Late-onset refractory hemolytic anemia in siblings treated for methionine synthase reductase deficiency: A rare complication possibly prevented by hydroxocobalamin dose escalation?

Methionine synthase reductase deficiency (cblE) is a rare autosomal recessive inborn error of cobalamin metabolism caused by pathogenic variants in the methionine synthase reductase gene (MTRR). Patients usually exhibit early-onset bone marrow failure with pancytopenia including megaloblastic anemia. The latter can remain isolated or patients may present developmental delay and rarely macular dysfunction. Treatment mostly includes parenteral hydroxocobalamin to maximize the residual enzyme function and betaine to increase methionine concentrations and decrease homocysteine accumulation. We report herein 2 cblE siblings diagnosed in the neonatal period with isolated pancytopenia who, despite treatment, exhibited in adulthood hemolytic anemia (LDH >11 000 U/L, undetectable haptoglobin, elevated unconjugated bilirubin) which could finally be successfully treated by hydroxocobalamin dose escalation. There was no obvious trigger apart from a parvovirus B19 infection in one of the patients. This is the first report of such complications in adulthood. The use of LDH for disease monitoring could possibly be an additional useful biomarker to adjust hydroxocobalamin dosage. Bone marrow infection with parvovirus B19 can complicate this genetic disease with erythroblastopenia even in the absence of an immunocompromised status, as in other congenital hemolytic anemias. The observation of novel hemolytic features in this rare disease should raise awareness about specific complications in remethylation disorders and plea for hydroxocobalamin dose escalation.

Association between road traffic accidents and drugs belonging to the antiseizure medications class: A pharmacovigilance analysis in VigiBase.

AIMS: Due to their central mechanism of action, antiseizure medications (ASMs) could lead to adverse effects likely to impair driving skills. Their extended use to neuropsychiatric disorders makes it a class of drugs to monitor for their road traffic accidental (RTA) potential. We aimed to assess the reporting association between ASMs and RTAs using the World Health Organization pharmacovigilance database (VigiBase). METHODS: We performed a disproportionality analysis to compute adjusted reporting odds ratios to evaluate the strength of reporting association between ASMs and RTAs. A univariate analysis using the reporting odds-ratio was used to assess drug-drug interactions between ASMs and RTAs. RESULTS: There were 1 341 509 reports associated with at least 1 ASM in VigiBase of whom 2.91‰ were RTAs reports. Eight ASMs were associated with higher reporting of RTAs compared to others (ranging from 1.35 [95% confidence interval 1.11-1.64] for lamotrigine to 4.36 [95% confidence interval 3.56-5.32] for cannabis). Eight significant drug-drug interactions were found between ASMs and the onset of RTA, mainly involving CYP450 induction. CONCLUSION: A significant safety signal between RTAs and some ASMs was identified. Association of several ASMs might further increase the occurrence of RTA. ASMs prescription in patients with identified risk factors of RTA should be considered with caution. Study number: ClinicalTrials.gov, NCT04480996.

Hazardous Drug Diversion of Valproate from a General Practitioner to his Patient's Dog.

General practitioners are key stakeholders in good prescribing practices. More than half of patients have at least one unintended medication discrepancy upon hospital admission, some of which have the potential to cause severe discomfort or clinical deterioration. We report a case of a drug mistakenly administered to a 66-year-old man with cirrhosis and chronic alcoholism. Based on his regular prescription, he received 1 g/day of valproate during a hospitalization for cardiac valve surgery. This anticonvulsant was initially prescribed by his general practitioner for his epileptic dog and has been added to his own prescription to be covered by the French national health insurance. The aim of this article is to emphasize that general practitioners, physicians, and pharmacists have a major role to play in preventing the diversion of prescription drugs and limiting the risk of adverse drug events.

Emerging drugs of abuse: current perspectives on substituted cathinones.

Substituted cathinones are synthetic analogs of cathinone that can be considered as derivatives of phenethylamines with a beta-keto group on the side chain. They appeared in the recreational drug market in the mid-2000s and now represent a large class of new popular drugs of abuse. Initially considered as legal highs, their legal status is variable by country and is rapidly changing, with government institutions encouraging their control. Some cathinones (such as diethylpropion or pyrovalerone) have been used in a medical setting and bupropion is actually indicated for smoking cessation. Substituted cathinones are widely available from internet websites, retail shops, and street dealers. They can be sold under chemical, evocative or generic names, making their identification difficult. Fortunately, analytical methods have been developed in recent years to solve this problem. Available as powders, substituted cathinones are self-administered by snorting, oral injestion, or intravenous injection. They act as central nervous system stimulants by causing the release of catecholamines (dopamine, noradrenaline, and serotonin) and blocking their reuptake in the central and peripheral nervous system. They may also decrease dopamine and serotonin transporter function as nonselective substrates or potent blockers and may inhibit monoamine oxidase effects. Nevertheless, considerable differences have been found in the potencies of the different substituted cathinones in vitro. Desired effects reported by users include increased energy, empathy, and improved libido. Cardiovascular (tachycardia, hypertension) and psychiatric/neurological signs/symptoms (agitation, seizures, paranoia, and hallucinations) are the most common adverse effects reported. Severe toxicity signs compatible with excessive serotonin activity, such as hyperthermia, metabolic acidosis, and prolonged rhabdomyolysis, have also been observed. Reinforcing potential observed in animals predicts a high potential for addiction and abuse in users. In case of overdose, no specific antidote exists and no curative treatment has been approved by health authorities. Therefore, management of acute toxic effects is mainly extrapolated from experience with cocaine/amphetamines.

Metallic profile of whole blood and plasma in a series of 106 healthy volunteers.

In 2003, we simultaneously quantified 27 metals by inductively coupled plasma-mass spectrometry (ICP-MS) in the whole blood, plasma and urine of 100 healthy volunteers. We again determined the metallic profile in whole blood and plasma during 2012. ICP-MS validated multielementary method was performed for metals in whole blood and plasma. Whole blood vanadium and chromium were quantified using ICP-MS collision cell technology. The aims of the study were to compare and assess any changes in this profile, particularly due to the environment. Healthy male/female staff volunteers (n = 106) with no professional exposure to metals, or medication containing lithium, strontium; or food supplements with trace elements and vitamins and with no metal prosthesis were included. Tobacco consumption and the number of dental amalgams were recorded. Our results demonstrated a blood lead level that had drastically decreased, i.e. reduced by half, during this period (12.5 versus 26.3 µg/L, P < 0.0001). Known differences were observed between males and females for copper and zinc; cadmium and lead were higher in smokers. Median plasmatic mercury, a specific test for dental amalgam exposure, did not significantly increase (0.38 versus 0.28 µg/L, P = 0.11). The ICP-MS metallic profile is a very practical concept that is useful for clinical, forensic and environmental toxicology, including industrial hygiene monitoring.