Impact of lowering confirmatory test cutoff value in pre-enlistment urine cannabinoids screening: about five years' experience in the French Gendarmerie.

The guidelines for screening of urinary cannabinoids require that all specimens testing positive should be confirmed by gas chromatography-mass spectrometry at a confirmatory test cutoff value of 15 ng/mL of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH). To assess the impact of lowering the confirmatory test cutoff value on the diagnostic sensitivity and efficiency of a cannabinoid testing program, the results of 986 confirmation analyses of positive screening tests, conducted in the framework of medical fitness examinations prior to enlistment in the French Gendarmerie between January 1, 2005, and December 31, 2009, were retrospectively studied. If the confirmatory test cutoff value of THCCOOH is set at 5 ng/mL instead of 15 ng/mL as recommended by guidelines, the number of confirmed results increases by 25.2%. The positive predictive value of the initial screening test rises from 63.9 to 80.0%. Only one true-positive applicant has appealed. His THCCOOH urinary concentration, which was incompatible with passive cannabis smoke exposure, was confirmed by another laboratory. The use of a confirmatory test cutoff value lower than that recommended significantly increases the diagnostic sensitivity of the screening program for urinary cannabinoids without altering its specificity.

Fatal poisoning by vanadium.

We report here a fatal intoxication case involving ammonium vanadate. A 24-year-old woman was admitted to the Emergency Department for abdominal pain, nausea, vomiting, multiple daily diarrheas, hypoglycaemia (0.2g/L) and severe acute renal failure with glomerular filtration rate estimated at 21 ml/min. This patient had taken an undetermined amount of ammonium vanadate 12h after ingesting. She died next morning in the context of respiratory distress despite intensive care and oxygen therapy. The autopsy revealed widespread asphyxia syndrome and erosive gastritis. Determination of vanadium concentration in blood was carried out by means of mass spectrometer (ICP-MS) using rhodium ((103)Rh) as the internal standard. The vanadium concentration was 6.22 mg/L, corresponding to 6000 times higher than normal concentration in the general population. The latency and the brutality of clinical picture degradation seem to be in consideration of systemic poisoning by vanadium leading to inhibition of the cellular respiratory process.

[Sexual abuse and chemical submission, a present-day problem]. / Agressions sexuelles et soumissions chimiques, un problème d'actualité.

CHEMICAL SUBMISSION: Certain forms of sexual abuse have recourse to molecules in order to obtain the victim's submission. These fast-acting, muscle-relaxing and sedative molecules, provoke anterograde amnesia that makes subsequent legal enquiries difficult. These products can be combined with alcohol or other addictive substances, therefore facilitating their administration, without the victim knowing, and enhancing their effects. THE MOLECULES USED: Among these molecules, hydroxybutyrate and its derivatives as well as benzodiazepines, with flunitrazepam, are frequently mentioned and detected. However, many other sedative molecules can be used to obtain chemical submission. MANAGEMENT OF THE VICTIMS: Knowledge of the facts and concomitant symptoms facilitates the medical and medico-legal management of the victims, generally encountered in hospital emergency wards. The quality and quantity of toxicological samples permit the use of efficient and validated techniques in organizing medico-legal enquiries.