Informativity of laboratory diagnostics of pertussis in modern conditions

Relevance. Pertussis, despite long-term mass vaccination, remains an urgent health problem, which is largely due to the difficulties of clinical diagnosis, especially in young children and with atypical forms of the disease.

Aims. To identify factors influencing the diagnostic performance of the molecular genetic method (PCR) and enzyme-linked immunosorbent assay (ELISA) in laboratory diagnosis of pertussis in children and adults in 2024–2025.

Materials and methods. The study was based on clinical analysis and analysis of medical records of patients diagnosed with pertussis hospitalized in an infectious diseases hospital in Moscow. Laboratory diagnostics were carried out by PCR and ELISA methods, taking into account the age of patients, the duration of the disease and the severity of the clinical course.

Results. It has been established that the diagnostic effectiveness of the methods significantly depends on the age and timing of the examination. PCR was shown to be highly informative in children under 1 year of age (92.4 ± 2.4 %), while in children over 1 year of age in 29.7 ± 4.3 % of cases (p < 0.001). The diagnostic significance of ELISA increased by the age of patients (in children under 1 year of age, diagnostically significant levels of anti-pertussis antibodies were detected in 29.0 ± 3.1 % of cases, then in children over 1 year of age in 85.6 ± 3.3 % of cases (p < 0.001)). A high PCR efficiency was established in weeks 1–3 of the disease in children under 1 year of age (88.9 ± 3.2 %), while at weeks 4–5 there was a decrease (to 60.8 ± 10.2 %). A correlation was found between the severity of the clinical course and the effectiveness of PCR (80.8 % for moderate forms and 52.6 % for lungs, p < 0.001). ELISA is highly effective in adults (97.3 %). Age-related features of the humoral immune response were revealed, characterized by the predominance of IgM antibodies in young children and the formation of a complex antibody response in older children.

Conclusion. The results obtained confirm the feasibility of a differentiated approach to choosing a method for laboratory diagnosis of pertussis, taking into account the patient's age and the duration of the disease. 

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