PADI4 Gene Polymorphism As a Risk Factor for Acute Chest Syndrome in Sickle Cell Anemia Patients

Abstract Introduction: Sickle cell anemia (SCA) is a chronic inflammatory disease with heterogeneous clinical features and the reasons for the heterogeneity of the clinical manifestations has not been fully elucidated. New mediators of the pathogenesis of SCA described recently include the formation of Neutrophil Extracellular Traps (NETs), which may contribute to the amplification of inflammation via the production of pro-inflammatory mediators. Peptidylarginine Deiminase 4 (PADI4) is a critical regulator of NETosis by mediating histone citrullination, an essential step for the generation of NETs. There appears to be a relationship between PADI4 gene polymorphisms and the pathophysiology of other inflammatory diseases in which NETosis seems to be relevant. Our aim was to investigate the association of PADI4 gene polymorphisms [rs874881(G>C), rs1748033(T>C), rs11203366(G>A), rs11203367 (T >C), rs2240340 (T>C)], which have been previously associated with increased PADI4 mRNA stability and with some clinical manifestations in cohorts of SCA patients. Methods: The study included 194 SCA patients (93 males and 101 females with mean age 33.29 ± 9.54 years) being followed up at the Hematology and Hemotherapy Foundation of Pernambuco (HEMOPE), Recife, Brazil. PADI4 gene polymorphisms were performed by Polymerase Chain Reaction (PCR) and their products were sequenced using the Big Dye Terminator Cycle Sequencing Ready Reaction Kit v3.1 (Applied Biosystems, CA, USA). These results obtained were compared with the clinical data obtained from the patients' records. Ethical approval was obtained from Ethics Committee of HEMOPE and all patients gave informed consent. Results: The frequencies of the genotypes found were as follows: rs874881 (22.2% GG, 50.5% GC, 27.3% CC); rs1748033 (17% TT, 42.3% TC, 40.7% CC); rs11203366 (21.1% GG, 50% GA, 28.9% AA); rs11203367 (20.6% TT, 49.5% TC, 29.9% CC); rs2240340 (24.7% TT, 46.4% TC, 28.9% CC). The distribution of the genotypes was in accordance with the Hardy-Weinberg equilibrium (p > 0.05). Twenty-four patients (12.4%) presented with a history of acute chest syndrome (ACS), 27 (13.9%) with stroke, 168 (86.6%) with vaso-occlusive crisis (VOC), and 81 (47.8%) with leg ulcers (LU). No association was observed between the polymorphisms studied and the history of LU, VOC and stroke in the patients (p > 0.05). However, for rs 874881 and 1748033 with the G and T alleles, respectively, were associated with a higher risk of ACS (OR: 2.96, p = 0.02 and OR: 4.75, p = 0.01, respectively). Conclusion: In the present study, we found an association between the wild type alleles (rs874881G and rs1748033T) and a history of ACS in our cohort of SCA patients. There is need for future studies on these polymorphisms in larger cohorts of SCA patients to affirm this association. Disclosures No relevant conflicts of interest to declare.

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Association of MBL2 polymorphism with Leg Ulcers Development in Sickle Cell Anemia Patients

Blood ◽

10.1182/blood.v124.21.4912.4912 ◽

2014 ◽

Vol 124 (21) ◽

pp. 4912-4912

Author(s):

Marcos André Cavalcanti Bezerra ◽

Isabela Cristina Farias ◽

Diego Arruda Falcão ◽

Igor de Farias Domingos ◽

Luana Laranjeira Prado ◽

...

Keyword(s):

Sickle Cell ◽

Sickle Cell Anemia ◽

Conflicts Of Interest ◽

Clinical Manifestations ◽

Monogenic Disease ◽

Prior History ◽

Leg Ulcers ◽

Immune Disorder ◽

History Of ◽

Mbl Deficiency

Abstract Leg ulcers are the most common clinical manifestations of sickle cell anemia (SCA), a monogenic disease with huge clinical diversity among patients. They affect 8% to 10% of SCA patients, reaching a percentage greater than 50% in patients residing in tropical areas. These ulcers occur due to vascular occlusion, tissue hypoxia, hemolysis and genetic factors, presenting a slow healing, high recurrence rate and huge susceptibility to infection. Recently, some studies have shown a positive relationship between the complement system and the development of some vascular diseases and injuries such as leg ulcers in non-SCA patients. Mannan-binding lectin (MBL) is an important component of the humoral innate immune system, and MBL possesses several characteristics indicating that it may play an essential role in wound healing; modulating inflammation and contributing to the clearance of microorganisms and apoptotic cells. In a recent study of chronic leg and foot ulcer patients, serum MBL levels were significantly different between wounds of different etiologies, with chronic venous leg ulcers patients having a higher frequency of MBL deficiency. Polymorphisms in the MBL2 are associated with a reduction in the MBL protein serum levels, increasing risk of developing leg ulcers and also the maintenance of these wounds, compromising the integrity of the immune defence and its response to potential invading pathogens. Here, we aimed to determine the frequency of polymorphisms in the promoter region -221 (Y / X) and -550 (H / L) and exon 1 of the MBL2 and assess the clinical impact of these variants in a northeastern Brazilian SCA population who presented leg ulcers. Two-hundred seventy-five unrelated SCA patients were included. According the leg ulcers presence, the total cohort was classified in patients presenting current or prior history of leg ulcers (n=100) and SCA patients above 18 years with no history of leg ulcers (n=175). Molecular analysis was performed by qPCR. Our population was in Hardy-Weinberg equilibrium. The allelic frequency of haplotypes associated with high MBL production (HYA, LYA) was 54.5% for cases and 62.9% in controls. The genotypes related to low MBL production (HYO, LYO) in cases and controls was 27.5% and 18.6%, respectively. The frequency of genotype related to intermediate MBL production (LXA) was 18% in cases and 18.5% in controls. We had no statistically significant results when we analyzed only the polymorphisms (P>0.05). However, the phenotypic analysis between high and low MBL production revealed that patients with leg ulcers have lower MBL protein levels (P=0.019). We focused specifically on a possible role of MBL deficiency on healing complications, based on the facts that MBL deficiency is the most common immune disorder, and that a common causality for prolonged healing of these ulcers is infection or colonization by bacteria. In our study, MBL deficiency appears to increase the risk of developing leg ulcers in SCA patients. Disclosures No relevant conflicts of interest to declare.

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Targeted Education after an Emergency Department Visit Increases Hydroxyurea Initiation in Children with Sickle Cell Anemia

Blood ◽

10.1182/blood.v130.suppl_1.868.868 ◽

2017 ◽

Vol 130 (Suppl_1) ◽

pp. 868-868

Author(s):

Sarah Kappa ◽

Lydia Pecker ◽

Deepika S. Darbari ◽

Robert Nickel

Keyword(s):

Emergency Department ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

Conflicts Of Interest ◽

National Health System ◽

Clinic Visit ◽

Acute Chest Syndrome ◽

Hemoglobin F ◽

History Of ◽

One Year

Abstract Introduction: Hydroxyurea decreases many complications of sickle cell anemia (SCA) but is underused in treatment-eligible patients. Barriers to hydroxyurea initiation occur on the health care system, provider, and patient level. Novel strategies to increase hydroxyurea use in patients with SCA are needed. To address this challenge at our center, we implemented the Quick Start Hydroxyurea Initiation Project (Q-SHIP). Methods: Patients with SCA were eligible to participate in Q-SHIP if they presented to the Children's National Health System (CNHS) emergency department (ED) for pain or acute chest syndrome and were not taking hydroxyurea. Patients <9 months old, on chronic transfusions, pregnant, or not followed by CNHS hematology were excluded. Eligible patients were referred to a weekly Q-SHIP clinic visit focused on hydroxyurea education and were offered initiating treatment at the visit's conclusion. Participants completed a pre-session questionnaire, discussed hydroxyurea with a hematologist using a handbook developed by CNHS, and watched videos featuring patients and parents of children with SCA sharing their experience with hydroxyurea. Subjects were classified as starting hydroxyurea if they had a clinic visit for hydroxyurea monitoring within 3 months of participation in a Q-SHIP session. Results: Over 13 months (2/1/2016 - 3/31/2017) 65 eligible patients participated in Q-SHIP a median of 5 days (IQR 2, 20 days) after ED or hospital discharge. Although 44% (28/64) of participants reported no previous hydroxyurea offer, provider clinic documentation indicated that 61% (17/28) of these families had declined a previous hydroxyurea offer. After Q-SHIP, 55% (36/65) of participants started hydroxyurea. Subjects who started hydroxyurea after Q-SHIP were similar to those who did not, except subjects who started were more likely have a history of an intensive care unit admission (Table 1). After a median follow-up of 11 months, 81% (29/36) of participants who started hydroxyurea after Q-SHIP continued on therapy. Among Q-SHIP participants continuing treatment, mean corpuscular volume increased by a median of 8.6 fL (IQR +5.4, +17.7, p<0.0001) and hemoglobin F increased by a median of 5.8% (IQR +3.0, +11.3, p<0.001). One year after implementation of Q-SHIP, the proportion of treatment-eligible patients with SCA who presented to the ED with pain or ACS who were receiving hydroxyurea increased; February 2016: 56% (32/57) vs. February 2017: 73% (43/59), p=0.059. Conclusion: Addressing indications for hydroxyurea therapy in a clinic encounter exclusively for this purpose soon after a SCA complication is a meaningful time to meet with families of children with SCA to initiate treatment. Disclosures No relevant conflicts of interest to declare.

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Correlation of Iron Levels with Asthma and Lung Function in Pediatric Patients with Sickle Cell Anemia

Blood ◽

10.1182/blood-2020-136661 ◽

2020 ◽

Vol 136 (Supplement 1) ◽

pp. 12-12

Author(s):

Yusra D Shaikh ◽

Nataly Apollonsky ◽

Bruce Bernstein

Keyword(s):

Sickle Cell ◽

Sickle Cell Anemia ◽

Serum Iron ◽

Pediatric Patients ◽

Pulmonary Complications ◽

Acute Chest Syndrome ◽

Iron Level ◽

Obstructive Sleep ◽

History Of ◽

Hb S

Introduction:Significant morbidity and mortality in patients with sickle cell disease (SCD) is attributed to the pulmonary sequalae of the disease. Patients with SCD often suffer airway hyper-reactivity, acute chest syndrome (ACS), chronic lung disease, pulmonary hypertension (PHTN), and obstructive sleep apnea (OSA). Recent literature has provided evidence supporting the strong association between asthma and airway hyper-reactivity in SCD. One of the factors linked to chronic inflammation and asthma is iron status. The present study examined whether iron levels are associated with pulmonary complications in pediatric patients with SCD. Method:Through retrospective review of electronic medical records (EMR) we evaluated patients with diagnosis of asthma and SCD. All patients with available PFT (3/21/2013-3/11/2020) and iron studies were included in the analysis. Chi square and ANOVA tests were used to explore relationships of respiratory conditions with lab data and relevant medical history. Results:The analysis reviewed information of 100 patients with SCD -- 56 males and 44 females The sample population had the following genotypes: 63% Hemoglobin (Hb) SS, 23% Hb SC, 2% Hb S Beta Zero Thalassemia, and 12% Hb S Beta Thalassemia. 38% of these patients were receiving treatment via hydroxyurea. The results generated found that patients with a large airway obstruction (LAO) had a marginally statistically significantly higher serum iron level than those with no LAO (p=0.067.) Patients with homozygous Hb S disease were four times as likely to have a history of ACS (p=0.004) than those without and were marginally significantly more likely to be SS and SB0Thal (p=0.052). Patients with history of ACS had a significantly higher mean iron saturation and lower total iron binding capacity (TIBC.) Patients with PHTN had significantly higher serum iron levels (p=0.029). Conclusion:Our findings reveal that while iron might play a more significant role in the development of PHTN and ACS in patients with SCD, the role in asthma is borderline in our sample. These findings, although of borderline statistical significance p=0.067, are clinically noteworthy. These results may open a new window for therapy targeted at maintaining iron in normal physiologic ranges to decrease pulmonary complications in patients with sickle cell anemia. Further studies with larger samples are necessary to clarify the meaning of our marginally significant findings. Disclosures No relevant conflicts of interest to declare.

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Serum Transferrin: An Independent Predictor of Mortality in Sickle Cell Anemia

Blood ◽

10.1182/blood.v118.21.2126.2126 ◽

2011 ◽

Vol 118 (21) ◽

pp. 2126-2126

Author(s):

Zahra Pakbaz ◽

Mariana E Hildesheim ◽

Shoaib Alam ◽

Darlene Allen ◽

Caterina Minniti ◽

...

Keyword(s):

Endothelial Dysfunction ◽

Sickle Cell ◽

Serum Ferritin ◽

Sickle Cell Anemia ◽

Conflicts Of Interest ◽

Independent Predictor ◽

Stable Condition ◽

Acute Chest Syndrome ◽

Serum Transferrin ◽

Significant Difference

Abstract Abstract 2126 Introduction: Serum ferritin (SF), the most convenient marker of iron burden in sickle cell anemia (SCA), is potentially confounded by effects of inflammation in SCA. Serum transferrin (STF) has been described as one of the independent predictors of elevated tricuspid regurgitant velocity (TRV) in SCA. Therefore in this report we investigate the potential predictive role of STF in morbidity and mortality of individuals with SCA. Methods: Patients with sickle cell disease documented by high-pressure liquid chromatography were eligible for the study. Four hundred and sixty SCA patients were recruited in this study from the community through multimedia advertisements, community outreach, and regional clinics. All evaluated patients were screened by history taking, physical examination, laboratory studies, and transthoracic echocardiography. All patients provided written informed consent. The advertisements and protocol were approved by the institutional review boards of the National Heart, Lung, and Blood Institute and Howard University. Only outpatients in stable condition were included; patients who had had a vaso-occlusive crisis within the previous two weeks or an episode of acute chest syndrome within the previous four weeks were excluded. Results: Two hundred and sixty two participants with HbSS were included in the data analysis. Forty-seven percent were male. Median age was 32 years old. Median TRV in this cohort was 2.4 m/s. Forty nine percent of participants had TRV≥2.5 m/s and 19% had TRV≥3 m/s. Patients with lower STF (<164 mg/dl) were older (p=0.01), had more blood transfusions in the past (p<0.0001) and did not have more complications of sickle disease (priapism, acute chest syndrome, leg ulcers or emergency room visits, all p>0.05), but all-cause death rate was higher (22% vs. 6%, p=0.0001). Hemoglobin, CRP, alkaline phosphatase, uric acid, placenta growth factor (<0.001), SF and iron saturation were found to be higher and kidney function was worse. Patients with lower STF level were also more likely to have TRV≥3.0 m/s (32% vs. 13%, p<0. 001) but there was no significant difference in BNP and ejection fraction. Patients with lower STF had endothelial dysfunction, as indicated by a blunted forearm blood flow (FBF) response to infusion of acetylcholine into the brachial artery (p<0.01). Among age, gender, BNP, TRV,GFR,WBC, STF, systolic blood pressure and fetal hemoglobin, the Cox proportional analysis of mortality found TRV, GFR and STF the independent significant predictors of mortality in this cohort. Kaplan-Meier survival curve showed that patients with transferrin <164 mg/dl had significantly lower survival (p<0.001). Conclusion: In this cohort of adults with sickle cells anemia, STF is found to be an independent predictor of endothelial dysfunction, high TRV and mortality. It may be a more sensitive predictor than serum ferritin. We propose that iron overload may induce a state of endothelial dysfunction that is a risk factor for clinical vasculopathy and death. Disclosures: No relevant conflicts of interest to declare.

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Pulmonary Function in Children with Sickle Cell Anemia Following Treatment with Hydroxyurea.

Blood ◽

10.1182/blood.v112.11.1435.1435 ◽

2008 ◽

Vol 112 (11) ◽

pp. 1435-1435 ◽

Cited By ~ 1

Author(s):

Elizabeth Record ◽

Tamara New ◽

Randall Brown ◽

LeRoy Graham ◽

R. Clark Brown

Keyword(s):

Pulmonary Function ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

Pulmonary Function Tests ◽

Pulmonary Complications ◽

Acute Chest Syndrome ◽

P Value ◽

Chronic Injury ◽

History Of ◽

Abnormal Pulmonary Function

Abstract Background: Pulmonary function is particularly susceptible to acute and chronic injury occurring in patients with sickle cell anemia (SCA). Acute Chest Syndrome (ACS), a common and potentially fatal complication of SCA, can be the cause or the consequence of abnormal pulmonary function (Siddiqui & Ahmed, 2003). Use of hydroxyurea therapy (HU) is increasing for children with recurrent pulmonary complications, following the findings that HU reduces risk of ACS in adults (Charache et al, 1995). How HU may improve pulmonary function in children with SCA is still ill-defined. The purpose of this study was to assess the change observed on serial pulmonary function tests (PFT) for children prescribed HU for abnormal pulmonary function. Methods: Over 240 children with pulmonary complications, such as acute chest syndrome, reactive airway disease, and chronic hypoxia, have been evaluated in the Sickle Cell Pulmonary Clinic at Children’s Healthcare of Atlanta since beginning in July 2000. As part of the Clinic’s standard of care, PFT were routinely attempted on children over the age of 5. A retrospective review of PFT results was done for the children with SCA and prior abnormal PFT. Children were included in the HU cohort (+HU) if repeat PFTs were available following > 3 months on HU therapy and if time on HU did not include frequent RBC transfusions. Children without history of HU therapy (−HU) were selected for comparison. PFTs were performed on a standard plethysmograph. Paired t-test was used to evaluate observed differences. Results: Thirty-one children with prior abnormal PFT had test before and following prescription of HU. Their mean age was 12.6 (range 6–20) years and mean duration of HU was 21 (range 4–47) months at the time of the repeat PFT. Hematologic changes expected on HU occurred for all 31 children. Twenty-four children followed for abnormal PFT had no history of HU (−HU) and matched the +HU group by gender, age (mean 12.3, range 7–19 years), duration followed at time of repeat PFT (mean 19, range 3–66 months; p=0.36), and initial hematologic parameters. Spirometry findings changed for +HU group, and remained stable for −HU group. Mean FVC and FEV1 values improved significantly on HU, when compared to initial (PreHU) PFT and to −HU controls. Conversion to a normal PFT, as interpreted by a pediatric pulmonologist masked to treatment status, occurred in 18 (58%) and 2 (8%) children in the +HU and −HU groups, respectively. Table 1: Serial PFT and hematologic parameters according to HU exposure −HU (n=24) +HU (n=31) Initial Repeat # PreHU Repeat 1 % predicted value for age, sex and height of subject. 2Mean (SD) #No significant changes compared to Initial, p > 0.05. *P value < 0.001 compared to PreHU; ++P value < 0.001 compared to −HU repeat. PFT parameter 1 TLC 88 (13.6)2 85 (11.7) 85 (13.4) 90 (13.5) FVC 78 (9.8) 79 (9.9) 75 (12.6) 90 (13.2)*,++ FEV1 75 (9.6) 74 (12.2) 72 (11.4) 86 (10.2)*,++ FEF 25-75 75 (22) 72 (28.0) 77 (23.4) 79 (26.8) FEV1/FVC (%) 85(6.7) 82 (9.8) 87 (11.8) 86 (11.1) Pulse oximetry (%) 95 (3.1) 96 (2.4) 94 (4.4) 97 (2.8)* WBC (x103/ul) 14 (3.8) 13 (2.9) 13.02 (2.9) 9.0 (2.1) *,++ Hb (g/dl) 8.0 (0.1) 8.0 (0.9) 7.8 (1.1) 9.1 (1.3) *,++ MCV (fl) 84 (9.2) 85 (10.0) 87.3 (8.1) 101.2 (10.1) *,++ HbF (%) 4.3 (1.5) 5.2 (5.2) 6.0 (3.8) 14.0 (7.3) *,++ Conclusions: Serial PFTs showed improved pulmonary function, following initiation of HU therapy in children with prior abnormal PFT. Routine PFT assessments of children prescribed HU may serve as an objective measure of clinical response in children with SCA and pulmonary complications. These results will help in the design of future prospective studies examining the clinical benefits of HU therapy for children at risk for long-term pulmonary complications.

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Prevalence of Sickle Cell Anemia In Eastern India

Blood ◽

10.1182/blood.v116.21.4822.4822 ◽

2010 ◽

Vol 116 (21) ◽

pp. 4822-4822

Author(s):

Abhijit Chakraborty ◽

Jayasri Basak ◽

Deboshree Majumdar ◽

Soma Mukhopadhyay ◽

Sagnik Chakraborty ◽

...

Keyword(s):

Risk Factor ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

West Bengal ◽

Conflicts Of Interest ◽

Acute Chest Syndrome ◽

Red Cell ◽

Cell Disease ◽

Cell Counts

Abstract Abstract 4822 Background: Sickle cell disease is an inherited disorder of hemoglobin synthesis. This is due to replacement of Valine for Glutamic Acid in position six of the Beta globin chain of hemoglobin. This genetic alteration yields unstable RBC which lasts for 10–20 days. In stressful conditions the cells become sickle shaped and get lysed. There are about 20 million people with sickle cell disease in India. During January 2009- May2010 camps were held in various parts of West Bengal, Jharkhand, Chattisgarh. Along with various mutations of thalassemia, we also observed sickle cell anemia among them. This triggered our interest to study the spectrum of the sickle mutation co-inheritant with different mutations such as Homozygous Sickle Cell, Sickle Cell-Beta0 Thalassemia, Sickle Cell-Beta+ Thalassemia, Severe β+ thalassemia genes, Moderate β+ thalassemia genes, Mild β+ thalassemia genes Sickle cell-HbE Thalassaemia, Sickle cell-HPFH Thalassaemia, in said part of India. Since Indian patients with SS disease had higher hemoglobin, red cell counts and higher HbF levels and lower HbA2, MCHC, MCV, and reticulocyte counts, hence a high hemoglobin is a risk factor for painful crises and may also be a risk factor for avascular necrosis of the femoral head, proliferative sickle retinopathy, and acute chest syndrome. Methods: We have screened 332 individuals in eastern part of India during the period January 2009- May 2010. 3ml of peripheral blood was collected in EDTA vial from each individual. NESTROFT (Naked Eye Single Tube Red Cell Osmotic Fragility Test) was performed on spot. Then Complete Blood Count was done within 24 hours of collection. HPLC (High Performance Liquid Chromatography) was performed to identify the samples for confirmation. In our observation in case of sickle cell anaemia HbF (Fetal haemoglobin), Hb (haemoglobin), MCV (mean corpuscular volume) values ranges between 0–10 %, ≤7-10g/dl, 65–90fl respectively. ARMS (Amplification Refractory Mutation System) PCR (polymerase chain reaction) was done to confirm the mutation. Result: Conclusion: Of the total samples collected in the camps held at various places of Jharkand, Chattisgarh & West Bengal 87 of them was carriers of sickle cell anemia. There was 7 homozygous (SS), 14 sickle beta, 12 double heterozygous for HPFH (High Persistance of Fetal Hemoglobin) & sickle cell anemia. In conclusion, the manifestations of sickle cell disease are influenced by a variety of other genetic and environmental factors. The occurrence of the disease against different genetic and environmental backgrounds provides experimental models that contribute to understanding the variability in clinical and hematological expression of the disease. Disclosures: No relevant conflicts of interest to declare.

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Interleukin 8 Level, Reticulocyte Counting and aPTT Ratio in Brazilian Sickle Cell Anemia Patients with Leg Ulcers

Blood ◽

10.1182/blood.v118.21.4835.4835 ◽

2011 ◽

Vol 118 (21) ◽

pp. 4835-4835

Author(s):

Magnun N N Santos ◽

Eliel Wagner Faber ◽

Dulcinéia Martins Albuquerque ◽

Romulo Tadeu Dias Oliveira ◽

Marcos André Cavalcanti Bezerra ◽

...

Keyword(s):

Gene Expression ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

Plasma Levels ◽

Conflicts Of Interest ◽

Organ Damage ◽

Northeastern Brazil ◽

Leg Ulcers ◽

Increased Risk ◽

History Of

Abstract Abstract 4835 Background: Sickle cell anemia (SCA) is characterized by a chronic inflammatory state in which oxidative stress, particularly in the endothelium, exerts a strong influence on the pathogenesis of vaso-occlusion and may be implicated in patients' clinical heterogeneity and survival. It has been suggested that the cytokine production profile of cells involved in the immune response may vary among patients with SCA. Leg ulcers (LU) represent a severe complication in these patients, and this condition has been associated with specific end-organ damage and an increase in morbidity and mortality. Recent studies have shown that venous obstruction, endothelial dysfunction, coagulopathy and infections are implicated in the complex pathogenesis of LU. Aims: To determine IL-1β, IL-6 and IL-8 plasma levels and gene expression rates as well as hematological and coagulation parameters and correlate these with the history of LU in adult SCA patients followed up at HEMOPE, in the state of Pernambuco, northeastern Brazil. Methods: Peripheral blood samples from 92 patients (median age 27 years; 42 female; 52 male; all Afro-descendants) in the steady state who had been diagnosed with SCA (HbSS), had not received a transfusion and were not using hydroxyurea were analyzed. Plasma levels of cytokines were determined by ELISA, and the gene expression rates by qRT-PCR. The patients' clinical and laboratorial characteristics were obtained from their medical charts. Statistical analysis was performed using the SAS System for Windows version 9.2. Results: Median age was higher in patients with a history of LU than in those without a history (33.1 vs. 28.4; p = 0.04). Although no statistically significant (p = 0.5) differences in IL-8 gene expression rates were observed, IL-8 plasma levels were significantly higher in patients with a history of LU than in patients without a history (23.8 vs. 7.7; p = 0.01) (Figure 1). Thus, patients with high levels of IL-8 had an increased risk for the occurrence of leg ulcers (OR = 1.01; 95% CI = 1.00–1.02). The ROC curve showed that IL-8 levels higher than 8.55 pg/mL could indicate the presence of LU (accuracy = 71.6%; sensitivity = 73.7%; specificity = 68.5%). The laboratory tests revealed reticulocyte counts and activated partial thromboplastin time (aPTT) ratios (R) that were significantly higher in patients with a history of LU than in those without a history (11.8 vs. 8.4, p = 0.01; 1.1 vs. 0.9, p = 0.04, respectively). Both the higher reticulocyte counts and R values were associated with increased risk for the occurrence of leg ulcers in these patients (OR = 1.12, 95% CI = 1.02 – 1.20; OR = 24.28, 95% CI = 1.20 – 486.09, respectively). Conclusion: In this study, patients who had had LU at some time in their lives showed significantly higher IL-8 levels, reticulocyte counts and R values than patients who had never had LU. Our results therefore suggest a relationship between the parameters described above and LU in patients with SCA. These parameters could perhaps be used, in association with different genetic modulators that may contribute to different clinical phenotypes observed in this disease, as markers of this clinical manifestation of SCA or of a propensity to develop it. Financial Support: CAPES (Brazil)/FAPESP/CNPq/INCTS Disclosures: No relevant conflicts of interest to declare.

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Sickle Cell Disease

10.1093/med/9780190678333.003.0033 ◽

2018 ◽

Author(s):

Ann Ng ◽

Erin S. Williams

Keyword(s):

African American ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

Sickle Cell Trait ◽

Organ Damage ◽

Acute Chest Syndrome ◽

Cell Disease ◽

Systemic Involvement ◽

History Of

Sickle cell anemia (sickle cell disease) is a common hemoglobinopathy with anywhere from 90,000 to 100,000 Americans affected. This chronic condition has a predominance in populations of African descent, occurring in approximately 1 out of 365 African American births, compared to 1 out of 16,300 Hispanic births. The sickle cell trait can be detected in 1 of 13 African American births. One of the most common complications associated with sickle cell anemia, vaso-occlusive crises by sickled cells, results in severe pain. Other issues associated with this condition include acute chest syndrome, lung infections, end organ damage, and stroke. With improvements in the management and prevention of pain crises, infection, and other systemic involvement, these patients are living longer, thus increasing the potential for surgical needs. Whether it is for routine surgeries or surgeries that are due to the natural history of the disease; the pediatric anesthesiologist must be knowledgeable of the management of these patients in order to prevent morbidity and mortality.

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Sickle Cell Leg Ulcers Are Associated with Hyperuricemia, Hemolysis, Pulmonary Hypertension and Death.

Blood ◽

10.1182/blood.v114.22.2583.2583 ◽

2009 ◽

Vol 114 (22) ◽

pp. 2583-2583

Author(s):

Caterina P. Minniti ◽

Mariana Hildesheim ◽

Vandana Sachdev ◽

Darlene Allen ◽

Oswaldo Castro ◽

...

Keyword(s):

Pulmonary Hypertension ◽

Uric Acid ◽

Serum Uric Acid ◽

Sickle Cell ◽

Conflicts Of Interest ◽

Elevated Serum ◽

Categorical Variables ◽

Acute Chest Syndrome ◽

Leg Ulcers ◽

History Of

Abstract Abstract 2583 Poster Board II-560 Background: Leg ulceration is a common, debilitating complication of sickle cell disease (SCD), affecting 8 to 50% of patients, and recently found to be associated with the hemolytic phenotype. We evaluated the relationship of leg ulceration history with estimated pulmonary artery systolic pressure, hemolytic rate and other clinical characteristics in a cohort of 396 adults with SCD. Materials and methods: All SCD patients were enrolled in a NHLBI-approved protocol and were screened for pulmonary hypertension with echocardiography at steady state. We collected a detailed past medical history, as well as a comprehensive set of laboratory tests. Comparisons between patients with and without a history of leg ulcers were made using Wilcoxon rank sum tests to compare medians of continuous variables. Associations between categorical variables and leg ulcer history in two groups were tested using the chi-square test of independence. Results: Eighteen % of all subjects had a history of leg ulceration. Patients affected were older, predominantly had homozygous SCD, and had markers of significantly more severe hemolysis, including low hemoglobin and high reticulocyte counts, LDH and AST. They also had a significantly higher prevalence of elevated tricuspid regurgitation velocities (TRV≥2.5 m/sec, 56% vs. 40%, p=0.02; TRV≥3 m/sec, 22% vs. 12%, p=0.006). High serum uric acid and lower serum albumin were significantly associated with a history of leg ulcers. A self-reported history of hepatitis also was associated with leg ulceration. None of the other parameters evaluated were significantly associated with leg ulceration, including history of pain, acute chest syndrome, stroke or priapism. Significantly, patients with a history of leg ulcers were more likely to have died by the time of data analysis (21% vs. 9%, P=0.02). Discussion: These data in SCD patients with a history of leg ulcers provide the first demonstration of an association with elevated serum uric acid and confirmation of published associations with elevated pulmonary pressures and markers of hemolytic severity. The uric acid association is more significant than that for serum creatinine or urea nitrogen, suggesting that uric acid is more than simply a marker of renal dysfunction. In patients without SCD, there is a growing literature implicating uric acid as a possible cause of hypertension and a marker of risk for cardiovascular disease, pulmonary hypertension, and early mortality. This is particularly interesting, in view of the epidemiological relationship between leg ulcers and pulmonary hypertension demonstrated here and previously by others. The results continue to support linkage of leg ulcers and pulmonary hypertension to a hyperhemolytic -vasculopathy subphenotype of SCD. Disclosures: No relevant conflicts of interest to declare.

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Impact of Hyperfiltration during Early Childhood on the Natural History of Albuminuria in Pediatric Sickle Cell Anemia

Blood ◽

10.1182/blood-2018-99-115063 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 8-8

Author(s):

Jeffrey Lebensburger ◽

Lee Hilliard ◽

Thomas H. Howard ◽

Inmaculada Aban ◽

Daniel Feig

Keyword(s):

Early Childhood ◽

Natural History ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

Conflicts Of Interest ◽

First Episode ◽

Event Analysis ◽

Time To Event ◽

History Of ◽

The Mean

Abstract Introduction: Pediatric patients with Sickle Cell Anemia (SCA) are at risk for developing albuminuria. Hyperfiltration precedes the development of albuminuria in patients with diabetes but the natural history of hyperfiltration on the progression to albuminuria has not been studied in children with SCA. Methods: We have enrolled 185 participants with HbSS or SB0 thalassemia in a prospective pediatric cohort study evaluating progression to chronic kidney disease; the mean current age of participants in this cohort is 14 years. We have abstracted 817 urine microalbumin creatinine measurements and 891 estimations of GFR (eGFR) by Cystatin C. Abnormal urine albumin/creatinine is defined as >30mg/g. We defined persistent albuminuria as two abnormal spot urine microalbumin/creatinine measurements over three consecutive measurements and intermittent albuminuria as one abnormal urine measurement with two consecutive repeat measurement as normal. We performed descriptive and univariate statistics to characterize the natural history of the development of albuminuria. Next, as standard of care definitions of hyperfiltration (>140 ml/min/1.87) are not appropriate in SCA during early childhood (4-10 years of age), we a priori defined hyperfiltration as an eGFR ≥180 ml/min/1.87. We categorized patients with hyperfiltration during early childhood if the mean eGFR was >180 ml/min/1.87. We abstracted the mean white blood cell count (WBC), hemoglobin (Hb), and SCA therapy during early childhood and performed estimates of the odds ratio and used chi-squared test to compare the proportion of those who progressed to persistent albuminuria. Finally, we performed time to event analysis to obtain the estimated Kaplan-Meier curves for participants with and without hyperfiltration and used logrank test to compare their survival distributions. Results: Among the 185 participants, 55 participants (30%) were identified with at least one episode of albuminuria and 130 patients (70%) have not yet developed an episode of albuminuria. Among the 55 participants identified with an albuminuria event, 36 participants (66%) are categorized as having persistent albuminuria while 19 patients (34%) demonstrated intermittent or only one episode of albuminuria. The mean age at the identification of a first albuminuria event was 11.0 years (range 2-18 years). Comparing patients that progressed to persistent vs intermittent albuminuria, we identified no significant differences for age at first episode of albuminuria (13.2 vs 11.9 years, p=0.3) or type of SCA modifying therapy at first episode of albuminuria (p=0.4). We identified 90 participants with eGFR obtained between 4-10 years; 39 (43%) participants were categorized with hyperfiltration and 51 participants had a mean eGFR < 180 ml/min/1.87. Nine of the 39 (23%) participants categorized with hyperfiltration have progressed to develop persistent albuminuria as compared to 3 (6%) of the 51 without hyperfiltration progressed to persistent albuminuria; hyperfiltration was associated with a 4.8 higher odds of developing persistent proteinuria. (p=0.02). The mean eGFR during early childhood was also significantly higher among participants that progressed to albuminuria (186 vs 169 ml/min/1.87, p=0.04). We identified no significant impact of mean WBC (p=0.13), mean hemoglobin (p=0.07), or SCA therapy (p=0.22) in this subset of patients on progression to persistent albuminuria. As the current age of participants impacts identifying albuminuria outcomes, we performed a time to event analysis; participants identified with hyperfiltration during early childhood develop persistent albuminuria at an earlier age than participants without persistent albuminuria (logrank p=0.004). Finally, while persistent albuminuria was significantly associated with hyperfiltration during early childhood, we did not identify a difference in eGFR between patients with and without albuminuria during adolescence (Figure 1). Conclusion: Although 30% of patients with SCA will develop an episode of albuminuria during childhood, only 19% of cohort participants developed persistent albuminuria. Early hyperfiltration is predictive for developing albuminuria and therapies should target reducing hyperfiltration in the first decade of life. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

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