Bacterial and Fungal Infections Promote the Bone Erosion Progression in Acquired Cholesteatoma Revealed by Metagenomic Next-Generation Sequencing

An acquired cholesteatoma generally occurs as a consequence of otitis media and eustachian tube dysfunction. Patients with acquired cholesteatoma generally present with chronic otorrhea and progressive conductive hearing loss. There are many microbes reportedly associated with acquired cholesteatoma. However, conventional culture-based techniques show a typically low detection rate for various pathogenetic bacteria and fungi. Metagenomic next-generation sequencing (mNGS), an emerging powerful platform offering higher sensitivity and higher throughput for evaluating many samples at once, remains to be studied in acquired cholesteatoma. In this study, 16 consecutive patients from January 2020 to January 2021 at the Second Affiliated Hospital of Zhejiang University School of Medicine (SAHZU) were reviewed. We detected a total of 31 microbial species in patients, mNGS provided a higher detection rate compared to culture (100% vs. 31.25%, p = 0.000034). As the severity of the patient’s pathological condition worsens, the more complex types of microbes were identified. The most commonly detected microbial genus was Aspergillus (9/16, 56.25%), especially in patients suffering from severe bone erosion. In summary, mNGS improves the sensibility to identify pathogens of cholesteatoma patients, and Aspergillus infections increase bone destruction in acquired cholesteatoma.

Trismus and TMJ disorders as first clinical manifestations in an intracranial acquired cholesteatoma

Intracranial extension of acquired cholesteatoma is a rare occurrence that can develop secondary to trauma, chronic otitis media or acquired aural cholesteatoma. The most commonly observed symptoms are headache and hearing loss. The authors report on a rare case of intracranial cholesteatoma presenting with atypic symptoms: swelling and temporomandibular joint disorders.

Expression of tumor necrosis factor Alpha, interleukin-1 and matrix metalloproteinase-9 and pathomorphological changes in acquired middle ear cholesteatoma

Introduction. The inflammatory mediators play a central role in the pathogenesis of the inflammatory process of the middle ear and cholesteatoma from the aspect of initiating and maintaining the inflammatory response to infection and lesion. The aim of the study was to examine if the presence of acquired cholesteatoma could predict pathomorphological changes of the tympanic cavity mucosa in relation to the control tissue of the inflamed middle ear mucosa and to examine and compare the expression levels of tumor necrosis factor-alpha (TNF-a), interleukin-1 (IL-1) and matrix metalloproteinase 9 (MMP-9) with pathomorphological changes in the middle ear mucosa in chronic otitis media (COM), with and without acquired cholesteatoma (AC). Methods. The immunohistochemical study included 178 patients of both sexes, aged 5 to 75, who underwent microsurgical treatment of COM from 2015 to 2018. Patients were divided into two groups based on the presence or absence of AC of the middle ear: 97 with cholesteatoma (CCOM) and 81 without cholesteatoma (COM). Samples of the perimatrix of AC and inflamed middle ear mucosa were taken intraoperatively. The condition of the tympanic cavity mucosa was examined by otomicroscopy exploration intraoperatively. The expression levels of TNF-a, IL-1 and MMP-9 were determined by immunohistochemical analysis. Results. The difference in the percentage distribution of patients according to the condition of the tympanic cavity mucosa between both groups was statistically significant (p <0.01) where in the COM group the highest frequency was 43.2% of patients with mucosal hypertrophy, and in the CCOM 56.7% with granulations. With highly positive expression of TNF-R2 and IL-1, a higher probability of the presence of mucosal hypertrophy and granulations can be expected, and with highly positive expression of MMP-9 the presence of granulations. Conclusion. Acquired middle ear cholesteatoma is a statistically significant predictor of the occurence of mucosal hypertrophy and granulations in the tympanic cavity in relation to the control tissue of the inflamed middle ear mucosa. The high expression of TNF-R2, IL-1 and MMP-9 shows a statistically significant association with the presence of granulations and mucosal hypertrophy in acquired middle ear cholesteatoma which may have clinical significance in the evaluation and prognosis of the disease.