Abstract: Objective Conduct a comparative analysis of the precision between pathogen culture and smear microscopy for the diagnosis of chronic suppurative otitis media combined with fungal infections of the external auditory canal. This study also aims to evaluate the therapeutic efficacy of triamcinolone acetonide and econazole nitrate cream, evaluate the safety of its application in patients with perforation of the tympanic membrane, and the results of tympanic membrane repair and surgery after control of fungal infections. Methods A total of 44 patients diagnosed with chronic suppurative otitis media with tympanic membrane perforation combined with fungal infection of the external auditory canal were included in this study. Pathogenic bacteria culture and smear microscopy were performed to compare the positivity rate of the two diagnostic methods, and pure tone audiometry was also performed to evaluate hearing levels. After treatment with triamcinolone acetonide and econazole nitrate cream, smear microscopy and pure tone audiometry were repeated to assess the effect of treatment. The control group was divided into a fungal group and a control group according to whether they were infected or not with fungi. The control group consisted of 35 patients with chronic suppurative otitis media who underwent endoscopic repair of the tympanic membrane. For the 35 cases of patients with chronic suppurative otitis media who underwent otoscopic repair of the tympanic membrane, the fungal group performed 32 cases of otoscopic repair of the tympanic membrane after negative microscopic examination, comparing the healing rate of the tympanic membrane, healing time, dry ear time, and hearing between the two groups. Results The positive rate of fungal infection detected by pathogenic bacteria culture was 73.7%, of which common fungal species included Aspergillus and filamentous fungi, combined with bacterial infection(26.3%). The positive rate of smear microscopy was 77.5% and the difference between the positive rates of the two methods of examination was not statistically significant(P=0.695). After treatment with the application of triamcinolone acetonide and econazole nitrate cream, the patients' fungi were completely controlled by otoscopic examination and smear microscopy, the smear microscopy was negative and the difference in the results of pure tone audiometry before and after treatment was not statistically significant(P<0.001). The repair of the tympanic membrane was performed after the fungal infection was controlled and there were no statistically significant differences in the healing rate of the tympanic membrane(P>0.999), the healing time(P=0.593)and the dry ear time(P=0.945)between the two groups compared to the simple perforation group. Conclusion Smear microscopy and pathogenic bacteria culture have a high positive rate. Triamcinolone acetonide and econazole nitrate cream are effective in treating patients with tympanic membrane perforation combined with fungal infection of the external auditory canal without significant ototoxicity. The success rate of tympanic membrane repair surgery in patients did not change significantly after control of fungal infection.

Key words: Fungal infection of the external auditory canal, Tympanic membrane perforation, Smear microscopy, Pathogen culture, Triamcinolone acetonide and econazole nitrate cream