Clinical characteristics, treatment and outcomes of acute propanil poisoning in a 7-year retrospective cohort study.

The present study was a 7-year retrospective cohort study (2012-2018) of patients treated for acute propanil poisoning by ingestion, using data from Ramathibodi Poison Center, Thailand. The aim of this study was to describe the clinical characteristics, treatment, outcomes and factors associated with moderate to severe outcomes and death following acute exposure to propanil. The effect of administering multiple-dose activated charcoal (MDAC) on clinical outcomes was also evaluated. A total of 275 cases were included. The results show that two thirds of patients were male and mean age was 40 years. Patients ingested either propanil or a mixture of propanil and other herbicides. The majority (98%) of exposures was intentional. Most patients (65.5%) presented with gastrointestinal symptoms. Methemoglobinemia and hemolysis were observed in 108 patients (39.3%) and 25 patients (9.1%), respectively. Median time to onset of methemoglobinemia and hemolysis after propanil ingestion was 5.5 and 48 h, respectively. One hundred and forty-one patients (51.3%) were treated with MDAC, and some patients received methylene blue (21.5%), intubation (18.5%), or blood transfusions (8%). All patients were admitted to hospitals. The median length of hospital stay of patients who survived was 3 days. Multivariate analysis indicated that neurological symptoms at presentation, methemoglobinemia and acute kidney injury during admission, were associated with moderate to severe outcomes. Factors associated with mortality were older age, larger amount of ingestion, neurological symptoms at presentation and hypotension during admission. The overall mortality rate was 6.2%. The mortality rate was 3.6% in patients that received MDAC and 9% in patients that did not, although the difference was not statistically significant. Subgroup analysis of patients who developed methemoglobinemia or both methemoglobinemia and hemolysis found a statistically significant lower mortality rate in patients that received MDAC. In conclusion, methemoglobinemia and hemolysis contribute to poor outcomes in acute propanil poisoning. Age, amount of ingestion, neurological symptoms at presentation and hypotension during admission could prognosticate deaths, and patients with these factors should be closely observed and aggressively managed.

Clinical effects and factors associated with adverse clinical outcomes of hymenopteran stings treated in a Thai Poison Centre: a retrospective cross-sectional study.

OBJECTIVE: To describe clinical effects and outcomes of hymenopteran stings and to explore the non-laboratory factors associated with adverse clinical outcomes, a composite outcome including death, respiratory failure requiring intubation, acute kidney injury (AKI) requiring dialysis and hypotension requiring vasopressor use. METHODS: A retrospective cross-sectional study was performed at the Ramathibodi Poison Center, a poison centre of a tertiary care hospital in Thailand. All cases of hymenopteran sting consultations from January 2015 to June 2019 were consecutively enrolled, and charts were reviewed. Demographics, initial clinical characteristics and outcomes were collected. Factors associated with adverse clinical outcome were explored. RESULTS: One hundred and fourteen hymenopteran stings cases (wasp 48%, bee 33%, hornet 14% and carpenter bee 8.8%) were included (median age, 36.5 years (interquartile range 9-55); male 63%). The prevalence of adverse clinical outcomes was 12.3% (95%CI 6.88-12.8). At initial presentation, 100% of cases had local skin reactions, 11.4% were clinical anaphylaxis, and 8% had red urine. Adverse clinical outcomes included death (n = 10), respiratory failure requiring intubation (n = 9), AKI requiring dialysis (n = 6) and hypotension requiring vasopressor use (n = 2). None of the patients with carpenter bee or hornet stings developed adverse clinical outcomes. In univariable analysis, urticaria, wheezing, red urine, wasp sting and sting number > 10 were significantly associated with adverse clinical outcomes. In multivariable analysis, red urine (adjusted OR 11.1 (95% CI 1.57-216)), wheezing (adjusted OR 16.7 (95% CI 1.43-402)) and a number of stings > 10 (adjusted OR 21.5 (95% CI2.13-2557)) were significant. CONCLUSIONS: Adverse clinical outcomes in hymenopteran stings were not uncommon among cases inquiring to a national Thai poison centre. At initial presentation, red urine, wheezing and a number stings >10 were significantly associated with adverse clinical outcomes. Larger epidemiologic studies are required to confirm these associations.

Acute Imidacloprid Poisoning in Thailand.

INTRODUCTION: Imidacloprid is the most commonly used neonicotinoid insecticide worldwide. Despite its reputation for safety, there is increasing evidence regarding its toxicity. This study characterized the clinical manifestations and outcomes of acute imidacloprid poisoning. METHODS: This was a retrospective study of patients with imidacloprid poisoning who were referred to the Ramathibodi Poison Center in Bangkok, Thailand between 2010 and 2018. RESULTS: A total of 163 patients with imidacloprid-only exposure were included. Most were exposed by ingestion (93.3%). The patients were predominantly male (55.8%), with a median age of 41.3 years. The common presenting features were gastrointestinal symptoms (63.8%) with no corrosive injuries and neurological effects (14.2%). The majority of medical outcomes was no (18.4%) to mild (76.1%) toxicity. One patient had symptoms mimicking cholinergic syndrome, three developed liver injury, and five died. Among the five deaths, two patients presented severe initial severity, and one presented moderate initial severity. Two of the patients who died initially presented only mild severity. The mortality rate was 3.1%. The estimated amount of ingestion, cardiovascular effects (especially tachycardia and cardiac arrest), central nervous system effects (especially coma), dyspnea, and diaphoresis were significantly associated with mortality. Patient management primarily included supportive and symptomatic care. CONCLUSION: Most patients with imidacloprid poisoning developed only mild toxicity. The mortality rate was low, but a few patients with mild initial severity died. Patients who ingest a large amount or show these warning signs including cardiovascular effects, central nervous system effects, dyspnea, and diaphoresis at the initial presentation should be considered for close observation and monitoring.

Clinical Characteristics of Acalypha indica Poisoning.

BACKGROUND: Acalypha indica is a tropical plant used as a herbal medicine in various parts of the world, including Thailand. In glucose-6-phosphate dehydrogenase (G6PD)-deficient patients, acute hemolysis has been reported following the ingestion of this plant. Methemoglobinemia was reported in the present study. PATIENTS AND METHODS: Descriptive data of patients who suffered from Acalypha indica toxicity reported from different hospitals to the Ramathibodi Poison Center were retrieved from 2011 to 2019. RESULTS: Eight patients were included, mostly male with a median age of 61.5 years. The plant was ground for fresh juice or boiled before consuming as herbal medicine. All patients presented with dark urine. Most had jaundice and fever, and all reported hemolysis. Seven out of eight patients were diagnosed as methemoglobinemia. Methemoglobin level was confirmed in five patients with the highest level of 23.9%. Early symptoms occurred within 24 hours of the last ingested dose. DISCUSSION: In previous case reports of Acalypha indica ingestion, acute hemolysis was mostly observed in G6PD-deficient patients, consistent with the current findings. However, our patients also demonstrated methemoglobinemia, with some constituents in this plant (quinine, 2-methyl anthraquinone and tectoquinone) implicated as the cause in previous studies. Further studies are crucial to validate these findings. CONCLUSION: We report a case series in which acute hemolysis and methemoglobinemia after Acalypha indica ingestion were observed. This study presents methemoglobinemia as the other toxicity caused by this plant.

Hematotoxic Manifestations and Management of Green Pit Viper Bites in Thailand.

INTRODUCTION: Green pit vipers (GPV) are widely distributed throughout Thailand and are responsible for significant morbidity. The primary objective of this study was to characterize clinical presentations and treatment methods for GPV bites. The secondary objective was to demonstrate the earliest and latest onset of hematotoxicity. METHODS: GPV bites reported to the Ramathibodi Poison Center between July 1, 2016, and June 30, 2018, were analyzed. RESULTS: There were 288 GPV cases within the study period. Patients were predominantly male (62.8%), and the median age was 40 years (interquartile range (IQR) 22.8-58). Median time from envenomation to hospital presentation was 1 hour (IQR 0.5-2). Patients were primarily bitten on the finger (27.4%). Most patients reported swelling (90.3%). Necrosis and compartment syndrome occurred in 13 and 9 cases, respectively. Systemic effects occurred in 190 cases (65.9%), with median onset 15 hours (IQR 6-28.3) post-bite. Venous clotting time (VCT) showed the highest percentage of abnormalities. Systemic bleeding occurred in 13 cases (4.5%). Monitoring patients for 24, 48, and 72 hours after bites detected 62.7%, 85.9%, and 96.5% of cases with systemic effects, respectively. In total, 184 patients (62.5%) were treated, sometimes repeatedly, with antivenoms (285 courses, 949 vials). The most common indication was prolonged VCT (144 courses, 50.5%). Recurrent systemic effects after antivenom occurred in 11 cases (6.1% of patients received antivenom). No recurrence presented as systemic bleeding. Adverse reactions to antivenom were reported in 44 courses (15.4% of 285 courses), being anaphylaxis in 19 courses (6.7%). Other treatments included antibiotics (192 cases, 66.7%), surgical intervention (10, 34.7%), and blood components (4, 1.4%). CONCLUSION: Most GPV bites result in envenomation. The most frequent local effect is mild swelling. Systemic bleeding is uncommon. The current recommendation of a 3-day follow-up can detect up to 96% of patients who may require antivenom. No severe morbidity or mortality is reported. Antivenoms are primarily indicated by prolonged VCT. Side effects of antivenom are minimal.

Krait envenomation in Thailand.

PURPOSE: Three species in the genus Bungarus inhabit Thailand. Among these, Bungarus candidus (Malayan krait) is the most common and deadliest. Currently, the clinical manifestations of patients envenomed by kraits, especially Bungarus fasciatus (banded krait), have not been thoroughly investigated. This study was performed to elucidate the clinical manifestations and outcomes of patients bitten by kraits in Thailand. MATERIALS AND METHODS: The data of krait envenomation cases that occurred during a 9-year period were obtained from the Ramathibodi Poison Center Toxic Exposure Surveillance System and retrospectively analyzed. RESULTS: In total, 78 cases of krait envenomation were included. Most patients were male (59.0%) and the median age was 28 years. All had minimal local effects. The median duration from the bite to the onset of neurological manifestations was 3 hours (range, 0.5-8 hours). Besides neurological effects, the patients also developed high blood pressure (67.4%), tachycardia (61.7%), hypokalemia (55.3%), and hyponatremia (17.6%). Severe hyponatremia (<120 mEq/L) was noted in four pediatric patients. Other clinical manifestations were bradycardia, abdominal pain, and rhabdomyolysis. The mortality rate was 6.4%, and all deaths occurred from B. candidus bites. Eighty-six percent of patients received antivenom. Most patients (75.6%) were intubated and underwent assisted ventilation for a median of 6 days (range, 1-37 days). The median length of hospital stay was 7 days. Some patients developed complications during hospitalization; the most common was pneumonia. These in-hospital complications were significantly associated with death. CONCLUSION: Although krait bites caused only minimal local effects, the mortality rate was still high, particularly from Malayan krait bites. Besides neurological effects, other clinical manifestations were high blood pressure, tachycardia, hypokalemia, and hyponatremia. Thus, vital signs and electrolytes should be frequently and closely monitored in these patients. Apart from antivenom treatment, adequate supportive care including management of complications might help to decrease the mortality rate.

Cyanide poisoning in Thailand before and after establishment of the National Antidote Project.

CONTEXT: Antidote shortage is a global problem. In Thailand, the National Antidote Project (NAP) has operated since November 2010 to manage the national antidote stockpile, educate the healthcare providers on appropriate antidote use, and evaluate antidote usage. OBJECTIVE: To evaluate the effect of NAP implementation on mortality rate and antidote use in cyanide poisoning cases arising from ingestion of cyanide or cyanogenic glycoside. METHODS: This is a retrospective cohort of poisoning cases involving cyanide or cyanogenic glycoside ingestion reported to Ramathibodi Poison Center from 1 January 2007 to 31 December 2015. Mortality rate, antidote use, and appropriateness of antidote use (defined as correct indication, proper dosing regimen, and administration within 90 min) before and after NAP implementation were compared. Association between parameters and fatal outcomes was analyzed. RESULTS: A total of 343 cases involving cyanide or cyanogenic glycoside ingestion were reported to Ramathibodi Poison Center. There were 213 cases (62.1%) during NAP (Project group) and 130 cases (37.9%) pre-NAP implementation (Before group). Implementation of NAP led to increased antidote use (39.9% in Project group versus 24.6% in Before group) and a higher rate of appropriate antidote use (74.1% in Project group versus 50.0% in Before group). All 30 deaths were presented with initial severe symptoms. Cyanide chemical source and self-harm intent were associated with death (OR: 12.919, 95% CI: 4.863-39.761 and OR: 10.747, 95% CI: 3.884-28.514, respectively). No difference in overall mortality rate (13 [10.0%] deaths before versus 17 [8.0%] deaths after NAP) was found. In subgroup analysis of 80 cases with initial severe symptoms, NAP and appropriate antidote use reduced mortality (OR: 0.327, 95% CI: 0.106-0.997 and OR: 0.024, 95% CI: 0.004-0.122, respectively). In the multivariate analysis of the cases with initial severe symptoms, presence of the NAP and appropriate antidote use independently reduced the risk of death (OR: 0.122, 95% CI: 0.023-0.633 and OR: 0.034, 95% CI: 0.007-0.167, respectively), adjusted for intent of exposure, cyanide source, age, and sex. CONCLUSIONS: After NAP implementation, both antidote use and appropriate antidote use increased. In cases presenting with severe symptoms, presence of the NAP and appropriate antidote use independently reduced the risk of mortality.