Lung imaging during acute chest syndrome in sickle cell disease: computed tomography patterns and diagnostic accuracy of bedside chest radiograph

Abstract

IntroductionThe lung computed tomography (CT) features of acute chest syndrome (ACS) in sickle cell disease patients is not well described, and the diagnostic performance of bedside chest radiograph (CR) has not been tested. Our objectives were to describe CT features of ACS and evaluate the reproducibility and diagnostic performance of bedside CR. Methods We screened 127 consecutive patients during 166 ACS episodes and 145 CT scans (in 118 consecutive patients) were included in the study. Results Among the 145 CT scans, 139 (96%) exhibited a new pulmonary opacity and 84 (58%) exhibited at least one complete lung segment consolidation. Consolidations were predominant as compared with ground-glass opacities and atelectasis. Lung parenchyma was increasingly consolidated from apex to base; the right and left inferior lobes were almost always involved in patients with a new complete lung segment consolidation on CT scan (98% and 95% of cases, respectively). Patients with a new complete lung segment consolidation on CT scan had a more severe presentation and course as compared with others.

Bedside Lung Ultrasound During Acute Chest Syndrome in Sickle Cell Disease

“…7 Each lung was divided into 6 regions (the upper and lower parts of the anterior, lateral, and posterior regions), using a cephalocaudal mid-axillary line and a transversal hilar line for delineation, and the apex, mediastinum border, diaphragm, and external limit of the rib cage as external landmarks, as previously described. 12 …”

“…7 The 12 lung regions that were explored by LU and CT were also analyzed using CR, using the same anatomic landmarks (apex, mediastinum border, diaphragm, external limit of the rib cage, mid-axillary line, and transversal hilar line), with posterior lung regions being defined as those with radiologic signs erasing the mediastinum border (“silhouette sign”), as previously described. 12 …”

“…7 Briefly, consolidation was defined as an homogeneous increase in pulmonary parenchymal attenuation that obscured the margins of vessels and airway walls (an air bronchogram might be present). Ground-glass opacity was defined on CR as an area of hazy increased lung opacity, usually extensive, within which margins of pulmonary vessels may be indistinct; on CT scans, it was defined as hazy increased opacity of the lung, with preservation of bronchial and vascular margins.…”

Year in review 2014. Paediatric and adult clinical studies

“…Acute chest syndrome in SCD comes in many radiographic forms. Mekontso Dessap et al 19 found that consolidation was more severe in the apex and was more prevalent than ground glass change or atelectasis. Its presence was associated with a worse prognosis.…”

Radiographic patterns of acute chest syndrome

“…While discussing our paper,2 the reviewer seems to have misinterpreted our results when saying that consolidation is more severe in the apex of adult sickle cell disease patients with acute chest syndrome. In fact, CT and bedside chest radiography showed that lung parenchyma was increasingly consolidated from apex to base 2. This distribution is in accordance with previous studies,3 4 but may vary with age, with young children having more upper and middle lobe disease, contrarily to adult patients 3…”