Environmental and non-infectious factors in the aetiology of pharyngitis (sore throat).

ABSTRACT

OBJECTIVES: The aim of this review is to examine the causes, pathophysiology and experimental models of non-infectious pharyngitis (sore throat). INTRODUCTION: The causes of sore throat can be infectious (viruses, bacteria, and fungi) or non-infectious, although the relative proportion of each is not well documented. METHODS: A PubMed database search was performed for studies of non-infectious sore throat. RESULTS AND CONCLUSIONS: Non-infectious causes of sore throat include physico-chemical factors, such as smoking, snoring, shouting, tracheal intubation, medications, or concomitant illness; and environmental factors including indoor and outdoor air pollutants, temperature and humidity, and hazardous or occupational irritants. The pathophysiology underlying non-infectious sore throat is largely uncharacterised, although neurogenic inflammation looks to be a promising candidate. It is likely that there will be individual disposition factors or the coincidence of more than one irritant with possible--up to now unknown--interactions between them. Therefore, experimental models with defined conditions and objective endpoints are needed. A new model using cold dry air to directly induce pharyngeal irritation in humans, with pharyngeal lavage to measure biomarkers, may provide a useful tool for the study of mechanisms and treatment of non-infectious sore throat.