Suspected adverse events, 2015.

The following article has been produced by the pharmacovigilance unit at the Veterinary Medicines Directorate (VMD) to provide a summary of some of the results from its surveillance work carried out in 2015Decrease in number of reports for food-producing speciesIncrease in number of pet animal reportsReports of dogs affected by medicines intended for large animals.

Summary of suspected adverse events, 2014.

The following article has been produced by the pharmacovigilance unit at the Veterinary Medicines Directorate (VMD) to provide a summary of some of the results from its surveillance work carried out in 2014.

Measurement of the flux of lead from bone to blood in a nonhuman primate (Macaca fascicularis) by sequential administration of stable lead isotopes.

To better understand the kinetics of the transfer of lead from bone to blood, we have developed and tested a method in which sequential doses of lead, each enriched with a different stable isotope, were administered in a nonhuman primate Macaca fascicularis whose skeleton had been previously labeled with lead of known isotopic composition. Lead isotopic ratios of blood and bone samples, analyzed by thermal ionization mass spectrometry (TIMS), were unmixed by isotope dilution techniques. The first label administered allows the contribution from historical bone stores to be measured. Subsequent labels allow measurement of both the historical bone stores and the previous labels that have become recently incorporated into bone. The method may be extended to studies of bone lead mobilization in pregnancy, lactation, menopause, or in disease states such as postmenopausal osteoporosis.

Imipenem prophylaxis in elective colorectal surgery.

In a randomized controlled study of 411 patients undergoing elective colorectal surgery, the efficacy and safety of two different regimens of imipenem were compared with those of a control regimen of cefuroxime plus metronidazole. Surgical infections occurred in 92 (26.4 per cent) of 349 evaluable patients. There were no major differences between the three treatment groups. It is concluded that imipenem is as effective as cefuroxime plus metronidazole in the prevention of sepsis after elective colorectal procedures.

Local recurrence after anterior resection for rectal cancer using a double stapling technique.

Fifty-five patients of mean age 69 (range 41-96) years with rectal cancer (Dukes' A:B:C, 11:24:20) underwent anterior resection using a double stapling technique under the care of one consultant surgeon between 1983 and 1988. The mean distance of the anastomosis from the anal margin was 7.2 (range 4-13) cm. The clinical leak rate was 9 per cent (five patients). There were three postoperative deaths from pulmonary embolism, lower limb ischaemia and renal failure. On prospective follow-up, 35 patients had no evidence of local or systemic cancer a median of 32 (range 24-84) months after operation; seven have died from unrelated diseases and ten from metastatic cancer. Pelvic recurrence, in four patients at 9, 11, 12 and 50 months, has occurred only in association with widespread metastasis. These results suggest that the theoretical risks of an increase in the local recurrence rate of rectal cancer after resection using a double stapling technique are not substantiated.

Sampling of cortical and trabecular bone for lead analysis: method development in a study of lead mobilization during pregnancy.

The paper describes a methodological approach to the investigation of maternal-fetal transfer of lead in a non-human primate species, with particular focus on skeletal tissue, which is known to be a site of lead deposition. Eight female cynomolgus monkeys were dosed with lead acetate during gestation, and in four of the animals, the isotopic composition of the lead was modified by enriching the amount of the stable isotope 204Pb included in the dose. Biopsy and dissection procedures for the preparation of bone samples for lead analysis and stable lead isotope analysis are described. Emphasis is placed on the containment of potential contamination of the samples by lead during preparation. Containment procedures included: use of a Class 100 clean room, special cleaning regimes and use of Teflon containers and stainless steel instruments. Preliminary data of lead concentrations in adult bone (trabecular and cortical) and fetal bone subsequent to the dosing regimen of lead during pregnancy, suggest notable differences between the two bone "compartments" examined. The bone samples of fetuses from the dams which had received enriched 204Pb showed drastically reduced 206Pb/204Pb isotope ratios.