monocrotophos and Organophosphate-Poisoning

Munchausen syndrome by proxy is a form of abuse in which an adult, usually the mother, deceives health workers by exaggerating, falsifying or directly inducing psychological or physical symptoms in the child victim for psychological gratification. In 2013, the American Academy of Pediatrics coined the term 'caregiver-fabricated illness in a child' to describe this form of child abuse. A 7-year-old girl had many encounters with health workers over a period of 4 years and presented with evolving clinical features including refractory seizures and red urine for which she was followed up as a case of acute intermittent porphyria. She was later discovered to be the victim of chronic monocrotophos organophosphate poisoning by her mother. If all medical staff who manage children are to avoid becoming inadvertent participants in medical child abuse, this case report is an important reminder that a high index of suspicion is warranted in cases which present a diagnostic dilemma and who respond unexpectedly to treatment.

Topics: Adult; Anistreplase; Child; Female; Humans; Infant, Newborn; Insecticides; Monocrotophos; Mothers; Munchausen Syndrome by Proxy; Organophosphate Poisoning; Porphyria, Acute Intermittent

Monocrotophos, implicated in about 1/4th of organophosphate poisonings in our centre, is associated with the highest mortality (24%). Yet data on its pharmacokinetics in humans is limited. We estimated the renal elimination half-life of monocrotophos.. Consecutive patients presenting with monocrotophos overdose over a 2-month period who had normal renal function were recruited. Monocrotophos in plasma and urine were quantitated by high-performance liquid chromatography. Urine was obtained from catheterised samples at 0-2, 2-4, 4-6, 6-8, 8-12 and 12-24 h. Plasma specimens were collected at the time of admission, and at the midpoint of the urine sample collections at 1, 3, 5, 7, 10, 15 and 21 h. Renal elimination half-life was calculated from the cumulative amount excreted in the urine.. The cohort of 5 male patients, aged 35.8 ± 2.94 years, presented with typical organophosphate (cholinergic) toxidrome following intentional monocrotophos overdose. All patients required mechanical ventilation; one patient died. Plasma data was available from 5 patients and urine data from 3 patients. The median renal elimination half-life was 3.3 (range: 1.9-5.0 h). Plasma monocrotophos values, as natural log, fell in a linear fashion up to around 10 h after admission. After the 10-hour period, there was a secondary rise in values in all the 3 patients in whom sampling was continued after 10 h.. A renal elimination half-life of 3.3 h for monocrotophos is consistent with a water-soluble compound which is rapidly cleared from the plasma. The secondary rise in plasma monocrotophos values suggests possible re-distribution. Determining the elimination profile of this compound will help develop better strategies for treatment.

Topics: Adult; Chromatography, High Pressure Liquid; Half-Life; Humans; Intensive Care Units; Kidney; Male; Monocrotophos; Organophosphate Poisoning; Renal Elimination; Specimen Handling

Topics: Child; Cholinesterase Inhibitors; Food Contamination; Humans; India; Insecticides; Monocrotophos; Organophosphate Poisoning; Schools; Toxicity Tests

Clinical scoring systems are used to predict mortality rate in hospitalized patients. Their utility in organophosphate (OP) poisoning has not been well studied.. In this retrospective study of 396 patients, we evaluated the performance of the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the Simplified Acute Physiology Score (SAPS) II, Mortality Prediction Model (MPM) II, and the Poisoning Severity Score (PSS). Demographic, laboratory, and survival data were recorded. Receiver operating characteristic (ROC) curves were generated, and the area under the curve (AUC) was calculated to study the relationship between individual scores and mortality rate.. The mean (standard deviation) age of the patients was 31.4 (12.7) years, and at admission, their pseudocholinesterase (median, interquartile) level was 317 (222-635) U/L. Mechanical ventilation was required in 65.7% of the patients and the overall mortality rate was 13.1%. The mean (95% confidence interval) scores were as follows: APACHE-II score, 16.4 (15.5-17.3); SAPS-II, 34.4 (32.5-36.2); MPM-II score, 28.6 (25.7-31.5); and PSS, 2.4 (2.3-2.5). Overall, the AUC for mortality was significantly higher for APACHE-II (0.77) and SAPS-II (0.77) than the PSS (0.67). When patients were categorized, the AUCs were better for WHO Class II (0.71-0.82) than that for Class I compounds (0.60-0.66). For individual compounds, the AUC for APACHE-II was highest in quinalphos (0.93, n = 46) and chlorpyrifos (0.86, n = 38) and lowest in monocrotophos (0.60, n = 63). AUCs for SAPS-II and MPM-II were marginally but not significantly lower than those for APACHE-II. The PSS was generally a poorer discriminator compared to the other scoring systems across all categories.. In acute OP poisoning, the generic scoring systems APACHE-II and SAPS-II outperform the PSS. These tools may be used to predict the mortality rate in OP poisoning.

Topics: Adult; APACHE; Chlorpyrifos; Cholinesterase Inhibitors; Cohort Studies; Health Status Indicators; Hospitals, Religious; Hospitals, University; Humans; India; Insecticides; Medical Records; Monocrotophos; Organophosphate Poisoning; Organothiophosphorus Compounds; Prognosis; Retrospective Studies; ROC Curve; Severity of Illness Index; Young Adult

Several episodes of mass poisoning by organophosphates (OPs) have been reported from the developing countries. The diagnosis of OP-poisoning is mainly based on the characteristic clinical features and history of exposure to a known OP compound. Estimation of serum and red blood cell (RBC) cholinesterase activities are helpful in confirming the diagnosis. However, there is controversy regarding a definite relationship between serum cholinesterase activity and the severity of clinical manifestations and prognosis. This report describes an episode of mass monocrotophos poisoning that occurred due to accidental ingestion of monocrotophos-contaminated millet (so-called bavta) flour involving eight severely poisoned persons. Clinical presentation included severe abdominal pain, diarrhoea, vomiting, pupil narrowing, and difficulty breathing. On hospital admission, plasma cholinesterase (PChE) and especially RBC acetylcholinesterase (AChE) activities correlated well with clinical symptoms presented by the patients. This case study highlights the need for clinicians to be aware of OP-pesticide poisoning from food sources and the need to look for depressed PChE and AChE activities that may point to OP exposure, so that OP-poisoning can be identified immediately and patients can receive specific treatment, rather than general treatment for food poisoning.

Topics: Adolescent; Adult; Child; Diarrhea; Dyspnea; Female; Flour; Food Contamination; Foodborne Diseases; Humans; India; Insecticides; Male; Middle Aged; Monocrotophos; Organophosphate Poisoning; Pain; Respiratory Insufficiency; Sialorrhea; Vomiting

The aim of the study was to examine antidotal potency of trimedoxime in mice poisoned with three direct dimethoxy-substituted organophosphorus inhibitors. In order to assess the protective efficacy of trimedoxime against dichlorvos, heptenophos or monocrotophos, median effective doses and efficacy half-times were calculated. Trimedoxime (24 mg/kg intravenously) was injected 5 min. before 1.3 LD50 intravenously of poisons. Activities of brain, diaphragmal and erythrocyte acetylcholinesterase, as well as of plasma carboxylesterases were determined at different time intervals (10, 40 and 60 min.) after administration of the antidotes. Protective effect of trimedoxime decreased according to the following order: monocrotophos > heptenophos > dichlorvos. Administration of the oxime produced a significant reactivation of central and peripheral acetylcholinesterase inhibited with dichlorvos and heptenophos, with the exception of erythrocyte acetylcholinesterase inhibited by heptenophos. Surprisingly, trimedoxime did not induce reactivation of monocrotophos-inhibited acetylcholinesterase in any of the tissues tested. These organophosphorus compounds produced a significant inhibition of plasma carboxylesterase activity, while administration of trimedoxime led to regeneration of the enzyme activity. The same dose of trimedoxime assured survival of experimental animals poisoned by all three organophosphorus compounds, although the biochemical findings were quite different.

Topics: Acetylcholine; Animals; Brain Chemistry; Carboxylesterase; Diaphragm; Dichlorvos; Drug Evaluation, Preclinical; Erythrocytes; Injections, Intravenous; Lethal Dose 50; Male; Mice; Monocrotophos; Organophosphate Poisoning; Organophosphorus Compounds; Oximes; Time Factors; Trimedoxime

Topics: Adult; Atropine; Cholinesterase Inhibitors; Cholinesterase Reactivators; Dichlorvos; Female; Humans; Insecticides; Male; Monocrotophos; Muscarinic Antagonists; Neurotoxicity Syndromes; Organophosphate Poisoning; Pralidoxime Compounds; Suicide, Attempted