Otomycosis in a Rural Community Attending a Tertiary Care Hospital: Assessment of Risk Factors and Identification of Fungal and Bacterial Agents

Otomycosis: The foremost aetiological agent causing otitis externa and the antifungal susceptibility pattern in North-Western Iran

BACKGROUND

Otomycosis is considered a recurring fungal ear infection. The external auditory canal provides an appropriate and optimal situation for fungal growth.

OBJECTIVES

The study aimed to identify the causative agents of otomycosis and determine corresponding antifungal drug susceptibility patterns in north-western Iran.

METHODS

From October 2020 until November 2021, 200 patients attended an otolaryngology referral centre with otitis externa, and their ear discharge and debris were examined and cultured. The identification of the fungal agents was implemented by polymerase chain reaction-restriction fragment length polymorphism and sequencing. In vitro antifungal susceptibility testing of the isolates was conducted in accordance with the CLSI broth microdilution protocols.

RESULTS

The prevalence of otomycosis was measured 50.5% (n = 101/200). The majority of patients were in their forties (n = 35, 34.6%) and female (n = 57, 56.4%), and the most prevalent symptom was otalgia (56.4%). The most underlying factor was remarked manipulation employing a cotton swab (65.3%). Regarding fungus, Aspergillus section Nigri (58.57%) was the foremost isolate, followed by Aspergillus section Flavi (19.23%) and Candida parapsilosis (14.96%). The predominance of Aspergillus isolates had minimal in vitro sensitivity to tioconazole and nystatin. Candida species represented higher geometric mean minimum inhibitory concentrations (MIC) against nystatin. The MIC of three Aspergillus species isolates shown above the epidemiologic cut-off values (ECV) against itraconazole.

CONCLUSIONS

Otomycosis incidence surpassed in comparison with the previous study as the most common cause of otitis externa. The MIC distribution of Aspergillus species isolates against triazole antifungals is close to the defined ECVs and likely outrun it over time.

In Vitro Antifungal Activity of Luliconazole, Efinaconazole, and Nine Comparators Against Aspergillus and Candida Strains Isolated from Otomycosis

Background: Aspergillus and Candida species are the most commonly identified fungal pathogens in otomycosis. However, we usually encounter some difficulties in its treatment because many patients show resistance to antifungal agents and present a high recurrence rate. Objectives: The current research was conducted to compare the in vitro activities of luliconazole (LUL), and efinaconazole (EFN) and the nine comparators on Aspergillus and Candida strains isolated from otomycosis. Methods: The in vitro activities of nine common antifungal drugs (amphotericin B (AMB), voriconazole (VRC), fluconazole (FLU), itraconazole (ITC), ketoconazole (KTO), clotrimazole (CLO), nystatin (NYS), terbinafine (TRB), and caspofungin (CAS)) and two novel new azoles (LUL and EFN) against 108 clinical isolates of Aspergillus and Candida species obtained from otomycosis were assessed according to the CLSI broth microdilution document. Results: The LUL and EFN had the geometric mean minimum inhibitory concentrations (GM MICs) of 0.098 and 0.109 μg/mL against all Aspergillus strains, respectively. Furthermore, the GM MICs of all Candida isolates for LUL, EFN, CAS, CLO, VRC, AMB, ITC, KTO, FLU, NYS, and TRB were calculated to be 0.133, 0.144, 0.194, 0.219, 0.475, 0.537, 0.655, 1.277, 4.905, 9.372, and 13.592 μg/mL, respectively. Additionally, 6 (35.29%), 2 (11.7%), and 1 (5.88%) Candida isolates were resistant to FLU, CAS, and VRC, respectively. Conclusions: As the findings indicated, LUL and EFN showed the lowest GM MIC values against the examined species. Accordingly, these novel imidazole and triazole antifungal agents can be regarded as proper candidates for the treatment of otomycosis caused by Aspergillus and Candida strains.

Clinico-Mycological Profile of Otomycosis in Chronic Suppurative Otitis Media Patients Attending a Tertiary Care Teaching Hospital

Chronic Suppurative Otitis Media (CSOM) is commonly encountered chronic inflammation of middle ear as well as the mastoid cavity due to dysfunction of Eustachian tube followed by microbial infection. Fungal infection in CSOM is now a major otolarynological problem in India not only in children but in adults too. Excessive use of steroids, antibiotics, cytotoxic chemotherapies and immunosuppressive diseases has increased the incidence of otomycosis in recent years. To define the aetiology of clinically diagnosed otomycosis. To isolate and identify fungal agents and their association with different factors(age, sex, predisposing factors). A total of 100 clinically diagnosed patients of CSOM with suspicion of otomycosis were included in the study. Patients where passing swab is difficult as with canal stenosis were excluded. Samples were taken using sterile swabs and studied for microbial profile. Male to female ratio in study was 1.6:1. The most common fungi isolated in CSOM cases was Aspergillus fumigatus followed by Aspergillus niger. Other fungus isolated were Aspergillus flavus, Penicillium species, Mucor species and Candida species. 04 samples showed mixed growth of Aspergillus species and Candida species. In our study we concluded that Aspergillus complex was most commonly isolated fungi in CSOM cases.

Molecular Identification and Antifungal Susceptibility of Yeasts and Molds Isolated from Patients with Otomycosis

Fungal otitis externa, an infection of the external auditory canal caused by molds and yeasts, accounts for approximately 10-20% of ear canal infections accompanying high recurrence. The purpose of the current study was to assess the pattern of etiological agents of otomycosis and resistance profile as well as the rate of tympanic membrane perforation. A total of 1040 patients with symptoms of fungal otitis externa, in a period of two years, were investigated. The mycological tests revealed the presence of different fungi in 237 ears (22.8%). Fungal otitis was more related to filamentous fungi of the species Aspergillus flavus (54.43%), A. tubingensis (10.97%), and A. niger (8.86%), followed by yeasts, Candida orthopsilosis (7.59%), C. albicans (6.75%), and C. parapsilosis (5.06%). Tympanic membrane perforation rate was found to be 6.75% and was more common with otomycosis caused by A. flavus, A. tubingensis and C. albicans. In antifungal susceptibility tests, all tested drugs showed generally good activity against most isolates of molds and yeasts, while tolnaftate, clotrimazole, nystatin, and terbinafine had lowest effects. We found that among Aspergillus isolates, one A. niger isolate was resistant to voriconazole, and one A. flavus isolate was resistant to amphotericin B. Furthermore, among Candida species, three isolates of C. orthopsilosis showed high MIC values to fluconazole, two C. albicans isolates were considered fluconazole resistant and one isolate of C. parapsilosis was resistant to caspofungin and 3 isolates were resistant to fluconazole. Regarding the existence of the cases with perforated tympanic membrane and emerging species causing fungal otitis in the current report, the importance of the early physical examination, precise molecular identification, and the antifungal susceptibility evaluation is highlighted.

Tympanic membrane perforation secondary to Aspergillus niger otomycosis

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Aspergillus is a fungal mold, which is ubiquitous in nature.

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Aspergillosis results in significant morbidity and mortality worldwide.

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A rare case of tympanic membrane perforation secondary to Aspergillus niger otomycosis was reported.

Aspergillus niger is one of more than 340 different species belonging to the filamentous fungal genus Aspergillus. Aspergillosis can present with a wide range of clinical syndromes, and it results in significant morbidity and mortality worldwide. Here we described a rare case of the left central tympanic membrane perforation secondary to Aspergillus niger otomycosis. The patient underwent tympanoplasty with good improvement.

Treatment of Otomycosis in Ears with Tympanic Membrane Perforation is Easier with Paper Patch

Objective

To assess the effectiveness of paper patch closure of tympanic membrane perforation in patients with otomycosis and tympanic membrane perforation.

Methods

Fifty-six otomycosis patients with central tympanic membrane perforations were included in the study. Patients were randomized into two groups as patched (PG) and non-patched (NPG) groups. In both groups, Castellani's solution was applied to the external auditory canal. In PG patients, the perforated tympanic membrane was covered with carbon paper patch soaked in Castellani's solution to reduce ear canal humidity and to prevent fungi from passing from the ear canal to the middle ear mucosa. Paper patch was not used in NPG patients.

Results

There were statistically significant differences between the two groups in terms of severity scores in the first, second, third, fourth and sixth weeks of admission (p=0.004, p=0.018, p=0.001, p=0.009, and p<0.001, respectively). Time to complete recovery was statistically shorter in PG patients (p<0.001). Disease recurrence was statistically less among PG patients compared to NPG patients (p=0.025).

Conclusion

Closing of perforation with paper patch and topical application of Castellani's solution was found to be an effective and safe method. The method eliminated otomycosis in a shorter period and reduced recurrence rate in patients with eardrum perforation.

Identification of Fungal Pathogens in Otomycosis and Their Drug Sensitivity: Our Experience

Introduction  Otomycosis is a common problem in otolaryngology practice. However, we usually encounter some difficulties in its treatment because many patients show resistance to antifungal agents, and present high recurrence rate. Objectives  To determine the fungal pathogens that cause otomycosis as well as their susceptibility to the commonly used antifungal agents. Additionally, to discover the main reasons for antifungal resistance. Methods  We conducted an experimental descriptive study on 122 patients clinically diagnosed with otomycosis from April 2016 to April 2017. Aural discharge specimens were collected for direct microscopic examination and fungal culture. In vitro antifungal susceptibility testing was performed against the commonly used antifungal drugs. We tested the isolated fungi for their enzymatic activity. Results  Positive fungal infection was found in 102 samples. The most common fungal pathogens were Aspergillus and Candida species, with Aspergillus niger being the predominant isolate (51%). The antifungal susceptibility testing showed that mold isolates had the highest sensitivity to voriconazole (93.48%), while the highest resistance was to fluconazole (100%). For yeast, the highest sensitivity was to nystatin (88.24%), followed by amphotericin B (82.35%), and the highest resistance was to terbinafine (100%), followed by Itraconazole (94.12%). Filamentous fungi expressed a high enzymatic ability, making them more virulent. Conclusion  The Aspergillus and Candida species are the most common fungal isolates in otomycosis. Voriconazole and Nystatin are the medications of choice for the treatment of otomycosis in our community. The high virulence of fungal pathogens is owed to their high enzymatic activity. Empirical use of antifungals should be discouraged.

Fungal Suppurative Otitis Media (Histopathology) Among Patients in North India

Chronic suppurative otitis media (CSOM) has a substantial worldwide prevalence and is a major cause of hearing impairment. In cases of CSOM unresponsive to local antibiotics, superimposed fungal infection should be suspected. The aim of the present study was to study the spectrum of cases with fungal otitis media. The study was conducted over a period of 12 years (2006-2017). Fifteen cases of CSOM clinically not suspected to be of fungal etiology that underwent surgery with identification of fungal organisms on histopathology were included in the study. Age of the patients ranged from 12 to 75 years (mean age: 37.1 ± 22.7 years). Of 15 cases, 9 (60.0%) were males and 6 (40.0%) were females. It was a unilateral presentation in all. The complaints observed were ear discharge in all followed by itching (86.7%), pain (46.7%), decreased hearing (26.7%) and blocking sensation (13.3%). Histomorphologic typing of fungus was possible in 13/15 patients. Isolated aspergillus was identified in eight patients while mucor alone was seen in three patients. Mixed infection with Aspergillus + Candida and Aspergillus + Mucor was seen in one patient each. Categorization of fungus could not be done in rest of the two patients due to paucity of fungal profiles. Histopathological identification of fungal organisms in otomycosis provides a quick and fairly reliable diagnosis. Culture is considered the gold standard but it may not always be available or fruitful. Less turnaround time and accurate diagnosis facilitates prompt and optimal therapy in fungal otitis media thus preventing adverse outcomes.

Otomycosis in Damascus, Syria: Etiology and clinical features

Background and Purpose:

Otomycosis is a fungal infection that frequently involves the external auditory canal. The epidemiologic data on the etiologic agents of otomycosis in Syria are very limited. In this study, we aimed to determine the fungal agents, gender distribution, and clinical presentation of otomycosis.

Materials and Methods:

Two hundred and ninety nine patients (153 [51.17%] male and 146 [48.83%] female) clinically prediagnosed as otomycosis were studied at Al-mouassat University Hospital and ENT Crescent Syrian Clinic. Clinical samples were collected from the ear discharges and cultured on Sabouraud Agar.

Results:

Otomycosis was diagnosed in 70 (23.4%) cases, with the highest prevalence in males aged 16-75 years (73.6%). The isolation rates of mold and yeast fungi were 75.7% and 24.3%, respectively. The most common presentations were otorrhea (98.66%), otalgia (18.06%), and hearing loss (6.35%). Our results showed that 64.28% of otomycosis agents were Aspergillus species. A.niger was the most common agent (45.7%), and 24.3% of the pathogens were C.albicans.

Conclusion:

Otomycosis agents most commonly belonged to the genus of Aspergillus followed by Candida, which should be seriously considered by physicians for appropriate treatment.