The changes of MRSA infections in chronic suppurative otitis media

Different Bacteria and their Antibiotic Sensitivity Patterns in Patients of Chronic Otitis Media-Active Mucosal Disease at a Secondary Care Centre in Delhi

Chronic Otitis Media is characterized by distinct bacteriology compared with Acute Otitis Media, with COM being highly likely to harbor multiple bacteria of anaerobic and aerobic types of organisms (Cameron and Hussam K. El-Kashlan, xxx). In some patients, chronic infection with otorrhea will persist despite aggressive medical therapy. With the large number of cases of COM which presents to Sanjay Gandhi Memorial Hospital, and a majority being resistant to the common medications, we decided to undertake this study to have a better understanding of the bacterial epidemiology, the resistance, and what antibiotic to use in such cases. To determine the prevalence of different bacteriological agents and their antibiotic sensitivity pattern in patients of Chronic Otitis Media-Active Mucosal Disease presenting to ENT OPD at Sanjay Gandhi Memorial Hospital, Mangolpuri, Delhi. An observational cross-sectional study of 200 patients. After an initial examination, two sterile cotton swab sticks were introduced to collect pus samples from the medial part of the external auditory canal. The swabs were sent to the microbiology lab for Gram Staining, Culture, and Biochemical Tests, for identification of the different bacteriological agents and their antibiotic sensitivity patterns. Most common organism seen was Pseudomonas aeruginosa, followed by Staphylococcus aureus, Klebsiella pneumoniae, Proteus mirabilis, mixed bacterial growth, and Candida spp. If regular monitoring of bacteriological profile is done in each hospital, this will help us to choose the antibiotics in a better manner and hence prevent the appearance of newer resistant strains.

Otopathogenic Staphylococcus aureus Invades Human Middle Ear Epithelial Cells Primarily through Cholesterol Dependent Pathway

Chronic suppurative otitis media (CSOM) is one of the most common infectious diseases of the middle ear especially affecting children, leading to delay in language development and communication. Although Staphylococcus aureus is the most common pathogen associated with CSOM, its interaction with middle ear epithelial cells is not well known. In the present study, we observed that otopathogenic S. aureus has the ability to invade human middle ear epithelial cells (HMEECs) in a dose and time dependent manner. Scanning electron microscopy demonstrated time dependent increase in the number of S. aureus on the surface of HMEECs. We observed that otopathogenic S. aureus primarily employs a cholesterol dependent pathway to colonize HMEECs. In agreement with these findings, confocal microscopy showed that S. aureus colocalized with lipid rafts in HMEECs. The results of the present study provide new insights into the pathogenesis of S. aureus induced CSOM. The availability of in vitro cell culture model will pave the way to develop novel effective treatment modalities for CSOM beyond antibiotic therapy.

Prevalence and etiological agents for chronic suppurative otitis media in a tertiary hospital in Tanzania

OBJECTIVE

Chronic suppurative otitis media is among the most common otological condition reported in otorhinolaryngology practice commonly attributing to preventable hearing loss. The aim of this study was to determine the prevalence and etiological agents for chronic suppurative otitis media in our department.

RESULTS

A total of 5591 patients were recruited in this study and only 79 (1.4%) had chronic suppurative otitis media. A male preponderance 43 (54.4%) was noted in this study and the left ear (58.2%) was more commonly affected compared to the right ear. Central perforation was the commonest pattern of presentation and was reported in 53% of cases though none had attic perforation. Of the 81 processed ear swabs, microbial growth was seen in majority 80 (98.8%) whilst one sample showed no microbial growth whereas 52.5% had polymicrobial growth. Among the isolates, most were gram negative species accounting for 59.7% while gram positive bacteria accounted for 25.6% and fungi accounted for 14.7%. Most of these isolates were facultative anaerobes. Klebsiella pneumoniae (20.2%) was the commonest isolates while Escherichia coli and Pseudomonas aeruginosa were equally least isolated (10.9%). Tested isolates were most sensitive to Ciprofloxacin, Gentamycin, Ceftriaxone and Amikacin and least sensitive to Amoxicillin/clavulanic acid and Ampicillin.

Differences in Antibiotic Resistance of MRSA Infections in Patients with Various Types of Otitis Media

OBJECTIVES

We investigated the epidemiological and antibiotic resistance differences in methicillin-resistant Staphylococcus aureus (MRSA) infections in patients with otitis media with effusion (OME), acute otitis media (AOM), chronic suppurative otitis media (CSOM), and chronic cholesteatomatous otitis media (CCOM).

MATERIALS AND METHODS

We conducted a retrospective study of patients with newly identified MRSA infections from January 2009 through January 2017. Overall, 3,522 patients from 10 tertiary referral hospitals were included in the study. An antibiotic sensitivity test was performed for each isolate.

RESULTS

MRSA infections in patients with CSOM and CCOM were more resistant to ciprofloxacin, clindamycin, erythromycin, gentamicin, levofloxacin, and tetracycline. Patients showed good susceptibility to rifampicin, trimethoprim/sulfamethoxazole (TMP/SMX), and vancomycin.

CONCLUSION

MRSA infections in various otitis media cases showed different resistance patterns. MRSA infections in patients with COM and CCOM were more resistant to antibiotics than those in patients with OME and AOM.

Chronic Ear Disease

Chronic ear disease is composed of a spectrum of otologic disorders intrinsically tied to Eustachian tube dysfunction. Presentation can range from asymptomatic findings on physical examination to critically ill patients with intracranial complications. Internists represent the first line in diagnosis of these conditions, making awareness of the common signs and symptoms essential. With surgical management often required, partnership between internal medicine and otolaryngology is fundamental in the management of patients with chronic ear disease.

Ototoxic effect of daptomycin applied to the guinea pig middle ear

CONCLUSION

Daptomycin applied topically at a concentration of 50 mg/ml caused mild but statistically significant hearing impairment. Outer hair cells were not damaged by daptomycin. Great care must be taken when there is a chance that daptomycin can reach the middle ear.

OBJECTIVE

Ototopic antibiotic eardrops are frequently used to treat external and middle ear infections. Daptomycin is a new anti-methicillin-resistant Staphylococccus aureus (MRSA) drug with unknown ototoxicity. The current study examined the ototoxic effect of daptomycin in topical applications to guinea pig ears.

METHODS

Twenty-three male Hartley guinea pigs (weight, 250-640 g) were divided into three groups receiving daptomycin (50 mg/ml), gentamicin (50 mg/ml, positive control), or saline solution (negative control). After insertion of a pressure-equalizing tube, pretreatment auditory brainstem responses (ABRs) were obtained. Topical solutions of 0.1 ml were applied through the tube into the middle ear twice a day for 7 days. Post-treatment ABRs were obtained 7 days after the last treatment. Hair cell loss was investigated with whole-mount cochlear surface preparations.

RESULTS

The saline-treated (negative control) group showed no deterioration of ABR threshold. The daptomycin-treated group showed mild deterioration and the gentamicin-treated group showed severe deterioration in ABR threshold. Hair cells were preserved in the daptomycin- and saline-treated groups but severely damaged in the gentamicin group.

Panel 7: Treatment and comparative effectiveness research

BACKGROUND AND OBJECTIVES

Otitis media (OM) is one of the most common reasons for antibiotic treatment in children. Controversies regarding antibiotic treatment for OM have accumulated in the past decade, and there seem to be more dilemmas than certainties. The objectives of this article are to provide the state-of-the art review on achievements in treatment of all different stages of OM, including acute otitis media (AOM), otitis media with effusion (OME), and chronic suppurative otitis media, and to outline the future research areas.

DATA SOURCES

PubMed, Ovid Medline, the Cochrane Database, and Clinical Evidence (BMJ Publishing).

REVIEW METHODS

All types of articles related to OM treatment published in English between January 2007 and June 2011 were identified. A total of 286 articles related to OM treatment were reviewed by the panel members; 114 relevant quality articles were identified and summarized.

RESULTS

New evidence emerged on beneficial results of antibiotic treatment, compared with observation of AOM in young children who were diagnosed based on stringent criteria. In OME, the main results were related to a nonsignificant benefit of adenoidectomy versus tympanostomy tube placement alone in the treatment of chronic OME in younger children. Other modalities of OM treatment were studied and described herein.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

Significant progress has been made in advancing the knowledge on the treatment of OM. Areas of potential future research have been identified and outlined.

Otitis media

Otitis media represents a broad spectrum of disease, which include acute otitis media and otitis media with effusion. As immunization with the pneumococcal conjugate vaccine has become more widespread, the microbiological landscape of otitis media has changed, which affects the treatment options facing clinicians worldwide. This review discusses the diagnosis and medical management of acute and chronic suppurative otitis media, the changes noted over the past decade, and briefly expounds on the surgical management of their severe complications.

Emerging dilemmas with methicillin-resistant Staphylococcus aureus infections in children

PURPOSE OF REVIEW

There has been an increase in the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections in recent years. This article reviews the literature on three manifestations of MRSA infections in the head and neck of children: sinonasal infections, otologic infections, and neck abscesses.

RECENT FINDINGS

Historically nosocomial in origin, MRSA infections more recently are found to occur in otherwise healthy patients with no obvious risk factors. This community-acquired MRSA is known to be responsible for cutaneous abscesses in various regions of the body. Nasal carriage in healthy children is thought to account for increasing incidence of infections involving the respiratory tract as well as deep-space neck infections. Although these community-acquired strains of MRSA often retain susceptibility to nonbeta lactam antibiotics, there are reports of clindamycin resistance.

SUMMARY

There is an increase in incidence of MRSA among infections involving the head and neck in children. Vigilant monitoring of antibiotic susceptibilities is warranted as well as judicious use of culture-directed antibiotic agents in their treatment. Topical therapy may play an important role in treatment of infections involving the sinonasal tract and ear.

MRSA otorrhea: A case series and review of the literature

Methicillin-resistant Staphylococcus aureus (MRSA) has become an increasingly common cause of difficult-to-treat head and neck infections. We report a retrospective analysis of 3 cases of MRSA otorrhea treated in our clinic between 2007 and 2009. Culture analysis of otorrhea isolates revealed MRSA infections with identical drug sensitivities. Treatment success was achieved using combinations of linezolid with gentamicin ear drops for 3 to 4 weeks or trimethoprim/sulfamethoxazole (TMP/SMX) with gentamicin drops for 6 weeks. This study illustrates the importance of determining individual drug sensitivities for optimal treatment and maintaining current knowledge of the local MRSA strains. Empiric combination therapy of TMP/SMX with gentamicin is an effective first-line treatment for MRSA otorrhea. Regional differences in clindamycin sensitivities warrant clinical discretion. Fluoroquinolones should be avoided because of high rates of resistance unless culture sensitivity determines that they are appropriate. First-line agents for severe infections include combination therapy with vancomycin or linezolid.

Otolaryngologic community-acquired MRSA infections in a suburban private practice

A retrospective review was conducted of all cases of head and neck community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections seen in the senior author's suburban private practice during a 12-month period. An office and hospital chart review was performed for all patients identified with culture-positive CA-MRSA infections. Several parameters were evaluated, including site of infection, prior therapy, imaging, comorbid disease, culture and sensitivities, surgical and medical management, and long-term results. Of the 10 patients identified, 3 had infections of nasal soft tissues, 3 had infections of the lips, 2 had infections of the paranasal sinus, 1 had an infection of the chin, and 1 had a diffuse, hemifacial infection. All patients were managed successfully with a combination of surgical drainage, wound care, and antibiotics. CA-MRSA is a burgeoning problem in otolaryngology. Appropriate management-including early recognition, appropriate empirical therapy, prompt and thorough surgical drainage with culture and sensitivities, correct antibiotic choice, and meticulous postoperative care-appears to offer excellent results.

Auditory Function After Application of Ototopical Vancomycin and Mupirocin Solutions in a Murine Model

Objective. To determine whether mupirocin (440 µg/mL) and vancomycin otic drops (25 mg/mL) show evidence of ototoxicity in CBA/J mice immediately following a 7-day course of daily intratympanic (IT) injections and 1 month following treatment.

Study Design. Nonrandomized controlled trial.

Setting. Academic hospital laboratory.

Subjects. Twenty CBA/J mice.

Results. Mean auditory brainstem response (ABR) thresholds increased in all drug- and saline-treated ears immediately after 7 days of IT injections but returned to baseline for most stimulus frequencies by 30 days later. This finding appeared to be correlated with the presence and subsequent resolution of tympanic membrane (TM) perforations and granulation tissue at the injection sites. Mupirocin-treated ears showed no significant difference in ABR thresholds compared to saline-treated ears. No significant differences were noted between vancomycin- and saline-treated ears, but there was a significant interaction between testing day and stimulus frequency ( P < .001). Further analysis revealed that ABR thresholds at 32 kHz remained significantly elevated in vancomycin-treated mice despite the resolution of TM perforations and granulation tissue 30 days after completion of IT injections (95% confidence interval, −13.5 to −5.5, P < .01).

Conclusion. Although IT application of mupirocin solution (440 µg/mL) caused no significant change in the ABR thresholds in a murine model, vancomycin solution (25 mg/mL) resulted in high-frequency threshold elevations in both the ear directly injected and the contralateral ear. Mupirocin solution may be beneficial in managing otitis externa and media caused by resistant pathogens. Further studies of ototopical vancomycin are needed to define parameters governing its safe use.

The appropriate medical management of methicillin-resistant Staphylococcus aureus in chronic suppurative otitis media

CONCLUSION

Methicillin-resistant Staphylococcus aureus (MRSA) was the most prevalent species (28.1%) in the bacteriological study of 577 patients with chronic suppurative otitis media (CSOM). Frequent and appropriate aural cleansing and irrigation using diluted acetic acid or other solutions such as Burow's solution can be an effective method for the medical treatment of MRSA in CSOM.

OBJECTIVES

To investigate the bacteriological results of 577 patients with CSOM and the medical treatment results of 91 non-cholesteatomatous MRSA patients and to consider the most appropriate medical treatment modality for MRSA in patients with CSOM.

PATIENTS AND METHODS

This study was conducted retrospectively from January 2005 through July 2008 using the medical records of 577 patients with otorrhoea caused by CSOM. We analyzed the bacteriological results by dividing all patients into cholesteatomatous CSOM and non-cholesteatomatous CSOM and investigated the medical treatment results of 91 non-cholesteatomatous MRSA patients. We used three treatment modalities: aural cleansing and irrigation (50 cases), intravenous injection of teicoplanin (22 cases) and intravenous injection of vancomycin (15 cases).

RESULTS

Overall, MRSA (28.1%) was the most prevalent species, followed by methicillin-susceptible Staphylococcus aureus (MSSA) (20.4%), Pseudomonas (18.6%) and coagulase-negative staphylococci (CNS) (15.0%). In non-cholesteatomatous MRSA treatment for dry ear, there were no significant differences between the three groups. The results showed that 79.5% of the group treated with aural cleansing and irrigation succeeded in achieving dry ears in 19.0 days. Similarly, 78.9% of another group with intravenous injection of teicoplanin eventually had dry ears, taking 16.0 days. Finally, the number of patients with dry ear in the group treated with intravenous injection of vancomycin was up to 80% of the total in 15.2 days.

Sinogenic orbital and subperiosteal abscesses: Microbiology and methicillin-resistant Staphylococcus aureus incidence

OBJECTIVE: To assess the current bacteriology and the incidence of methicillin-resistant Staphylococcus aureus in orbital and subperiosteal abscesses of paranasal sinus disease origin.

STUDY DESIGN: Case series with chart review.

SETTING: An otolaryngology and ophthalmology specialty hospital.

SUBJECTS AND METHODS: Fifty-three patients were treated between 1994 and 2008 for orbital or subperiosteal abscess and paranasal sinusitis, confirmed by imaging and surgical intervention; 46 had operative culture specimens and comprise the study cohort.

RESULTS: The mean patient age was 28 years; one third were younger than 18. Nearly twice as many patients had subperiosteal (n = 30) as had orbital abscesses (n = 16). In 12 patients (26%), cultures were negative or grew only skin flora contaminants (coagulase-negative staphylococci, diphtheroids, and Propionibacterium acnes). Fifteen patients (33%) grew more than one pathogen. Streptococci were isolated in 17 of the 46 cases (37%), S. aureus in 13 (28.3%), gram-negative bacilli in eight (17.4%), and anaerobes in nine (19.6%). Methicillin-resistant S. aureus accounted for three (23.1%) of the S. aureus isolates and 6.5 percent of the total cases.

CONCLUSION: Abscess cultures grew a mixture of bacteria, including gram-positive cocci, gram-negative bacilli, and anaerobes. Although streptococci were the most common genus of bacteria isolated, S. aureus was the single most common pathogen recovered and one fourth of these cases were methicillin-resistant S. aureus. Given the significant morbidity that may result from inadequate treatment, an antibiotic active against methicillin-resistant S. aureus should be included in the initial broad-spectrum antimicrobial treatment regimen of orbital and subperiosteal abscesses of sinusitis origin until culture results are available.

© 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

Community-associated methicillin-resistant Staphylococcus aureus: epidemiology and clinical consequences of an emerging epidemic

Staphylococcus aureus is an important cause of skin and soft-tissue infections (SSTIs), endovascular infections, pneumonia, septic arthritis, endocarditis, osteomyelitis, foreign-body infections, and sepsis. Methicillin-resistant S. aureus (MRSA) isolates were once confined largely to hospitals, other health care environments, and patients frequenting these facilities. Since the mid-1990s, however, there has been an explosion in the number of MRSA infections reported in populations lacking risk factors for exposure to the health care system. This increase in the incidence of MRSA infection has been associated with the recognition of new MRSA clones known as community-associated MRSA (CA-MRSA). CA-MRSA strains differ from the older, health care-associated MRSA strains; they infect a different group of patients, they cause different clinical syndromes, they differ in antimicrobial susceptibility patterns, they spread rapidly among healthy people in the community, and they frequently cause infections in health care environments as well. This review details what is known about the epidemiology of CA-MRSA strains and the clinical spectrum of infectious syndromes associated with them that ranges from a commensal state to severe, overwhelming infection. It also addresses the therapy of these infections and strategies for their prevention.

Methicillin-resistant Staphylococcus aureus in middle ear fluid of children

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) infections and colonization in children have increased in recent years.

OBJECTIVE

This study examined the possible effect of this increase on MRSA isolation from middle ear fluid (MEF) of children.

METHOD

A retrospective descriptive study was performed using the electronic medical records of children cared for at the Alfred I. duPont Hospital for Children from 2003 to 2007. All MEF isolates obtained at tympanostomy tube placement for recurrent or chronic otitis media or from spontaneous drainage were tabulated and analyzed. Records of children whose MEF grew S aureus comprised our database.

RESULTS

A total of 920 MEF isolates were reviewed, of which 121 patients with S aureus in the MEF were identified. Twenty were excluded per protocol. In the cohort of 101 patients, 76 had methicillin-sensitive Staphylococcus aureus (MSSA; 75.3%) and 25 had MRSA (24.7%).

CONCLUSION

In this retrospective study, the authors demonstrated that among children with S aureus in the MEF, younger children (<3 years) were more likely to have MRSA.