Clinical cases of legionelliosis in the Krasnodar region during the new coronavirus infection COVID-19 pandemic: difficulties in diagnosis

Abstract

The high incidence of community-acquired pneumonia during the COVID-19 pandemic requires early differential diagnosis because of the differences in patient management techniques. Among community-acquired pneumonias, legionelliosis deserves special attention. The difficulty of clinical diagnosis of legionellosis during the COVID-19 pandemic leads to untimely prescription of specific antibacterial therapy, which worsens the prognosis. This study presents clinical examples that draw the attention of specialists to the clinical, laboratory, and radiological features of legionellosis and to the important role of epidemiological data in the differential diagnosis of legionellosis with COVID-19. A feature of the described clinical cases was as follows: late diagnosis with hospitalization on days 7–10 of illness in patients with increased body mass index, severe bilateral polysegmental pneumonia with the formation of a cavity and multirow bullae in the lungs, presence of proteinuria, increased levels of urea and/or creatinine, and lymphopenia. In all cases, the patients had history of staying in air-conditioned rooms and traveling by train. Compute tomography diagnostics described a localization that is not typical for COVID-19, manifestation from areas of consolidation with a symptom of air bronchography, presence of pleural effusion, discrepancy between the intensity of changes from the disease onset, and severity of the patient’s condition. For the specific diagnosis of legionellosis, testing for Legionella spp. To determine the legionella antigen in the urine is recommended upon hospital admission for all patients with severe community-acquired pneumonia.