Evaluation of Strontium Interference in Calcium Measurement Procedures and Content in Supplements as Measured by ICP-MS.

BACKGROUND: Bone health supplements containing strontium are available without prescription, however, the effects of strontium interference on clinical laboratory calcium measurement procedures are unknown. METHODS: To evaluate strontium interference on total calcium measurements, plasma pools with exogenously added strontium were measured by 3 total calcium measurement procedures. For ionized calcium measurements, whole blood pools prepared with exogenously added strontium were measured by 2 ionized calcium measurement procedures. An inductively coupled plasma mass spectrometry assay (ICP-MS) was validated for research measurements of strontium content in commercially available supplements. RESULTS: Exogenous strontium addition to plasma caused positive bias for total calcium measurements. Strontium concentrations of 1.0 mg/dL (0.114 mmol/L), 2.5 mg/dL (0.284 mmol/L), and 5.0 mg/Dl (0.568 mmol/L) resulted in mean biases of 1.9% to 3.5%, 4.9% to 9.0%, and 10.8% to 19.2%, respectively, for total calcium measurement procedures. Biases for ionized calcium measurements were less than 4.5% for a strontium concentration of 5.0 mg/dL (0.568 mmol/L). An in-house-developed ICP-MS assay for strontium in commercially available supplements exhibited within-laboratory and within-run coefficients of variation of less than 3%, and a linear response was obtained over the assay analytical measurement range of 10 to 100 000 ng/mL (0.0001 to 1.141 mmol/L). Strontium recovery for the ICP-MS assay was 97.1% to 105.3%. The largest amount of strontium measured in dietary supplements was 395 mg in a 1054 mg tablet. CONCLUSIONS: Some dietary supplements contain larger amounts of strontium than indicated on the product label. High concentrations of strontium may cause significant interference for total calcium measurement procedures, but ionized calcium measurement procedures are not significantly affected.

Negligible Nux Vomica: Homeopathic Nux Vomica remedies don't contain strychnine?

INTRODUCTION: The St. Ignatius bean of the Strychnos ignatii tree and Nux Vomica homeopathic products presumably could contain the toxic alkaloids strychnine and brucine. This study aimed to determine the amount of these toxic alkaloids in some commercially available Nux Vomica products and the St. Ignatius bean and to determine if overdose of these products could result in clinically significant toxicity. METHODS: Using ultra-performance liquid chromatography-tandem mass spectrometry, various formulations of Nux Vomica products and St. Ignatius beans were analyzed for strychnine, and brucine with detection limits set at 0.1 ng/g. RESULTS: None of the analyzed Nux Vomica products contained any detectable strychnine or brucine, while the expected strychnine dose from a St. Ignatius bean would be < 0.001 mg. CONCLUSIONS: Overall, our study reveals that the amount of strychnine in homeopathic Nux Vomica products or St. Ignatius beans are not likely to result in clinically significant strychnine toxicity.

Outbreak of Severe Hypoglycemia After Ingestion of a Male Enhancement Supplement - Virginia, August-November 2019.

In August 2019, the Virginia Poison Center (VPC) and the Blue Ridge Poison Center (BRPC) were contacted concerning patients experiencing repeated episodes of marked hypoglycemia following ingestion of a male enhancement supplement tablet marketed as "V8" in convenience stores in central Virginia. Over the following 3 months, the Virginia Department of Agriculture and Consumer Services (VDACS) and the Virginia Department of Health (VDH) conducted an investigation and identified 17 patients meeting the case definition (severe hypoglycemia within 48 hours of consuming an over-the-counter male enhancement supplement in a man with no history of use of insulin or other medication used to control blood glucose). Analysis of the V8 tablets revealed that most contained glyburide, a sulfonylurea oral hypoglycemic used in the treatment of diabetes and associated with prolonged hypoglycemia following overdose (1). To stem this outbreak, V8 was removed from stores when found, and public service announcements were released. The public health implications of V8 use include the potential for substantial morbidity from hypoglycemic episodes and the potential for mortality if health care services are not accessed in a timely manner when hypoglycemia occurs. The presence of V8 in the market poses a serious threat to public health because of its potentially life-threatening adverse effects.

Survival After Cardiac Arrest: ECMO Rescue Therapy After Amlodipine and Metoprolol Overdose.

Extracorporeal membrane oxygenation (ECMO) use in poisoned patients is increasing, but is rare post cardiac arrest. We report a case of ECMO use with complete recovery in a patient who arrested twice after a cardiotoxicant overdose. A 17-year-old male presented after an unknown overdose. He rapidly became hypotensive and bradycardic and received aggressive supportive care without improvement. He was transferred to our institution and suffered a cardiac arrest shortly after arrival. Six minutes of advanced cardiac life support resulted in return of spontaneous circulation. High-dose insulin, lipid emulsion, and ECMO were initiated. While awaiting ECMO deployment, he again became pulseless. Compressions resumed, and after 30 min, ROSC was achieved, and he was cannulated for veno-arterial ECMO. Within 48 h, he was decannulated, and then weaned off epinephrine 2 days later. Upon extubation, he was neurologically intact. Amlodipine and metoprolol were later confirmed in serum. Adolescent poisoned patients represent an ideal population for ECMO due to lack of comorbidities. As experience with ECMO in overdose increases, additional research is needed to determine appropriate indications and timing for its use. ECMO is an option for patients poisoned with a cardiotoxicant drug, even following witnessed cardiac arrest.

Severe neurotoxicity following ingestion of tetraethyl lead.

Organic lead compounds are potent neurotoxins which can result in death even from small exposures. Traditionally, these compounds are found in fuel stabilizers, anti-knock agents, and leaded gasoline. Cases of acute organic lead intoxication have not been reported for several decades. We report a case of a 13-year-old Iraqi male who unintentionally ingested a fuel stabilizer containing 80-90% tetraethyl lead, managed at our combat support hospital. The patient developed severe neurologic symptoms including agitation, hallucinations, weakness, and tremor. These symptoms were refractory to escalating doses of benzodiazepines and ultimately required endotracheal intubation and a propofol infusion. Adjunctive therapies included chelation, baclofen, and nutrition provided through a gastrostomy tube. The patient slowly recovered and was discharged in a wheelchair 20 days after ingestion, still requiring tube feeding. Follow-up at 62 days post-ingestion revealed near-resolution of symptoms with residual slurred speech and slight limp. This case highlights the profound neurotoxic manifestations of acute organic lead compounds.

Use of amifostine, a novel cytoprotective, in alpha-amanitin poisoning.

BACKGROUND: Mortality from ingestions of the mushroom Amanita phalloides remains as high as 20-40% with many surviving patients requiring liver transplantation. A variety of treatments for Amanita ingestion have been evaluated, yet other than supportive measures, no effective therapy has been identified. In addition, an antidote for Amanita toxicity may not be practical due to delayed patient presentation. The drug amifostine was proposed to potentially improve survival from alpha-amanitin toxicity by conferring cytoprotective effects on hepatocytes at risk for cell death. Amifostine is used as a radio--and chemo-protective agent. It protects against lipoperoxidation, interferes with the cross-linking of DNA, and may act by other mechanisms yet to be identified, making it attractive for potentially attenuating ongoing hepatic necrosis. It has not previously been studied in a toxicologic model. STUDY OBJECTIVE: To determine whether amifostine is an effective postexposure therapy for alpha-amanitin, the primary lethal toxin in Amanita phalloides. METHODS: Swiss mice (n = 30 in all groups) were given an approximate LD75 dose of intraperitoneal (i.p.) alpha-amanitin. Amifostine was administered i.p. 6 h after poisoning in three cumulative dosing groups: 250 mg/kg; 500 mg/kg; and 1600 mg/kg. Controls received equal volumes of i.p. sterile 0.9% saline. Mice were monitored and time of death recorded. At day 7, survival was assumed and the remaining mice were euthanized. Qualitative histologic comparisons of hepatic and renal toxicity were performed. RESULTS: At day 7, only 10% of the control mice survived. Survival in the amifostine 250, 500, and 1600 mg/kg groups was 20%, 20%, and 3%, respectively. No statistically significant differences were detected in Kaplan-Meier survival between the control group and those receiving 250 or 500 mg/kg; however, there was a statistically significant decrease in survival for the group receiving 1600 mg/kg (p = 0.0002). CONCLUSION: No survival benefit was seen with cumulative doses between 250 and 500 mg/kg; however, higher doses may result in subsequent toxicity and decreased survival.