Descriptive analysis of poisoning cases involving attention deficit hyperactivity disorder medications in Hong Kong.

INTRODUCTION: The number of poisoning cases involving attention deficit hyperactivity disorder (ADHD) medications has reportedly risen with their increased use. However, there is limited relevant evidence from Asia. We analysed the characteristics of poisoning events involving these medications in Hong Kong. METHODS: We retrieved data regarding ADHD medication-related poisoning cases from the Hong Kong Poison Information Centre and conducted a descriptive analysis of the demographic information and poisoning information including sources of cases, exposure reason, exposure location, and outcome. The HKPIC data were linked with the Hospital Authority Clinical Data Analysis and Reporting System (CDARS) via de-identified Accident and Emergency numbers of public hospitals to investigate clinical characteristics. We also retrieved ADHD medication prescription records from the CDARS, then compared trends between poisoning cases and ADHD medication use. RESULTS: We identified 72 poisoning cases involving ADHD medications between 2009 and 2019, of which approximately 70% occurred in the affected individual's residence; most were intentional poisoning events (65.3%). No statistically significant association was observed between ADHD medication prescription trends and poisoning events involving ADHD medications. Of the 66 cases (91.7%) successfully linked to CDARS, 40 (60.6%) occurred in individuals with ADHD (median age: 14 years); 26 (39.4%) occurred in individuals who lacked ADHD (median age: 33 years) but displayed higher rates of other mental disorders including depression and anxiety. CONCLUSION: No significant correlation was evident between ADHD medication prescriptions and poisoning events involving ADHD medications. However, medication management and caregiver education must be emphasised to prevent potential poisoning events.

Efficacy and safety of naltrexone for amfetamine and methamfetamine use disorder: a systematic review of randomized controlled trials.

INTRODUCTION: Amfetamine and methamfetamine abuse remains a prevalent health problem, increasing the burden on healthcare. Naltrexone, a µ-opioid receptor antagonist, has been suggested as a promising treatment for amfetamine and methamfetamine use disorder. OBJECTIVE: To review the current evidence for the efficacy and safety of naltrexone as a pharmacological treatment for amfetamine and methamfetamine use disorder. The primary outcome was defined as abstinence or reduction of use. Secondary outcomes were, attenuated "positive" subjective effects (e.g., "feel good," "craving," etc.) of amfetamine or methamfetamine after naltrexone treatment, adverse events and physiological changes (e.g., blood pressure, heart rate). METHODS: This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A systematic literature search was conducted on 2 April 2017, and updated on 31 March 2018. Records were retrieved from databases including PubMed, EMBASE Classic plus EMBASE 1980 via Ovid, and the databases were searched using keywords and/or headings: (naltrexone AND amfetamine AND dependence) OR (naltrexone AND amfetamine AND craving) OR (vivitrol AND amfetamine) OR (revia AND amfetamine) OR (naltrexone AND amfetamine) OR (naltrexone AND methamfetamine dependence) OR (naltrexone AND methamfetamine AND craving) OR (vivitrol AND methamfetamine) OR (revia AND methamfetamine) OR (naltrexone AND ice) OR (naltrexone AND crystal meth) OR (naltrexone AND methamfetamine). Studies investigating the effects of naltrexone on amfetamine or methamfetamine use were eligible for inclusion. All studies were rated as low risk of bias using the Cochrane tool for risk of bias. RESULTS: Among 591 identified studies, there were four randomized controlled trials. Two studies investigated the effects of naltrexone on amfetamine use disorder and two on methamfetamine use. Compared to placebo, the abstinence rate was increased significantly (p < 0.05) by naltrexone in one of two amfetamine studies, whereas there was no statistical difference in the only study reporting methamfetamine use. In one out of two amfetamine studies, naltrexone significantly attenuated either craving levels or subjective effects (e.g., "want more," "like effect") relative to placebo (p < 0.05). Additionally, only in one of two methamfetamine studies did naltrexone produce a significant reduction (p < 0.05) in craving levels or attenuated subjective effects. Both amfetamine and methamfetamine studies showed good tolerability of naltrexone, with few adverse events seen. CONCLUSIONS: There is presently insufficient evidence to support the use of naltrexone in amfetamine and metamfetamine use disorders. There is a compelling need for high-quality studies to further evaluate the potential use of naltrexone.

Injuries and envenomation by exotic pets in Hong Kong.

INTRODUCTION: Exotic pets are increasingly popular in Hong Kong and include fish, amphibians, reptiles, and arthropods. Some of these exotic animals are venomous and may cause injuries to and envenomation of their owners. The clinical experience of emergency physicians in the management of injuries and envenomation by these exotic animals is limited. We reviewed the clinical features and outcomes of injuries and envenomation by exotic pets recorded by the Hong Kong Poison Information Centre. METHODS: We retrospectively retrieved and reviewed cases of injuries and envenomation by exotic pets recorded by the Hong Kong Poison Information Centre from 1 July 2008 to 31 March 2017. RESULTS: There were 15 reported cases of injuries and envenomation by exotic pets during the study period, including snakebite (n=6), fish sting (n=4), scorpion sting (n=2), lizard bite (n=2), and turtle bite (n=1). There were two cases of major effects from the envenomation, seven cases with moderate effects, and six cases with mild effects. All major effects were related to venomous snakebites. There were no mortalities. CONCLUSION: All human injuries from exotic pets arose from reptiles, scorpions, and fish. All cases of major envenomation were inflicted by snakes.

Mushroom poisoning in Hong Kong: a ten-year review.

INTRODUCTION: Mushroom poisoning is a cause of major mortality and morbidity all over the world. Although Hong Kong people consume a lot of mushrooms, there are only a few clinical studies and reviews of local mushroom poisoning. This study aimed to review the clinical characteristics, source, and outcome of mushroom poisoning incidences in Hong Kong. METHODS: This descriptive case series review was conducted by the Hong Kong Poison Information Centre and involved all cases of mushroom poisoning reported to the Centre from 1 July 2005 to 30 June 2015. RESULTS: Overall, 67 cases of mushroom poisoning were reported. Of these, 60 (90%) cases presented with gastrointestinal symptoms of vomiting, diarrhoea, and abdominal pain. Gastrointestinal symptoms were early onset (<6 hours post-ingestion) and not severe in 53 patients and all recovered after symptomatic treatment and a short duration of hospital care. Gastrointestinal symptoms, however, were of late onset (≥6 hours post-ingestion) in seven patients; these were life-threatening cases of amatoxin poisoning. In all cases, the poisonous mushroom had been picked from the wild. Three cases were imported from other countries, and four collected and consumed the amatoxin-containing mushrooms in Hong Kong. Of the seven cases of amatoxin poisoning, six were critically ill, of whom one died and two required liver transplantation. There was one confirmed case of hallucinogenic mushroom poisoning caused by Tylopilus nigerrimus after consumption of a commercial mushroom product. A number of poisoning incidences involved the consumption of wild-harvested dried porcini purchased in the market. CONCLUSION: Most cases of mushroom poisoning in Hong Kong presented with gastrointestinal symptoms and followed a benign course. Life-threatening cases of amatoxin poisoning are occasionally seen. Doctors should consider this diagnosis in patients who present with gastrointestinal symptoms that begin 6 hours or more after mushroom consumption.

Paracetamol overdose in Hong Kong: is the 150-treatment line good enough to cover patients with paracetamol-induced liver injury?

OBJECTIVES: To evaluate the failure rate of the 150-treatment line for paracetamol overdose in Hong Kong, and the impact if the treatment threshold was lowered. SETTING: Public hospitals, Hong Kong. PATIENTS: All patients with acute paracetamol overdose reported to the Hong Kong Poison Information Centre from 1 January 2011 to 31 December 2013 were studied and analysed for the timed serum paracetamol concentration and their relationship to different treatment lines. Presence of significant liver injury following paracetamol overdose was documented. The potential financial burden of different treatment lines implemented locally was estimated. RESULTS: Of 893 patients, 187 (20.9%) had serum paracetamol concentration above the 150-treatment line, 112 (12.5%) had serum paracetamol concentration between the 100- and 150-treatment lines, and 594 (66.5%) had serum paracetamol level below the 100-treatment line. Of the 25 (2.8%) patients who developed significant liver injury, two were between the 100- and 150-treatment lines, and the other two were below the 100-treatment line. The failure rate of the 150-treatment line was 0.45%. Lowering the treatment threshold to the 100-treatment line might lower the failure rate of the treatment nomogram to 0.22% but approximately 37 more patients per year would need to be treated. It would incur an additional annual cost of HK$189 131 (US$24 248), and an additional 1.83 anaphylactoid reactions per year. The number needed-to-treat to potentially reduce one significant liver injury is 112. CONCLUSIONS: Lowering the treatment threshold of paracetamol overdose may reduce the treatment-line failure rate. Nonetheless such a decision must be balanced against the excess in treatment complications and health care resources.

Surveillance of emerging drugs of abuse in Hong Kong: validation of an analytical tool.

OBJECTIVE: To validate a locally developed chromatography-based method to monitor emerging drugs of abuse whilst performing regular drug testing in abusers. DESIGN: Cross-sectional study. SETTING: Eleven regional hospitals, seven social service units, and a tertiary level clinical toxicology laboratory in Hong Kong. PARTICIPANTS: A total of 972 drug abusers and high-risk individuals were recruited from acute, rehabilitation, and high-risk settings between 1 November 2011 and 31 July 2013. A subset of the participants was of South Asian ethnicity. In total, 2000 urine or hair specimens were collected. MAIN OUTCOME MEASURES: Proof of concept that surveillance of emerging drugs of abuse can be performed whilst conducting routine drug of abuse testing in patients. RESULTS: The method was successfully applied to 2000 samples with three emerging drugs of abuse detected in five samples: PMMA (paramethoxymethamphetamine), TFMPP [1-(3-trifluoromethylphenyl)piperazine], and methcathinone. The method also detected conventional drugs of abuse, with codeine, methadone, heroin, methamphetamine, and ketamine being the most frequently detected drugs. Other findings included the observation that South Asians had significantly higher rates of using opiates such as heroin, methadone, and codeine; and that ketamine and cocaine had significantly higher detection rates in acute subjects compared with the rehabilitation population. CONCLUSIONS: This locally developed analytical method is a valid tool for simultaneous surveillance of emerging drugs of abuse and routine drug monitoring of patients at minimal additional cost and effort. Continued, proactive surveillance and early identification of emerging drugs will facilitate prompt clinical, social, and legislative management.

Recipes and general herbal formulae in books: causes of herbal poisoning.

Traditional Chinese medicine is commonly used locally, not only for disease treatment but also for improving health. Many people prepare soups containing herbs or herbal decoctions according to recipes and general herbal formulae commonly available in books, magazines, and newspapers without consulting Chinese medicine practitioners. However, such practice can be dangerous. We report five cases of poisoning from 2007 to 2012 occurring as a result of inappropriate use of herbs in recipes or general herbal formulae acquired from books. Aconite poisoning due to overdose or inadequate processing accounted for three cases. The other two cases involved the use of herbs containing Strychnos alkaloids and Sophora alkaloids. These cases demonstrated that inappropriate use of Chinese medicine can result in major morbidity, and herbal formulae and recipes containing herbs available in general publications are not always safe.

Chinese herbal medicine-induced anticholinergic poisoning in Hong Kong.

OBJECTIVE: To study the epidemiology, causes, and clinical course of Chinese herbal medicine-induced anticholinergic poisoning in Hong Kong. DESIGN: Case series. SETTING: Hong Kong. PATIENTS: All case histories of Chinese herbal medicine-induced anticholinergic poisoning (with laboratory confirmation) recorded by the Hong Kong Poison Information Centre over a 93-month period were accessed for analysis. RESULTS: During the relevant period, 22 clusters of Chinese herbal medicine-induced anticholinergic poisoning involving 32 patients were retrieved. The commonest clinical features were mydriasis (n=32, 100%) and confusion (n=24, 75%). No gastro-intestinal decontamination was performed. None of these patients underwent intubation, defibrillation, cardioversion, pacing, fluid resuscitation, inotropic support or dialysis. Of the 32 patients, 17 (53%) were treated with physostigmine because of confusion, three of whom had previously received intravenous benzodiazepines. No patient could be effectively treated with benzodiazepines alone. There was no mortality, and all the patients were discharged within 3 days. None of them re-attended the emergency department within 1 week of discharge. The commonest cause was the substitution of flos campsis (Campsis grandiflora) by the flower of the Datura species (7 clusters [32%] in 10 patients). CONCLUSION: Mydriasis and confusion were the commonest clinical features of Chinese herbal medicine-induced anticholinergic poisoning in Hong Kong. Physostigmine was frequently used in the treatment; benzodiazepines appeared ineffective. The commonest cause was the substitution of flos campsis (Campsis grandiflora) by the flower of the Datura species.

Dettol poisoning and the need for airway intervention.

OBJECTIVES. To (1) characterise the clinical features of Dettol poisoning on a territory-wide basis, (2) assess the need for airway intervention after such poisoning and its time frame after ingestion, and (3) identify predictors for such an intervention. DESIGN. Case series. SETTING. Sixteen accident and emergency departments in Hong Kong. PATIENTS. Patients with Dettol ingestion who presented within 48 hours of ingestion from July 2005 to June 2009, derived from the database of the Hong Kong Poison Information Centre. RESULTS. In all, 213 patient records were identified, of which 36 were excluded based on pre-defined criteria and 177 were analysed. Among the latter, the median age was 32 (range, 2-95) years and the male-to-female ratio was 1:2.7 (48:129). Intentional ingestion constituted the majority (95%) of cases. The most common symptoms were related to the local irritative/corrosive effects on the aero-digestive tract, such as gastro-intestinal upset and localised throat pain. Airway intervention was required in 14 (8%) patients. All interventions were performed within 12 hours of Dettol ingestion and three cases involved re-intubation after extubation. Univariate analysis showed that a Glasgow Coma Scale score of <8, older age, a larger amount ingested, lip swelling, lung crackles, and wheezing were all associated with airway intervention. In the multivariate analysis using forward stepwise logistic regression, only coma (Glasgow Coma Scale score of <8) remained statistically significant. CONCLUSIONS. Delayed airway obstruction (>12 hours after Dettol ingestion) is unlikely. For those who are intubated, careful assessment of airway adequacy before extubation is strongly recommended to avoid extubation failure and subsequent re-intubation. Patients in coma (Glasgow Coma Scale score of <8) should prompt airway intervention.

Green pit viper antivenom from Thailand and Agkistrodon halys antivenom from China compared in treating Cryptelytrops albolabris envenomation of mice.

OBJECTIVE: To compare the relative efficacy of the green pit viper antivenom from Thailand and Agkistrodon halys antivenom from China. DESIGN. In-vivo experimental study. SETTING: A wildlife conservation organisation, a university, a poison information centre, and a regional hospital in Hong Kong. MAIN OUTCOME MEASURES: Pre- and post-antivenom lethal dose 50 (LD50) of the Cryptelytrops albolabris venom, median effective dose (ED50) of green pit viper antivenom and Agkistrodon halys antivenom against a lethal dose of the venom. SUBJECTS. Adult mice. RESULTS: The intraperitoneal LD50 of the venom from locally caught Cryptelytrops albolabris was 0.14 microL. After post-exposure treatment with 10 microL of antivenom, it was elevated to 0.36 microL and 0.52 microL by the green pit viper antivenom and the Agkistrodon halys antivenom, respectively. The ED50 was 32.02 microL for green pit viper antivenom and 6.98 microL for Agkistrodon halys antivenom. Both green pit viper antivenom and Agkistrodon halys antivenom ameliorated the lethality of Cryptelytrops albolabris venom in mice. CONCLUSION: The overall superior neutralisation capacity of Agkistrodon halys antivenom over green pit viper antivenom may be related to the geographic proximity of the venoms used for antivenom preparation. The results point towards the need for further comparison of the two antivenoms on protein or immunoglobulin weight basis, and with respect to non-lethal clinically significant toxicities.

Observation of symmetrical reflection sidebands in a silica suspended-core fiber Bragg grating.

We have observed symmetrical sidebands in reflection from Bragg grating written in a silica suspended-core fiber, which are caused by longitudinal periodic refractive index modulation in the Ge-doped suspended-core fiber with a core diameter of approximately 1.3 microm. Our simulation shows that the effective refractive index of the guided mode varied by 0.023% along the fiber with a period of approximately 650 microm. The periodic index variation can lead to amplitude modulation of fiber Bragg gratings, which can be studied by observing the spectra of a fiber Bragg grating written in the Ge-doped core. In addition, we have also characterized the temperature and strain responses of the fiber Bragg gratings, and showed that both responses in the suspended-core fiber are 20 to 25% lower than that of a fiber Bragg grating written on a conventional fiber.

Emergency department presentation of ketamine abusers in Hong Kong: a review of 233 cases.

OBJECTIVES: To study the acute clinical presentations of ketamine abusers in Hong Kong. DESIGN: Retrospective chart review. SETTING: Fifteen accident and emergency departments in Hong Kong. PATIENTS: Consultations associated with recent ketamine use either confirmed by history or urine test were searched for from the database of the Hospital Authority Hong Kong Poison Information Centre from 1 July 2005 to 30 June 2008. Their medical records and investigation results were analysed. RESULTS: A total of 233 records of ketamine use were included for review. Patient ages ranged from 13 to 60, with a median of 22 years, and the male-to-female ratio being 2.1:1. The most common symptoms of ketamine misuse were impaired consciousness (45%), abdominal pain (21%), lower urinary tract symptoms (12%), and dizziness (12%). The most common abnormal physical findings were high blood pressure (40%), followed by tachycardia (39%), abdominal tenderness (18%), and white powder in the nostrils (17%). CONCLUSION: Most ketamine abusers presented acutely with transient central nervous system depression, abdominal pain, or lower urinary tract symptoms. Clinicians should be alert to the typical age-group, signs and symptoms of such abusers presenting in an acute medical setting.

Prolonged myoclonus after a single bolus dose of propofol.

Propofol is a commonly used anaesthetic agent and is rarely associated with seizure-like phenomena. This case report presents a young woman with seizure-like phenomena lasting more than 4 weeks after a single dose of propofol. The underlying pathophysiology of this condition is poorly understood but a psychological component is possible in this case.

Reversible intraventricular conduction defect in aconitine poisoning.

Chinese medicine plays an important role in providing medical care for people in countries with large Chinese communities, including Hong Kong. The aconite herb is one of the commonly-prescribed ingredients for various clinical problems. However, due to its narrow therapeutic index, toxicities are not uncommonly encountered, including life-threatening cardiac arrhythmias like ventricular arrhythmias. We report a 57-year-old woman with reversible intraventricular conduction defect attributed to the use of processed Fuzi.

Life-threatening Torsades de Pointes resulting from "natural" cancer treatment.

INTRODUCTION: Nonradioactive cesium chloride (CsCl) is used by some alternative medicine advocates as a treatment for cancer. The therapy was proven to be neither safe nor effective. Chronic use of CsCl has resulted in cases with severe cardiotoxicity. CASE REPORT: A 65-year-old lady presented to our hospital's accident and emergency department with recurrent syncope attacks. Electrocardiogram monitoring showed QT prolongation and transient Torsades de Pointes (TDP) ventricular tachycardia. She was taking anticancer naturopathic drugs for 6 weeks before admission. One of her naturopathic drugs was subsequently confirmed containing 89% CsCl by weight. Besides conventional treatment of QT prolongation and TDP, the patient was given a 4-week course of oral Prussian blue to enhance gastrointestinal elimination of cesium. The serum half-life of cesium was reduced from 61.7 to 29.4 days after the use of Prussian blue. QT prolongation was normalized in 27 days. DISCUSSION: To our knowledge, this is the first published case of nonradioactive cesium poisoning treated with Prussian blue. A transient rise in serum cesium level was observed during Prussian blue therapy. Possible explanations for this observation include poor drug compliance during outpatient treatment and redistribution of cesium from body stores. CONCLUSION: Nonradioactive CsCl poisoning can result in severe cardiotoxicity with QT prolongation and TDP ventricular tachycardia. The key points in the management of nonradioactive cesium poisoning include cessation of cesium exposure, vigorous electrolytes replacement, and oral Prussian blue therapy.

Outbreak of hypoglycaemia: sexual enhancement products containing oral hypoglycaemic agent.

OBJECTIVES: To describe a cluster of Hong Kong subjects with hypoglycaemia, after they had taken various non-prescription sildenafil products containing glibenclamide. DESIGN: Retrospective study. SETTING: A tertiary referral centre for clinical toxicology analysis in Hong Kong. PATIENTS: All men referred to the laboratory for investigation of suspected drug-induced hypoglycaemia from December 2007 to September 2008. MAIN OUTCOME MEASURES: The characteristics of these patients, including their clinical presentations, outcomes, drug history, urine toxicology analysis results, and in some instances, analysis results of unused products. RESULTS: A total of 144 male patients were referred for suspected drug-induced hypoglycaemia. Sildenafil and glibenclamide, or their metabolites, were detected in the urine specimens of 68 (47%) patients, none of whom had been prescribed either drug by a registered medical practitioner. Among these subjects, 24 (35%) denied any use of sexual enhancement products despite repeated questioning. Eight patients had repeated exposure resulting in re-admission. The sources of these sexual enhancement products included pharmacies in Mainland China, friends, local pharmacies, peddlers, or were unknown. Three patients died, one remains in a vegetative state and one suffered cognitive impairment; the remaining 63 recovered fully. Twenty-five unused sexual enhancement products of seven different kinds were recovered for analysis. The median (range) of sildenafil and glibenclamide per unit dose was 64 (0.05-198) mg and 70 (0-158) mg, respectively. CONCLUSION: These illegal products pose a severe and continued threat to society and therefore deserve widespread vigilance, so that such products can be eradicated at their source.

Systematic review of controlled clinical trials of gastric lavage in acute organophosphorus pesticide poisoning.

BACKGROUND: Organophosphorus pesticide (OP) self-poisoning is a major problem in the developing rural world. There is little clinical trial data to guide therapy, hindering the identification of best therapy. Despite the recognition of adverse effects, gastric lavage is commonly done in Asia. We aimed to identify studies assessing its effectiveness. METHOD: We systematically searched the literature for controlled clinical studies that assessed the effect of gastric lavage in OP pesticide self-poisoning. RESULTS: All 56 studies identified were Chinese and reported benefit from the intervention studied, including multiple gastric lavages, use of norepinephrine or pralidoxime in the lavage fluid, concurrent treatment with naloxone or scopolamine, insertion of the gastric tube via a laparotomy incision, and lavage later than 12 h post-ingestion. However, only 23 were RCTs and none presented adequate methodology for their quality to be assessed. The patient population and study treatment protocol were not defined - large variation in case fatality in the control arm of the studies (from 4.5 to 93%) suggests marked variation between studies and likely between study arms. No study compared an intervention against a control group receiving no gastric lavage or provided any data to indicate whether a significant quantity of poison was removed. CONCLUSION: Despite widespread use of multiple gastric lavages for OP pesticide poisoning across Asia, there is currently no high-quality evidence to support its clinical effectiveness. There is a need for studies to identify in which patients and for what duration gastric lavage is able to remove significant quantities of poison. Following these studies, large clinical trials will be required to address the effectiveness and safety of gastric lavage (either single or multiple) in acute OP pesticide poisoning.

'Street ketamine'-associated bladder dysfunction: a report of ten cases.

Ten young ketamine abusers presented with lower urinary tract symptoms to two regional hospitals in Hong Kong. Investigations demonstrated contracted bladders and other urinary tract abnormalities. These types of findings have never been reported before in ketamine abusers. The possible aetiology is also discussed.

Two cases of valproic acid poisoning treated with L-carnitine.

Two cases of acute valproic acid poisoning with central nervous system depression and raised ammonia level without hepatotoxicity were reported. They were treated successfully with the use of the antidotes: L-carnitine and other supportive measures. Clinical manifestation and progress was described, and discussion is focused on the use of L-carnitine in valproic acid-induced hyperammonemia, from its mechanism to the clinical experiences in the literature. Based on the favorable response of our two cases and the literature review, we recommend the administration of intravenous L-carnitine in patients of valproic acid overdose with hyperammonemia or valproic acid-induced hyperammonemic encephalopathy and hepatotoxicity at a dose of 50 mg/kg every 8 h for the first initial 24 h with further individual assessment.