Passive smoking and nasal biofilms in children

Passive smoking exposure is implicated in several childhood respiratory disorders, for example nasal mucosa damages.

In this study by Elwani et al. in 2021, the aim of the authors was to identify the biofilms presence in the nasal mucosa of children with household passive smoking exposure.

The study included 20 children (6-12 years old) with a positive history of prolonged exposure to household passive smoking (verified using parental questionnaires and recording the number of cigarettes consumed every day by parents, and using measurement of urinary cotinine level) who required inferior turbinate reduction or other procedures such as tonsillectomy.

The control group included 20 children who required similar surgical procedures but without passive smoking exposure history.

During the surgical procedure, an inferior turbinate biopsy was taken and the sample was examined with the scanning electron microscopy and the transmission electron microscopy.

The nasal mucosa of 11 children (among the 20 children with passive smoking exposure history) developed biofilms and on cultures 10 biofilms contained S. Aureus and 1 biofilm contained S. pneumoniae.

On the other hand, in the control group, only 1 child presented nasal mucosa with S. Aureus biofilm.

Despite the small number of patients included in the study, the difference between the two groups was statistically significant.

Furthermore, biofilms presence was related with the passive smoking exposure duration and urinary cotinine levels.

Other studies stressed that some components of tobacco smoke may trigger the formation of S. Aureus biofilms through oxidant-dependent mechanisms and a prolonged smoking exposure may provoke biofilm-related bacterial genes alterations which favour biofilms growth. 

Bibliography
Elwany et al. Passive smoking induces nasal biofilms in children. International Journal of Pediatric Otorhinolaryngology 146 (2021) 110755;
Kulkarni et al. Cigarettes Smoke increases Staphylococcus Aureus Biofilm Formation via Oxidative Stress. Infection and Immunity 2021 Volume 80 Number 11 p. 3804-3811;
Antunes et al. Molecular basis of tobacco-induced bacterial biofilms: an in vitro study. Otolaryngol Head Neck Surg. 2012 Nov;147(5):876-84.