Phenytoin Intoxication in a Patient Receiving a Therapeutic Dose for Postoperative Seizure Prophylaxis: A Case Study.

OBJECTIVE: Phenytoin is commonly prescribed to prevent postoperative seizures. Despite the rarity of the CYP2C9 genetic polymorphism, which may result in poor phenytoin metabolism, in the Thai population, the authors report a case of phenytoin toxicity in a patient with poor metabolism administered with a standard dose of phenytoin. CASE REPORT: A 58-year-old Thai woman presented to the outpatient clinic with a 2-day history of nausea, vomiting, and dizziness. She underwent craniotomy for tumor removal 2 weeks after being diagnosed with tuberculum sellae meningioma. After the surgery, she was prescribed 300 mg of phenytoin daily to prevent seizures. During the physical examination, ataxia, horizontal nystagmus, and cerebellar abnormalities were observed, with an initial serum phenytoin concentration of 58.85 mg/L. The brain imaging results were unremarkable. Omeprazole was the only recognized drug interaction; however, it is highly unlikely to account for this condition. Pharmacogenetic investigation of CYP2C9 revealed a homozygous CYP2C9*3/*3 mutation, which is indicative of suboptimal drug metabolism and can reduce phenytoin metabolism by 50%. This patient was administered repeated dosages of activated charcoal over the course of 2 days. Her symptoms eventually subsided, with the phenytoin levels dropping to 29.51 mg/L. CONCLUSIONS: In the absence of an overdose history or drug-drug interaction, CYP2C9 polymorphism should be suspected in patients with phenytoin toxicity. In such situations, the phenytoin dosage must be decreased and monitored closely.

Sensitivity of dose-estimations for acute acetaminophen overdose in predicting hepatotoxicity risk using the Rumack-Matthew Nomogram.

Timely assessment of acetaminophen concentration in overdose situations is not always available in resource-poor settings. The 150 mg/kg dose-estimate for acetaminophen is widely considered as criterion for acetaminophen overdose. Its sensitivity and specificity when compared to the 150 mg/L treatment line on the Rumack-Matthew Nomogram (150-treatment line) has rarely been evaluated. This is a retrospective chart review of acute acetaminophen overdose patients. We evaluated the sensitivity and specificity of the 150, 200 mg/kg and 8- and 10-g dose-estimates by plotting the serum acetaminophen levels and using 150-treatment line on the Nomogram as the treatment cut-off. A comparison of medical care costs was performed. We enrolled 784 cases for analysis. Median (IQR) age was 23 (20-28) years (81.9% female). There were 545 cases (69.5%) where the estimated ingested acetaminophen dose were ≥150 mg/kg and 406 cases (51.8%) with concentrations ≥150-treatment line. Hepatotoxicity and acute liver injury (ALI) occurred in 7.3% and 23.9%, respectively. The sensitivity and specificity of 150 mg/kg dose-estimate for the 150-treatment line were 92.6% (95% CI 89.6, 94.8) and 55.3% (95% CI 50.3, 60.2). Among patients with dose-estimate below150 mg/kg, none developed hepatotoxicity and 17 (7.1%) develop ALI. The administration of activated charcoal significantly decreased the risk of being above the 150-treatment line by half. In resource-poor setings, the use of 150 mg/kg dose-estimate as a stand-alone criteria for initiation of N-acetylcysteine therapy is satisfactory, especially when combined with decontamination with activated charcoal and follow up of aminotransferase at 24 h.

Prevalence and cluster effect of self-reported allergic reactions among insect consumers.

BACKGROUND: Entomophagy is a common practice in many parts of the world. Allergic symptoms after insect consumption have been reported in healthcare literature and in the news. OBJECTIVE: We evaluated prevalence and association of allergic history and self-reported allergic reactions after entomophagy. METHODS: We conducted a cross sectional internet-based survey. Participants were people who have consumed insects. Collected information included demographic data, the practice of entomophagy, allergic history and self-reported allergic symptoms. RESULTS: During May to October 2017, 140 people completed the survey. Median and range of age are 27 and 18-64 years. Ninety-two (65.7%) were female. Thirty-seven (26.4%) and 13 (9.3%) participants had history of allergy and seafood allergy, respectively. Eighteen (12.9%; 95% confidence intervals (CI) 7.3-18.4) participants reported allergic reactions after insect consumption. Nine symptomatic participants reported other people who partook insects to have allergic symptoms. Reported factors with significant association with allergic reactions were history of allergy and seafood allergy with prevalence ratios of 4.83 (CI 1.83-10.44) and 3.76 (CI 1.59-8.87), respectively. CONCLUSIONS: The prevalence of self-reported allergic reactions after entomophagy is 12.9%. Clusters of people with post-entomophagy allergic symptoms are found. History of allergy and seafood allergy are associated with post-entomophagy allergic reactions.

Effects of unconventional recreational drug use in pregnancy.

Recreational drug toxicity is a rapidly evolving aspect in clinical practice. The prevalence of recreational drug abuse in the past decade has achieved an epidemic scale due to invention of new agents and ease of accessibility to the abused drugs. "Unconventional recreational drugs" is the term that includes new psychoactive drugs and medications diverted for recreational goals. Misuse of unconventional recreational drugs during pregnancy can affect both the pregnant woman and the fetus. However, the problems are usually unrecognized and overlooked by healthcare professionals. In this articles, obstetric complications, teratogenicity and neonatal abstinence syndrome from exposure during pregnancy to synthetic cannabinoids, synthetic cathinones, tramadol, kratom, olanzapine, quetiapine, ketamine and ketamine are reviewed. The main purpose is to create awareness about maternal, fetal and neonatal effects of these unconventional recreational drugs, so healthcare professionals will have improved vigilance for these under-recognized issues.

Histamine poisoning from insect consumption: an outbreak investigation from Thailand.

BACKGROUND: Insect consumption is a common practice in the Asian culture and all over the world. We are reporting an outbreak investigation of histamine poisoning from ingestion of fried insects. METHODS: On 24 July 2014, a group of students at a seminar presented to Angthong Provincial Hospital, Thailand, with pruritic rash after ingesting snacks consisting of fried insects from a vendor. We initiated an outbreak investigation with retrospective cohort design and collected samples of remaining foods for analyses. Attack rates, relative risks and their confidence intervals (CI) were calculated. RESULTS: Out of 227 students, 28 developed illnesses that were consistent with our case definition which included, flushing, pruritus, urticarial rashes, headache, nausea, vomiting, diarrhea, dyspnea and bronchospasm. Two children were hospitalized for progressive bronchospasm overnight without serious complications. The types of food ingested included a lunch that was provided at the seminar for all students and snacks that 41 students bought from the only vendor in the vicinity. The snacks included fried grasshoppers, silkworm pupae, common green frogs, bamboo borers, crickets and meat balls. The attack rates were highest (82.6 and 85.0%) among students who ingested fried grasshoppers and silkworm pupae and lowest (4.4 and 5.3%) among those who did not ingest them, with relative risk of 18.7 (95% CI 9.6-36.4) for grasshoppers and 16.0 (95% CI 8.8-29.3) for silkworm pupae. Histamine concentrations in the fried grasshoppers and silkworm pupae were 9.73 and 7.66 mg/100g, respectively. DISCUSSION AND CONCLUSION: Through epidemiological analysis and laboratory confirmation, we have illustrated that histamine poisoning can occur from ingestion of fried insects. We postulate that histidine, which is present in high concentration in grasshoppers and silkworm pupae, is decarboxylated by bacteria to histamine, a heat stable toxin. The ingestion of histamine is responsible for the clinical pictures being reported.

Being overweight or obese as a risk factor for acute liver injury secondary to acute acetaminophen overdose.

PURPOSE: Increased incidences of hepatotoxicity have been observed in obese patients with acute acetaminophen overdose. We evaluate whether the status of being overweight or obese is associated with increase in the development of hepatotoxicity and acute liver injury (ALI) in patients with acute acetaminophen overdose. METHODS: This was a retrospective cohort study comparing the risk of hepatotoxicity and ALI between overweight or obese patients (body mass index [BMI] ≥ 25) and normal BMI patients (BMI ≤ 24.9) presenting with acute acetaminophen overdose at Siriraj Hospital during January 2004 to June 2012. All patients were treated with intravenous N-acetylcysteine. Psi parameters were calculated. High psi was defined as psi of ≥5.0 mM-hour. Data were analyzed using multinomial logistic regressions, odds ratio (OR), stratified OR, and 95% confidence interval (CI). RESULTS: There were 197 patients who fulfilled the criteria for analysis, 35 (17.8%) were obese, 24 (12.2%) were overweight, and 138 (70%) were normal BMI cases. Hepatotoxicity and ALI developed in 25 (12.7%) and 40 (20.3%) cases, respectively. Multinomial logistic regression revealed that the overweight-obesity status and log10 (psi value) were significant risk factors of ALI, with OR (95% CI) of 2.68 (1.21-5.95) and 1.74 (1.27-2.38), respectively, while only log10 (psi) was a significant risk factor of hepatotoxicity with OR (95% CI) 378.51 (39.49-3627.99). From stratification, overweight-obesity had significant odds ratios for ALI in strata with low acetaminophen concentration, early initiation of N-acetylcysteine and low psi. CONCLUSION: We conclude that being overweight or obese is an independent risk factor of ALI in acute acetaminophen overdoses.

Transfer of Methamphetamine (MA) into Breast Milk and Urine of Postpartum Women who Smoked MA Tablets during Pregnancy: Implications for Initiation of Breastfeeding.

BACKGROUND: Methamphetamine (MA) use by pregnant women remains a growing problem in South East Asia. After delivery, a negative maternal urine MA assay is assumed to reflect the absence of MA in breast milk and marks breastfeeding initiation. To date, no data exist that describe the relationship between the peripartum and postpartum transfer of MA into breast milk and its urinary excretion in women, following recreational use by smoking. OBJECTIVE: This study aimed to determine the pharmacokinetic of smoked MA in breast milk and its relationship to urinary MA excretion in postpartum women who tested positive for MA before delivery. METHODS: Timed urine and breast milk samples of 33 women who had positive urine drug screens for MA prior to delivery were analyzed for MA using Acquity Ultra Performance Liquid Chromatography (Waters, Milford, Massachusetts, USA) with the ACQUITY UPLC Photodiode Array Detector (Waters). Those participants with 4 or more timed breast milk samples were included for pharmacokinetic calculation using log-linear trapezoidal rule. RESULTS: Pharmacokinetic data from 2 women were analyzed. The half-life values for MA in the breast milk were 11.3 and 40.3 hours. The absolute infant doses were 21.3 and 51.7 µg/kg/day. Methamphetamine disappears from breast milk approximately 1 day before the maternal urine MA becomes negative. CONCLUSION: Smoked MA shows a similar breast milk pharmacokinetic pattern to previously reported intravenous MA. Breastfeeding can be safely initiated in mothers whose urine MA screen has turned negative for ≥ 24 hours. However, concurrent maternal substance use treatment and screening is necessary for continued promotion of lactation.

Global patterns of methamphetamine use.

PURPOSE OF REVIEW: As the most popular psychostimulant in the world, methamphetamine use has reached epidemic proportions. Its enormous popularity has created subcultures of methamphetamine users all over the globe. The purpose of this review is to describe the geographic availability of different types of methamphetamine, the characteristics of each user population, and the psychosocial impact the two have on society. RECENT FINDINGS: Methamphetamine has diversified immensely from the early days of its use. Different forms of methamphetamine - ICE, powder, and pills - have different pharmacokinetic characteristics that make them popular among certain types of users. New studies have shown that addiction to methamphetamine results in a very characteristic loss of inhibition that augments various risk-taking behaviors in its users. Also, recent seizure data suggest that its production and trafficking is spreading into new areas of the globe. SUMMARY: From recreational use to addiction, methamphetamine use represents a serious risk to health and wellbeing of the community. Recognizing the pattern of abuse in specific populations is the key to assessing the risk, implementing prevention, and harm reduction measures, as well as making public policies.

Acetaminophen Psi Nomogram: a sensitive and specific clinical tool to predict hepatotoxicity secondary to acute acetaminophen overdose.

BACKGROUND: Acetaminophen Psi Parameter (APP) is a composite of acetaminophen (paracetamol) level and lag time before N-acetylcysteine (NAC) therapy. The APP is a significant predictor of hepatotoxicity secondary to acute acetaminophen overdose. Acetaminophen Psi Nomogram (APN) was invented as a graphic analog of the APP for use in predicting individual patient's risk of hepatotoxicity. Clinical accuracy of the APN has never been validated OBJECTIVE: The authors are reporting the validity of APN in predicting hepatotoxicity secondary to acute acetaminophen overdose at Siriraj Hospital. MATERIAL AND METHOD: This present study is a retrospective review of medical records of patients with acute acetaminophen overdose at Siriraj Hospital between January 2004 and June 2009. Each case was classified by APN into an appropriate risk group. The outcome of interest was hepatotoxicity. The validity of the APN is reported as sensitivity and specificity. Secondary outcomes include serum acetaminophen concentrations, delay to NAC therapy, and APP for each APN's risk group. RESULTS: One hundred and sixty-one patients were enrolled Higher APN risk classifications are associated with a trend towards higher acetaminophen levels, longer delayed to NAC initiation, and larger APP. Twenty five patients (15.5%) developed hepatotoxicity. The number of patients who were above the APN's risk lines, 1% and 50% were 88 (54.7%) and 17 (10.6%), respectively, with corresponding sensitivities of 100.0% (95% CI 186.6, 100.0) and 40.0% (95% C121.2, 61.3). APN's risk lines 50% had specificity of 94.9% (95% CI 89.7, 97.9). CONCLUSION: Acetaminophen Psi Nomogram is a sensitive and specific tool for prediction of hepatotoxicity secondary to acute acetaminophen overdose. By application of the APN, a significant proportion of patients may not require either further follow-up after the completion of NAC therapy or prolongation of NAC therapy. Patients in high APN's risk ranges may be treated and monitored more intensively with confidence.

Acetaminophen psi parameter: a useful tool to quantify hepatotoxicity risk in acute acetaminophen overdose.

CONTEXT: The risk of hepatotoxicity secondary to acute acetaminophen overdose is related to serum acetaminophen concentration and lag time from ingestion to N-acetylcysteine (NAC) therapy. Psi (Greek letter ψ) is a toxicokinetic parameter that takes the acetaminophen level at 4 h post-ingestion ([APAP](4 h)) and the time-to-initiation of NAC (tNAC) into account and was found to be significantly predictive of hepatotoxicity in Canadian patients with acetaminophen overdose treated with intravenous NAC. OBJECTIVE: We report the relationship of psi and hepatotoxicity in a Thai population with acute acetaminophen overdose. METHODS: This is a retrospective study of patients with acute paracetamol overdose during January 2004 to June 2009 at Siriraj Hospital. Patients were treated with the standard 21-h intravenous NAC regimen. Univariate analyses were performed with logistic regression to assess the relationships of psi, [APAP](4 h), and tNAC, and hepatotoxicity. RESULTS: A total of 127 patients were enrolled. The median (interquartile range; IQR) of [APAP](4 h) was 267.8 (196.0-380.0) mg/L. The median (IQR) of tNAC was 8.5 (6.2-12.0) h. Thirteen patients (10.2%) developed hepatotoxicity. Univariate analysis revealed [APAP](4 h), tNAC, and psi as statistically significant predictors of hepatotoxicity. DISCUSSION AND CONCLUSION: The psi parameter is a reliable prognostic tool to predict hepatotoxicity secondary to acute acetaminophen overdose treated with intravenous NAC. Our evidence shows that psi may be a more superior tool than either acetaminophen level or time-to-initiation of NAC at predicting hepatotoxicity.

Predictors of elevated blood lead level in Thai children: a pilot study using risk assessment questionnaire.

INTRODUCTION: In the era post leaded-gasoline use, the risk of exposure to environmental lead in Thai children is not well described. This is a pilot study using a risk assessment questionnaire to identify children with elevated blood lead level. MATERIAL AND METHOD: Children from 4 communities, 2 in the Bangkok metropolitan area and 2 in Kanchanaburi province, were recruited during their well child visits. Blood lead levels were obtained in all children and parents are asked to fill out a 25-item risk assessment questionnaire. STATISTICAL ANALYSIS: The relationship between the blood lead level and dependent variables were tested using linear regression and one-way analysis of variance (ANOVA) as appropriate. RESULTS: There were 296 children included in the study; 33 from Klong Toey and 114 from Siriraj community in Bangkok while 149 were from two different communities in Kanchanaburi province. The average blood lead level was 5.65 +/- 3.05 mcg/dL. The overall prevalence of children with blood lead level > 10 mcg/dL was 8.1%, while that of the Klong Toey community was 12.5%. The questionnaire identified 3 independent predictors of elevated blood lead levels; the presence of peeling paint in or outside the house, eating paints chips, and the geographic location of children. CONCLUSION: Using a risk assessment questionnaire, together with obtaining blood lead level has proven effective in identifying key environmental features associated with elevated blood lead level in children from sampled Thai communities. The challenge now is to conduct a larger epidemiological study of a similar type in order to guide the screening and preventive efforts.

Methamphetamine abuse during pregnancy and its health impact on neonates born at Siriraj Hospital, Bangkok, Thailand.

To ascertain the impact of intrauterine methamphetamine exposure on the overall health of newborn infants at Siriraj Hospital, Bangkok, Thailand, birth records of somatic growth parameters and neonatal withdrawal symptoms of 47 infants born to methamphetamine-abusing women during January 2001 to December 2001 were compared to 49 newborns whose mothers did not use methamphetamines during pregnancy. The data on somatic growth was analyzed using linear regression and multiple linear regression. The association between methamphetamine use and withdrawal symptoms was analyzed using the chi-square. Home visitation and maternal interview records were reviewed in order to assess for child-rearing attitude, and psychosocial parameters. Infants of methamphetamine-abusing mothers were found to have a significantly smaller gestational age-adjusted head circumference (regression coefficient = -1.458, p < 0.001) and birth weight (regression coefficient = -217.9, p < or = 0.001) measurements. Methamphetamine exposure was also associated with symptoms of agitation (5/47), vomiting (11/47) and tachypnea (12/47) when compared to the non-exposed group (p < 0r =0.001). Maternal interviews were conducted in 23 cases and showed that: 96% of the cases had inadequate prenatal care (<5 visits), 48% had at least one parent involved in prostitution, 39% of the mothers were unwilling to take their children home, and government or non-government support were provided in only 30% of the cases. In-utero methamphetamine exposure has been shown to adversely effect somatic growth of newborns and cause a variety of withdrawal-like symptoms. These infants are also psychosocially disadvantaged and are at greater risk for abuse and neglect.