Angiogenic and Inflammatory Markers of Cardiopulmonary Changes in Children and Adolescents with Sickle Cell Disease

Background: Pulmonary hypertension and left ventricular diastolic dysfunction are complications of sickle cell disease. Pulmonary hypertension is associated with hemolysis and hypoxia, but other unidentified factors are likely involved in pathogenesis as well. Design and Methods: Plasma concentrations of three angiogenic markers (fibroblast growth factor, platelet derived growth factor-BB [PDGF-BB], vascular endothelial growth factor [VEGF]) and seven inflammatory markers implicated in pulmonary hypertension in other settings were determined by Bio-Plex suspension array in 237 children and adolescents with sickle cell disease at steady state and 43 controls. Tricuspid regurgitation velocity (which reflects systolic pulmonary artery pressure), mitral valve E/Edti ratio (which reflects left ventricular diastolic dysfunction), and a hemolytic component derived from four markers of hemolysis and hemoglobin oxygen saturation were also determined. Results: Plasma concentrations of interleukin-8, interleukin-10 and VEGF were elevated in the patients with sickle cell disease compared to controls (P≤0.003). By logistic regression, greater values for PDGF-BB (P = 0.009), interleukin-6 (P = 0.019) and the hemolytic component (P = 0.026) were independently associated with increased odds of elevated tricuspid regurgitation velocity while higher VEGF concentrations were associated with decreased odds (P = 0.005) among the patients with sickle cell disease. These findings, which are consistent with reports that PDGF-BB stimulates and VEGF inhibits vascular smooth muscle cell proliferation, did not apply to E/Etdi. Conclusions: Circulating concentrations of angiogenic and pro-Inflammatory markers are altered in sickle cell disease children and adolescents with elevated tricuspid regurgitation velocity, a subgroup that may be at risk for developing worsening pulmonary hypertension. Further studies to understand the molecular changes in these children are indicated

Tricuspid regurgitation velocity and other biomarkers of mortality in children, adolescents and young adults with sickle cell disease in the United States: The PUSH study

In the US, mortality in sickle cell disease (SCD) increases after age 18- 20- years. Biomarkers of mortality risk can identify patients who need intensive follow- up and early or novel interventions. We prospectively enrolled 510 SCD patients aged 3- 20- years into an observational study in 2006- 2010 and followed 497 patients for a median of 88- months (range 1- 105). We hypothesized that elevated pulmonary artery systolic pressure as reflected in tricuspid regurgitation velocity (TRV) would be associated with mortality. Estimated survival to 18- years was 99% and to 25- years, 94%. Causes of death were known in seven of 10 patients: stroke in four (hemorrhagic two, infarctive one, unspecified one), multiorgan failure one, parvovirus B19 infection one, sudden death one. Baseline TRV - ¥2.7 m/second (>2 SD above the mean in age- matched and gender- matched non- SCD controls) was observed in 20.0% of patients who died vs 4.6% of those who survived (P =- .012 by the log rank test for equality of survival). The baseline variable most strongly associated with an elevated TRV was a high hemolytic rate. Additional biomarkers associated with mortality were ferritin - ¥2000- μg/L (observed in 60% of patients who died vs 7.8% of survivors, P <- .001), forced expiratory volume in 1 minute to forced vital capacity ratio (FEV1/FVC) <0.80 (71.4% of patients who died vs 18.8% of survivors, P <- .001), and neutrophil count - ¥10x109/L (30.0% of patients who died vs 7.9% of survivors, P =- .018). In SCD children, adolescents and young adults, steady- state elevations of TRV, ferritin and neutrophils and a low FEV1/FVC ratio may be biomarkers associated with increased risk of death.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155951/1/ajh25799_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155951/2/ajh25799.pd

Clinical correlates of acute pulmonary events in children and adolescents with sickle cell disease

Objectives We aimed to identify risk factors for acute pulmonary events in children and adolescents in the Pulmonary Hypertension and the Hypoxic Response in SCD ( PUSH ) study. Methods Patients with hemoglobin SS ( n  = 376) and other sickle cell genotypes ( n  = 127) aged 3–20 yrs were studied at four centers in a cross‐sectional manner. A subgroup ( n  = 293) was followed for a median of 21 months (range 9–35). Results A patient‐reported history of one or more acute pulmonary events, either acute chest syndrome ( ACS ) or pneumonia, was obtained in 195 hemoglobin SS patients (52%) and 51 patients with other genotypes (40%). By logistic regression, history of acute pulmonary events was independently associated with patient‐reported history of asthma ( P  3 severe pain episodes in the preceding 12 months ( P  = 0.002), higher tricuspid regurgitation velocity ( TRV ) ( P  = 0.028), and higher white blood cell ( WBC ) count ( P  = 0.043) among hemoglobin SS patients. History of acute pulmonary events was associated with >3 severe pain episodes ( P  = 0.009) among patients with other genotypes. During follow‐up, 43 patients (15%) had at least one new ACS episode including 11 without a baseline history of acute pulmonary events. History of acute pulmonary events (odds ratio 5.0; P  < 0.0001) and younger age (odds ratio 0.9; P  = 0.007) were independently associated with developing a new episode during follow‐up. Conclusions Asthma history, frequent pain, and higher values for TRV and WBC count were independently associated with history of acute pulmonary events in hemoglobin SS patients and frequent pain was associated in those with other genotypes. Measures to reduce pain episodes and control asthma may help to decrease the incidence of acute pulmonary events in SCD .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98784/1/ejh12118.pd

Comparison of approaches to determine echocardiographic outcomes for children with latent rheumatic heart disease

Background Screening programmes using echocardiography offer opportunity for intervention through identification and treatment of early (latent) rheumatic heart disease (RHD). We aimed to compare two methods for classifying progression or regression of latent RHD: serial review method and blinded, side-by-side review.Methods A four-member expert panel reviewed 799 enrolment (in 2018) and completion (in 2020) echocardiograms from the GOAL Trial of latent RHD in Uganda to make consensus determination of normal, borderline RHD or definite RHD. Serial interpretations (enrolment and completion echocardiograms read at two different time points, 2 years apart, not beside one another) were compared with blinded side-by-side comparisons (enrolment and completion echocardiograms displayed beside one another in random order on same screen) to determine outcomes according to prespecified definitions of disease progression (worsening), regression (improving) or no change. We calculated inter-rater agreement using Cohen’s kappa.Results There were 799 pairs of echocardiogram assessments included. A higher number, 54 vs 38 (6.8% vs 4.5%), were deemed as progression by serial interpretation compared with side-by-side comparison. There was good inter-rater agreement between the serial interpretation and side-by-side comparison methods (kappa 0.89). Disagreement was most often a result of the difference in classification between borderline RHD and mild definite RHD. Most discrepancies between interpretation methods (46 of 47, 98%) resulted from differences in valvular morphological evaluation, with valves judged to be morphologically similar between enrolment and final echocardiograms when compared side by side but classified differently on serial interpretation.Conclusions There was good agreement between the methods of serial and side-by-side interpretation of echocardiograms for change over time, using the World Heart Federation criteria. Side-by-side interpretation has higher specificity for change, with fewer differences in the interpretation of valvular morphology, as compared with serial interpretation

Elevated tricuspid regurgitant jet velocity in children and adolescents with sickle cell disease: association with hemolysis and hemoglobin oxygen desaturation

An elevated echocardiography-determined tricuspid regurgitant jet velocity predicts high systolic pulmonary artery pressure and early mortality in adults with sickle cell disease. The study provides evidence for independent associations of elevated jet velocity with hemolysis and oxygen desaturation in children and adolescents with sickle cell disease

Differences in the clinical and genotypic presentation of sickle cell disease around the world

Sickle cell disease (SCD), caused by a mutation in the β-globin gene HBB, is widely distributed in malaria endemic regions. Cardiopulmonary complications are major causes of morbidity and mortality. Hemoglobin SS (Hb SS) represents a large proportion of SCD in the Americas, United Kingdom, and certain regions of Africa while higher proportions of hemoglobin SC are observed in Burkina Faso and hemoglobin Sβ-thalassemia in Greece and India. Coinheritance of α-thalassemia and persistence of hemoglobin F production are observed in highest frequency in certain regions of India and the Middle East. As confirmed in the PUSH and Walk-PHaSST studies, Hb SS, absence of co-inheriting alpha-thalassemia, and low hemoglobin F levels tend to be associated with more hemolysis, lower hemoglobin oxygen saturations, greater proportions of elevated tricuspid regurgitant jet velocity and brain natriuretic peptide, and increased left ventricular mass index. Identification of additional genetic modifiers will improve prediction of cardiopulmonary complications in SCD. © 2013 Elsevier Ltd