External auditory canal pH in chronic otitis externa

Area of Science:

• Otolaryngology
• Dermatology
• Microbiology

Background:

• Otitis externa can become chronic, with altered external auditory canal skin pH suggested as a contributing factor.
• Previous studies noted pH changes in acute otitis externa, but their role in chronicity requires further investigation.

Purpose of the Study:

• To compare the external auditory canal pH in individuals with chronic otitis externa versus a control group.
• To investigate the correlation between external auditory canal pH and the severity of chronic otitis externa.
• To explore the relationship between age, external auditory canal pH, and chronic otitis externa severity.

Main Methods:

• Prospective control study comparing age/sex-matched chronic otitis externa patients (without current exacerbation) and healthy controls.
• Measurement of external auditory canal skin pH and body skin pH.
• Assessment of chronic otitis externa severity using a multiparameter scoring system.

Main Results:

• Significantly higher external auditory canal pH was observed in the chronic otitis externa group compared to controls (P < 0.004).
• No difference in body skin pH was found between groups.
• A positive correlation existed between higher external auditory canal pH and increased chronic otitis externa severity (r = 0.562; P < 0.02).
• Younger patients exhibited more severe chronic otitis externa (r = -0.813; P < 0.001) and higher ear canal pH (r = -0.550; P < 0.02).

Conclusions:

• Alkaline ear canal skin pH is identified as a local risk factor for the progression to chronic otitis externa.
• The severity of chronic otitis externa is linked to higher ear canal pH.
• Younger individuals with chronic otitis externa present with greater severity and higher ear canal pH.