Features of whooping cough in adolescents: clinical, diagnostic, and immunological aspects

Objective. To analyze the clinical, diagnostic, and immunological characteristics of pertussis in adolescents. Patients and methods. The analysis is based on observations of 90 adolescents hospitalized in 2023–2024 with a diagnosis of pertussis. In 64 (71.1%) children, pertussis was observed in combination with other respiratory diseases. To verify the primary diagnosis, polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) methods were used; to diagnose acute respiratory viral infection, PCR was used, and for mycoplasma infection, the ELISA method was used. Immunological studies included assessment of lymphocyte subpopulation composition, interferon system, serum IgE content, and spectrum of antibodies against Bordetella pertussis. Results. Whooping cough in adolescents was characterized by a typical clinical symptom complex, but it was noteworthy that patients were admitted to the hospital mainly in the late stages of the disease: 60.4% of patients were hospitalized in the 5th week, 39.6% in the 4th week of the disease. At the same time, 83 (92.2%) patients had a moderate form of the disease, 5 (5.6%) had a severe form, and 2 (2.2%) had a mild form. The most characteristic immune status abnormalities were low NK cell (CD3–CD16+CD56+) counts, detected in 53.7% of patients. The CD4/CD8 ratio was below reference values in 58.5% of adolescents. Changes in the interferon system mainly affected the ability of lymphocytes to produce interferon-γ: low values were detected in 63.4% of patients. Conclusion. The analysis demonstrates that pertussis in adolescents typically manifests as moderate forms of the disease, with severe forms being recorded in recent years. Noteworthy are the prolonged prodromal period, the pronounced psychoemotional component of the whooping cough symptom complex, and the high frequency of mixed infections. Immunological studies have revealed changes in the cellular link and interferon system, as well as an increase in serum IgE in a significant number of patients. Key words: whooping cough, cough, adolescents, acute respiratry viral infections, lymphocyte subpopulations, interferon protection