S.V. KHALIULLINA¹, M.R. GATAULLIN², V.A. POZDNYAK¹, S.T. AGLIULLINA¹, YU.A. TYURIN^1, 3, L.A. KALIMULLINA^1, 2, A.I. SADYKOV¹, N.V. MATIEVSKAYA⁴

 ¹Kazan State Medical University, Kazan

²Republic Clinical Hospital for Infectious Diseases named after Prof. A.F. Agafonov, Kazan

³Kazan Research Institute of Epidemiology and Microbiology, Kazan

⁴Grodno State Medical University, Grodno, Republic of Belarus

 Contact details:

Khaliullina S.V. — MD, Associate Professor, Professor of the Department of Childhood Infections

Address: 49 Butlerov St., 420112 Kazan, Russian Federation, tel.: +7 (843) 267-80-06, e-mail: svekhal@mail.ru

The purpose — to identify clinical and laboratory differences between community-acquired pneumonias caused by typical bacterial pathogens and Mycoplasma pneumoniae in children in order to develop a predictive model for differential diagnosis.

Material and methods: a retrospective study compared 442 patients with Mycoplasma pneumoniae (n = 298) and bacterial pneumonia (n = 144) based on clinical and laboratory indicators. All participants were children over one year of age, hospitalized in an Infectious Diseases Department with radiologically confirmed community-acquired pneumonia between January and December 2024. A logistic regression analysis was used to develop a predictive model for determining pneumonia etiology.

Results and conclusion. Bacterial and mycoplasma pneumonias were distinguished by a combination of the following features: more pronounced asthenic syndrome (lethargy, decreased activity), rhinorrhea, pharyngeal hyperemia, signs of exudative tonsillitis (tonsillar exudate), refusal to drink, abnormal lung auscultation findings (harsh or diminished breath sounds), higher fever at admission, elevated C-reactive protein (CRP), and lower mean corpuscular hemoglobin (MCH). The identified predictive features were used to develop an online calculator, which is user-friendly and freely available. However, this model is currently proposed as a pilot version and requires validation in larger studies.

Key words: pneumonia, respiratory infection, Mycoplasma pneumoniae, differential diagnosis, children.

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