Description and evaluation of a simple method for microbiological studies on otitis externa

Area of Science:

• Microbiology
• Diving Medicine
• Clinical Diagnostics

Background:

• External otitis is common in divers.
• Accurate identification of causative agents is crucial for effective treatment, especially in remote locations.

Purpose of the Study:

• To describe and evaluate a simple cultural method for identifying bacteria and yeasts responsible for external otitis in divers.
• To assess the efficacy of the Urotube dip-slide system compared to traditional culture methods.

Main Methods:

• Utilized a commercial dip-slide system (Urotube) with ear swabs.
• Compared Urotube results with traditional agar plate cultures.
• Incubated cultures at 37°C for ≥18 hours.
• Evaluated reproducibility and stability of growth patterns using reference strains and clinical isolates.

Main Results:

• The Urotube method demonstrated stable and reproducible growth patterns for bacterial and yeast species.
• A consistent semiquantitative relationship was observed between dip-slide growth and agar plate cultures.
• Identical findings were obtained from normal and infected ear canals using both Urotube and traditional methods.
• Favorable practical experience was reported in offshore settings.

Conclusions:

• The Urotube dip-slide method offers a rapid, simple, and reliable approach for identifying external otitis pathogens in divers.
• This method is particularly valuable in isolated areas lacking laboratory facilities, potentially improving therapeutic speed and choice.