defined as glomerular filtration rate above 140-1 ml/min per 1.73 m per year over age 40. Multivariate logistic regression was used to estimate the odds ratios (ORs) of prevalent hyperfiltration for metabolic, cardiovascular, HIV and cumulative antiretroviral exposure factors.

RESULTS

Among individuals without chronic kidney disease, the prevalence of hyperfiltration was higher for HIV-infected participants (25%) compared to uninfected participants (17%; P = 0.01). After adjustment, HIV infection remained associated with hyperfiltration [OR 1.70, 95% confidence interval (CI) 1.11-2.61] and modified the association between diabetes and hyperfiltration, such that the association among HIV-uninfected men (OR 2.56, 95% CI 1.33-5.54) was not observed among HIV-infected men (OR 1.19, 95% CI 0.69-2.05). These associations were independent of known risk factors for hyperfiltration. Indicators of hyperglycemia and hypertension were also associated with hyperfiltration as was cumulative zidovudine exposure.

CONCLUSION

Hyperfiltration, a potential modifiable predictor of kidney disease progression, is significantly higher among antiretroviral-treated HIV-infected men. Furthermore, HIV-infection nullifies the association of diabetes and hyperfiltration present in HIV-uninfected men.

Medical consequences of marijuana use: a review of current literature

With the advent of legalization of marijuana for medicinal and recreational purposes, and the increase use of marijuana, healthcare providers will be increasingly confronted with marijuana users as patients in clinical environments. While there is vast literature regarding the societal and mental health harms associated with marijuana use, there is a paucity of reviews of the potential consequences of marijuana use on physical health or medical conditions. We examine the recent literature on the physical harms associated with illicit and legal marijuana administration. We surveyed the peer-reviewed medical literature from 1998 to 2013 of studies assessing the association of marijuana use and physical diseases. We conclude that healthcare providers should be cognizant that the existing literature suggests that marijuana use can cause physical harm. However, evidence is needed, and further research should be considered, to prove causal associations of marijuana with many physical health conditions.

Geranylgeranylacetone protects against morphine-induced hepatic and renal damage in mice

The acute or chronic administration of opioid drugs may induce oxidative damage and cellular apoptosis in the liver and kidney, and hence result in hepatic and renal damage. Thioredoxin-1 (Trx-1) and heat shock protein 70 (Hsp70) are emerging as important modulators of cellular functions. They have been shown to be involved in cellular protective mechanisms against a variety of toxic stressors. The present study was designed to investigate the effects of geranylgeranylacetone (GGA), a pharmacological inducer of Trx-1 and Hsp70, on morphine-induced hepatic and renal damage. Morphine induced apoptosis in the liver and kidney through the mitochondria-mediated apoptosis pathway, but not the endoplasmic reticulum-mediated pathway. The activation of caspases-9 and -3 was attenuated by pre‑treatment with GGA. In addition, the morphine-induced increase of malondialdehyde (MDA) levels was suppressed by GGA. Furthermore, GGA enhanced morphine-induced expression of Trx-1 and Hsp70 in the liver and kidney. The findings of this study suggest that GGA may be a safe and novel therapeutic agent for morphine‑induced hepatic and renal damage.

Bath salts: a newly recognized cause of acute kidney injury

Bath salts are substance of abuse that are becoming more common and are difficult to recognize due to negative toxicology screening. Acute kidney injury due to bath salt use has not previously been described. We present the case of a previously healthy male who developed acute kidney injury and dialysis dependence after bath salt ingestion and insufflation. This was self-reported with negative toxicology screening. Clinical course was marked by severe hyperthermia, hyperkalemia, rhabdomyolysis, disseminated intravascular coagulation, oliguria, and sepsis. We discuss signs and symptoms, differential diagnoses, potential mechanisms of injury, management, and review of the literature related to bath salt toxicity.

Reversible minimal change nephrotic syndrome and glomerular IgA deposition associated with nonparenteral heroin abuse: a case report

OBJECTIVE

To report for the first time a case of reversible minimal change nephrotic syndrome with immunoglobulin A (IgA) deposition associated with heroin.

CLINICAL PRESENTATION AND INTERVENTION

A 29-year-old male heroin abuser who developed nephrotic syndrome was admitted to our clinic. Renal biopsy revealed minimal change disease with IgA deposition. Because spontaneous complete remission was observed after cessation of heroin, a diagnosis of minimal change nephrotic syndrome with IgA deposition associated with heroin abuse was considered.

CONCLUSION

This case showed minimal change nephrotic syndrome with IgA deposition that had a benign clinical course.

Vaccines in the Treatment of Substance Abuse

Reconceptualizing drugs as toxins allowed an important shift in the approach to the treatment of substance abuse, because it ushered in consideration of immunological methods of pharmacotherapy. This paradigm shift represented a dramatic departure from previously considered approaches to pharmacotherapy for substance use disorders (SUDs), which had up until that time focused predominantly on either agonist and/or antagonist medications meant to block drug effects or to decrease reward, reinforcement, or craving. Use of immunological theory in SUD treatment also meant that 1) a potentially addicting medication would not be administered as part of therapy and 2) side effects could be limited, because the individual's immune system would be responsible for delivering treatment.

Mechanism-based therapeutic approaches to rhabdomyolysis-induced renal failure

Rhabdomyolysis-induced renal failure represents up to 15% of all cases of acute renal failure. Many studies over the past 4 decades have demonstrated that accumulation of myoglobin in the kidney is central in the mechanism leading to kidney injury. However, some discussion exists regarding the mechanism mediating this oxidant injury. Although the free-iron-catalyzed Fenton reaction has been proposed to explain the tissue injury, more recent evidence strongly suggests that the main cause of oxidant injury is myoglobin redox cycling and generation of oxidized lipids. These molecules can propagate tissue injury and cause renal vasoconstriction, two of the three main conditions associated with acute renal failure. This review presents the evidence supporting the two mechanisms of oxidative injury, describes the central role of myoglobin redox cycling in the pathology of renal failure associated with rhabdomyolysis, and discusses the value of therapeutic interventions aiming at inhibiting myoglobin redox cycling for the treatment of rhabdomyolysis-induced renal failure.

Ibuprofen-related renal tubular acidosis in pregnancy

Ibuprofen-related renal tubular acidosis (RTA) has not been previously described in pregnancy but its occurrence outside of pregnancy is being increasingly described. In this case, a 34-year-old woman presented in the third trimester of pregnancy with Type 1 or distal RTA related to ibuprofen and codeine abuse. It was complicated by acute on chronic renal dysfunction and hypokalemia. Delivery at 37 weeks gestation due to concerns of evolving preeclampsia resulted in the birth of a healthy neonate. RTA and hypokalemia were remediated and ibuprofen and codeine abuse ceased. Some renal dysfunction however continued. Thorough and repeated history taking as well as vigilance for this condition is suggested.

Illicit opioid intoxication: diagnosis and treatment

Opioid intoxications and overdose are associated with high rates of morbidity and mortality. Opioid overdose may occur in the setting of intravenous or intranasal heroin use, illicit use of diverted opioid medications, intentional or accidental misuse of prescription pain medications, or iatrogenic overdose. In this review, we focused on the epidemiology of illict opioid use in the United States and on the mechanism of action of opioid drugs. We also described the signs and symptoms, and diagnoses of intoxication and overdose. Lastly, we updated the reader about the most recent recommendations for treatment and prevention of opioid intoxications and overdose.

Substance abuse issues in oral and maxillofacial practice

Substance abuse has far-reaching consequences for individuals, their families, and the community. Medications with abuse potential play an important role in the management of pain and are widely prescribed by the oral and maxillofacial surgeon. Reducing the likelihood of abuse and providing appropriate pain management for the known abuser are critical aspects of perioperative patient management. Health care providers are not immune to substance abuse and may, in fact, be at an elevated risk. Identification of impaired providers is essential to help them find the appropriate treatment and counseling and to prevent harm to their patients, family, friends, or associates.

[Anesthesia in drug addiction]

The growing social problem of drug abuse has increased the likelihood that anesthesiologists will find acute or chronic drug users among patients requiring anesthesia for elective or emergency surgery. We must therefore be aware of the effects drugs have on the organism and their possible pharmacokinetic and pharmacodynamic interactions with anesthetic agents in order to prevent complications during surgery and postoperative recovery. Such knowledge is required for the management of abstinence syndrome or overdose, which pose the greatest potential dangers for the hospitalized drug addict.

Non-drug-induced nephrotoxicity

Several drugs and other compounds can induce acute and/or chronic nephrotoxicity. The goal of this study was to review clinical features of nephrotoxicity induced by 'atypical' or 'unconventional' agents, such as environmental agents (metals, minerals, animals), food agents (mushrooms, aristolochic acid, medicinal traditional herbals, dietary supplements, melamine), drugs, and other products (ethylene glycol). Nephrotoxicity varies according to local background, dependent on different food and cultural customs, as well as to differences in local fauna and flora. The incidence of such a phenomenon is not well known. Many different pathophysiological pathways are involved, and the spectrum of renal lesions is rather wide. 'Epidemic nephrotoxicity' may occur, as recently illustrated by the melamine epidemics in Chinese infants receiving powdered milk formulas; a rapid reaction to unusual increased frequency of acute kidney injury and nephrolithiasis in young children has led to a rapid analysis from international experts, with subsequent recommendations for diagnosis and care. Nephrotoxicity should be considered when there is any unexplained renal impairment, especially in children.

Management of injecting drug users admitted to hospital

General hospital clinicians frequently deal with injecting drug users because substance use has diverse medical and psychiatric complications. Non-specialist clinicians often initiate management when specialist consultation is not available or accepted by the patient. Here, we summarise evidence for the management of hospitalised injecting drug users. The first challenge is to engage a drug user into medical care. A non-judgmental approach towards patients and acceptance of their lifestyle choices facilitates engagement. Pragmatic clinical goals can be negotiated and achieved. We also describe common conditions of injecting drug users. Accurate diagnosis and appropriate management focus on common issues such as intoxication, withdrawal, pain management, drug seeking, psychological comorbidity, behavioural difficulties, and pregnancy. Effective management can reduce the medical and social effect of these conditions and is not difficult.

Volatile solvent abuse caused glomerulopathy and tubulopathy in street children

Substance misuse among street children is a significant problem in developing countries. Volatile substances are the most abused agents. According to case reports, chronic renal diseases are common among substance-abusing street children. In this study, we examined the renal findings of 42 volatile substance–abusing street children and compared them with results from 49 healthy children (control). The street children’s weight, height, and blood pressure were lower than the controls’ ( P < 0.05). However, their blood alkaline phosphatase and creatinine phosphokinase levels were higher ( P < 0.05), and total blood protein, creatinine, and phosphorus levels were lower than the controls’ ( P < 0.05). Furthermore, the street children’s glomerular filtration rates were within normal limits ( P < 0.05), their urinary N-acetyl-beta-glucosaminidase (NAG), β2-microglobulin, microalbumin, protein, calcium, phosphorus, sodium, potassium, and chloride excretions were higher, and tubular phosphate reabsorption were lower than the controls’ ( P < 0.05). Volatile substances have been charged with causing distal tubular disease, but increased urinary protein, NAG, β2-microglobulin, microalbumin, and electrolyte excretions also result from glomerular, proximal, and distal tubular influences. We believe that increased volatile substance products in the renal parenchyma are responsible for glomerular and tubular damage. Volatile substance–abusing street children should be examined for glomerular and proximal tubular function and distal tubular acidosis.