Lung aeration in experimental malaria-associated acute respiratory distress syndrome by SPECT/CT analysis

Abstract

Malaria-associated acute respiratory distress syndrome (ARDS) is an inflammatory disease causing alveolar-pulmonary barrier lesion and increased vascular permeability characterized by severe hypoxemia. Computed tomography (CT), among other imaging techniques, allows the morphological and quantitative identification of lung lesions during ARDS. This study aims to identify the onset of malaria-associated ARDS development in an experimental model by imaging diagnosis. Our results demonstrated that ARDS-developing mice presented decreased gaseous exchange and pulmonary insufficiency, as shown by the SPECT/CT technique. The pulmonary aeration disturbance in ARDS-developing mice on the 5 th day post infection was characterized by aerated tissues decrease and nonaerated tissue accumulation, demonstrating increased vascular permeability and pleural effusion. The SPECT/CT technique allowed the early diagnosis in the experimental model, as well as the identification of the pulmonary aeration. Notwithstanding, despite the fact that this study contributes to better understand lung lesions during malaria-associated ARDS, further imaging studies are needed.

Experimental Models to Study the Pathogenesis of Malaria-Associated Acute Respiratory Distress Syndrome

“…The integrity of alveolar capillaries was disrupted and mostly leukocytes and iRBCs were often found congested within these capillaries. Lung function test coupled with sophisticated imaging procedures [i.e., X-ray, single-photon emission computed tomography/computed tomography (SPECT/CT) and magnetic resonance imaging (MRI)] conducted on conscious infected mice exhibited pulmonary aeration disturbance, reduced respiration frequency, obstructed airways and increasing timely pulmonary opacities ( Ortolan et al., 2014 ; Claser et al., 2019 ; Quirino et al., 2020 ). Ultrastructural analysis using transmission electron microscopy (TEM) in the lung of PbA-infected DBA/2 mice that died of MA-ARDS, provided evidence of eosinophilic hyaline membranes occasionally found to line the alveolar septa ( Aitken et al., 2014 ).…”