Obstructive sleep apnoea (OSA) in children is a prevalent sleep disorder, and is characterised by repetitive complete or partial upper airway obstruction during sleep. It is an important disease as it is associated with a large spectrum of end-organ morbidities.

Adenotonsillar hypertrophy is the commonest cause of OSA in children, however, the cause of the lymphoid tissue hypertrophy in some individuals but not the others remains unknown. To address the cellular heterogeneity and immune cell involvement in adenotonsillar hypertrophy, here, we propose to employ single-cell sequencing analysis to identify the cell-specific expression patterns associated with the disease, which will enhance our understanding of the pathogenesis of tonsillar hypertrophy in children with OSA and may provide directions for development of novel therapy.

Inclusion Criteria:

Case: Chinese children aged 6-11 years old with habitual snoring (≥3 nights per week) and polysomnography (PSG) confirmed OSA (obstructive apnoea hypopnoea index (OAHI) of ≥1/hour), with adenotonsillar hypertrophy and clinical indications for adenotonsillectomy will be recruited as cases.

Control: Non-OSA subjects (with PSG OAHI <1/hour) who undergo adenotonsillectomy for other reasons such as recurrent tonsillitis.

Exclusion Criteria:

Previous upper airway surgery, genetic or syndromal disease, congenital or acquired neuromuscular disease, congenital or acquired immunodeficiency, known metabolic syndrome, craniofacial abnormalities.

Case: Chinese children aged 6-11 years old with habitual snoring (≥3 nights per week) and polysomnography (PSG) confirmed OSA (obstructive apnoea hypopnoea index (OAHI) of ≥1/hour), with adenotonsillar hypertrophy and clinical indications for adenotonsillectomy will be recruited as cases.

Control: Non-OSA subjects (with PSG OAHI <1/hour) who undergo adenotonsillectomy for other reasons such as recurrent tonsillitis.