Endovenous laser ablation of great saphenous vein and perforator veins improves venous stasis ulcer healing.

BACKGROUND: We sought to compare the outcomes of endovenous laser ablation (EVLA) of the great saphenous vein (GSV) to EVLA of the GSV and calf incompetent perforator veins (IPVs) in management of venous stasis ulcers (VSUs). METHODS: A retrospective review of patients with active VSUs (clinical, etiology, anatomy, and pathophysiology [CEAP] classification C6) that received EVLA of the GSV or combined EVLA of the GSV and IPV between May 2005 and May 2010 was completed. Primary outcomes measured include ulcer healing and a change in the venous clinical severity score (VCSS). Secondary end points included complications, ulcer recurrence rate, and time to ulcer healing. RESULTS: Ninety-five patients (108 limbs) met inclusion criteria with active VSU (CEAP classification C6) before ablation. The average age was 58 years, with a male predominance (61%). Seventy-eight patients (91 limbs) were treated with EVLA of the GSV alone. Subgroup analysis revealed that 46 of 91 limbs (35 patients) had GSV reflux only (group 1) and 45 of 91 limbs (43 patients) had underlying IPV (group 2). Seventeen patients (17 limbs) underwent combined EVLA of the GSV and IPV (group 3). VSU healing (CEAP classification C5) occurred in 21 of 46 limbs (46%) in group 1, 15 of 45 limbs (33%) in group 2, and 12 of 17 limbs (71%) in group 3. A comparison of ulcer healing between groups 1 and 2 and between groups 1 and 3 revealed no significant difference (Fisher's exact test; P = 0.285 and P = 0.095, respectively). However, there was a significant difference in ulcer healing between groups 2 and 3 (P = 0.011). Group 1 ulcers healed in an average of 14.8 weeks, group 2 ulcers in 11.2 weeks, and group 3 in 13.2 weeks (analysis of variance; P = 0.918). Postoperative complications occurred in 7 limbs (15%) in group 1, 5 limbs (11%) in group 2, and 3 (18%) limbs in group 3. Recurrence of VSU occurred in 2 limbs (4%) in group 1, 5 limbs in group 2 (11%), and in no limbs in group 3 (Fisher's exact test; P = 0.676). Mean follow-up was 16.9 weeks for group 1, 19.2 weeks for group 2, and 14.0 weeks for group 3 (P = 0.69). CONCLUSIONS: Ulcer healing was accomplished to a significantly greater degree using EVLA of the GSV and IPV compared to GSV ablation alone for the treatment of active VSU in patients with combined reflux. This study suggests that limbs with VSU disease should be routinely examined for both superficial axial and perforator venous reflux and, when appropriate, combined ablation of the GSV and IPV should be considered in management of this disease.

CD4+CD25+ T cells protect against experimentally induced asthma and alter pulmonary dendritic cell phenotype and function.

The role of natural CD4+CD25+ regulatory T (T reg) cells in the control of allergic asthma remains poorly understood. We explore the impact of T reg cell depletion on the allergic response in mice susceptible (A/J) or comparatively resistant (C3H) to the development of allergen-induced airway hyperresponsiveness (AHR). In C3H mice, anti-CD25-mediated T reg cell depletion before house dust mite treatment increased several features of the allergic diathesis (AHR, eosinophilia, and IgE), which was concomitant with elevated T helper type 2 (Th2) cytokine production. In similarly T reg cell-depleted A/J mice, we observed a moderate increase in airway eosinophilia but no effects on AHR, IgE levels, or Th2 cytokine synthesis. As our experiments suggested that T reg cell depletion in C3H mice before sensitization was sufficient to enhance the allergic phenotype, we characterized dendritic cells (DCs) in T reg cell-depleted C3H mice. T reg cell-depleted mice had increased numbers of pulmonary myeloid DCs with elevated expression of major histocompatibility complex class II, CD80, and CD86. Moreover, DCs from T reg cell-depleted mice demonstrated an increased capacity to stimulate T cell proliferation and Th2 cytokine production, which was concomitant with reduced IL-12 expression. These data suggest that resistance to allergen-driven AHR is mediated in part by CD4+CD25+ T reg cell suppression of DC activation and that the absence of this regulatory pathway contributes to susceptibility.

Subintimal angioplasty of chronic total occlusion in iliac arteries: a safe and durable option.

BACKGROUND: Traditionally, aortobifemoral bypass has been the intervention of choice for iliac artery chronic total occlusions (CTOs). However, it is associated with significant morbidity and mortality, limiting its use in high-risk patients. To reduce procedural risk, subintimal angioplasty (SIA) for femoropopliteal CTO has been utilized by many, but few have extended this endovascular technique to treating iliac artery CTOs. We present our experience with 101 successful SIAs for iliac artery CTOs. METHODS: A retrospective review of consecutive patients with iliac artery CTOs treated with subintimal angioplasty from June 2000 to January 2009 was completed. Demographic and risk factor data were obtained, along with procedural data. Primary and secondary patency, survival, freedom from claudication, and limb salvage rates were determined by Kaplan-Meier survival analysis. Univariate and multivariate analyses were completed to identify factors adversely affecting primary patency. RESULTS: One hundred twenty patients underwent an attempted SIA of an iliac artery CTO, and 101 iliac artery CTOs were successfully treated, giving a technical success rate of 84%. Technical failure was due to the inability to re-enter the lumen in all cases. Indications for intervention were lifestyle-altering claudication in 64 patients (63%) and critical limb ischemia (CLI), in 37 (37%). Eighty-five patients underwent percutaneous SIA, while 11 patients underwent a combined SIA with surgical outflow procedure. Lesions were classified as TransAtlantic InterSociety Consensus (TASC) B, 39 (39%); TASC C, 27 (27%); and TASC D, 35 (35%). In 82 (81%) lesions, stents were deployed with an average of 1.2 (range, 0-3) stents utilized. A re-entry device was used in 14 (14%) lesions. Major complication rate was 3.0%, with a 30-day mortality rate of 1.0%. Primary and secondary patency rates at 1, 2, and 3 years were 86% and 94%, 76% and 92%, and 68% and 80%, respectively. Survival rate was 67% at 5 years, reflecting the poor health of this cohort. Limb salvage for CLI patients at 1 and 5 years was 97% and 95%, respectively. Freedom from claudication at 1 and 3 years was 89% and 73%. Univariate analysis identified hyperlipidemia, coronary artery disease, and prior surgical bypass in treated limb as factors for loss of primary patency; however, on multivariate analysis, no factors remained statistically significant. CONCLUSION: This study demonstrates that SIA of iliac CTOs is feasible and can be performed safely and effectively, even in high-risk patients. Excellent patency and limb salvage rates can be achieved. In our experience, the safety and durability of SIA makes it an attractive first-line therapy for iliac artery occlusive disease.

Beak condition drives abundance and grooming-mediated competitive asymmetry in a poultry ectoparasite community.

OBJECTIVE: Ornithonyssus sylviarum (northern fowl mite) and Menacanthus stramineus (chicken body louse) are key poultry pests currently controlled by exclusion or pesticide application. We studied how host beak condition affected their populations over time and how the lice and mites might interact on a host. METHODS: Beak-trimmed or beak-intact white leghorn hens were infested initially with either mites or lice and subsequently challenged using the alternate ectoparasite species (reciprocal transfer), while other hens harboured only the initial ectoparasite species. RESULTS: Beak-trimmed hens had far higher ectoparasite numbers relative to beak-intact hens, and the 2 ectoparasites showed evidence of grooming-mediated competitive asymmetry. On beak-trimmed hens, larger numbers of lice quickly nearly completely excluded mites in competition for enemy-free space (lower abdomen), while in the reciprocal transfer mites did not affect louse numbers on beak-trimmed hosts. The 2 ectoparasites co-existed on beak-intact hens, which were better able to defend the lower abdomen habitat by grooming. CONCLUSION: Lice are somewhat less damaging and much easier to control relative to mites, and might be used to eliminate mites in commercial, beak-trimmed flocks. Beak trimming impairs host grooming and contributes greatly to the high ectoparasite populations seen in commercial flocks. The study adds incentives for poultry breeders to develop more docile hen strains that can be held without beak trimming. This has advantages both to welfare advocates and producers who may no longer need to use insecticides for pest control or be concerned about worker exposure to pesticides.

Temperature and humidity effects on off-host survival of the Northern fowl mite (Acari: Macronyssidae) and the chicken body louse (Phthiraptera: Menoponidae).

Off-host survival of the northern fowl mite, Ornithonyssus sylviarum (Canestrini & Fanzago) (Acari: Macronyssidae), and the chicken body louse, Menacanthus stramineus (Nitzsch) (Phthiraptera: Menoponidae), was studied at 12 combinations of temperature (15, 21, 27, and 33 degrees C) and humidity (31, 65, and 85% RH). Mite protonymphs and louse third instars survived longer on average than the respective adult stages. Higher temperatures significantly reduced survival of adult and immature stages of both ectoparasites, whereas relative humidity had significant effects on O. sylviarum (especially protonymphs) but not M. stramineus. The LT50 values for adult northern fowl mites ranged from 1.9 (at 33 degrees C, 31%RH) to 8.3 d (at 15 degrees C, 85%RH), LT50 values for mite protonymphs ranged from 2.0 (at 33 degrees C, 31%RH) to 18.1 d (at 15 degrees C, 85%RH), LT50 values for adult lice ranged from 0.5 (at 33 degrees C, 31%RH) to 1.7 d (at 15 degrees C, 65%RH), and LT50 values for nymphal lice ranged from 1.2 (at 33 degrees C, 65%RH) to 3.3 d (at 21 degrees C, 31%RH). Maximum survival of the northern fowl mite was up to 35 d for adults and 29 d for protonymphs. Maximum survival for the chicken body louse was 3.3 d for adults and 5.8 d for nymphs. The data provide minimum guidelines for leaving poultry houses vacant long enough to allow ectoparasites to die before introduction of subsequent new flocks.