The investigation of bacteriology of chronic suppurative otitis media in patients attending a tertiary care hospital with special emphasis on seasonal variation

Biofilm Producing Organisms and Their Antibiotic Sensitivity in Chronic Suppurative Otitis Media: A Cross-Sectional Study

Chronic Suppurative Otitis Media (CSOM) is an inflammation of the mucoperiosteal lining of the middle ear cleft. Recently, biofilms have been discovered to play a pivotal role in the pathogenesis of CSOM. A biofilm is a bacterial aggregation that adheres to the mucosal surfaces and is connected with an extracellular matrix. Biofilms enhance antibiotic resistance, facilitate genetic alterations and amplify competence to combat host immunity. This study aims to identify the spectrum of biofilm-producers in CSOM and investigate their antibiotic sensitivity. Samples (648) were obtained from the deeper part of external auditory meatus of patients with CSOM. Pus samples were collected and processed for culture sensitivity. Biofilms detected. The findings were compiled and statistically analyzed. Out of 500 culture-positive samples, most commonly isolated bacteria was Pseudomonas (62.6%), followed by MRSA (13.8%). Biofilm-producers were 350, with 119 being strong, 167 moderate, and 64 weak. Biofilms were produced by 70% of the isolates, with Pseudomonas producing the most (74.6%), followed by MRSA. Gentamicin was the most effective antibiotic against biofilm-producers. Amoxicillin-Clavulanic Acid, Ceftriaxone, Cefuroxime, and Minocyclin were resistant. Pseudomonas had the highest sensitivity to Levofloxacin (96.6%), followed by Ceftazidime and Ciprofloxacin. Pseudomonas was resistant to Cefuroxime, Amoxicillin-Clavulanic acid and Linezolid. Multi-drug resistance has been widespread among CSOM causal species, particularly in biofilm producers. Thus, screening for biofilm formation, in addition to the standard antibiogram, must be undertaken as part of CSOM protocol. This will address the multi-drug resistance and select an appropriate treatment modality.

Impact of Intraoperative Findings on Hearing in Revision Ear Surgery

Introduction

Hearing results after chronic ear surgery encompass recurrence, localization and extent of cholesteatoma, type of surgery, ossiculoplasty methods, but rarely interpret intraoperative findings. This study aimed to analyze the impact of intraoperative findings in revision tympanomastoidectomy in predicting postoperative hearing.

Materials and Methods

This was a retrospective non-randomized cohort of 101 patients treated for recurrent chronic otitis media by tympanomastoidectomy. The patients' demographics, localizations of disease recurrence and perioperative hearing results were analyzed.

Results

Logistic regression showed that presence of tympanic perforation (p=0.036), ossicular chain damage (p=0.006), were negatively associated with improved hearing postoperatively. Attic cholesteatoma was associated with better postoperative hearing (p=0.045). Presence of tympanic perforation (p=0.050), alongside perifacial localization of imflammation (p=0.021) and ossicle destruction (p=0.013) were associated with worse postoperative hearing results. Multivariate analysis confirmed that tympanic perforation (p=0.040, F=4.401), and ossicular chain involvement (p=0.025, F=5.249), were consistent negative predictors of hearing improvement, while postoperative deterioration of hearing was associated with tympanic perforation (p=0.038, F=4.465) and facial nerve dehiscence (p=0.045, F=4.160).

Conclusions

Comparison of postoperative revision tympanomastoidectomy hearing outcomes revealed significant positive reductions in air-bone gap values, primarily at low and mid frequencies. Postoperative hearing results at high frequencies are not affected by revision surgery.

Surveillance of Antimicrobial Susceptibility Pattern of Chronic Suppurative Otitis Media in Tertiary Care Hospital of Southern Rajasthan

The main aim of this work is to identify aerobic bacteriology and antibiotic sensitivity pattern of chronic suppurative otitis media in tertiary care hospital of southern Rajasthan. Two hundred and fifty clinically diagnosed cases of chronic suppurative otitis media of all age groups and both the sexes with the ear discharged of more than 6 weeks duration formed the subject of the study group. The specific identification of bacterial pathogens is done based on microscopic morphology, staining characteristics, cultural and biochemical properties using standard laboratory procedures. Antimicrobial susceptibility of the bacterial isolates to the commonly used antibiotics according to CLSI guideline is done by Kirby-Bauer disc diffusion method. Out of 250 cases, 226 (90.4%) were found to be smear positive and culture positive, 17 (6.8%) were found smear positive and culture negative, 7 (2.8%) were smear negative and culture negative. Pseudomonas spp was found the most common organism isolated was. Out of 244 isolates, 174 (71.3%) were found to be sensitive to Amikacin. In our study, Pseudomonas spp. 98% isolates were found to be most sensitive to Meropenem and 84.2% isolates were found to be most resistance to Ceftazidime. This study is useful to prevents the administration of unwanted antibiotics and in development of empirical policy. This may be helpful to medical practitioner for the prescribing antibiotics in the treatment of CSOM.

Mapping of audiometric analysis with microbiological findings in patients with chronic suppurative otitis media (CSOM): a neglected clinical manifestation

Otitis media (OM) is an umbrella term for a number of conditions associated with middle ear inflammation. Chronic suppurative otitis media (CSOM), a type of OM, is characterized by long-term middle ear infection with perforated ear drum and otorrhea. The most common outcome associated with it is acquired hearing impairment in infected individuals which ultimately affects their cognitive and scholastic developments. Clinically, CSOM is thought to be a sequel of re-occurring episodes of Acute otitis media (AOM). Pseudomonas aeruginosa and Staphylococcus aureus are found to be the predominant pathogenic isolates in these patients. However, with the emergence of antibiotic resistance amongst these pathogens, the adequate evaluation and treatment of this condition has become more problematic. The disease has also been recognized as one of the neglected tropical clinical manifestations with high prevalence in school-age children, especially in poor or underprivileged countries. Moreover, untreated cases have further worsened the situation by contributing to various life-threatening complications. Thus, effective treatment and surgical strategies, as well as strengthening of hearing care algorithms along with the discovery of novel animal models for advanced clinical research, can jointly help to fight this disease. In this regard, mapping of the audiological analysis with microbiological findings in CSOM patients may help elucidate the frequency that favors growth of specific pathogens. Knowledge about this potential correlation can then support timely detection of the infection, which is perceived as one of the emerging approaches for its management. In addition to these strategies, creating a true sense of awareness among people can also help mitigate this pathological condition by facilitating early identification, prevention, and treatment. This review discusses the incidence, pathogenesis, investigations, complications, and available treatment modalities associated with CSOM.

Microbiological Assessment of Chronic Otitis Media: Aerobic Culture Isolates and Their Antimicrobial Susceptibility Patterns

As there are changing trends in the microbiology of chronic otitis media, this study was carried out to look for the current aerobic microbes and their antimicrobial susceptibilities in patients of chronic otitis media from north Indian region. A total of 322 patients who met the inclusion criteria were studied and aerobic ear swab culture was done under aseptic conditions. Gram staining was performed and antibiotic susceptibility testing was done using Kirby-Bauer disc diffusion method on Mueller-Hinton Agar. A total of 341 culture positive results were obtained from 322 patients. The culture results revealed 10 different aerobic microbes. Gram-positive floras were seen in 152 (44.57%), and Gram-negative in 189(55.43%) isolates. Staphylococcus aureus was the most common isolate present in 131 samples (38.41%), followed by pseudomonas aeruginosa in 101 (29.62%) and proteus in 36 (10.56%). In overall susceptibility of antibiotics against Gram-positive culture isolates, Vancomycin was most effective (97.37%). For Gram-negative microbes, Piperacillin-Tazobactum combination was most effective with overall susceptibility of 79.37% susceptibility. Microbiological assessment of Chronic Otitis Media should be carried out in an area on regular intervals because of the changing patterns of bacteriology and their antimicrobial susceptibilities.

Characterization of Ciprofloxacin Resistance Levels: Implications for Ototopical Therapy

HYPOTHESIS

Ciprofloxacin-resistant pathogens are inhibited by high concentrations of ciprofloxacin found in commercially-available ototopical solutions.

BACKGROUND

Ciprofloxacin-resistant pathogens in otitis media are currently treated with ototopical ciprofloxacin suspensions. This is done irrespective of laboratory-reported ciprofloxacin susceptibility, under the assumption that the high concentration of ciprofloxacin applied topically is sufficient to overcome antimicrobial resistance.

METHODS

We evaluated 34 ciprofloxacin-resistant isolates consisting of Staphylococcus aureus, Pseudomonas aeruginosa, Corynebacterium spp., and Turicella otitidis. Ciprofloxacin minimum inhibitory concentration (MIC) assays and clinical ototopical solution minimum bactericidal concentration (CMBC) assays were performed.

RESULTS

Amongst the ciprofloxacin-resistant isolates, ciprofloxacin MICs ranged from 8 to 256 mcg/ml (mean: 87.1 mcg/ml) and CMBCs ranged from 23.4 to 1500 mcg/ml (mean: 237.0 mcg/ml). There were no significant differences with respect to MIC in comparing P. aeruginosa versus Corynebacterium spp. (mean: 53.3 versus 55.2, p = 0.86), S. aureus versus P. aeruginosa (mean: 128.0 versus 53.3, p = 0.34), and S. aureus versus Corynebacterium spp. (mean: 128.0 versus 55.2, p = 0.09). The correlation between ciprofloxacin MIC and CMBC was poor (Pearson's r = -0.08, p = 0.75).

CONCLUSIONS

Ciprofloxacin-resistant pathogens commonly recovered from otitis media exhibit highly variable ciprofloxacin MIC and CMBC levels. Ciprofloxacin was able to inhibit growth in all isolates tested at MIC levels less than or equal to 256 mcg/ml; however, CMBC's up to 1500 mcg/ml were observed within that same group. The clinical relevance of these in vitro MICs is unclear due in part to higher bactericidal concentrations (CMBC) in several strains. Our results suggest that treatment failures may be due to a combination of factors rather than high-level resistance alone.

Treatment with a neutrophil elastase inhibitor and ofloxacin reduces P. aeruginosa burden in a mouse model of chronic suppurative otitis media

Chronic suppurative otitis media (CSOM) is a widespread, debilitating problem with poorly understood immunology. Here, we assess the host response to middle ear infection over the course of a month post-infection in a mouse model of CSOM and in human subjects with the disease. Using multiparameter flow cytometry and a binomial generalized linear machine learning model, we identified Ly6G, a surface marker of mature neutrophils, as the most informative factor of host response driving disease in the CSOM mouse model. Consistent with this, neutrophils were the most abundant cell type in infected mice and Ly6G expression tracked with the course of infection. Moreover, neutrophil-specific immunomodulatory treatment using the neutrophil elastase inhibitor GW 311616A significantly reduces bacterial burden relative to ofloxacin-only treated animals in this model. The levels of dsDNA in middle ear effusion samples are elevated in both humans and mice with CSOM and decreased during treatment, suggesting that dsDNA may serve as a molecular biomarker of treatment response. Together these data strongly implicate neutrophils in the ineffective immune response to P. aeruginosa infection in CSOM and suggest that immunomodulatory strategies may benefit drug-tolerant infections for chronic biofilm-mediated disease.

Microbiology of chronic suppurative otitis media at Queen Elizabeth Central Hospital, Blantyre, Malawi: A cross-sectional descriptive study

BACKGROUND

Chronic suppurative otitis media (CSOM) is still a significant health problem in developing countries. Therefore, it was pertinent to determine the local Malawian microbiology in order to guide adequate treatment, avoid complications, and provide records for future reference.

AIM

The study sought to determine the CSOM-causing microorganisms at Queen Elizabeth Central Hospital in Blantyre, Malawi, and establish their relationship signs and symptoms, and with the demographic pattern of the study.

METHODS

This was a hospital-based cross-sectional descriptive study carried out at the ENT outpatient clinic and the Microbiology Department of Queen Elizabeth Central Hospital.The sample comprised 104 patients with unilateral or bilateral active CSOM, who met the inclusion criteria. All patients were evaluated through a detailed history and clinical examination. Pus samples from draining ears were collected by aspiration with a sterile pipette. The specimens were immediately sent for microbiological analysis. Data were analyzed using SPSS.version 20.

RESULTS

The study found that Proteus mirabilis, Pseudomonas aeruginosa, and Staphylococcus aureus were the most prevalent aerobic bacteria, while Bacteroides spp. and Peptostreptococcus spp. were the commonest anaerobic bacteria causing CSOM. These CSOM-causing microorganisms were predominant among males aged 18 years and below. Some CSOM-causing microorganisms were-significantly more so than the others-characteristically associated with each of the following clinical features: quantity of pus drainage, mode of onset, otalgia, hearing loss, location of tympanic membrane perforation, and mucosal appearance.

Observations on the current bacteriological profile of chronic suppurative otitis media in South eastern Nigeria

Background:

Chronic suppurative otitis media (CSOM) is a disease well-known for its recurrence and persistence despite treatment. The situation is compounded by the increasing resistance to antimicrobial agents by bacteria these days.

Aim:

This study was carried out to examine the current local bacteriological profile of CSOM and to compare the profile of either ear in bilaterally discharging ears.

Materials and Methods:

We carried out a retrospective analysis of ear swab cultures from 133 unilateral and 73 bilateral consecutive tubotympanic CSOM cases seen at the Ear-Nose-Throat clinics of a referral health institution during a 4 year period ending 2013. Sensitivities to eight locally available antibiotics were analyzed. Aerobic bacterial isolates were analyzed separately for the unilateral and bilateral cases. Comparison was made between the ears in the bilateral cases.

Results:

We analyzed 279 ear swab culture results from 206 patients with age ranging from 5 months to 86 years and a mean of 21.3 (19.5) years. Pseudomonas aeruginosa was the most common isolated bacteria (44% [109/250]) followed by Staphylococcus aureus (17% [42/250]), and Proteus Mirabilis (15% [38/250]). The most and least sensitive bacteria were Klebsiella Spp and Escherichia Coli, respectively. The most effective antibiotics were gentamicin and ciprofloxacin. The two ears differ significantly in the rates of isolation of S. aureus and E. coli (P = 0.01 and P = 0.04, respectively).

Conclusion:

Pseudomonas is the most common bacteria involved in CSOM in this part of the country. Ciprofloxacin as ear drops is recommended as first-line drug in the management of active CSOM as it is cheap, less ototoxic, and locally available. Separate ear swab culture should be obtained in bilateral CSOM.

Microbiology of chronic suppurative otitis media in a tertiary care setup of uttarakhand state, India

Background:

Chronic suppurative otitis media (CSOM) is a notorious infection and a major health problem in developing countries causing serious local damage and threatening complications. Early and effective treatment based on the knowledge of causative micro-organisms and their antimicrobial sensitivity ensures prompt clinical recovery and possible complications can thus be avoided.

Aims:

The aim of this study was to isolate the organisms associated with CSOM and to detect the antibiogram of the aerobic isolates.

Materials and Methods:

A total of 204 patients clinically diagnosed of CSOM were enrolled in the study and the samples were obtained from each patient using sterile cotton swabs and cultured for microbial flora. Drug susceptibility testing for aerobic isolates was conducted using Kirby-Bauer disc diffusion method.

Results:

The most common causative organisms isolated were Staphylococcus aureus (48.69%) and Pseudomonas aeruginosa (19.89%) amongst the 191 aerobic isolates. Anaerobes accounted for 29.41% of the isolates while 12.25% were fungi. Antimicrobial profile of aerobic isolates revealed maximum sensitivity to amikacin (95.5%), ceftriaxone (83.4%) and gentamicin (82.7%).

Conclusion:

Knowing the etiological agents of CSOM and their antimicrobial susceptibility is of essential importance for an efficient treatment, prevention of both complications and development of antibiotic resistance and finally, the reduction of the treatment costs.

Chronic suppurative otitis media: optimizing initial antibiotic therapy in a tertiary care setup

A prospective study was done to determine the clinico-microbiological profile and the antibiogram of patients with chronic suppurative otitis media. Ninety-four patients presenting with tympanic perforation and ear discharge of more than 3 months were studied. Middle ear swabs obtained aseptically were processed for culture and the isolates identified by standard procedures. Antimicrobial susceptibility testing of the aerobic bacterial isolates was performed by disc diffusion method according to clinical laboratory standards institute guidelines. Patients in the age group of 21-30 years were more commonly affected (22.3%). Male:Female ratio was 2:1.4. Of the 94 patients, 64 (68.1%) had tubo-tympanic disease and rest 30 (31.9%) presented with attico-antral disease. Monomicrobial flora was seen in 55 (58.5%) samples, 28 (29.8%) yielded polymicrobial growth and 11 (11.7%) samples were sterile. A total of 115 microbial isolates (86 aerobic bacteria, 18 anaerobic bacteria and 11 fungi) were obtained. Pseudomonas aeruginosa (32.2%) was the most common isolate followed by Staphylococcus aureus (17.4%). Amongst anaerobes, gram positive cocci were more commonly isolated (38.9%). Aspergillus spp. (72.7%) were the most common fungus isolated. Most of the Pseudomonas aeruginosa isolates (25, 67.6%) were susceptible to all the antibiotics. Among the commonly used topical agents in the treatment of CSOM, tobramycin was the most effective (83.8%), followed by gentamicin (78.1%), ciprofloxacin (75.6%) and neomycin (3.5%). Periodic monitoring of the microbiological profile along with their sensitivity pattern is essential for formulating an effective antibiotic policy for CSOM.

[Correlation between histomorphometric changes and the type of aerobic bacteria isolated in chronic suppurative otitis media]

BACKGROUND/AIM

Bacterial flora is a very important factor in pathogenesis of chronic suppurative otitis media (CSOM) and significantly influences the type and intensity of osteolytic process. There are few histomorphometric investigations of middle ear mucosa in chronic otitis. The aim of this study was to identify aerobic bacteria responsible for chronic suppurative otitis media as well as their association with histomorphometric changes of middle ear mucosa.

METHODS

A prospective study that comprised 153 patients treated in the Clinc for Ear, Thorat and Nose Diseases, Nis, was conducted. Bacteriologic analysis of diseased ear secretion was carried out in all patients. Intraoperatively removed granulation tissue was used for histomorphometry. The analysed parameters were: the number of inflammatory cells, as well as vascularization and vasodilatation.

RESULTS

The most frequently isolated aerobic bacteria from chronic suppurative otitis media were Staphylococcus aureus (29.020/0), Pseudomonas aeruginosa (29.02%) and Proteus spp. (21.76%). There was no correlation between the type of pathologic process and the type of bacteria. The number of inflammatory cells in the granulation tissue in pure cultures of Staphylococcus aureus was 1,597.33 +/- 549.45 and in Pseudomonas aurzginosa cultures was 2639 +/- 648.

CONCLUSION

This study showed that there is a statistically significant correlation between the number of inflammatory cells in the granulation tissue and the type of aerobic bacteria we isolated. The intensity of the infection in chronic suppurative otitis media depends on the type of the isolated bacteria, which emphasizes the importance of adequate preoperative antimicrobial therapy.