Oral warfarin intake affects skin inflammatory cytokine responses in rats

Toxicology of chemical biocides: Anticoagulant rodenticides - Beyond hemostasis disturbance

The use of anticoagulant rodenticides (ARs) is one of the most commonly employed management methods for pest rodents. ARs compete with vitamin K (VK) required for the synthesis of blood clotting factors in the liver, resulting in inhibition of blood coagulation and often animal death due to hemorrhage. Besides rodents (target species), ARs may affect non-target animal species and humans. Out of hemostasis disturbance, the effects of ARs may be related to the inhibition of proteins that require VK for their synthesis but are not involved in the coagulation process, to their direct cytotoxicity, and their pro-oxidant/proinflammatory activity. A survey of the cellular and molecular mechanisms of these sublethal/asymptomatic AR effects is given in this review. Data from field, clinical, and experimental studies are presented. Knowledge of these mechanisms might improve hazard characterization and identification of potential ecotoxicological risks associated with ARs, contributing to a safer use of these chemicals.

Surgical Site Infections in Elderly Fragility Hip Fractures Patients Undergoing Warfarin Treatment

OBJECTIVES

Surgical site infection (SSI) is a devastating complication of proximal femoral fracture surgery, related with an increased morbidity and mortality. As warfarin treatment has been described as a risk factor for SSI, we aimed to compare patient and SSI characteristics in warfarin and nonanticoagulated patients.

DESIGN

Retrospective cohort study.

SETTING

Level-1 trauma center.

PATIENTS

Individuals 65 years of age and older with fragility hip fractures.

INTERVENTION

Patients were divided into 2 cohorts: warfarin treated (n = 85) or nonanticoagulated (n = 771). Demographics, in-hospital characteristics, laboratory data, prior hospitalizations, recent antibiotic use, and 1-year incidence of SSIs and their characteristics were gathered.

MAIN OUTCOME MEASURES

Postoperative SSIs.

RESULTS

Twelve patients (14.1%) from the warfarin group and 21 patients (2.7%) from the noncoagulated group had SSI (P < 0.001). Both groups were comparable in terms of demographics and Charlson comorbidity score. Warfarin-treated patients had reduced white blood and neutrophils counts (10.1 ± 3.2 vs. 11.6 ± 4.0 cells/mm and 8.1 ± 3.2 vs. 9.6 ± 3.9 cells/mm for both comparisons respectively; P < 0.001 for both). They were more likely to be admitted to a geriatric ward than to orthopedics ward and were delayed to theater (58.5 ± 44.5 vs. 30.6 ± 27.4 hours; P < 0.001). Following surgery, there was no difference in blood transfusions required, in-hospital complications, or time to infection. Rates of prior hospitalizations, antibiotic use, or type of bacteria did not differ.

CONCLUSIONS

Warfarin treatment in fragility hip fracture surgery is correlated with an increased risk for SSI, regardless of in-hospital complications, and hospitalizations before surgery or to the infection itself.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Widespread anticoagulant poison exposure in predators in a rapidly growing South African city

Anticoagulant rodenticides (ARs) are used worldwide to control rodent populations. ARs bioaccumulate across trophic levels and threaten non-target wildlife. We investigated the prevalence of AR exposure in seven predator species in the rapidly developing Greater Cape Town region of South Africa - a mosaic of natural, urban, and agricultural areas within a global biodiversity hotspot. We focused sampling on caracals (Caracal caracal, n = 28) as part of a larger caracal ecology study, but also opportunistically sampled Cape Clawless otters (Aonyx capensis, n = 9), large-spotted genets (Genetta tigrina, n = 4), honey badger (Mellivora capensis, n = 1), water mongoose (Atilax paludinosus, n = 1), small gray mongoose (Galerella pulverulenta, n = 1), and Cape Eagle owl (Bubo capensis, n = 1). We tested livers from all species, and blood from ten caracals, for eight AR compounds to assess prevalence and amount of exposure for each compound. We used generalized linear models to test spatial, demographic, and seasonal risk factors for ten measures of AR exposure in caracals. We detected at least one of the four most toxic AR compounds in six species. Exposure was high for caracals (92%) and all species combined (81%). For caracals, proximity to vineyards was the most important AR exposure risk factor. Vineyards in Cape Town do not use ARs to protect their vines but do host commercial hospitality structures where ARs are used. Vineyards may thus link caracals that forage within vineyards to the rat poisons used in and around their commercial structures. Residue levels were unexpected in large-spotted genets and Cape Clawless otters, suggesting invertebrate vectors. ARs may present a cryptic threat to populations already vulnerable to increasing habitat loss, vehicle collisions, poachers and fire. Targeted mitigation should include a mix of environmentally responsible policies that reduce AR use, particularly in areas near wildlife habitat.