Impact of Pneumococcal Polysaccharide Vaccine (Prevnar) on Middle Ear Fluid in Children Undergoing Tympanostomy Tube Insertion

Biofilm-Forming Bacteria Implicated in Complex Otitis Media in Children in the Post-Heptavalent Pneumococcal Conjugate Vaccine (PCV7) Era

Background: Chronic media with effusion (COME) and recurrent acute otitis media (RAOM) are closely related clinical entities that affect childhood. The aims of the study were to investigate the microbiological profile of otitis-prone children in the post-PCV7 era and, to examine the biofilm-forming ability in association with clinical history and outcome during a two-year post-operative follow-up. Methods: In this prospective study, pathogens from patients with COME and RAOM were isolated and studied in vitro for their biofilm-forming ability. The minimum inhibitory concentrations (MIC) of both the planktonic and the sessile forms were compared. The outcome of the therapeutic method used in each case and patient history were correlated with the pathogens and their ability to form biofilms. Results: Haemophilus influenzae was the leading pathogen (35% in COME and 40% in RAOM), and Streptococcus pneumoniae ranked second (12% in COME and 24% in RAOM). Polymicrobial infections were identified in 5% of COME and 19% of RAOM cases. Of the isolated otopathogens, 94% were positive for biofilm formation. Conclusions: This is the first Greek research studying biofilm formation in complex otitis media-prone children population in the post-PCV7 era. High rates of polymicrobial infections, along with treatment failure in biofilms, may explain the lack of antimicrobial efficacy in otitis-prone children.

The Formation of Biofilm and Bacteriology in Otitis Media with Effusion in Children: A Prospective Cross-Sectional Study

BACKGROUND

Otitis media with effusion (OME) can cause serious complications such as hearing impairment or development delays. The aim of the study was to assess the microbiological profile of organisms responsible for OME and to determine if a biofilm formation can be observed.

METHODS

Ninety-nine samples from 76 patients aged from 6 months to 12 years were collected for microbiological and molecular studies.

RESULTS

In microbiological studies, pathogenic bacteria Haemophilus influenzae (38.89%), Streptococcus pneumoniae (33.33%), and Staphylococcus aureus MSSA (27.78%), as well as opportunistic bacteria Staphylococcus spp. (74.14%), Diphtheroids (20.69%), Streptococcus viridans (3.45%), and Neisseria spp. (1.72%) were found. The average degree of hearing loss in the group of children with positive bacterial culture was 35.9 dB, while in the group with negative bacterial culture it was 25.9 dB (p = 0.0008). The type of cultured bacteria had a significant impact on the degree of hearing impairment in children (p = 0.0192). In total, 37.5% of Staphylococcus spp. strains were able to form biofilm.

CONCLUSIONS

Staphylococcus spp. in OME may form biofilms, which can explain the chronic character of the disease. Pathogenic and opportunistic bacteria may be involved in the etiopathogenesis of OME. The degree of hearing loss was significantly higher in patients from which the positive bacterial cultures were obtained.

Otitis media with effusion: an effort to understand and clarify the uncertainties

Otitis media with effusion--defined as the accumulation of middle-ear effusion behind an intact tympanic membrane without signs or symptoms of acute infection--is one of the most common causes of hearing loss in children in developed countries, potentially leading to language deficits. Although treatment of chronic or relapsing otitis media with effusion is considered imperative, none of the preventative or nonsurgical management measures currently available have proven effective. Tympanostomy tube placement remains the recommended treatment option for high-risk children or for cases of unresponsive otitis media with effusion. This can be attributed to the uncertainties surrounding its pathogenesis. Multiple factors and several possible pathogenetic models have been proposed to explain the production and persistence of middle-ear effusion; only a few of them are supported by sufficient evidence. In this review, the authors will present current knowledge on the pathogenesis, consequences, diagnosis and management of otitis media with effusion. An effort will be made to clarify those aspects sufficiently supported by evidence-based studies, and to underline those that remain unfounded.

Optimizing the management of community-acquired respiratory tract infections in the age of antimicrobial resistance

Community-acquired respiratory tract infections (CARTIs) are the most common reason for prescribing antibiotics in the primary care setting. However, over the last decade, the management of CARTIs has become increasingly complicated by the steady increase in prevalence of drug-resistant pathogens responsible for these infections. As a result, significant attention has been directed at understanding the mechanisms of pathogen acquisition of resistance, drivers of resistance and methods for preventing the development of resistance. Data from recent surveillance studies suggest a slowing or decline in resistance rates to agents, such as beta-lactams, macrolides, tetracyclines and folic acid metabolism inhibitors. However, resistance to one antimicrobial family--the fluoroquinolones--while still low, appears to be on the increase. This is of significant concern given the rapid increase in resistance noted with older antibiotics in recent history. While the clinical implications of antibacterial resistance are poorly understood, the overall rates of antimicrobial resistance, as reported in recent surveillance studies, do not correspond to current rates of failure in patients with CARTIs. This disconnection between laboratory-determined resistance and clinical outcome has been termed the in vitro-in vivo paradox and several explanations have been offered to explain this phenomenon. Solving the problem of antimicrobial resistance will be multifactorial. Important factors in this effort include the education of healthcare providers, patients and the general healthcare community regarding the hazards of inappropriate antibiotic use, prevention of infections through vaccination, development of accurate, inexpensive and timely point-of-care diagnostic tests to aid in patient assessment, institution of objective treatment guidelines and use of more potent agents, especially those with a focused spectrum of activity, earlier in the treatment of CARTIs as opposed to reserving them as second-line treatment options. Ultimately, the single-most important factor will be the judicious use of antibiotics, as fewer antibiotic prescriptions lead to fewer antimicrobial-resistant bacteria.

Microbiology of middle ear effusions from 292 patients undergoing tympanostomy tube placement for middle ear disease

OBJECTIVE

Otitis media is one of the most commonly diagnosed childhood illnesses. Ideally, culture directed therapy for otitis media would be available, however, the common approach is to treat infections with antibiotics that cover the most common pathogens. The objective of this study is to describe the pathogens cultured from the middle ear effusions (MEE) of patients that underwent tympanostomy tube placement for middle ear disease, compare these results with previous studies, and assess for trends suggestive of changes in the microbiology of these patients.

METHODS

Patients were invited to participate after the decision to place ventilation tubes had been made. A standard anterior-inferior myringotomy was made for placement of the ventilation tube. After myringotomy, patients had their ears suctioned and all effusions were collected for microbiologic analysis.

RESULTS

A total of 292 patients were enrolled in the study, a total of 270 MEE samples were taken. Haemophilus influenzae and Moraxella catarrhalis were seen in 24 of 148 (16.2%) and 15 of 148 (10.1%), respectively. Neisseria meningitidis, Staphylococcus aureus and Corynebacterium species were each identified in 11 of the 148 pathogens isolated (7.4%). Streptococcus pneumoniae was identified in 6 of the 148 isolated pathogens (4.1%).

CONCLUSION

Despite a high number of non-pathogenic bacteria, and a high number of culture negative effusions, we demonstrated pathogen rates consistent with other reports in the literature. Future directions include using more specific techniques such as PCR to better understand the microbiology of middle ear effusions.