Leg Ulcers in Sickle Cell Disease

Controversies in the pathophysiology of leg ulcers in sickle cell disease

Patients with sickle cell disease (SCD) often experience painful vaso-occlusive crises and chronic haemolytic anaemia, as well as various acute and chronic complications, such as leg ulcers. Leg ulcers are characterized by their unpredictability, debilitating pain and prolonged healing process. The pathophysiology of SCD leg ulcers is not well defined. Known risk factors include male gender, poor social conditions, malnutrition and a lack of compression therapy when oedema occurs. Leg ulcers typically start with spontaneous pain, followed by induration, hyperpigmentation, blister formation and destruction of the epidermis. SCD is characterized by chronic haemolysis, increased oxidative stress and decreased nitric oxide bioavailability, which promote ischaemia and inflammation and consequently impair vascular function in the skin. This cutaneous vasculopathy, coupled with venostasis around the ankle, creates an ideal environment for local vaso-occlusive crises, which can result in the development of leg ulcers that resemble arterial ulcers. Following the development of the ulcer, healing is hindered as a result of factors commonly observed in venous ulceration, including venous insufficiency, oedema and impaired angiogenesis. All of these factors are modulated by genetic factors. However, our current understanding of these genetic factors remains limited and does not yet enable us to accurately predict ulceration susceptibility.

Approach to the Atypical Wound

The heterogeneity of atypical wounds can present diagnostic and therapeutic challenges; however, as the prevalence of atypical wounds grows worldwide, prompt and accurate management is increasingly an essential skill for dermatologists. Addressing the underlying cause of an atypical wound is critical for successful outcomes. An integrated approach with a focus on pain management and patient engagement is recommended to facilitate enduring wound closure. Advances in treatment, in addition to further research and clinical training, are necessary to address the expanding burden of atypical wounds.

Factors Associated with Leg Ulcers in Adults with Sickle Cell Disease in Brazil

OBJECTIVE

To define the prevalence of leg ulcers and identify the clinical and laboratory factors associated with leg ulcers in adult participants.

METHODS

The authors conducted a cross-sectional study of 1,109 patients who were 18 years or older with SS or Sβ0-thalassemia genotypes from a Brazilian cohort. Investigators assessed the prevalence of factors associated with leg ulcers from 2013 to 2017.

RESULTS

The prevalence of leg ulcers was 21%. Increasing age (odds ratio [OR], 1.07; range, 1.06-1.09), male sex (OR, 2.03; range, 1.44-2.87), treatment with chronic transfusion therapy (OR, 1.88; range, 1.15-3.03), higher indirect bilirubin levels (OR, 1.48; range, 1.02-2.16), and low hemoglobin levels (OR, 2.17; range, 1.52-3.11) were associated with leg ulcers. Participants who self-reported as Black (OR, 6.75; range, 2.63-21.32), mixed (OR, 3.91; range, 1.55-12.20), and other/unknown (OR, 3.84; range, 1.04-15.24) were more likely to have leg ulcers compared with those who self-reported as White.

CONCLUSIONS

The prevalence of leg ulcers in this Brazilian cohort was higher than the prevalence reported in developed countries. Known factors such as age and male sex were corroborated. The increased bilirubin level and decreased hemoglobin levels among participants with leg ulcers support the hypothesis that hemolysis is correlated with leg ulcer pathogenesis. Self-reported black skin color was an independent predictor of leg ulcers and warrants further study to understand the etiology and implications of this finding.

Cutaneous manifestations of sickle cell disease: an updated review

Sickle cell disease is a common and highly morbid genetic condition that is characterized by multi-system involvement, including numerous cutaneous manifestations. Persistent and recurrent leg ulceration has long been considered the dermatological hallmark of those with sickle cell disease, but there have been recent descriptions of associated infection with rare pathogens and episodes of liverdoid vasculopathy. Growing considerations for this population in the literature include cutaneous reactions to common treatments such as hydroxyurea and clinical management of the intersection between sickle cell disease and conditions like plaque psoriasis. Recent studies have also demonstrated an increased resistance to skin carcinogenesis for those with sickle cell disease through unclear mechanisms. However, though the body of knowledge regarding cutaneous manifestations and considerations of sickle cell disease is slowly expanding, it does not match the considerable disease and symptom burden faced by these patients. More research is needed to better delineate our understanding of these cutaneous manifestations of sickle cell disease to improve outcomes and further management.

Treatment dilemmas: strategies for priapism, chronic leg ulcer disease, and pulmonary hypertension in sickle cell disease

Sickle cell disease is a disorder characterized by chronic hemolytic anemia and multiorgan disease complications. Although vaso-occlusive episodes, acute chest syndrome, and neurovascular disease frequently result in complication and have well-documented guidelines for management, the management of chronic hemolytic and vascular-related complications, such as priapism, leg ulcers, and pulmonary hypertension, is not as well recognized despite their increasing reported prevalence and association with morbidity and mortality. This chapter therefore reviews the current updates on diagnosis and management of priapism, leg ulcers, and pulmonary hypertension.

Cost effectiveness of a specialist wound care service

The Burden of Wounds Study estimated the cost of wound care across the UK to be £5.3 billion, with £3 billion associated with hard-to-heal wounds. This article looks at potential cost savings of managing hard-to-heal leg ulcers in a specialist wound care service using a multidisciplinary team (MDT) approach. This unique approach includes: a consultant dermatologist; a podiatrist specialising in mobility and gait; a clinical psychologist; clinical nurse specialists; and allied health professionals from tissue viability and lymphoedema services. Bringing together specialists from supporting disciplines provides a one-stop service for the patient. We conducted a retrospective analysis (over 365 days) of wound healing in patients attending the service for management of leg ulcers with differing aetiologies, including venous and atypical leg ulceration. Many of the patients referred to the service had a long wound history, between two and nine years, with a duration up to 25 years in the most complex cases. Within this complex cohort of patients, higher levels of focused compression was required (Accelerate Strapping, Accelerate, UK) for retromalleolar ulceration and management of foot oedema needing toe bandaging or garments. Wound healing was achieved in 72% of patients across all wound aetiologies, demonstrating the impact that a specialist MDT team can have on positive healing outcomes, and which can result in cost savings to the health economy and an improved quality of life for the patient.

Common, But Neglected: A Comprehensive Review of Leg Ulcers in Sickle Cell Disease

OBJECTIVE

To compile available evidence to better understand the management of leg ulcers in sickle cell disease (SCD), as well as describe potential therapeutic steps that may be required to improve the quality of life of patients with SCD leg ulcers.

DATA SOURCES

MEDLINE, PubMed, EMBASE, and Web of Science databases.

STUDY SELECTION

A comprehensive search was conducted to retrieve relevant studies using the keywords "sickle cell disease and leg ulcer," "ulcer treatments, diagnosis and sickle cell," and "wound sickle cell." Studies published through July 2020 were included.

DATA EXTRACTION

Two independent authors selected all studies that assessed the relationship between leg ulcer and SCD identified from online databases.

DATA SYNTHESIS

The authors have summarized updated information on pathophysiology (vasculopathy linked to chronic hemolysis and endothelial dysfunction), diagnosis, and available treatment options to unravel the dermohematologic connection between leg ulcers and SCD.

CONCLUSIONS

It is the authors' hope that this detailed discussion of the information available on leg ulcers and SCD will lead to a better appreciation of this clinical problem by the clinicians and researchers and in turn have a long-term positive effect on the quality of life of patients with SCD. Researchers should design new trials considering these insights and potential therapeutic approaches based on current knowledge.

Interventions for treating leg ulcers in people with sickle cell disease

BACKGROUND

The frequency of skin ulceration makes an important contributor to the morbidity burden in people with sickle cell disease. Many treatment options are available to the healthcare professional, although it is uncertain which treatments have been assessed for effectiveness in people with sickle cell disease. This is an update of a previously published Cochrane Review.

OBJECTIVES

To assess the clinical effectiveness and harms of interventions for treating leg ulcers in people with sickle cell disease.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register. We searched LILACS (1982 to January 2020), ISI Web of Knowledge (1985 to January 2020), and the Clinical Trials Search Portal of the World Health Organization (January 2020). We checked the reference lists of all the trials identified. We also contacted those groups or individuals who may have completed relevant randomised trials in this area. Date of the last search of the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register: 13 January 2020; date of the last search of the Cochrane Wounds Group Trials Register: 17 February 2017.

SELECTION CRITERIA

Randomised controlled trials of interventions for treating leg ulcers in people with sickle cell disease compared to placebo or an alternative treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion. All three authors independently assessed the risk of bias of the included studies and extracted data. We used GRADE to assess the quality of the evidence.

MAIN RESULTS

Six studies met the inclusion criteria (198 participants with 250 ulcers). Each trial investigated a different intervention and within this review we have grouped these as systemic pharmaceutical interventions (L-cartinine, arginine butyrate, isoxsuprine) and topical pharmaceutical interventions (Solcoseryl® cream, arginine-glycine-aspartic acid (RGD) peptide dressing and topical antibiotics). No trials on non-pharmaceutical interventions were included in the review. All trials had an overall unclear or high risk of bias, and drug companies sponsored four of them. We were unable to pool findings due to the heterogeneity in outcome definitions, and inconsistency between the units of randomisation and analysis. Three interventions reported on the change in ulcer size (arginine butyrate, RGD peptide, L-cartinine). Of these, only arginine butyrate showed a reduction of ulcer size compared with a control group, mean reduction -5.10 cm² (95% CI -9.65 to -0.55), but we are uncertain whether this reduces ulcer size compared to standard care alone as the certainty of the evidence has been assessed as very low. Three trials reported on complete leg ulcer closure (isoxsuprine, arginine butyrate, RGD peptide matrix; very low quality of evidence). None reported a clinical benefit. No trial reported on: the time to complete ulcer healing; ulcer-free survival following treatment for sickle cell leg ulcers; quality of life measures; incidence of amputation or harms.

AUTHORS' CONCLUSIONS

Given the very low quality of the evidence identified in this updated Cochrane Review we are uncertain whether any of the assessed pharmaceutical interventions reduce ulcer size or result in leg ulcer closure in treated participants compared to controls. However, this intervention was assessed as having a high risk of bias due to inadequacies in the single trial report. Other included studies were also assessed as having an unclear or high risk of bias. The harm profile of the all interventions remains inconclusive.

Treatment of recalcitrant chronic leg ulcer in a known sickle cell anaemia patient using honey and fresh hbaa red cell concentrate in a Nigerian secondary healthcare facility

Sickle hemoglobin (HbS) formed by the point mutation in the genetic code of beta-globin chain leading to valine substituting glutamic acid at position 6 of the beta-chain. The resultant sickle cell disease (SCD) characterized by occlusion of microvasculature by red blood cells is associated with multiple organ pathologies. One of such complications is chronic leg ulcers. We report a case of chronic leg ulcer, in a known sickle cell anemia patient, which did not respond to the wound dressing methods at the hospital's disposal. The ulcer was successfully treated using standard operative procedure (S.O.P) in wound care, applying local honey, and use of blood transfusion. EA was a 20-year-old university undergraduate who was admitted to April 2019 in Central Hospital Benin City with chronic leg ulcer of 1 year duration. She was also anemic with hemoglobin concentration of 3.0 g/dl (packed cell volume 15%). The wound was dressed with local honey, and anemia corrected with blood transfusion using concentrated red cells lacking the HbS trait. There was a progressive improvement in the healing of the ulcer with total closure after 4 months of treatment. Maintenance and follow-up measures were instituted to prevent reoccurrence. This report showed that honey has remarkable properties in promoting wound healing. Its usage in combination with transfusion of HbA red blood cells to manage chronic leg ulcers in SCD patients is advocated. However, this calls for further studies and research.

Prevalence and Predictive Factors for Leg Ulcers in Sickle Cell Disease Patients in Saudi Arabia: A Cross-Sectional Observational Study

Introduction

Saudi Arabia has a high prevalence of sickle cell disease (SCD). Leg ulceration is one of the complications associated with SCD. There is a gap in the literature in regard to the prevalence of leg ulcers among SCD patients in Saudi Arabia.

Objectives

The primary objective of this study was to evaluate the lifetime prevalence of leg ulcers in SCD patients in our population and to study the predictive factors of leg ulcers by using sociodemographic factors, clinical manifestations of SCD, and other relevant factors like hydroxyurea.

Methods

A cross-sectional study design was utilized. Data collection was done using an electronic survey to collect self-reported information for the prevalence of leg ulcers and possible associated factors. The survey was distributed using social media platforms. Chi-square test was used to test for the presence of an association between having leg ulcers and sociodemographic variables as well as SCD related history. Furthermore, binary logistic regression was utilized to determine factors predicting the incidence of leg ulcers among SCD.

Results

A total of 790 valid responses were included in the study. Among these, 646 were included in the analysis of leg ulcers prevalence. From them, 52 (8%) SCD patients reported a history of leg ulcers. The male to female ratio was (9.7% vs 7.2%). The age group most affected by leg ulcers was those older than 50 (16.7%). There was no significant association between a history of leg ulcers and sociodemographic variables. The only predictive factors for leg ulcers were having six to eight vaso-occlusive crises per month and having more than eight vaso-occlusive crises per month.

Conclusion

Leg ulcers among SCD patients in Saudi Arabia were considerably prevalent (8%). There was no statistically significant correlation between leg ulceration and sociodemographic variables. Leg ulcers were more likely in patients with a history of highly frequent vaso-occlusive crises. No association was found between the incidence of leg ulcers and other complications of sickle cell disease or hydroxyurea.

Leg Ulcers in Sickle-Cell Disease: Treatment Update

Significance: Sickle-cell leg ulcers (SCLUs) are a severe, chronic, and recurrent complication of sickle-cell disease (SCD). There are no official recommendations for treatment. Recent Advances: Only a few studies with a high level of evidence have been conducted to evaluate treatment of SCLUs. However, several studies have been conducted with a high level of evidence to evaluate the efficacy of treatments in venous leg ulcers, and SCLUs could benefit from these treatments, especially when a venous incompetence or an edema is associated. Pathophysiology of SCLUs includes a vasculopathy related to chronic hemolysis and an endothelial dysfunction, which could be therapeutic approaches to SCLU treatment. Critical Issues: Therapeutic approaches to SCLUs can target SCD on the one hand and skin healing and associated aggravating factors on the other. A review of the literature found only case series and six randomized controlled trials; some offered encouraging results, but most had serious biases. Clinical trials specifically targeting SCLUs are difficult to realize because of the small number of affected patients, in comparison with patients with leg ulcers from other causes. Future Direction: Treating SCLUs remains a challenge. Data in the literature are currently insufficient to offer clear treatment guidelines because of several biases in controlled studies. New studies are under way to assess the efficacy of topical treatments and describe the microbiome of SCLUs. Prevention of SCLU recurrence should be assessed in future clinical trials because the high risk of recurrence is an unsolved critical issue.

Review/overview of pain in sickle cell disease

Sickle cell disease (SCD) is a highly complex inherited disorder of hemoglobin structure. Although the molecular lesion is a single-point mutation, the sickle gene is pleiotropic in nature causing multiple phenotypic expressions that constitute the various complications of the disease. Its manifestations could be acute, chronic, nociceptive, neuropathic that could occur singly or in various combinations. Pain continues to be the major factor of SCD phenotypic complications and the most common cause of admissions to the Emergency Department and/or the hospital. Although progress has been made in understanding the pathophysiology of SCD as well as in developing curative therapies such as hematopoietic stem cell transplantation and gene therapy, effective pain management continues to lag behind. Palliative therapies continue to be the major approach to the management of SCD and its complications. The advent of hydroxyurea made partial success in preventing the frequency of vaso-occlusive crises and l-glutamine awaits post-trial confirmation of benefits. The search for additional pharmacotherapeutic agents that could be used singly or in combination with hydroxyurea and/or l-glutamine awaits their dawn hopefully in the near future. The purpose of this review is to describe the various manifestations of SCD, their pathophysiology and their current management. Recent impressive advances in understanding the pathophysiology of pain promise the determination of agents that could replace or minimize the use of opioids.

Approaches to Microthrombotic Wounds: A Review of Pathogenesis and Clinical Features

GENERAL PURPOSE

To discuss the pathogenesis and clinical features of wounds caused by microthrombi formation under the following categories of systemic diseases: cold-related and immune-complex deposition diseases, coagulopathies, abnormalities in red blood cell structure, emboli, and vasospasm.

TARGET AUDIENCE

This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

LEARNING OBJECTIVES/OUTCOMES

After participating in this educational activity, the participant should be better able to:1. Recall the etiology, risk factors, and pathophysiology of the various types of microthrombotic wounds.2. Describe the clinical manifestations and treatment of the various types of microthrombotic wounds.

ABSTRACT

Typical wounds such as diabetic foot ulcers, venous leg ulcers, pressure ulcers, and arterial ulcers are responsible for more than 70% of chronic wounds. Atypical wounds have broad differential diagnoses and can sometimes develop as a combination of different conditions. Regardless of the etiology, impaired blood circulation is characteristic of all chronic and acute wounds. Chronic wounds associated with microthrombi formation are an important group of atypical wounds commonly linked to an underlying systemic disease. In this perspective article, the pathogenesis and clinical features of wounds caused by microthrombi formation are discussed under the following categories of systemic diseases: cold-related and immune-complex deposition diseases, coagulopathies, abnormalities in red blood cell structure, emboli, and vasospasm.

Impact of Sickle Cell Anemia on Inpatient Morbidity After Spinal Fusion

STUDY DESIGN

A retrospective study.

OBJECTIVE

To determine the impact of sickle cell anemia on perioperative outcomes and resource utilization in elective spinal fusion surgery.

SUMMARY OF BACKGROUND DATA

Sickle cell anemia has been identified as an important surgical risk factor in otolaryngology, cardiothoracic surgery, general surgery, and total joint arthroplasty. However, the impact of sickle cell anemia on elective spine surgery is unknown.

METHODS

Hospitalizations for elective spinal fusion surgery between the years of 2001-2014 from the US National Inpatient Sample were identified using ICD-9-CM codes and patients were grouped into those with and without sickle cell anemia. The main outcome measures were in-hospital neurological, respiratory, cardiac, gastrointestinal, renal and urinary, pulmonary embolism, and wound-related complications and mortality. Length of stay and inpatient costs were also collected. Multivariable logistic regressions were conducted to compare the in-hospital outcomes of patients undergoing elective spinal fusion with or without sickle cell anemia.

RESULTS

From a total of 4,542,719 patients undergoing elective spinal fusions from 2001 to 2014, 456 sickle cell disease patients were identified. Sickle cell anemia is a significant independent predictor for pulmonary embolism [odds ratio (OR)=7.37; confidence interval (CI), 4.27-12.71; P<0.001], respiratory complications (OR=2.36; CI, 1.63-3.42; P<0.001), wound complications (OR=3.84; CI, 2.72-5.44; P<0.001), and overall inpatient complications (OR=2.58; CI, 2.05-3.25; P<0.001). Sickle cell anemia patients also have significantly longer length of stay (7.0 vs. 3.8 d; P<0.001) and higher inpatient costs ($20,794 vs. $17,608 P<0.05).

CONCLUSIONS

Sickle cell anemia is associated with increased risk of perioperative complications and greater health care resource utilization. Sickle cell anemia patients undergoing spinal fusion surgeries should be counseled on these increased risks. Moreover, current strategies for perioperative management of sickle cell anemia patients undergoing spinal fusion surgery need to be improved.

Mini review: leg ulcers - a secondary complication of sickle cell disease

Sickle cell disease (SCD) is a group of inherited blood disorders recognized by WHO as a major public health problem. It affects morbidity and mortality of the affected population considerably. Leg ulcer in the lower limbs is a hallmark feature of SCD. Meticulous physical examination, thorough history, laboratory tests, and imaging will lead to proper diagnosis and lead to proper treatment and management of the cases. Although newer treatment strategies have improved the prognostic outcome of SCD, leg ulcers still are a disabling and difficult to treat a complication of the condition. This mini review summarizes this common complication of SCD.

Sickle cell disease: Clinical presentation and management of a global health challenge

Sickle cell disease is an autosomal recessive, multisystem disorder, characterised by chronic haemolytic anaemia, painful episodes of vaso-occlusion, progressive organ failure and a reduced life expectancy. Sickle cell disease is the most common monogenetic disease, with millions affected worldwide. In well-resourced countries, comprehensive care programs have increased life expectancy of sickle cell disease patients, with almost all infants surviving into adulthood. Therapeutic options for sickle cell disease patients are however, still scarce. Predictors of sickle cell disease severity and a better understanding of pathophysiology and (epi)genetic modifiers are warranted and could lead to more precise management and treatment. This review provides an extensive summary of the pathophysiology and management of sickle cell disease and encompasses the characteristics, complications and current and future treatment options of the disease.

Brief topical sodium nitrite and its impact on the quality of life in patients with sickle leg ulcers

Cutaneous ulceration from sickle cell disease negatively impacts quality of life. Topical sodium nitrite has previously been shown to reduce the size of sickle leg ulcers. This study examined how topical sodium nitrite impacted the quality of life scores in patients with sickle leg ulcers.We prospectively collected data in patients enrolled in a leg ulcer study (n = 17) or an allogeneic hematopoietic cell transplant study (nonulcer group, n = 15). Both groups completed a pretreatment Short Form-36 questionnaire; the ulcer group completed a second questionnaire after 4 weeks of topical sodium nitrite applications. Data were analyzed by age, sex, >50% area improvement postintervention, and sickle-related complications (vaso-occlusive crises, pulmonary hypertension, or avascular necrosis). Physical and mental component summary scores were analyzed with Student t test.Physical summary scores were lower than mental summary scores in all groups, indicating leg ulcers among other sickle related complications negatively impacted physical quality of life measures. After sodium nitrite use, physical summary scores improved in the leg ulcer group (34.5 ± 9.4 to 39 ± 10.3, P = .03), and mental summary scores improved more in ulcerated patients ≤35 years old (40.7 ± 6.9 to 51.7 ± 9.7, P = .01).Brief topical sodium nitrite has the potential to improve quality of life, especially in younger individuals. Longer treatment duration and randomized-controlled trials are needed to confirm the efficacy of this topical therapy.

Use of a National Electronic Health Record Network to Describe Characteristics and Healing Patterns of Sickle Cell Ulcers

Objective: Sickle cell ulcers affect as many as 15% of patients with sickle cell disease in the United States and severely impact quality of life. An understanding of baseline healing patterns is important to inform study design for future trials that test therapies for this disease. Approach: In this study, an electronic wound management system was leveraged to analyze retrospective data on 133 unique sickle cell patients who were treated across 114 wound healing centers, and to describe their characteristics and healing patterns as compared with those of venous ulcer patients. The data included 198 care episodes for 427 wounds. Results: Patients with sickle cell ulcers were younger and had fewer comorbid diseases than those with venous ulcers. Larger size and longer duration were predictors of poor healing. Between the first and fourth assessments, mean change in area for sickle cell ulcers showed a 58% increase, compared with a 13% decrease for venous ulcers. Kaplan-Meier curves showed poorer healing in sickle cell ulcers than in venous ulcers across all categories of size and duration. Patients with sickle cell ulcers had longer care episodes and were more likely to re-present for care. Innovation: This study reports on the largest data set of sickle cell ulcer patients analyzed to date in the published literature to provide a more detailed understanding of wound healing patterns of this disease. Conclusion: A national network of electronic health records can effectively identify a large number of patients with sickle cell ulcers to support analysis of epidemiology, healing patterns, and health care utilization.

Elevated Proangiogenic Markers are Associated with Vascular Complications within Ghanaian Sickle Cell Disease Patients

: Sickle cell disease (SCD) is an inherited blood disorder that can result in vasculopathy and end organ damage. Angiogenesis has been implicated as a key contributing factor to vascular mediated tissue injury in SCD. The relative plasma levels of angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), and vascular endothelial growth factor (VEGF) greatly influence angiogenesis. Dysregulation of these growth factors, leading to a pro-angiogenic state in SCD patients, has been documented in the developed world but there is very little data in Africa. There is the need, therefore, for studies in Ghanaian SCD patients. The aim of this study was to assess plasma levels of Ang-1, Ang-2, and VEGF in homozygous (HbSS) SCD patients with or without complications and healthy controls (HbAA) in Ghana. The study was a case-control study involving 544 participants: 396 HbSS SCD patients and 148 HbAA healthy controls. The study was conducted at the Center for Clinical Genetics (Sickle Cell Clinic) and Accra Area Blood Centre for National Blood transfusion at the Korle-Bu Teaching Hospital, Accra, Ghana. The plasma levels of Ang-1, Ang-2, and VEGF of study participants were measured with a double sandwich enzyme-linked immunosorbent assay (ELISA) technique. Complete blood count (CBC) was measured with an autoanalyser. The mean plasma Ang-1, Ang-2, and VEGF were significantly higher in HbSS SCD patients with or without complications than healthy controls (p < 0.001). The Ang-2/Ang-1 ratio was significantly lower in the controls than the HbSS patients (p < 0.001). The Ang-2/Ang-1 ratio was higher in the HbSS patients with leg ulcers as compared with patients with other complications and healthy controls (p < 0.001). There were higher leucocyte counts in HbSS patients than healthy controls. Overall, there was elevated plasma levels of Ang-1, Ang-2, and VEGF in SCD patients. The higher Ang-2/Ang-1 plasma levels in patients with leg ulcers suggests a possible ongoing angiogenesis and response to inflammatory stimuli. The study provides a first report on plasma levels of angiopoietin-1, angiopoietin-2, and vascular endothelial growth factors in homozygous sickle cell disease patients in Ghana.

Treatment of 100 chronic thalassemic leg wounds by plasma-rich platelets

OBJECTIVE

Thalassemia is a heterogeneous group of congenital hemoglobinopathies caused by mutations in the globin gene complex that result in an unbalanced globin synthesis. Unmatched globin chains bind to the cytosolic surface of red blood cell membrane where they cause oxidative damage that might in part be responsible for membrane weakness. The deformability of red blood cells and hypercoagulable state in thalassemic patients have been incriminated in leg ulcer formation, as this might cause ischemia to the skin and consequently friability and ulceration.

METHODS

Platelet-rich plasma (PRP) gel is considered an advanced wound therapy for chronic and acute wounds. PRP gel consists of cytokines, growth factors, chemokines, and a fibrin scaffold derived from a patient's blood. In this study, we treated 100 thalassemic leg wounds using PRP.

RESULTS

There was wound size reduction in patients after 4 weeks of treatment. In wounds with 2-3.5 cm² surface area, complete closure happened after 12.5 weeks, 5-12 cm² wounds completely closed after 13.2 weeks, and finally, 4.5-6 cm² wounds healed completely after 14 weeks. None of the wounds reopened after 8 months of monitoring.

CONCLUSION

This study will help extrapolation of the use of PRP for at least thalassemic leg wound treatment.

Critical Reviews: How we treat sickle cell patients with leg ulcers

The past five decades have seen an improvement in the mortality and morbidity of sickle cell disease (SCD) because of prophylaxis against infectious complications, improved and expanded red cell transfusions, implementation of hydroxyurea therapy, and advances in supportive care. Now that the majority of patients in the western hemisphere reaches adulthood, end organ diseases are frequent, which include vasculopathic complications such as chronic leg ulcers. The management of patients with leg ulcers requires the hematologist to lead a team of health care professionals, and investigates the presence of associated, but potentially still occult signs of vasculopathy, such as pulmonary hypertension, renal disease, priapism and retinopathy. These complications may be asynchronous, and long term careful screening is indicated, in order to ensure early diagnosis and intervention. It is crucial to address both the immediate consequences of pain, infection and disability, and long term effects on quality of life, employment and stigma associated with chronic ulceration. Recent insights into their pathophysiology may have practical implications. We propose a holistic approach to the management of patients' physical and emotional problems and mechanisms of ulcers formation and delayed healing. An overview of topical and systemic therapies for chronic ulcers is given, with the understanding that wound care therapy is best left to the wound specialists, medical and surgical, with whom the hematologist must keep an open line of communication. In the absence of evidence-based guidelines, our opinion is based on both a critical review of the literature and our personal clinical and research experience.

A treatment algorithm to identify therapeutic approaches for leg ulcers in patients with sickle cell disease

Sickle cell leg ulcers (SCLUs) are a common complication of sickle cell disease (SCD). Patients who develop ulcers appear to have a more severe haemolysis-associated vasculopathy than individuals who do not develop them, and manifest other complications such as priapism and pulmonary hypertension. SCLUs are slow to heal and often recur, affecting both the emotional and physical well-being of patients. Here we summarise what is known about the pathophysiology of SCLUs, describe available treatment options and propose a treatment algorithm.

Hemoglobinopathies and Leg Ulcers

Major hemoglobinopathies, including sickle cell anemia, are becoming a global health issue. Leg ulcers are the most common cutaneous manifestation of sickle cell disease and an important contributor to morbidity burden in this population. Leg ulcers following sickling disorders are extremely painful, and hard to heal. The clinical evidence for the optimal management of these ulcers is limited. Treating the cause and the strategies to prevent sickling are the mainstay of treatment. The basic principles of wound bed preparation and compression therapy is beneficial in these patients.

Interventions for treating leg ulcers in people with sickle cell disease

BACKGROUND

The frequency of skin ulceration makes it an important contributor to the morbidity burden in people with sickle cell disease. Many treatment options are available to the healthcare professional, although it is uncertain which treatments have been assessed for effectiveness in people with sickle cell disease.

OBJECTIVES

To assess the clinical effectiveness and safety of interventions for treating leg ulcers in people with sickle cell disease.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register.We searched LILACS (1982 to August 2012), the African Index Medicus (up to August 2012), ISI Web of Knowledge (1985 to August 2012), and the Clinical Trials Search Portal of the World Health Organization (August 2012). We checked the reference lists of all the trials identified. We also contacted those groups or individuals who may have completed relevant randomised trials in this area.Date of the last search of the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register: 21 July 2014; date of the last search of the Cochrane Wounds Group Trials Register: 18 September 2014.

SELECTION CRITERIA

Randomised controlled trials of interventions for treating leg ulcers in people with sickle cell disease compared to placebo or an alternative treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion. All three authors independently assessed the risk of bias of the included studies and extracted data.

MAIN RESULTS

Six studies met the inclusion criteria (198 participants with 250 ulcers). Each trial investigated a different intervention and within this review we have grouped these as systemic pharmaceutical interventions (L-cartinine, arginine butyrate, isoxsuprine) and topical pharmaceutical interventions (Solcoseryl(®) cream, RGD peptide dressing, topical antibiotics). Three interventions reported on the change in ulcer size (arginine butyrate, RGD peptide, L-cartinine). Of these, RGD peptide matrix significantly reduced ulcer size compared with a control group, mean reduction 6.60cm(2) (95% CI 5.51 to 7.69; very low quality of evidence). Three trials reported on the incidence of complete closure (isoxsuprine, arginine butyrate, RGD peptide matrix; ranging between low and very low quality of evidence). None reported a significant effect. No trial reported on: the time to complete ulcer healing; ulcer-free survival following treatment for sickle cell leg ulcers; quality of life measures; or incidence of amputation. There was no reported information on the safety of these interventions.

AUTHORS' CONCLUSIONS

There is evidence that a topical intervention (RGD peptide matrix) reduced ulcer size in treated participants compared to controls. This evidence of efficacy is limited by the generally high risk of bias associated with these reports.We planned to analyse results according to general groups: pharmaceutical interventions (systemic and topical); and non-pharmaceutical interventions (surgical and non-surgical). However, we were unable to pool findings due to the heterogeneity in outcome definitions, and inconsistency between the unit of randomisation and the unit of analysis. This heterogeneity, along with a paucity of identified trials, prevented us performing any meta-analyses.This Cochrane review provides some evidence for the effectiveness of one topical intervention - RGD peptide matrix. However, this intervention was assessed as having a high risk of bias due to inadequacies in the single trial report. Other included studies were also assessed as having a high risk of bias. We recommend that readers interpret the trial results with caution. The safety profile of the all interventions was inconclusive.

Topical sodium nitrite for chronic leg ulcers in patients with sickle cell anaemia: a phase 1 dose-finding safety and tolerability trial

BACKGROUND

Well-tolerated and effective treatments are needed for chronic leg ulcers in sickle cell anaemia. Topical sodium nitrite, a known nitric oxide donor, enhances blood flow in ulcers and has known bacteriostatic effects. We aimed to assess the safety, tolerability, and pharmacokinetics of topical sodium nitrite in patients with sickle cell disease and chronic leg ulcers.

METHODS

We enrolled adult patients from an ambulatory clinic at the National Institutes of Health (Bethesda, MD, USA) with sickle cell anaemia with leg ulcers (with a surface area of 2.5-100 cm²) persisting for at least 4 weeks into a safety and tolerability phase 1 dose-escalation trial of topical sodium nitrite. Increasing concentrations of sodium nitrite cream were applied twice weekly for 4 weeks to one ulcer per patient at five dose levels (0.5%, 1%, 1.5%, 1.8%, and 2%). The primary endpoints were safety and tolerability, with secondary endpoints of pharmacokinetics, blood flow, and wound healing. Pain relief was analysed post hoc. Endpoints were analysed over time for the whole study population and according to dose level. This study is registered with ClinicalTrials.gov, number NCT01316796.

FINDINGS

Between April 4, 2011, and March 19, 2013, we enrolled 18 adult patients with sickle cell anaemia and leg ulcers into our trial. We assigned three patients into each cohort, and each cohort was treated with a different concentration of sodium nitrite cream (cohort 1: 0.5%, cohort 2: 1.0%, cohort 3: 1.5%, and cohort 4: 2.0%). Patients were not enrolled into the next cohort dose until we were able to establish that no dose-limiting toxicities were observed. An additional six patients were enrolled to cohort 3a: 1.8%, after two patients in cohort 4 had asymptomatic drops in diastolic blood pressure. No grade 3-4 adverse events were observed, and there were no serious adverse events or dose-limiting side-effects. Pharmacokinetic analysis showed that systemic absorption of sodium nitrite was very low. Application of topical sodium nitrite was associated with a significant increase in peri-wound cutaneous blood flow measured by laser speckle contrast imaging (p=0.0002), corroborated by increased peri-wound skin temperature by infrared thermography (p=0.0119). We recorded a dose-dependent decrease in leg ulcer size (p=0.0012) and pain (p<0.0001). Ulcers healed completely in three patients who received the highest concentrations of topical sodium nitrite (the 1.8% and 2% cream). In our post-hoc analysis of pain, brief pain inventory scores improved in pain severity (p=0.0048) and pain interference (p=0.0013).

INTERPRETATION

Our results indicate that topical sodium nitrite 2% cream is suitable for additional clinical trials in adults with sickle cell anaemia to promote healing of leg ulcers.

FUNDING

National Heart, Lung and Blood Institute Division of Intramural Research (National Institutes of Health).

Vasculopathy, inflammation, and blood flow in leg ulcers of patients with sickle cell anemia

Chronic leg ulcers are frequent and debilitating complications of sickle cell anemia. Inadequate blood supply has been postulated to be an important factor in their occurrence and delayed healing. Little is known about their microcirculatory and histopathological changes. We evaluated the microcirculation of lower extremity ulcers with laser speckle contrast imaging and infrared thermography and obtained clinical and laboratory characteristics in 18 adults with sickle cell anemia and chronic leg ulcers. Skin biopsies were obtained in four subjects. Subjects had markers of severe disease, anemia, high degree of hemolysis, inflammation, and thrombophilia. The highest blood flow was present in the ulcer bed, progressively less in the immediate periwound area, and an unaffected control skin area in the same extremity. Microscopic examination showed evidence of venostasis, inflammation, and vasculopathy. Blood vessels were increased in number, had activated endothelium and evidence of thrombosis/recanalization. High blood flow may be due to chronic inflammation, cutaneous vasodilatation, venostasis, and in situ thrombosis. These changes in skin microcirculation are similar to chronic venous ulcers in the non-sickle cell disease (SCD) population, thus suggesting that leg ulcers may be another end-organ complication with endothelial dysfunction that appears in patients with SCD at a younger age and with higher frequency than in the general population.

Leg ulcers in sickle cell disease: current patterns and practices

Leg ulcers are a debilitating complication of patients with sickle cell disease, and their frequency in North America was reported to be 2.5% by the Cooperative Study of Sickle Cell Disease more than 20 years ago. We sought to determine if the frequency of leg ulcers in sickle cell patients in the United States had declined and to assess which treatments providers use most commonly. We sent an e-mail survey to health professionals belonging to the national Sickle Cell Adult Provider Network. Responses were obtained from 31 of them (26.0%). Most of them (96.0%) reported having some patients with leg ulcers. Providers reported a total of 185 patients with active leg ulcers and 224 in the previous 5 years, for a total of 409 patients. Hb SS (homozygous sickle cell anemia) was the most common genotype of affected individuals, followed by Hb SC (double heterozygote for Hb S [β6(A3)Glu→Val, GAG>GTG; HBB: c.20A>T] and Hb C [β6(A3)Glu→Lys, GAG>AAG; HBB: c.19G>A]). Males showed a 2:1 predominance. Two-thirds of patients were treated with either hydroxyurea (HU) or transfusion therapy and most used compression stockings and topical therapies as directed by wound care services. We conclude that leg ulcers continue to be a debilitating complication of young adults with sickle cell disease, despite improved supportive care and the widespread use of disease modifying agents such HU and transfusion. While some providers offer office-based ulcer care, the majority prefer specialty consultation including podiatry, plastic surgery and dermatology. Despite their frequency, there is no clear consensus among providers as to the best treatment.

Interventions for treating leg ulcers in people with sickle cell disease

BACKGROUND

The frequency of skin ulceration makes it an important contributor to the morbidity burden in people with sickle cell disease. Many treatment options are available to the healthcare professional, although it is uncertain which treatments have been assessed for effectiveness in people with sickle cell disease.

OBJECTIVES

To assess the clinical effectiveness and safety of interventions for treating leg ulcers in people with sickle cell disease.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register.We searched LILACS (1982 to August 2012), the African Index Medicus (up to August 2012), ISI Web of Knowledge (1985 to August 2012), and the Clinical Trials Search Portal of the World Health Organization (August 2012). We checked the reference lists of all the trials identified. We also contacted those groups or individuals who may have completed relevant randomised trials in this area.Date of the last search of the Group's Haemoglobinopathies Trials Register: 25 May 2012.

SELECTION CRITERIA

Randomised controlled trials of interventions for treating leg ulcers in people with sickle cell disease compared to placebo or an alternative treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion. All three authors independently assessed the risk of bias of the included studies and extracted data.

MAIN RESULTS

Six studies met the inclusion criteria (198 participants with 250 ulcers). Each trial investigated a different intervention and within this review we have grouped these as systemic pharmaceutical interventions (L-cartinine, arginine butyrate, isoxsuprine) and topical pharmaceutical interventions (Solcoseryl(®) cream, RGD peptide dressing, topical antibiotics). Three interventions reported on the change in ulcer size (arginine butyrate, RGD peptide, L-cartinine). Of these, RGD peptide matrix significantly reduced ulcer size compared with a control group, mean reduction 6.60cm(2) (95% CI 5.51 to 7.69). Three trials reported on the incidence of complete closure (isoxsuprine, arginine butyrate, RGD peptide matrix). None reported a significant effect. No trial reported on: the time to complete ulcer healing; ulcer-free survival following treatment for sickle cell leg ulcers; quality of life measures; or incidence of amputation. There was no reported information on the safety of these interventions.

AUTHORS' CONCLUSIONS

There is evidence that a topical intervention (RGD peptide matrix) reduced ulcer size in treated participants compared to controls. This evidence of efficacy is limited by the generally high risk of bias associated with these reports.We planned to analyse results according to general groups: pharmaceutical interventions (systemic and topical); and non-pharmaceutical interventions (surgical and non-surgical). However, we were unable to pool findings due to the heterogeneity in outcome definitions, and inconsistency between the unit of randomisation and the unit of analysis. This heterogeneity, along with a paucity of identified trials, prevented us performing any meta-analyses.This Cochrane review provides some evidence for the effectiveness of one topical intervention - RGD peptide matrix. However, this intervention was assessed as having a high risk of bias due to inadequacies in the single trial report. Other included studies were also assessed as having a high risk of bias. We recommend that readers interpret the trial results with caution. The safety profile of the all interventions was inconclusive.

Livedoid vasculopathy associated with sickle cell trait: significant improvement on aspirin treatment

Livedoid vasculopathy (LV) is a chronic, recurrent, painful cutaneous disease manifesting as longstanding distal lower extremity ulcers that scar leaving stellate atrophic lesions known as 'atrophie blanche'. A significant number of cases have been associated with thrombophilic abnormalities. In this study, we describe, to the best of our knowledge, the first report of LV only associated with sickle cell trait with significant improvement on aspirin.

Laboratory and echocardiography markers in sickle cell patients with leg ulcers

Chronic leg ulcers are a debilitating complication of sickle cell disease, associated with increased morbidity and perhaps mortality that affect 8 to 50% of patients. We evaluated the characteristics of SCD patients with a history of leg ulceration, including hemolytic rate, estimated pulmonary artery systolic pressure, and other parameters in a cohort of 505 adults with SCD.

Ninety four subjects (18%) had either active ulcers at enrollment or history of leg ulceration. Patients affected were older and predominantly had homozygous SS, lower body mass index, and pulse oximetry, higher tricuspid regurgitation velocities, markers of hemolysis, serum uric acid and serum NT-proBNP, when compared to subjects without such history.

In this prospective cohort of adults with SCD, we confirm that leg ulcers are still frequent and are associated with elevated TRVand markers of hemolysis. We describe a novel association of leg ulcer with hyperuricemia and oxygen desaturation and suggest potential implications for uric acid as a marker of vascular dysfunction.

Leg ulcers in sickle cell disease

Sickle cell disease is a single amino acid molecular disorder of hemoglobin leading to its pathological polymerization, red cell rigidity that causes poor microvascular blood flow, with consequent tissue ischemia and infarction. The manifestations of this disease are protean.Among them, leg ulcers represent a particularly disabling and chronic complication, often associated with a more severe clinical course.Despite the fact that this complication has been recognized since the early times of SCD, there has been little improvement in the efficacy of its management and clinical outcome over the past 100 years. Recently, vasculopathic abnormalities involving abnormal vascular tone and activated, adhesive endothelium have been recognized as another pathway to end organ damage in sickle cell disease. Vasculopathy of sickle cell disease has been implicated in the development of pulmonary hypertension, stroke, leg ulceration and priapism, particularly associated with hemolytic severity, and reported in other severe hemolytic disorders. The authors present the proceedings from the Educational Session on Chronic leg ulcers in Sickle cell disease, held during the 4th Annual Sickle Cell Disease Research and Educational Symposium, on February 17, 2010 in Fort Lauderdale, Fla.

The Role of Nutrition in Sickle Cell Disease

Finding a widely available cure for sickle cell anemia (HbSS) still remains a challenge one hundred years after its discovery as a genetically inherited disease. However, growing interest in the nutritional problems of the disease has created a body of literature from researchers seeking nutritional alternatives as a means of decreasing morbidity and improving quality of life among HbSS patients. This review demonstrates that over the past 30 years the role of protein/energy deficiency in HbSS has been more clearly defined via direct measurements, leading to the concept of a relative shortage of nutrients for growth and development, despite apparently adequate dietary intakes. Although there is still a paucity of data supporting the efficacy of macronutrient supplementation, it is becoming clearer that recommended dietary allowances (RDAs) for the general population are insufficient for the sickle cell patient. A similar shortage is likely to be true for micronutrient deficiencies, including recent findings of vitamin D deficiency that may be associated with incomplete ossification and bone disease, which are well known complications of HbSS disease. We conclude that there is need for more effort and resources to be dedicated to research (including supplementation studies of larger sample size) aimed at establishing specific RDAs for HbSS patients, much like the specific RDAs developed for pregnancy and growth within the general population.

Emerging new drugs for wound repair

Every year, millions of people experience burns, suffer from nonhealing wounds, or have acute wounds that become complicated by infection, dehiscence or problematic scarring. Effective wound treatment requires carefully considered interventions often requiring multiple clinic or hospital visits. The resulting costs of wound care are staggering, and more efficacious and cost-effective therapies are needed to decrease this burden. Unfortunately, the expenses and difficulties encountered in performing clinical trials have led to a relatively slow growth of new treatment options for the wound management. Research efforts attempting to examine wound pathophysiology have been hampered by the lack of an adequate chronic wound healing model, and the complexity of the wound healing cascade has limited attempts at pharmacological modification. As such, currently available wound healing therapies are only partially effective. Therefore, many new therapies are emerging that target various aspects of wound repair and the promise of new therapeutic interventions is on the immediate horizon.

Leg Ulceration in Sickle Cell Disease: Medieval Medicine in a Modern World

Leg ulceration is now recognized as an important complication of sickle cell disease, especially of the SS genotype. Since there is no convincing evidence of delayed healing of operation scars or of wounds elsewhere in the body, it must be concluded that factors specific to the lower leg render patients prone to delayed healing at this site. Many lesions are traumatic in origin and since there is considerable variation in healing rates among the normal population, it is useful to define chronic leg ulceration on the basis of a minimal duration, which in Jamaican studies has required at least 3 months and sometimes 6 months before healing. This minimal duration avoids the difficulties of interpreting the significance of briefer lesions since the moment of final healing may be poorly defined (patients may conclude that a scab represents healing whereas small lesions persist beneath) and often goes undocumented as patients may not report and medical attendants may not enquire, the date of final healing.