Poisoning by illegal rodenticides containing acetylcholinesterase inhibitors (chumbinho): a prospective case series

Pesticide exposure and poisoning in Brazil: Outcome severity, clinical manifestations and management of cases reported to a poison control center

This work aimed to identify variables associated with increased risk of outcome severity as well as to describe clinical manifestations/symptoms and management of pesticide-related cases reported to a poison center in Brazil. An increased risk of more severe outcomes was observed when exposures occurred in rural areas, involved suicide attempts and moderately to extremely hazardous pesticides. Clinical manifestations with higher frequencies included vomiting, nausea, sialorrhea, headache, miosis and sweating. From the treatment initially applied to the patient, 51.91% encompassed gastric lavage, but this procedure was only recommended in 20.01% of cases by the CIATox. Identifying risk factors associated with poor outcome, describing clinical manifestations, and contrasting initial treatment measures adopted against those recommended by the Poison Center can help determine diagnosis, prognosis and ensure appropriate clinical interventions are used in cases of pesticide poisoning.

Prognostic factors in acute poisoning with central nervous system xenobiotics: development of a nomogram predicting risk of intensive care unit admission

Background

Acute intoxication with central nervous system (CNS) xenobiotics is an increasing global problem. Predicting the prognosis of acute toxic exposure among patients can significantly alter the morbidity and mortality. The present study outlined the early risk predictors among patients diagnosed with acute exposure to CNS xenobiotics and endorsed bedside nomograms for identifying patients requiring intensive care unit (ICU) admission and those at risk of poor prognosis or death.

Methods

This study is a 6-year retrospective cohort study conducted among patients presented with acute exposure to CNS xenobiotics.

Results

A total of 143 patients' records were included, where (36.4%) were admitted to the ICU, and a significant proportion of which was due to exposure to alcohols, sedative hypnotics, psychotropic, and antidepressants (P = 0.021). ICU admission was associated with significantly lower blood pressure, pH, and HCO₃ levels and higher random blood glucose (RBG), serum urea, and creatinine levels (P < 0.05). The study findings indicate that the decision of ICU admission could be determined using a nomogram combining the initial HCO₃ level, blood pH, modified PSS, and GCS. HCO₃ level < 17.1 mEq/L, pH < 7.2, moderate-to-severe PSS, and GCS < 11 significantly predicted ICU admission. Moreover, high PSS and low HCO₃ levels significantly predicted poor prognosis and mortality. Hyperglycemia was another significant predictor of mortality. Combining initial GCS, RBG level, and HCO₃ is substantially helpful in predicting the need for ICU admission in acute alcohol intoxication.

Conclusion

The proposed nomograms yielded significant straightforward and reliable prognostic outcomes predictors in acute exposure to CNS xenobiotics.

Drugs, pesticides and metabolites in forensic post-mortem blood samples

Forensic post-mortem toxicological data provide valuable information for the elucidation of cause of death. However, this is still not routine practice in Brazilian laboratories. This study investigated the presence of illicit and prescription drugs, pesticides and metabolites in 111 post-mortem blood samples from cases investigated by the Forensic Medical Institute of the Federal District, Brazil. Quantitative analysis was performed for 14 analytes using a validated programmed temperature vaporisation-large volume injection-gas chromatography-mass spectrometry method, which was also used as screening (qualitative analysis) for an additional 19 substances of forensic interest. At least one analyte was found in 61.2% of the samples, of which 34 were related to homicide, 15 to accidental death and 10 to suicide cases. The victims were 14-72 years old. The benzodiazepines diazepam, midazolam and 7-aminoflunitrazepan were detected in 46% of the positive samples (0.02-1.12 µg/mL; midazolam only qualitative). Cocaine was found in 34% (0.02-4.07 µg/mL), associated with substances commonly used as cocaine adulterants (e.g. caffeine, lidocaine and phenacetin). Three suicide cases involved the illegal rodenticide chumbinho, residues of which were found in the gastric content, and blood samples showed the presence of terbufos (0.03 and 0.04 µg/mL) and carbofuran (27.3 µg/mL). These results are discussed, along with autopsy and crime-scene information.

Sociodemographic characteristics and exposure patterns of pesticide-related cases reported to a poison service center in Brazil between 2012 and 2016

Pesticide poisoning is a significant public health problem responsible for an estimated three million poisoning cases per year and more than 250,000 deaths, most of which occur in underdeveloped countries. We evaluated pesticide exposure cases reported to a toxicological service center in Brazil, between 2012 and 2016. There were 3211 cases of pesticide exposure, with a high prevalence in adults aged 20-39 years (41.2%). Attempted suicide was the leading cause of pesticide cases (48%). Occupational exposure to pesticides of agricultural use was more frequently observed among men. Accidental exposure and attempted suicide were more frequently observed in urban areas while occupational exposure was more prevalent in rural areas. A higher exposure rate was observed among men in counties with higher agricultural activities. Establishing prevalence and cause of pesticide exposure is important to provide subsidy for evidence-based interventions in the field.

SEVERE ACUTE TOXIC EXPOSURES IN CHILDREN AND ADOLESCENTS: CASE SERIES

OBJECTIVE

To describe a case series of severe acute toxic exposures (SATE) in individuals <20 years old followed-up by a regional Poison Control Center (PCC).

METHODS

Descriptive cross-sectional study. All patients who were <20yo and classified as score 3 (severe) and 4 (fatal) following Poisoning Severity Score were included for analysis. According to the outcome, patients were classified as PSS 3 when they developed intense clinical manifestations with risk of death or important sequelae; and as PSS 4 when death had resulted from direct cause or complication of the initial exposure. The data of patients were obtained from the Brazilian electronic database system (DATATOX).

RESULTS

During the biennium 2014-2015, Campinas PCC followed up 5,095 patients <20yo, with 30 being classified as SATE (PSS=3, n=24; PSS=4, n=6). The exposures circumstances were unintentional (15); intentional (14; suicide attempt = 11; street drugs consumption = 3); and not explained (1). The exposures were significantly more frequent in adolescents >14yo (n=17; p<0.01). The involved agents were venomous animals (8; scorpions=5); medicines (8; miscellaneous=6); chemicals (6); illegal rodenticides containing acetylcholinesterase inhibitors (chumbinho, 4); drugs of abuse (3); button battery (1). Three patients evolved with sequels (esophageal stricture post-corrosive ingestion). The median length of hospital stay was 6 days (IQR: 5-12 days); 26 patients were treated in intensive care units, and 22 of them needed mechanical ventilation; 12, inotropic/vasopressors; and 3, renal replacement therapy.

CONCLUSIONS

Scorpion stings and poisonings caused by medicines and chemicals were the main causes of SATE. The SATE were significantly more frequent in adolescents, due to deliberate self-poisoning.

Multivariate analysis applied in dataset of Poison Control Center of São Paulo, Brazil

Multivariate analysis techniques could be used to identify possible intercorrelations in intoxications cases. The statistical analyses used were a multiple logistic regression, multiple correspondence analysis, principal component and hierarchical cluster analysis. Of the 320 samples analysed, 192 samples were positive for some of the investigated toxic agents, of which 100 were positive for ethanol and 131 were positive for other substances. It was possible to group the patients into 3 clusters, which appears 66.5% of this information in the three first factorial axes. On the first axis, the male patients were separated from the female patients. Patients exposed to drugs, between 30 and 39 years old were grouped in the same cluster. On the second factorial axis, patients who were intoxicated with ethanol and who became intoxicated with diazepam were grouped. This work contributed to the mapping of intoxication cases at the Poison Control Centre of the São Paulo city, Brazil (CCI-SP) and serves as an initial study for the creation of a database that could be updated constantly and thus could provide a toxicovigilance system for educational policies.

Two health information systems to characterize poisoning in Brazil-a descriptive study

BACKGROUND

Poisoning is a worldwide public health problem that involves individuals of all ages and a wide range of chemicals. This study investigated the data from two health information systems to characterize poisoning events in the Federal District (DF), Brazil.

METHODS

Data related to the period from 2009 to 2013 were obtained from the poison information center (Centro de Informação Toxicológica, CIT) and the Notifiable Diseases Information System (Sistema Nacional de Agravos de Notificação, SINAN) of the DF.

RESULTS

A total of 3622 cases were reported to CIT-DF and 5702 cases to SINAN-DF. Most of the cases in CIT-DF (53%) occurred with children up to 9 years old, while this corresponded to 33.9% in SINAN-DF. Unintentional poisoning was the main circumstance involved in the cases. Pharmaceuticals were the main agent (44.3-47.1% of the cases), mainly clonazepan and paracetamol, and pesticides the most fatal (2.4% fatality rate). Out of the 47 fatal cases reported to the systems, only four were reported to both; six cases occurred with children up to 6 years.

CONCLUSION

Under-reporting and missing information were identified in both systems, but the data were complementary to describe the epidemiology of poisoning cases in the DF.

Should We Be Using the Poisoning Severity Score?

INTRODUCTION

Despite the existence of a number of severity-of-illness classifications for other areas of medicine, toxicology research lacks a well-accepted method for assessing the severity of poisoning. The Poisoning Severity Score (PSS) was developed in the 1990s in Europe as a scoring system for poisonings reported to a poison center in order to describe a patient's most severe symptomatology. We reviewed the literature to describe how the PSS is utilized and describe its limitations.

DISCUSSION

We searched the medical literature in all languages using PUBMED, EMBASE, and SCOPUS from inception through August 2013 using predefined search terms. Out of 204 eligible publications, 40 met our criteria for inclusion in this review. There has been a paucity of published studies from North America that used the PSS. In some cases,  the PSS was misapplied or modified from standard scoring, making a bottom line appraisal of the validity or reliability of the original version of the instrument challenging. The PSS has several subjective criteria, is time consuming to score, and is likely to be of little use with some types of poisonings, limiting its clinical utility.

CONCLUSION

The PSS was developed as a tool to document encounters with poisoned patients. However, it is used infrequently and, when applied, has been misused or modified from its original form. In its current form, it has limited clinical utility and likely cannot be broadly applied to many exposures due to their unique clinical circumstances. With better global collaboration among medical toxicologists, it is possible that a modified score could be developed for use clinically or as a research instrument.

EXPOSIÇÕES TÓXICAS EM CRIANÇAS A SANEANTES DE USO DOMICILIAR DE VENDA LEGAL E CLANDESTINA

Objectives:

To analyze and to compare clinical repercussions of accidents involving legally and illegally commercialized household sanitizers in children under 7 years of age.

Methods:

A descriptive cross-sectional design was used to collect data from electronic database of a regional Poison Control Center during one year. Data were analyzed by means of descriptive non-parametric statistics and association tests.

Results: The sample had 737 reported cases. Most of the accidents occurred with children under 3 years of age (median: 1 year of age; interquartile interval: 1-3 years of age), at home (92.9%), by ingestion (97.2%). Products involved were cleaning products with low toxicity and no caustic effects (38.9%); caustics (24.1%); hydrocarbons (19.3%); pesticides/rodenticides (16.6%), and other products (1.1%). Seventy accidents were due to exposures to illegal products, mainly caustics (n=47) and rodenticides (n=15). Among the 337 children presenting post-exposure clinical manifestations, the most frequent were vomiting (n=125), oral burns (n=74), cough (n=35), drooling (n=26), and abdominal pain (n=25). Clinical manifestations were significantly more frequent after illegal products exposure (55/70 versus 282/667, p<0.01). Nineteen children had to be hospitalized (caustics, n=17; illegal products, n=12; median time of hospitalization: 2 days), 22 were submitted to esophagogastroduodenoscopy (sodium hydroxide, n=14; illegal products, n=14); and 12 cases had endoscopic alterations (severe in 2). No deaths occurred.

Conclusion:

Toxic exposures owing to illegal household sanitizer products are associated with greater morbidity when compared with legal ones.

Postponed effect of neostigmine on oxidative homeostasis

Cholinesterases are enzymes able to hydrolyze the neurotransmitter acetylcholine and thus to terminate transmission. Once the enzymes are inhibited, excitotoxicity can appear in the adjacent cells. It is well known that oxidative stress is involved in the toxicity of cholinesterase inhibitors. Commonly, stress follows inhibition of cholinesterases and disappears shortly afterwards. In the present experiment, it was decided to test the impact of an inhibitor, neostigmine, on oxidative stress in BALB/c mice after a longer interval. The animals were sacrificed three days after onset of the experiment and spleens and livers were collected. Reduced glutathione (GSH), glutathione reductase (GR), glutathione S-transferase (GST), thiobarbituric acid reactive substances (TBARS), ferric reducing antioxidant power (FRAP), caspase-3 and activity of acetylcholinesterase (AChE) were assayed. The tested markers were not altered with exceptions of FRAP. The FRAP values indicate accumulation of low molecular weight antioxidants in the examined organs. The role of low molecular weight antioxidants in the toxicity of AChE inhibitors is discussed.

Biosensors containing acetylcholinesterase and butyrylcholinesterase as recognition tools for detection of various compounds

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are enzymes expressed in the human body under physiological conditions. AChE is an important part of the cholinergic nerves where it hydrolyses neurotransmitter acetylcholine. Both cholinesterases are sensitive to inhibitors acting as neurotoxic compounds. In analytical applications, the enzymes can serve as a biorecognition element in biosensors as well as simple disposable sensors (dipsticks) and be used for assaying the neurotoxic compounds. In the present review, the mechanism of AChE and BChE inhibition by disparate compounds is explained and methods for assaying the enzymes activity are shown. Optical, electrochemical, and piezoelectric biosensors are described. Attention is also given to the application of sol-gel techniques and quantum dots in the biosensors’ construction. Examples of the biosensors are provided and the pros and cons are discussed.