Question of the Day – Friday, October 14, 2022
What is the treatment for chronic toxicity from nitrous oxide abuse? High dose intramuscular vitamin B12 supplementation. A typical regimen is 1000 mcg IM daily for 14 days, followed by 1000 mcg IM weekly for four weeks, and then extended to monthly. Cyanocobalamin has generally…
Question of the Day – Thursday, October 13, 2022
Patients with subacute combined spinal cord degeneration (SCD) from chronic nitrous oxide abuse will often have elevated levels of methylmalonic acid and homocysteine. Which is more specific for B12 deficiency? MMA elevation is more specific for B12 deficiency because homocysteine may be elevated with folate…
Question of the Day – Wednesday, October 12, 2022
At what time of year do cyclopeptide containing mushrooms typically grow? June-November. Mushrooms can be found at the base of deciduous trees, such as oak trees. Moor-Smith M. The world’s most poisonous mushroom, Amanita phalloides, is growing in BC. BCMJ 2019;61(1): 20-24.
Question of the Day – Tuesday, October 11, 2022
What is the proposed mechanism of action for polymixin B in cyclopeptide mushroom poisoning? Binding to RNA polymerase II, preventing a-Amanitin binding and inhibition of protein synthesis. The suggested dose of 0.75 mg/kg (7,500 units/kg) is lower than typical doses used for antibiosis and is…
Question of the Day – Monday, October 10, 2022
What is the proposed mechanism of action for N-acetylcysteine in cyclopeptide mushroom poisoning? Non-specific hepatoprotective effects due to free radical scavenging and glutathione repletion and is typically recommended to be administered using the standard IV NAC regimen. Ye Y. Management of Amanita phalloides poisoning: A…
Question of the Day – Friday, October 7, 2022
Nitrous oxide causes a functional vitamin B12 deficiency by what mechanism? Irreversible oxidation of the central cobalt ion from its monovalent to divalent state, rendering B12 inactive. Methylcobalamin and adenosylcobalamin, the activated forms of Vitamin B12, are necessary cofactors for two essential enzymes involved in…
Question of the Day – Thursday, October 6, 2022
According to a recent retrospective analysis of prospectively collected data from patients with snakebite reported to the ToxIC North American Snakebite Registry, crotalidae immune F(ab’)2 (equine) was superior to crotalidae immune polyvalent Fab (ovine) in preventing what sequelae of North American rattlesnake envenomation? Late hemotoxicity….
Question of the Day – Wednesday, October 5, 2022
According to a recent systematic review of ethylene glycol poisoning, what was the glycol concentration that best predicted acute kidney injury? AKI was expected if the glycolate concentration was >12.9 mmol/L, (sensitivity 78.5%, specificity 88.1%, positive predictive value 86.4%, negative predictive value 80.9%). This correlated…
Question of the Day – Tuesday, October 4, 2022
What is the proposed mechanism of action for silibinin in cyclopeptide mushroom poisoning? Reduced enterohepatic recirculation and uptake into hepatocytes through organic anion-transporter (OAT) inhibition. Ye Y. Management of Amanita phalloides poisoning: A literature review and update. J Crit Care. 2018;46:17-22. doi: 10.1016/j.jcrc.2018.03.028.
Question of the Day – Monday, October 3, 2022
What is the proposed mechanism of action for penicillin G in cyclopeptide mushroom poisoning? Prevention of a-Amanitin uptake into hepatocytes via organic anion-transporter polypeptide 1B3 (OATP1B3) inhibition. The suggested dose of 1 MU/kg/day is at least 2-3 times higher than doses typically used for antibiosis….