Zulfikarali Verjee

Chronic Cocaine Exposure in a Toddler Revealed by Hair Test

Since then, hair assay has been widely used to detect intrauterine exposure to different substances, as well as exposure in adults. Although the length of hair available limits the detection window, this test can provide critical information during longer periods of time than a blood or urine test. We describe a case in which a hair test allowed diagnosis of chronic cocaine exposure in a toddler that was missed by an initial urine toxicology screen after an acute presentation.

Ontogeny of renal P-glycoprotein expression in mice: correlation with digoxin renal clearance.

Digoxin is eliminated mainly by the kidney through glomerular filtration and P-glycoprotein (P-gp) mediated tubular secretion. Toddlers and young children require higher doses of digoxin per kilogram of bodyweight than adults, although the reasons for this have not been elucidated. We hypothesized there is an age-dependant increase in P-gp expression in young children. The objectives of this study were to elucidate age-dependant expression of renal P-gp and its correlation with changes in the clearance rate of digoxin. FVB mice were killed at different ages to prepare total RNA for P-gp expression studies. Semi-quantitative RT-PCR was conducted to analyze mdr1a and mdr1b ontogeny in the kidney at: birth, 7, 14, 21, 28 and 45-d old adults. The pharmacokinetics of digoxin (7 μg/kg) was studied in mice of the same age groups. Newborn and Day 7 levels of both mdr1a and mdr1b were marginal. Day 21 mdr1b levels were significantly higher than both Day 14 and Day 28 levels. Digoxin clearance rates were the highest at Day 21, with significant correlation between P-gp expression and clearance values. Increases in digoxin clearance rates after weaning may be attributed, at least in part, to similar increases in P-gp expression.

Contamination of Hair With 3,4-Methylene Dioxymethamphetamine (Ecstasy) in 2 Young Girls from a “Meth Lab”

In mid-2006, police raided a family house in the province of Ontario, Canada, and found evidence suggesting that it had been used to manufacture MDMA or methamphetamine, together with the chemicals butane and buthylamine, and packages containing MDMA, cocaine, and heroin. The family living in the house included 2 girls, each aged 14 months and 8 years, and their parents. We performed a pediatric examination after the girls were transferred to the care of CAS. They appeared in good health and were apparently well cared for. The older girl was a bright student, according to the report provided by her teacher. The younger girl was usually with her mother. Both girls regularly visited the doctor, and their vaccination status was up to date. Physical examination revealed no major health problems or concerns. Their development was normal for their age, and both showed excellent interaction with their mother, the pediatrician, and the social worker. As part of the consultation, a hair sample for drug testing was obtained from each girl, with written consent from the mother and the CAS representative in charge. Hair from both children was positive for either MDMA or methamphetamine (enzyme-linked immunosorbent assay cross-reactivity approaches 100% for these 2 drugs) at relatively high levels (8.63 and 1.35 ng/mg of hair, respectively; range The recent explosion in the number of “meth home labs” illegally producing methamphetamine has brought to the forefront the serious public health issues associated with this illegal practice. It is not uncommon to find children residing in these households, and their environmental exposure to illicit drugs produced in the premises has not been systematically evaluated. Two years ago, because of the increase in numbers of meth home labs detected by police, the Motherisk Program at the Hospital for Sick Children initiated, in collaboration with the Children’s Aid Society (CAS), a program to follow all children found to reside in homes where methamphetamine laboratories operated. A key question that arose is whether there is a risk of environmental exposure to amphetamines in this setting. We describe the use of hair test to detect 3,4-methylene dioxymethamphetamine (MDMA or ecstasy) exposure in 2 girls residing in a household where a meth lab operated.

Monitoring lithium in breast milk: An individualized approach for breastfeeding mothers

Clinical Pharmacology & Therapeutics (2003) 73, P9–P9; doi:

Pediatric reference intervals for lymphocyte vitamin C (ascorbic acid)

OBJECTIVE To establish pediatric reference intervals for lymphocyte vitamin C. DESIGN AND METHODS This was a prospective study of 194 well children aged 0-7 years old of mixed ethnicity who had blood drawn for the purpose of this study. Blood was collected during elective surgery under general anesthesia and lymphocytes isolated and stored as frozen ascorbic acid lymphocyte lysates for later HPLC analysis by previously described methodology. Reference intervals were established according to the Clinical and Laboratory Standards Institute (CLSI) and the International Federation of Clinical Chemistry (IFCC) guidelines (C28-A3). Horn-Pesce robust method was used to estimate the 95% confidence interval and 95% reference interval. RESULTS Reference intervals were independent of age or gender and shown to be 12.9-52.8 μg/10(8) cells (lymphocytes). CONCLUSION We have defined pediatric reference ranges for lymphocyte vitamin C in healthy, fasted children at a relevant age group (0-7 years). The new reference interval can now be used to more reliably explore possible implications of variation of vitamin C levels on bleeding and other clinical signs.

PIII-45IV busulfan: Pharmacokinetics in children undergoing hematopoietic stem cell transplant

Conditioning regimens preceding stem cell transplant (SCT) often include oral busulfan, and may be complicated by hepatic veno‐occlusive disease (HVOD). IV busulfan (IV Bu) causes less HVOD in adults. We describe the pharmacokinetics (PK) of IV Bu in infants and children, determine its incidence and correlate IV Bu AUC with its development.

Carbamazepine (CBZ) Interference with Tricyclic Antidepressant (TCAD) Assays

Clinical Pharmacology & Therapeutics (1996) 59, 214–214; doi: 10.1038/sj.clpt.1996.357