Mycological study on cholesteatoma keratin obtained during primary mastoid surgery

Review of potential medical treatments for middle ear cholesteatoma

Middle ear cholesteatoma (MEC), is a destructive, and locally invasive lesion in the middle ear driven by inflammation with an annual incidence of 10 per 100,000. Surgical extraction/excision remains the only treatment strategy available and recurrence is high (up to 40%), therefore developing the first pharmaceutical treatments for MEC is desperately required. This review was targeted at connecting the dysregulated inflammatory network of MEC to pathogenesis and identification of pharmaceutical targets. We summarized the numerous basic research endeavors undertaken over the last 30+ years to identify the key targets in the dysregulated inflammatory pathways and judged the level of evidence for a given target if it was generated by in vitro, in vivo or clinical experiments. MEC pathogenesis was found to be connected to cytokines characteristic for Th1, Th17 and M1 cells. In addition, we found that the inflammation created damage associated molecular patterns (DAMPs), which further promoted inflammation. Similar positive feedback loops have already been described for other Th1/Th17 driven inflammatory diseases (arthritis, Crohn’s disease or multiple sclerosis). A wide-ranging search for molecular targeted therapies (MTT) led to the discovery of over a hundred clinically approved drugs already applied in precision medicine. Based on exclusion criteria designed to enable fast translation as well as efficacy, we condensed the numerous MTTs down to 13 top drugs. The review should serve as groundwork for the primary goal, which is to provide potential pharmaceutical therapies to MEC patients for the first time in history.

Is there fungal infestation in paediatric chronic otitis media - Mucosal disease?

OBJECTIVES

To determine the prevalence of fungal infestation in paediatric chronic otitis media (COM)-mucosal disease and to study the various factors that might influence the said infestation.

METHODS

A cross-sectional study was done on the cited subject in a sample size of 66 paediatric patients [Age group: 1-18 years] suffering from active COM-mucosal disease. In all we had 75 ears from which swab samples were taken as some patients had bilateral disease. Clinical record was documented in each case. Three sample swabs were analysed for aerobic, anaerobic and fungal infection respectively from the discharging ear. Fungal infection was diagnosed by culture. The data was tabulated and statistically analysed for any correlation of fungal infestation with age, sex, background, duration of COM, previous antibiotic/steroid usage and intractable otorrhoea.

RESULTS

We recorded a prevalence of 32% for fungal colonization of COM-mucosal disease in paediatric population i.e., 24 out of 75 ears. There was no association observed between fungal infestation and specific paediatric age group, sex, background or duration of the disease. However, a distinct statistical correlation was present between fungal infestation and previous antibiotic/steroid usage and intractable otorrhoea.

CONCLUSION

Findings of this study lead us to conclude that all cases of paediatric COM-mucosal disease should be analysed for fungal colonization, especially those with intractable otorrhoea and there should be judicious use of antibiotics and steroid ear drops in COM-mucosal disease.

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.

The Role of Biofilms in Chronic Otitis Media-Active Squamosal Disease: An Evaluative Study

OBJECTIVES

To study the presence of biofilms in patients of chronic otitis media (COM)-active squamosal disease and to evaluate the microflora and clinical impact of biofilms.

METHODS

A total of 35 patients suffering from COM - active squamosal disease was studied. Cholesteatoma sample was collected at the time of mastoid surgery and the same was used to image for biofilms by scanning electron microscope. The said sample was also analyzed microbiologically.

RESULTS

Biofilms were present in 25 (72%) patients including 6 cases of fungal biofilms (24%). Biofilms were detected irrespective of the micro-organism growth. No statistically significant relationship was observed between biofilms and discharging ear and complications of COM. Though univariate analysis of our data found some correlation between duration of disease, the extent of cholesteatoma and ossicular necrosis but multivariate analysis revealed no such associations, thereby implying a doubtful association between these factors and biofilm.

CONCLUSIONS

Biofilms are an integral part of cholesteatoma ear disease and sometimes harbors fungal isolates.

Mycology of chronic suppurative otitis media-cholesteatoma disease: An evaluative study

AIMS & OBJECTIVES

To detect the prevalence of fungus in chronic suppurative otitis media-cholesteatoma disease and to evaluate its clinical significance.

STUDY DESIGN

Prospective observational study conducted in a sample size of 46 patients at a tertiary care university teaching hospital.

MATERIALS & METHODS

Forty six patients suffering from chronic suppurative otitis media-cholesteatoma disease were recruited in this prospective study. Data was duly recorded. Cholesteatoma sample was procured at the time of mastoid surgery and microbiologically analysed for fungal infestation. Clinical correlation to fungus infestation of cholesteatoma was statistically analysed.

RESULTS

Out of the recruited 46 patients, post-operatively cholesteatoma was seen in 40 cases only. Seventeen i.e. 42.5% of these cases had fungal colonization of cholesteatoma. Further a statistically significant correlation between persistent otorrhoea and fungal infestation of cholesteatoma was observed. Three cases of fungal otomastoiditis were also recorded in this study, but a statistically significant correlation between complications and fungus infestation of cholesteatoma could not be clearly established.

CONCLUSIONS

There is fungal colonization of cholesteatoma which is pathogenic and can cause persistent otorrhoea.

Bacterial Infections and Osteoclastogenesis Regulators in Men and Women with Cholesteatoma

One of the most distinct features of middle ear cholesteatoma is bone destruction. Aetiology of cholesteatoma is thought to be multifactorial. Endotoxins produced by bacteria are thought to initiate the inflammation process in the middle ear leading to cholesteatoma. There are physiological differences in bone metabolism between men and women. The aim of our study was the immunohistochemical evaluation of the contents of two key components of the OPG/RANK/RANKL triad-RANKL and OPG in cholesteatoma, to analyse if there are any differences between the sexes and to evaluate the bacteria species isolated from cholesteatoma just before surgical treatment and to evaluate their plausible influence on the expression of OPG and RANKL in cholesteatoma. Twenty-one adult patients with acquired cholesteatoma who underwent surgery were analysed. There were no statistically significant differences in the expression of both regulators of osteoclastogenesis between the sexes. In 38.1 % patients cholesteatoma was not infected, whereas in 61.9 % patients various bacterial infections or mycosis were found. The most frequently isolated species was Pseudomonas aeruginosa (14.29 % infections) followed by Staphylococcus aureus (9.52 % infections). There were no statistically significant differences in expression of both OPG and RANKL between uninfected and infected cholesteatomas.