Clinical diagnostics of pneumonia caused by atypical microorganisms

Since 2023, there has been an increase in the incidence of pneumonia caused by atypical bacteria, primarily Mycoplasma pneumoniae. Atypical pathogens have several common features: they are not cultured by conventional microbiological methods, are obligate or facultative intracellular parasites, often cause extrapulmonary symptoms and, importantly for clinicians, due to the absence of a peptide cell wall, they do not respond to β-lactam antibiotics.

The aim of the study was to identify clinical and laboratory features of pneumonia associated with M. pneumoniae and C. pneumoniae in children hospitalized in an infectious diseases hospital.

Materials and methods. A retrospective analysis of 355 medical records of children hospitalized in an infectious diseases hospital with a diagnosis of atypical pneumonia was conducted. The patients were divided into groups: 298 patients with mycoplasma pneumonia, 22 children with chlamydial pneumonia and 35 children with a combination of M.pneumoniae and C.pneumoniae.

Results and conclusions. Modern atypical pneumonia in hospitalized children is characterized by an acute onset with the development of fever (79%, 280/355), asthenia (90%, 319/355) and cough (94.5%, 336/355). Dyspnea develops in 30%, 105/355, respiratory failure in most cases is moderate, only 13%, 48/355 of hospitalized patients need respiratory support. More often, the process is right-sided (46.8%, 166/355), auscultatory signs are present in 82%, 293/355 children. Extrapulmonary manifestations in the form of damage to the gastrointestinal tract and skin are recorded in an average of 7–15%.

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