Soluble vascular endothelial growth factor receptor-1 as a novel marker of arteriovenous fistula stenosis in hemodialysis patients.

INTRODUCTION: Arteriovenous fistula (AVF) stenosis is one of the most important clinical problems in hemodialysis patients. The histopathological findings of neointimal hyperplasia and impaired angiogenesis have been well established in stenotic AVFs. Soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) has been implicated in pathological angiogenesis. Thus, we aimed to investigate the association between sVEGFR-1 and AVF stenosis in hemodialysis patients. METHODS: This prospective cohort study included 70 patients with end-stage renal disease. Forty-five patients were included in the final analysis, and the median follow-up period was 36 months. Venous stenosis was detected by physical examination and documented by fistulography. Blood samples were analyzed a day before the fistula operation, and serum levels of sVEGFR-1 were measured. FINDINGS: The median sVEGFR-1 level was higher in the stenosis group than in the nonstenosis group (17 pg/mL [89.5%] vs. 5 pg/mL [19.2%], respectively; P < 0.001]. According to body mass index (BMI) categories, obese patients (BMI > 30 kg/m2 ) had the shortest stenosis-free survival (20 months [9.35-30.65]). Multivariate Cox analysis showed that sVEGFR-1, serum creatinine, and parathyroid hormone levels were associated with AVF stenosis risk. Kaplan-Meier survival curves showed that patients with less than the median value of sVEGFR-1 (<6093.07 pg/mL) had longer cumulative stenosis-free survival than patients with sVEGFR-1 levels above the median value (P < 0.001). DISCUSSION: Increased levels of sVEGFR-1 and obesity were found to be associated with AVF stenosis in hemodialysis patients.

Hypoxia-inducible factors in arteriovenous fistula maturation: A prospective cohort study.

BACKGROUND: Neointimal hyperplasia is the main cause of arteriovenous fistula (AVF) failure. Hypoxia-inducible factors (HIFs) factors are associated with neointimal hyperplasia. Thus, we investigated the association between HIF-2 alpha (HIF-2α) and AVF maturation in end-stage kidney disease (ESKD) patients. METHODS: This prospective cohort study was conducted in 21 voluntary healthy subjects and 50 patients with ESKD who were eligible for AVF creation. Inclusion criteria were being ESKD patients without a history of AVF surgery and dialysis. Eight patients excluded from the study due to having unavailable veins six patients were excluded due to acute thrombosis after surgery. One patient lost to follow-up. A total of 35 patients were included in final analysis. The blood samples were collected a day before the AVF surgery for biochemical parameters and HIF-2α measurement. HIF-2α levels were measured by the ELISA method. RESULTS: Compared with healthy subjects, ESKD patients had a significantly higher level of HIF-2α. [1.3 (1.0-1.9) vs 2.2 (1.6-3.0)] (P = .002). Patients were divided into two groups after the evaluation of AVF maturation, as the mature group (n = 19) and the failure group (n = 16). Serum HIF-2α level was 1.7 (1.1-1.8) in the mature group; however, it was 3.1 (2.8-3.3 in failure group (P < .001). Multiple logistic regression analyses showed that HIF-2α independently predicted AVF maturation. The ROC curve analysis showed that HIF-2α > 2.65 predicted AVF maturation failure with the 87% sensitivity and 94% specificity [AUC:0.947, 95% CI (0.815-0.994), P < .001]. CONCLUSIONS: HIF-2-α levels were higher in ESKD patients than healthy subjects. HIF-2-α could be a marker of AVF maturation failure.

Cutaneous ulcerations caused by Paecilomyces variotii in a renal transplant recipient.

Skin infections caused by Paecilomyces species have been rarely described in patients with solid organ transplantation. Cutaneous manifestations are highly variable and include erythematous macules, nodules, pustules, and vesicular and necrotic lesions. The diagnosis of these infections is generally made by examination of a skin biopsy. Management of these fungal infections is difficult due to the immunocompromised state of the patients. Moreover, antifungal therapy and immunosuppressive drug interactions should be considered during treatment management. Herein, we reported a case of cellulitis caused by Paecilomyces variotii in a 56-year-old man who had undergone a kidney transplantation. Erythematous macular and nodular lesions on the left hand and left foot appeared first; within 2 months the skin lesions became ulcerated, hemorrhagic, and progressively painful and the patient was admitted to our hospital. The diagnosis was made by skin biopsy and tissue culture. The skin lesions resolved by the sixth week of the treatment with voriconazole.