The microcirculatory disfunction plays an important role in the development of pneumonia, determining the clinical course and development of complications. The purpose of the study is the assessment of lung microcirculation disturbance on the different stages of the community-acquired pneumonia and distinguishing it from a post heart attack pneumonia. Materials and methods. 135 patients were radiologically explored. They were admitted to the radiological department with inflammatory signs for the assessment of microcirculation disturbances caused by the pneumonia. We investigated the obtained results. Results. The paper elucidates the stages of community-acquired pneumonia by the results of radiological exploration. In the absence of respiratory diseases, the alterations of lung parenchyma structure were caused by pleural effusion (r=0.71) and pneumonic infiltration zones (posterior parts of the lungs (0.74) and lingular segments (r=0.64)). The microcirculatory disturbances were elicited and counted in automatic mode. The residual alterations were reliably more often observed in the patients with chronic bronchitis. The level of D-dimer was not pathognomic but it was reliably higher in the patients with the PATE (p<0.05). Conclusions. The ambiguous interpretation of disk-shaped atelectasis, avascular sites and areas of pneumonic infiltration of lung tissue with MSCT, requires the SPECT or combined SPECT-CT studies allowing to detect clear triangular microcirculation defects characteristic of pulmonary embolism. The site of inflammatory infiltration effects on the appearance of pulmonary fibrosis. So, the zones of fibrosis can be found in the upper lobes, posterior parts of the lungs and lingular segments reliably more often. The technique for automatic processing of radiological lung exploration allows to get the quantitative assessment the microcirculatory disfunction and the lack of perfusion. It is essential for evaluation of the pathology dynamics and severity and for assessment of the treatment efficiency.