Etiological agents of otomycosis in Nigeria

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.

Otomycosis in Africa: Epidemiology, diagnosis and treatment

This review sets out to highlighted knowledge gaps regarding the epidemiological, diagnostic (clinical and laboratory) and therapeutic aspects of otomycosis in Africa. A computerized literature search for otomycosis related articles were performed using MEDLINE. The search encompassed articles published in early January 1980 to May 2019 yielded 220 articles. Electronic search on PubMed was performed with the specific keywords. This review shows the higher prevalence rates of otomycosis in Africa. These prevalences varies from one country to the other and also from one population to another within the same country. The main symptoms are otalgia, otorrhea, hearing loss, aural fullness, pruritus, and tinnitus. Otomycosis is due to several predisposing factors, however, use of topical antibiotic/steroid eardrops, trauma to the external ear canal or instrumentation of the ear, being exposed to hot humid atmospheres, and close contact with water are the common risk factors. Aspergillus species are the most commonly identified organisms compared with Candida species. Worldwide, A. niger and C. albicans are the most commonly described agents of otomycosis in Africa. The Laboratory diagnosis of otomycosis is usually confirmed by mycologic tests relied on a set of evidences. Further conventional methods such as Chromagar Candida System, latex agglutination test, Biochemical tests (Api 20C AuxTM and auxanogram), phenotypical tests (Germ-tube and chlamydosporulation), and rRNA gene sequencing (PCR) are performed to improve diagnosis and the management of the disease. Adequate treatment of otomycosis includes microscopic suction clearance of fungal mass, discontinuation of topical antibiotics and treatment with antifungal eardrops for three weeks.

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

INTRODUCTION

Otomycosis is one of the frequently encountered fungal infections of external auditory canal, commonly seen in tropical and subtropical regions of the world. Various host (local, systemic) and environmental factors can predispose a person to otomycosis. Although clinical presentations along with otoscopic findings of the patients are well suggestive of fungal infection, proper identification of causative agents is mandatory in order to prevent recurrences and complications.

AIM

To define the aetiology of clinically diagnosed otomycosis in rural population, to derive association of risk factors with otomycosis, to isolate and identify fungal and bacterial agents and to analyze the association between them.

MATERIALS AND METHODS

A prospective study was conducted in the Department of Microbiology and Department of Ear, Nose and Throat (ENT), SGT hospital over eight months period. A total of 350 consecutive patients of more than five years of age with clinical diagnosis of otomycosis were included in the study. Demographic profile, predisposing factors, presenting complaints and clinical findings of clinically diagnosed patients were evaluated and analyzed. Samples were collected, transported and evaluated by both direct examination and culture method for bacteriological and mycological examination.

RESULTS

Male to female ratio in study participants was 1.3:1. Mycological examination yielded 346 fungal isolates in 310 samples from a total of 350 clinically diagnosed cases of otomycosis. Self cleaning, instillation of mustard oil and use of ear drops appeared to be common predisposing factors in otomycosis. Significant association was observed between these practices and otomycosis. Aspergillus species was the predominant fungi followed by Candida spp., Penicillium, Mucor and Trichophyton mentagrophyte. 11% of the cases were found to have mixed fungal and bacterial infections.

CONCLUSION

The present study highlights the highest isolation of Aspergillus complex in cases of clinically diagnosed otomycosis in a rural community with higher practice of self cleaning and using home remedies and eardrops to get relief from sensation of blocked ear and itching.

Comparative analysis of pathogenic organisms in cockroaches from different community settings in Edo State, Nigeria

Cockroaches are abundant in Nigeria and are seen to harbour an array of pathogens. Environmental and sanitary conditions associated with demographic/socio-economic settings of an area could contribute to the prevalence of disease pathogens in cockroaches. A total of 246 cockroaches (Periplaneta americana) in urban (Benin, n=91), semi-urban (Ekpoma, n=75) and rural (Emuhi, n=70) settings in Edo State, Nigeria were collected within and around households. The external body surfaces and alimentary canal of these cockroaches were screened for bacterial, fungal, and parasitological infections. Bacillus sp. and Escherichia coli were the most common bacteria in cockroaches. However, Enterococcus faecalis could not be isolated in cockroaches trapped from Ekpoma and Emuhi. Aspergillus niger was the most prevalent fungus in Benin and Ekpoma, while Mucor sp. was predominant in Emuhi. Parasitological investigations revealed the preponderance of Ascaris lumbricoides in Benin and Emuhi, while Trichuris trichura was the most predominant in Ekpoma. The prevalence and burden of infection in cockroaches is likely to be a reflection of the sanitary conditions of these areas. Also, cockroaches in these areas making incursions in homes may increase the risk of human infections with these disease agents.

Prevalence of otomycosis in Khouzestan Province, south-west Iran

BACKGROUND

This study aimed to investigate the prevalence of otomycosis and aetiological agents in Khouzestan province, south-west Iran.

METHODS

This cross-sectional study examined and cultured 881 swabs from suspected external otitis cases, collected from throughout Khouzestan province. Fungal agents were identified by slide culture and complementary tests when necessary.

RESULTS

The mean patient age was 37 years. The 20-39 year age group had the highest prevalence of otomycosis: 293 cases, comprising 162 (55.3 per cent) women and 131 (44.7 per cent) men. The seasonal distribution of cases was: summer, 44.7 per cent; autumn, 28.7 per cent; winter, 14.7 per cent; and spring, 11.9 per cent. The fungal agents isolated were Aspergillus niger (67.2 per cent), Aspergillus flavus (13 per cent), Candida albicans (11.6 per cent), Aspergillus fumigatus (6.2 per cent) and penicillium species (2 per cent).

CONCLUSION

Fungal otomycosis is still one of the most important external ear diseases. In this study in south-west Iran, Aspergillus niger was the predominant aetiological agent. However, clinicians should be cautious of candidal otomycosis, which has a lower rate of incidence but is more prevalent among 20-39 year olds.

Etiologic agents of otitis media in Benin city, Nigeria

Background:

Otitis Media continues to be a major presentation in the ear, nose and throat clinic.

Aim:

This study aimed to isolate, characterize and identify the bacteriological and mycological etiologic agents of otitis media in Benin city.

Patients and Methods:

Ear discharge from 569 (299 males and 270 females) patients diagnosed clinically of otitis media between August 2009 and August 2010 were processed to recover the bacterial and fungal etiologic agents. Susceptibility test was performed on all bacterial isolate.

Result:

Pseudomonas aeruginosa (28.3%) was the predominant bacteria isolate causing otitis media followed by Staphylococcus aureus (21.0%), Klebsiella sp (8.9%), Proteus sp (8.2%), Alkaligenes spp (4.3%), Streptococcus pneumoniae (3.9%), Escherichia coli (3.0%) and Citrobacter freundi (1.7%). Fungi isolated were Aspergillus niger (9.2%), Candida albicans (5.4%), Candida tropicalis (3.0%), Aspergillus flavus (2.1%) and Candida parasilopsis (1.5%). 413 had a single organism isolated from the middle ear culture while twenty (3.51%) patients had mixed organisms isolated. Infection was highest among 0 - 5 years, and lowest among aged 18 - 23. All bacterial isolates were poorly susceptible to the antibacterial agents.

Conclusion:

The study uncovers a high frequency of bacteria associated otitis media with the finding of fungi too as a significant etiologic agent.

Otomycosis in western Nigeria

Otomycosis is a recognized clinical entity in the tropical regions of the world. However, there is scanty information on this disease in some parts of Sub-Saharan Africa. The aim of this study was to determine the prevalence and pattern of etiological agents of otomycosis in western Nigeria. Medical records of patients with otomycosis seen in the Otorhinolaryngology Department of the University College Hospital, Ibadan from 1996-2005 were reviewed for all essential clinical data. Of the 5784 patients with ear diseases, 378 (6.54%) had otomycosis which consisted of 145 (38.36%) males and 233 (61.64%) females. Seventeen patients (4.50%) had recurrence within six months of treatment, 4 (1.06%) had poorly controlled plasma glucose. A significant number of our patients, 52 (13.76%), had prior topical aural antibiotic treatment following misdiagnosis. The predominant etiological agents in our series were Aspergillus niger (48.35%) and Aspergillus fumigatus (33.96%).

Scedosporium apiospermum: changing clinical spectrum of a therapy-refractory opportunist*

Current knowledge on the opportunist Scedosporium apiospermum (teleomorph: Pseudallescheria boydii), generated over a period of more than 120 years, is reviewed. The natural environmental habitat of the fungus is unknown; nutrient-rich, brackish waters like river estuaria have been suggested. The fungus is strongly promoted by agricultural and particularly by industrial pollution.

In vitro activity of terbinafine and itraconazole against Aspergillus species isolated from otomycosis

The minimum inhibitory concentrations (MIC, microg ml-1) of itraconazole and terbinafine against overall 34 Aspergillus isolates from the external ear canals with otomycosis have been determined with M38-P microdilution method suggested by National Committee for Clinical Laboratory Standards (NCCLS). MIC intervals in 48 h determined by taking MIC-2 value of itraconazole (the lowest drug concentration causing 50% inhibition of visible fungal growth) and MIC-0 value of terbinafine (the lowest drug concentration causing 100% inhibition of visible fungal growth) as a basis have been found as follows: 0.125-1 and 0.06-0.5 microg ml-1 for A. niger (22 strains), 0.06-0.25 and 0.06-0.125 microg ml-1 for A. flavus (10 strains), 0.125 and 0.125-0.5 microg ml-1 for A. terreus (two strains). It has been observed that both of the antifungal agents showed an in vitro activity against all Aspergillus species tested.

Randomized prospective comparative study: short-term treatment with ciclopiroxolamine (cream and solution) versus boric acid in the treatment of otomycosis

Sixty-four patients with symptomatic otomycosis (80 infected ears) confirmed by direct microscopy and culture were randomly treated for I week with ciclopiroxolamine cream 11% (group A, 20 infected ears, 17 patients), ciclopiroxolamine solution 1% (group B, 20 infected ears, 17 patients) and boric acid (group C, 40 infected ears, 30 patients) and daily mechanical suction aspiration of the debris. An attempt was made to match 11 clinical parameters with both the mycological and bacteriological findings. There was no significant association between the fungal species cultured and the clinical parameters did not vary with the presence or absence of different bacteria; pus was never present in fungal otitis externa (Fisher's test, P < 0.001). Before therapy, a significant number of ears had completely sterile bacterial cultures (p < 0.01, chi2 test); saprophytic Gram-positive bacteria increased after treatment, whilst Gram-negative bacteria, Pseudomonas aeruginosa and Proteus species, decreased after treatment. Clinical total cure rates 3 days after the end of therapy ranged from 50% in group A, 25% in group B to 22.5% in group C. Mycological cure rates were 80% (group A), 95% (group B) and 72.5% (group C). Two weeks after the end of therapy the clinical cure rates were 60% (group A), 65% (group B) and 80% (group C) and the mycological cure rates was 65% for group A and 75% for both group B and C. Eleven patients relapsed with otitis externa: four (20%) in groups A and C and three (15%) in group B. In four cases the infection was due to bacteria and the remaining seven were due to fungi. Six sites relapsed with the same fungal species as that isolated at the start of the study. In this short-term assessment the relapse rate was not significantly associated with predisposing conditions. The tolerance was excellent in group A. Four patients (20%) in group B had mild (two patients) or moderate (two patients) burning and itching with each application. Twelve patients (30%) in group C had severe stinging and five of these patients who had perforated tympanic membranes also experienced pain. In terms of clinical and mycological effectiveness, there were no significant differences between the three treatment groups, although group A (ciclopiroxolamine cream 1%) and B (ciclopiroxolamine solution 1%) both showed significantly better tolerance (Fisher's test, P < 0.05) when compared with boric acid (group C).

Otomycosis in Nigeria: treatment with mercurochrome

Seventy-two mycologically proven cases of otomycosis (38 males, 34 females) aged 8-80 years were investigated. Aspergillus niger was the commonest aetiological agent (43.1%) followed by Candida spp. (22.2%), A. flavus (19.4%) and A. fumigatus (15.3%). Three topical drugs, namely mercurochrome, clotrimazole and locacorten-vioform, were evaluated for otomycosis therapy in separate groups of 24 patients each. Mercurochrome was found to be the most efficacious in terms of healing, relief from symptoms of the disease and production of negative fungal cultures. Mercurochrome is recommended as a safe and economical drug for the topical treatment of otomycosis in developing countries like Nigeria.

Prevalence of otomycosis in malnourished children in Edo State, Nigeria

Out of the total number at 200 suspected cases of otomycoses consisting of 40 malnourished and 160 apparently healthy children examined in this study between the months of July and August in Edo State, 64 Cases (32%) were identified to be of fungal aetiology on the basis of positive culture and careful microscopic examination. The state at protein energy malnourishment was deterwined using physicians' comments in their case files. The fungal agents isolated were Aspergillus niger 28 (43.8%); A. fumigatus 4 (25%); Fusarium solari 4 (6.3%); Candida albicans 8 (12.5%); and Hendersonula teruloidea types torn B 5 (6.3%). Of these isolates, A. niger having an solation rate of (43.8%) was found to be the most predominant fungal species associated with otomycosis.

New and emerging yeast pathogens

The most common yeast species that act as agents of human disease are Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Cryptococcus neoformans. The incidence of infections by other yeasts has increased during the past decade. The most evident emerging pathogens are Malassezia furfur, Trichosporon beigelii, Rhodotorula species, Hansenula anomala, Candida lusitaniae, and Candida krusei. Organisms once considered environmental contaminants or only industrially important, such as Candida utilis and Candida lipolytica, have now been implicated as agents of fungemia, onychomycosis, and systemic disease. The unusual yeasts primarily infect immunocompromised patients, newborns, and the elderly. The role of central venous catheter removal and antifungal therapy in patient management is controversial. The antibiograms of the unusual yeasts range from resistant to the most recent azoles and amphotericin B to highly susceptible to all antifungal agents. Current routine methods for yeast identification may be insufficient to identify the unusual yeasts within 2 days after isolation. The recognition of unusual yeasts as agents of sometimes life-threatening infection and their unpredictable antifungal susceptibilities increase the burden on the clinical mycology laboratory to pursue complete species identification and MIC determinations. Given the current and evolving medical practices for management of seriously ill patients, further evaluations of the clinically important data about these yeasts are needed.

Ecology and physiology of the emerging opportunistic fungi Pseudallescheria boydii and Scedosporium prolificans

Nutritionally physiological patterns of Pseudallescheria boydii (Microascaceae) and the related species Scedosporium prolificans were established. Differences between the two species were found in assimilation of sucrose, ribitol, xylitol and L-arabinitol. In contrast, no physiological distinction could be made between the three intraspecific variants of P. boydii which have been recognized on the basis of nDNA/DNA homology data and of morphological and clinical differences. Some potential virulence factors were studied in the fungi mentioned above and in some related anamorphs. All species were capable of anaerobic growth, but differed in their temperature relations.