Utility of Point-of-Care Lung Ultrasonography for Evaluating Acute Chest Syndrome in Young Patients With Sickle Cell Disease.

STUDY OBJECTIVE: Acute chest syndrome is a leading cause of mortality in patients with sickle cell disease (SCD). Because early detection of acute chest syndrome is directly tied to prognosis, young patients with SCD undergo countless chest radiography screenings throughout their lifetime for commonly occurring acute chest syndrome risk factors such as fever, chest pain, or cough. Chest radiography is not an ideal screening method because it is associated with radiation exposure, which accumulates with repeated imaging. Point-of-care lung ultrasonography is a nonradiating imaging modality that has been used to identify other lung pathology and may have a role in SCD. The goal of this study was to determine the accuracy of point-of-care lung ultrasound to identify an infiltrate suggestive of acute chest syndrome in patients with SCD compared to chest radiography as the gold standard. METHODS: This was a prospective observational study in 2 urban pediatric emergency departments to evaluate the accuracy of point-of-care lung ultrasonography in identifying patients with SCD who were aged 0 to 21 years and had an infiltrate suggestive of acute chest syndrome compared with chest radiography. Clinicians and trainees with point-of-care lung ultrasonographic training obtained informed consent and performed investigational point-of-care lung ultrasonography to evaluate for lung consolidation. A blinded point-of-care lung ultrasonographic expert reviewed results for quality assurance and agreement. Accuracy, sensitivity, specificity, likelihood ratios, and positive and negative predictive value were calculated for point-of-care lung ultrasonography test performance characteristics, with chest radiography as a reference standard. RESULTS: Point-of-care lung ultrasonography was performed on 191 SCD patients with a mean age of 8 years; 41% were female patients, and there was a 17% prevalence of acute chest syndrome. Accuracy of point-of-care lung ultrasonography to detected acute chest syndrome was 92%, sensitivity was 88%, and specificity was 93% compared with that for chest radiography. CONCLUSION: Point-of-care lung ultrasonography is a feasible alternative to chest radiography for screening for acute chest syndrome in young patients with SCD. Further studies are needed to determine how this test performs within clinical practice.

Association between plasma free haem and incidence of vaso-occlusive episodes and acute chest syndrome in children with sickle cell disease.

We tested the hypothesis that extracellular haem is linked to the incidence of acute complications of sickle cell disease (SCD). Using multivariable regression analysis, higher plasma free haem, but not total plasma haem, was associated with increased odds of vaso-occlusive crisis (VOC) [P = 0·028, odds ratio (OR); 2·05, 95% Confidence Interval (CI) = 1·08-3·89] and acute chest syndrome (ACS) [P = 0·016, OR; 2·56, CI = 1·19, 5·47], after adjusting for age and gender in children with SCD. These findings suggest that haem and factors that influence its concentration in plasma may be informative of the risk of VOC and ACS in SCD patients.

Sickle Cell Disease with Cyanotic Congenital Heart Disease: Long-Term Outcomes in 5 Children.

Sickle cell disease is a risk factor for cerebrovascular accidents in the pediatric population. This risk is compounded by hypoxemia. Cyanotic congenital heart disease can expose patients to prolonged hypoxemia. To our knowledge, the long-term outcome of patients who have combined sickle cell and cyanotic congenital heart disease has not been reported. We retrospectively reviewed patient records at our institution and identified 5 patients (3 girls and 2 boys) who had both conditions. Their outcomes were uniformly poor: 4 died (age range, 12 mo-17 yr); 3 had documented cerebrovascular accidents; and 3 developed ventricular dysfunction. The surviving patient had developmental delays. On the basis of this series, we suggest mitigating hypoxemia, and thus the risk of stroke, in patients who have sickle cell disease and cyanotic congenital heart disease. Potential therapies include chronic blood transfusions, hydroxyurea, earlier surgical correction to reduce the duration of hypoxemia, and heart or bone marrow transplantation.