Patients with drug-eluting stents and management of their anticoagulant therapy in cutaneous surgery

Whether a patient has a drug-eluting stent (DES) implanted may not seem to be an immediate concern for a dermatologist. However, the clinician needs to consider a patient's risk of bleeding if a patient is to undergo a cutaneous surgical procedure. Patients with skin cancer are generally older with a higher risk of comorbidities such as cardiovascular disease with history of cardiac stent implantation. After DES placement, patients are typically on long-term dual antiplatelet therapy, which increases the risk of bleeding. However, stopping antiplatelet therapy prematurely can lead to serious thrombotic complications. Thus, when performing a dermatologic procedure in a patient with a DES, the physician must weigh the risks of bleeding complications with continuing antiplatelet therapy against the risk of thrombotic complications associated with stopping antiplatelet therapy. The aim of this review is to identify the issues for the dermatologist and the dermatologic surgeon surrounding the perioperative treatment of patients with a DES and to discuss the treatment of patients with an implanted DES.     

Thrombozytenaggregationshemmer und Antikoagulanzien

Many patients requiring dermatologic surgery are taking anticoagulants or antiplatelet agents. The perioperative management of these drugs is not standardized and affected by fear of bleeding complications. Studies show only moderate increase in bleeding complications while taking these drugs. Our clinical experience shows no significant peri- or postoperative bleeding. As part of a risk assessment, thromboembolic complications outweigh any bleeding risk of surgery. Therefore, in the experience of the authors, blood thinning drugs should be continued before and during dermatosurgical procedures. General assessment of laboratory parameters concerning coagulation or platelet function is not necessary and can be restricted to selected subgroups of patients.     

Heparin-induced thrombocytopenia in solid organ transplant recipients: The current scientific knowledge

Exposure to heparin is associated with a high incidence of immunization against platelet factor 4 (PF4)/heparin complexes. A subgroup of immunized patients is at risk of developing heparin-induced thrombocytopenia (HIT), an immune mediated prothrombotic adverse drug effect. Transplant recipients are frequently exposed to heparin either due to the underlying end-stage disease, which leads to listing and transplantation or during the transplant procedure and the perioperative period. To review the current scientific knowledge on anti-heparin/PF4 antibodies and HIT in transplant recipients a systematic PubMed literature search on articles in English language was performed. The definition of HIT is inconsistent amongst the publications. Overall, six studies and 15 case reports have been published on HIT before or after heart, liver, kidney, and lung transplantation, respectively. The frequency of seroconversion for anti-PF4/heparin antibodies ranged between 1.9% and 57.9%. However, different methods to detect anti-PF4/heparin antibodies were applied. In none of the studies HIT-associated thromboembolic events or fatalities were observed. More importantly, in patients with a history of HIT, reexposure to heparin during transplantation was not associated with thrombotic complications. Taken together, the overall incidence of HIT after solid organ transplantation seems to be very low. However, according to the current knowledge, cardiac transplant recipients may have the highest risk to develop HIT. Different alternative suggestions for heparin-free anticoagulation have been reported for recipients with suspected HIT albeit no official recommendations on management have been published for this special collective so far.     

Effect of ureteric stents on urological infection and graft function following renal transplantation

AIM: To compare urological infections in patients with or without stents following transplantation and to determine the effect of such infections on graft function.METHODS: All 285 recipients of kidney transplantation at our centre between 2006 and 2010 were included in the study. Detailed information including stent use and transplant function was collected prospectively and analysed retrospectively. The diagnosis of urinary tract infection was made on the basis of compatible symptoms supported by urinalysis and/or microbiological culture. Graft function, estimated glomerular filtration rate and creatinine at 6 mo and 12 mo, immediate graft function and infection rates were compared between those with a stent or without a stent.RESULTS: Overall, 196 (183 during initial procedure, 13 at reoperation) patients were stented following transplantation. The overall urine leak rate was 4.3% (12/277) with no difference between those with or without stents - 7/183 vs 5/102, P = 0.746. Overall, 54% (99/183) of stented patients developed a urological infection compared to 38.1% (32/84) of those without stents (P = 0.0151). All 18 major urological infections occurred in those with stents. The use of stent (Wald χ² = 5.505, P = 0.019) and diabetes mellitus (Wald χ² = 5.197, P = 0.023) were found to have significant influence on urological infection rates on multivariate analysis. There were no deaths or graft losses due to infection. Stenting was associated with poorer transplant function at 12 mo.CONCLUSION: Stents increase the risks of urological infections and have a detrimental effect on early to medium term renal transplant function.     

Treatment of transplant renal artery pseudoaneurysm using expandable hydrogel coils: A case report and review of literature

Transplant renal artery (TRA) pseudoaneurysm can result in bleeding, infection, graft dysfunction and graft loss. We report the management of a renal transplant recipient who presented five months after renal transplantation with deterioration of renal function, who was found to have TRA pseudoaneurysm and TRA stenosis. Both were treated radiologically by using expandable hydrogel coils (EHC) in combination with stenting. Improvement in clinical, biochemical and radiological parameters were observed after the intervention. To our knowledge, this is the first report in the transplant literature on the use of EHC for the treatment of a TRA pseudoaneurysm.     

Post-transplant erythrocytosis after kidney transplantation: A review

Post-transplant erythrocytosis (PTE) is defined as persistently elevated hemoglobin > 17 g/dL or hematocrit levels > 51% following kidney transplantation, independent of duration. It is a relatively common complication within 8 months to 24 months post-transplantation, occurring in 8%-15% of kidney transplant recipients. Established PTE risk factors include male gender, normal hemoglobin/hematocrit pre-transplant (suggestive of robust native kidney erythropoietin production), renal artery stenosis, patients with a well-functioning graft, and dialysis before transplantation. Many factors play a role in the development of PTE, however, underlying endogenous erythropoietin secretion pre-and post-transplant is significant. Other contributory factors include the renin-angiotensin- aldosterone system, insulin-like growth factors, endogenous androgens, and local renal hypoxia. Most patients with PTE experience mild symptoms like malaise, headache, fatigue, and dizziness. While prior investigations showed an increased risk of thromboembolic events, more recent evidence tells a different story-that PTE perhaps has lessened risk of thromboembolic events or negative graft outcomes than previously thought. In the evaluation of PTE, it is important to exclude other causes of erythrocytosis including malignancy before treatment. Angiotensin converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARBs) are the mainstays of treatment. Increased ACE-I/ARB use has likely contributed to the falling incidence of erythrocytosis. In this review article, we summarize the current literature in the field of post-transplant erythrocytosis after kidney transplantation.     

Chances and risks of sodium-glucose cotransporter 2 inhibitors in solid organ transplantation: A review of literatures

Solid organ transplantation offers life-saving treatment for patients with end-organ dysfunction. Patient survival and quality of life have improved over the past few decades as a result of pharmacological development, expansion of the donor pool, technological advances and standardization of practices related to transplantation. Still, transplantation is associated with cardiovascular complications, of which post-transplant diabetes mellitus (PTDM) is one of the most important. PTDM increases mortality, which is best documented in patients who have received kidney and heart transplants. PTDM results from traditional risk factors seen in patients with type 2 diabetes mellitus, but also from specific post-transplant risk factors such as metabolic side effects of immunosuppressive drugs, post-transplant viral infections and hypomagnesemia. Oral hypoglycaemic agents are the first choice for the treatment of type 2 diabetes mellitus in non-transplanted patients. However, the evidence on the safety and efficacy of oral hypoglycaemic agents in transplant recipients is limited. The favourable risk/benefit ratio, which is suggested by large-scale and long-term studies on new glucose-lowering drug classes such as glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter 2 inhibitors, makes studies warranted to assess the potential role of these agents in the management of PTDM.     

A correlation found between contact allergy to stent material and restenosis of the coronary arteries

Background:  Metallic implants, stents, are increasingly being used especially in patients with stenosis of the cardiac vessels. Ten to thirty per cent of the patients suffer from restenosis regardless of aetiology. We have shown increased frequency of contact allergy to stent metals in stented patients.
Objectives:  To we evaluate whether contact allergy to stent material is a risk factor for restenosis.
Methods:  Patients with stainless steel stents, with or without gold plating, were epicutaneously tested and answered a questionnaire. The restenosis rate was evaluated.
Results:  We found a correlation between contact allergy to gold, gold stent, and restenosis (OR 2.3, CI 1.0–5.1, P  = 0.04). The risk for restenosis was threefold increased when the patient was gold allergic and stented with a gold-plated stent. An increased degree of chest pain in gold-allergic patients stented with gold-plated stent was found.
Conclusions:  We found a correlation between contact allergy to gold, gold-stent, and restenosis. It may be of importance to consider contact allergy when developing new materials for stenting.     

Donor to recipient sizing in thoracic organ transplantation

Donor-to-recipient organ size matching is a critical aspect of thoracic transplantation. In the United States potential recipients for lung transplant and heart transplant are listed with limitations on donor height and weight ranges, respectively. Height is used as a surrogate for lung size and weight is used as a surrogate for heart size. While these measures are important predictors of organ size, they are crude surrogates that fail to incorporate the influence of sex on organ size. Independent of other measures, a man’s thoracic organs are approximately 20% larger than a woman’s. Lung size can be better estimated using the predicted total lung capacity, which is derived from regression equations correcting for height, sex and age. Similarly, heart size can be better estimated using the predicted heart mass, which adjusts for sex, age, height, and weight. These refined organ sizing measures perform better than current sizing practice for the prediction of outcomes after transplantation, and largely explain the outcome differences observed after sex-mismatch transplantation. An undersized allograft is associated with worse outcomes. In this review we examine current data pertaining to size-matching in thoracic transplantation. We advocate for a change in the thoracic allocation mechanism from a height-or-weight-based strategy to a size-matching process that utilizes refined estimates of organ size. We believe that a size-matching approach based on refined estimates of organ size would optimize outcomes in thoracic transplantation without restricting or precluding patients from thoracic transplantation.     

Anesthesia for bronchoscopic amniotic membrane grafting to treat non-healing bronchial dehiscence

Airway complications after lung transplantation remain a significant cause of morbidity and mortality. Many of these occur at the anastomotic sites, which are susceptible due to poor collateral circulation. Of the possible complications, bronchial dehiscence is particularly formidable. These cases have been successfully treated bronchoscopically with metallic stents, which likely promote healing through granulation tissue formation. However, limited options exist in cases where the dehiscence fails to heal following stent placement. Here, we present the case report of a 65-year-old male who developed bronchial dehiscence status post bilateral lung transplantation for idiopathic pulmonary fibrosis that failed to heal with simple stent placement. Eventually, the patient underwent amniotic membrane grafting with stenting as a novel therapy for non-healing bronchial dehiscence, for which we describe the anesthetic management. His anesthetic plan included inhalational induction with sevoflurane, propofol infusion for total intravenous anesthesia, rocuronium for muscle relaxation, and closed-circuit assisted ventilation. His existing tracheostomy was used as the airway for oxygenation and induction. In summary, our anesthetic plan for the lung transplant patient was effective; future amniotic membrane grafting for bronchial dehiscence through bronchoscopy may follow a similar technique. Ultimately, the choice of anesthesia in this patient population requires judicious consideration of the requirements of the procedure as well as the pathophysiology of the transplanted lung.     

Anticoagulación y antiagregación en Dermatología

An increasing number of patients who are receiving anticoagulation or antiplatelet therapy require cutaneous surgery. Such pharmacotherapies are usually suspended based on experience in gynecologic, thoracic, and abdominal surgery. However, this practice may increase the risk of suffering a thromboembolic event. We review perioperative management of anticoagulant and antiplatelet therapy, complications associated with suspending therapy, and side effects.     

Successful endovascular treatment of transplant intrarenal artery stenosis in renal transplant recipients: Two case reports

Transplant renal artery stenosis(TRAS) is a relatively rare complication after renal transplantation. The site of the surgical anastomosis is most commonly involved, but sites both proximal and distal to the anastomosis may occur, as well. Angioplasty is the gold standard for the treatment of the stenosis, especially for intrarenal lesions. We report two cases of intrarenal TRAS and successful management with angioplasty without stent placement. Both patients were male, 44 and 55 years old respectively, and they presented with elevated blood pressure or serum creatinine within three months after transplantation. Subsequently, they have undergone angioplasty balloon dilatation with normalization of blood pressure and serum creatinine returning to baseline level. Percutaneous transluminal balloon renal angioplasty is a safe and effective method for the treatment of the intrarenal TRAS.     

Hydrophilic polymer vasculopathy with coinciding pseudoxanthoma elasticum‐like changes in an amputated toe

For the past decades, hydrophilic polymer gel coating have been widely used on endovascular devices to decrease friction and to aid with binding and delivering of medications in drug‐eluting stents. In the recent years, hydrophilic polymer emboli disease has been recognized as an iatrogenic adverse effect which has led to considerable morbidity and mortality of patients. This under‐recognized embolic phenomenon now has reproducible pathognomonic histologic findings. Small‐ to medium‐sized blood vessels are occluded with basophilic, amorphous, non‐refractile, non‐polarizable and whirled aggregates of foreign body material. Depending on the affected organ, the patients have variable symptomatology, from livedo racemosa, gangrene of extremities to cardiac arrhythmias, hemiparesis, stroke and death. Here, we present a unique case of hydrophilic polymer vasculopathy 6 years post‐endovascular procedure with coinciding pseudoxanthoma elasticum‐like changes. As the literature has seen increased reporting of individual cases and case series documenting the patients’ diverse symptomatology; hydrophilic polymer vasculopathy should be entertained sooner in the patient's differential diagnosis.     

Skin lesions in adult liver transplant recipients: a study of 100 consecutive patients

BACKGROUND: The surgical advances made in the area of organ transplantation along with the use of more efficacious immunosuppression have meant an increase in patient survival. This longer-living transplant population has started to exhibit cutaneous problems, some of which lead to an increased mortality while others lead to a decline in the quality of life. OBJECTIVES: The primary objective was to determine the different types of cutaneous lesions encountered in the adult liver transplant population. Secondary objectives were to determine the impact, if any, of the duration of transplant, the type of immunosuppression involved and the degree of sun exposure and skin phototype, on the skin cancers encountered in this transplanted population. METHODS: Two dermatologists examined 100 consecutive liver transplant recipients (LTRs) attending the transplant outpatient department. Skin examination included the face and whole body and lesions found were categorized into the following groups: cutaneous malignancies, squamoproliferative lesions, cutaneous infections and others that did not fall into any of these categories. RESULTS: The reasons for organ transplantation were numerous. The mean age at transplantation was 42.5 years. The average time since transplantation was 5.5 (range 0.75-16 years). Four patients developed skin cancers; among them there were a total of seven skin cancers (one squamous cell carcinoma, six basal cell carcinomas). Fungal infections accounted for 19% of all cutaneous infections seen, viral infections 2% and bacterial infections 5%. Triple-drug immunosuppressive therapy (ciclosporin A, azathioprine and prednisolone) was used in 35% of LTR patients, while dual therapy (tacrolimus and prednisolone) was used in 48% and monotherapy (tacrolimus) was used in 17% of LTRs. CONCLUSIONS: Immunosuppressive therapy is believed to be one of the most important risk factors in the development of skin cancer in solid organ transplant recipients. The relatively low prevalence of skin cancer in our liver transplant population may in part be explained by the relatively high percentage of recipients on dual and monotherapy (48% and 17% respectively), and the shorter duration of therapy. Our study suggests that although LTRs are at higher risk of developing nonmelanoma skin cancer than the general population, the risk is comparable with other solid organ transplant recipients.     

STEMI多支血管病变患者采用血流储备分数指导下进行支架植入的远期疗效

目的探讨ST段抬高型心肌梗死(STEMI)多支血管病变患者采用血流储备分数(FER)指导下进行支架植入的远期疗效。方法选择2014年2月-2015年2月内蒙古医科大学第一附属医院心血管内科行经皮冠状动脉介入治疗(PCI)开通梗死相关血管(IRA),拟分期PCI治疗非IRA(non-IRA)的86例STEMI多支血管病变患者作为研究对象,按随机数字表法将其分为冠状动脉造影(CAG)指导下支架植入组(CAG组,n=43)与FFR指导下支架植入组(FFR组,n=43),FFR组对狭窄>90%的non-IRA病变及FFR<0.80且直径≥2.5 mm的non-IRA病变行PCI治疗,对狭窄70%-90%的non-IRA病变行FFR检查,对FFR≥0.80的non-IRA病变给予药物治疗;CAG组对狭窄270%且直径22.5 mm的non-IRA病变行PCI治疗。比较两组临床基线资料、冠状动脉病变程度、PCI治疗资料,随访两组患者术后36个月主要不良心脑血管事件(MACCE)的发生情况。结果两组PCI成功率、平均支架直径、住院费用、PCI时间、围术期主要并发症、住院时间P>0.05;FFR组患者平均支架置入数、人均支架总长度、狭窄≥70%病变支架置入率、造影剂用量明显低于CAG组,P<0.0);随访期间FFR组MACCE发生率(23.26%)显著低于CAG组(44.19%),P<0.05。结论STEMI多支血管病变患者采用FFR指导下进行支架植入可减少造影剂用量和支架置入数量,降低术后36个月MACCE发生率。     

Bleeding complications in dermatologic surgery

Although the overall incidence is low, bleeding complications in dermatologic surgery can occur and be the source of significant patient morbidity. In this article, we summarize the key aspects of preoperative assessment of patients at risk for bleeding. A review of current issues and literature regarding safe continuation of anticoagulant and antiplatelet medications in dermatologic surgery patients is also presented. In addition, principles for management of bleeding events, should they occur, are also highlighted.     

Bleeding complications in dermatologic surgery

Although the overall incidence is low, bleeding complications in dermatologic surgery can occur and be the source of significant patient morbidity. In this article, we summarize the key aspects of preoperative assessment of patients at risk for bleeding. A review of current issues and literature regarding safe continuation of anticoagulant and antiplatelet medications in dermatologic surgery patients is also presented. In addition, principles for management of bleeding events, should they occur, are also highlighted.     

Post-transplantation lymphoproliferative disorders: Current concepts and future therapeutic approaches

Transplant recipients are vulnerable to a higher risk of malignancy after solid organ transplantation and allogeneic hematopoietic stem-cell transplant. Post-transplant lymphoproliferative disorders (PTLD) include a wide spectrum of diseases ranging from benign proliferation of lymphoid tissues to frank malignancy with aggressive behavior. Two main risk factors of PTLD are: Firstly, the cumulative immunosuppressive burden, and secondly, the oncogenic impact of the Epstein-Barr virus. The latter is a key pathognomonic driver of PTLD evolution. Over the last two decades, a considerable progress has been made in diagnosis and therapy of PTLD. The treatment of PTLD includes reduction of immunosuppression, rituximab therapy, either isolated or in combination with other chemotherapeutic agents, adoptive therapy, surgical intervention, antiviral therapy and radiotherapy. In this review we shall discuss the prevalence, clinical clues, prophylactic measures as well as the current and future therapeutic strategies of this devastating disorder.     

New onset hypertension after transplantation

It has been reported that up to 90% of organ transplant recipients have suboptimal blood pressure control. Uncontrolled hypertension is a well-known culprit of cardiovascular and overall morbidity and mortality. In addition, rigorous control of hypertension after organ transplantation is a crucial factor in prolonging graft survival. Nevertheless, hypertension after organ transplantation encompasses a broader range of causes than those identified in non-organ transplant patients. Hence, specific management awareness of those factors is mandated. An in-depth understanding of hypertension after organ transplantation remains a debatable issue that necessitates further clarification. This article provides a comprehensive review of the prevalence, risk factors, etiology, complications, prevention, and management of hypertension after organ transplantation.     

Leprosy in a renal transplant recipient: a case report and literature review

Leprosy is rarely seen in organ transplant patients; only ten cases of leprosy in organ transplant recipients have been reported. We herein report a Taiwanese renal transplant recipient concomitantly infected with borderline lepromatous leprosy. A 68-year-old male received renal transplantation at Guilin, China, in 2000, and then received immunosuppressive therapy with prednisolone, tacrolimus, and mycophenolate. Three years after transplantation, multiple erythematous tender nodules and plaques over the face and lower limbs developed. Biopsies and histopathological examination confirmed the diagnosis of leprosy. We treated the patient with a multidrug regimen including dapsone, clofazimine, and rifampine since November of 2003 with a good response. Unfortunately, he suffered from a cluster of complications after an accidental fall, finally leading to septic shock and death five months later. In summary, we report a rare case of new-onset leprosy after renal transplantation in Taiwan and suggest leprosy should be listed in the differential diagnosis of unusual skin manifestations in organ transplant patients.