Microbiology Of Acute Otitis Media Research Articles

Antibiotic Recommendations for Acute Otitis Media and Acute Bacterial Sinusitis: Conundrum No More.

There has been a substantial change in the prevalence and microbiologic characteristics of cases of acute otitis media secondary to the widespread use of pneumococcal conjugate vaccines. Current trends in nasopharyngeal colonization and the microbiology of acute otitis media support a change in the recommendation for antibiotic management of acute otitis media and acute bacterial sinusitis in children.

Predominant Bacteria Detected from the Middle Ear Fluid of Children Experiencing Otitis Media: A Systematic Review.

BackgroundOtitis media (OM) is amongst the most common childhood diseases and is associated with multiple microbial pathogens within the middle ear. Global and temporal monitoring of predominant bacterial pathogens is important to inform new treatment strategies, vaccine development and to monitor the impact of vaccine implementation to improve progress toward global OM prevention.MethodsA systematic review of published reports of microbiology of acute otitis media (AOM) and otitis media with effusion (OME) from January, 1970 to August 2014, was performed using PubMed databases.ResultsThis review confirmed that Streptococcus pneumoniae and Haemophilus influenzae, remain the predominant bacterial pathogens, with S. pneumoniae the predominant bacterium in the majority reports from AOM patients. In contrast, H. influenzae was the predominant bacterium for patients experiencing chronic OME, recurrent AOM and AOM with treatment failure. This result was consistent, even where improved detection sensitivity from the use of polymerase chain reaction (PCR) rather than bacterial culture was conducted. On average, PCR analyses increased the frequency of detection of S. pneumoniae and H. influenzae 3.2 fold compared to culture, whilst Moraxella catarrhalis was 4.5 times more frequently identified by PCR. Molecular methods can also improve monitoring of regional changes in the serotypes and identification frequency of S. pneumoniae and H. influenzae over time or after vaccine implementation, such as after introduction of the 7-valent pneumococcal conjugate vaccine.ConclusionsGlobally, S. pneumoniae and H. influenzae remain the predominant otopathogens associated with OM as identified through bacterial culture; however, molecular methods continue to improve the frequency and accuracy of detection of individual serotypes. Ongoing monitoring with appropriate detection methods for OM pathogens can support development of improved vaccines to provide protection from the complex combination of otopathogens within the middle ear, ultimately aiming to reduce the risk of chronic and recurrent OM in vulnerable populations.

Etiology and antimicrobial susceptibility of middle ear fluid pathogens in Costa Rican children with otitis media before and after the introduction of the 7-valent pneumococcal conjugate vaccine in the National Immunization Program: acute otitis media microbiology in Costa Rican children.

Acute otitis media (AOM) microbiology was evaluated in children after 7-valent pneumococcal conjugate vaccine (PCV7) introduction in Costa Rica (private sector, 2004; National Immunization Program, 2009).This was a combined prospective and retrospective study conducted in a routine clinical setting in San José, Costa Rica. In the prospective part of the study, which was conducted post-PCV7 introduction (2010–2012), standard bacteriological procedures were used to evaluate the etiology and serotype distribution of middle ear fluid samples collected by tympanocentesis or otorrhea from children aged 3–59 months diagnosed with AOM. E-tests were used to evaluate antimicrobial susceptibility in culture-positive samples. Retrospective data recorded between 1999 and 2004 were used for comparison of bacterial etiology and serotype distribution before and after PCV7 introduction. Statistical significance was evaluated in bivariate analyses at the P-value < 0.05 level (without multiplicity correction).Post-PCV7 introduction, Haemophilus influenzae was detected in 118/456 and Streptococcus pneumoniae in 87/456 AOM episodes. Most H. influenzae isolates (113/118) were non-typeable. H. influenzae was more (27.4% vs 20.8%) and S. pneumoniae less (17.1% vs 25.5%) frequently observed in vaccinated (≥2 PCV7 doses or ≥1 PCV7 dose at >1 year of age) versus unvaccinated children. S. pneumoniae non-susceptibility rates were 1.1%, 34.5%, 31.7%, and 50.6% for penicillin, erythromycin, azithromycin, and trimethoprim/sulfamethoxazole (TMP-SMX), respectively. H. influenzae non-susceptibility rate was 66.9% for TMP-SMX. Between pre- and post-PCV7 introduction, H. influenzae became more (20.5% vs 25.9%; P-value < 0.001) and S. pneumoniae less (27.7% vs 19.1%; P-value = 0.002) prevalent, and PCV7 serotype proportions decreased among pneumococcal isolates (65.8% vs 43.7%; P-value = 0.0005). Frequently identified pneumococcal serotypes were 19F (34.2%), 3 (9.7%), 6B (9.7%), and 14 (9.7%) pre-PCV7 introduction, and 19F (27.6%), 14 (8.0%), and 35B (8.0%) post-PCV7 introduction.Following PCV7 introduction, a change in the distribution of AOM episodes caused by H. influenzae and pneumococcal serotypes included in PCV7 was observed in Costa Rican children. Pneumococcal vaccines impact should be further evaluated following broader vaccination coverage.

Clinical Characteristics and Microbiology of Acute Otitis Media of Children: Multicenter Studies

Clinical Characteristics and Microbiology of Acute Otitis Media of Children: Multicenter Studies

Clinical manifestations and microbiology of acute otitis media with spontaneous otorrhea in children

In Taiwan, clinical and microbiological data on acute otitis media (AOM) with spontaneous otorrhea in children are limited. We retrospectively collected data on children with AOM and spontaneous otorrhea between January 2011 and June 2012. Otorrhea samples were collected using sterile swabs and sent for cultures. Pathogens found were Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pyogenes, and Staphylococcus aureus. Pneumococcal isolates collected from October 2011 to June 2012 were serotyped. A total of 92 patients were enrolled in the study for demographic and microbiological analysis. Their median age was 2.5 years. After excluding those with lobar pneumonia, 84 patients were included for analysis of clinical manifestation. The mean febrile duration was 6 days. Leukocytosis and C-reactive protein (CRP) level >50mg/L were noted in 29 (34.5%) patients and 38 (45.2%) patients, respectively. Patients with pneumococcal infection were older (p=0.007) and had more severe symptoms [fever (p=0.001), otalgia (p=0.055), respiratory symptoms (p=0.002-0.03), and higher CRP level (p=0.015)] than children with other bacterial infection. Otorrhea cultures were obtained from 69 (75%) patients, of whom 52 had definitive AOM pathogens. The most common causative pathogen was S. pneumoniae (61.5%), followed by S. aureus (36.5%). Serotype 19A accounted for two-thirds of pneumococcal isolates and had a high rate of nonsusceptibility to penicillin (66.7%) and ceftriaxone (83.3%). S. pneumoniae was found to be the most important source of AOM with spontaneous otorrhea in children and caused more severe symptoms. Serotype 19A, which was usually nonsusceptible to antimicrobial agents, was the most prevalent serotype in these patients.

A retrospective evaluation of microbiology of acute otitis media complicated by spontaneous otorrhea in children living in Milan, Italy

To evaluate the microbiology of acute otitis media (AOM) with otorrhea due to spontaneous tympanic membrane perforation (STMP) in children living in Milan, Italy. We evaluated middle ear fluid (MEF) specimens taken from children affected by AOM associated with STMP and otorrhea between January 2001 and December 2011. The fluid was collected by means of direct swab sampling, sent for culture, and processed within 4 h. A total of 705 specimens were obtained from 458 children (233 boys; mean age ± SD 28.3 ± 19.9 months), and were positive for bacteria in 487 cases (69.1 %). The most frequently cultured infectious agent in single-pathogen cultures was Haemophilus. influenzae (51.0 %), followed by Streptococcus pneumoniae (19.4 %), Streptococcus pyogenes (17.4 %), and Staphylococcus aureus (10.7 %). After adjusting for the sub-period of data collection, age, gender, and previous full heptavalent pneumococcal conjugate vaccine (PCV-7) schedule, it was found that the prevalence of H. influenzae slightly increased in 2008-2010, and the prevalence of S. pneumoniae significantly decreased over time (p = 0.02). AOM with STMP is a particular form of AOM in which S. pyogenes plays a significant causative role although, as in uncomplicated cases, H. influenzae and S. pneumoniae retain their etiological importance. The frequency of the detection of S. aureus in MEF deserves further study because this pathogen can give rise to severe clinical problems. Finally, although the use of PCV-7 was relatively efficacious, the benefit of pneumococcal vaccination would be increased by vaccines including a larger number of serotypes.

Pathogens Implicated in Acute Otitis Media Failures After 7-valent Pneumococcal Conjugate Vaccine Implementation in France

Before 7-valent pneumococcal conjugate vaccine (PCV7) implementation in France, several studies had described the microbiology of acute otitis media (AOM) treatment failures. The causative pathogens were Streptococcus pneumoniae (Sp) followed by nontypable Haemophilus influenzae (NTHi). The aim of this study was to describe the epidemiology of pathogens involved in AOM treatment failures or recurrences. This French multicentric prospective study enrolled 143 children with AOM treatment failure between 2007 and 2009 observed by 8 ear, nose, and throat specialists. Failure was defined as the persistence of AOM symptoms after at least 48 hours of antibiotic therapy or their recurrence within 4 days after the end of treatment. Standardized history and physical examination findings were recorded, and culture of middle ear fluid (MEF) was obtained. Mean age was 16.9 ± 9.9 months (median, 13.7). Eighty-eight percent of children had received more than 1 dose of PCV7, and 70.6% attended day care. The most common antibiotic used at the time of treatment failure or recurrence was a combination of amoxicillin and clavulanate (51.1%). Bacteriologic sampling demonstrated that in 35% of cases (n=50), no otopathogen was cultured at the time of treatment failure or recurrence. Similar proportions of Sp and NTHi were observed in the 86 patients (60.1%) from whom only a single species was recovered from MEF (46.5% for Sp, n=40 and 45.3% for NTHi, n=39). Among Sp strains, 4.4% were penicillin susceptible, 77.8% were penicillin intermediate, and 17.8% were fully penicillin resistant, and serotype 19A represented 84.5% of all serotypes detected. Among NTHi isolates, 15.5% (n=7) were β-lactamase-producing strains (including 2 strains with only this mechanism of resistance), and strains with reduced susceptibility by changes in protein binding to penicillin (β-lactamase-negative ampicillin resistant strains) represented 35.5% of cases. Among the 50 sterile MEF samples, polymerase chain reaction was performed in 32, of which 4 were positive for HI, 3 for Sp, and 3 for both. Among children with AOM treatment failures in France, Sp and NTHi were equally distributed; 19A was the main Sp serotype, and the main resistance mechanism for NTHi was β-lactamase-negative ampicillin resistance.

Prevalence of serotypes of Streptococcus pneumoniae and other agents that cause acute otitis media in children in Latin America. A systematic review of the literature

Acute otitis media (AOM) is a common diagnosis in children. Streptococcus pneumoniae remains the most prevalent agent worldwide, followed by Haemophilus influenzae. However, the introduction of pneumococcal vaccines has changed the microbiology of AOM. To establish the prevalence of pneumococcal serotypes and other common germs in Latin American children with AOM. We carried out a systematic search for original articles in seven databases, limited to publications between 1999 and 2010, children under 18, and English and Spanish languages. Search was completed with "snowball" strategy. Eligibility criteria included original prevalence cross-sectional articles, conducted in pediatric populations in Latin America, with homogeneous inclusion and exclusion criteria. Relevant information was extracted from the selected articles. Eleven articles met the eligibility criteria. In Latin America, specifically Costa Rica, Chile, Brazil and Argentina, Streptococcus pneumoniae (43.5%) was the most frequent germ, (serotype 19F is the most frequent, except in Argentina where it is 14) followed by Haemophilus influenzae (30%) and Moraxella catarrhalis (6.4%). The more prevalent germ in Latin American children AOM is Streptococcus pneumoniae, a finding consistent with those from Europe and the U.S. Further studies are required in the other countries of the region and its pediatric pneumococcal vaccinated population, in order to establish an updated epidemiological and microbiological profile in Latin America.

Past, present, and future: An overview of the microbiology of acute otitis media

Past, present, and future: An overview of the microbiology of acute otitis media

Past, present, and future: an overview of the microbiology of acute otitis media.

Helpful new treatment guidelines offer physicians structure in diagnosing and treating patients who have uncomplicated acute otitis media (AOM). These guidelines should be weighed in light of the evolving microbiology of AOM pathogens. Physicians must be cognizant of the cyclical changes in bacteria as well as new vaccines and antibiotics best suited to address AOM. Although pneumococcal vaccines have helped, serotype shifts and bacterial resistance could work against current treatment practices. Physicians should understand causal organisms and treat patients appropriately to mitigate antibiotic resistance. New vaccines in development may offer additional reduction in AOM and drug resistant pneumococcus in the future.

Update: Acute Otitis Media

CME EDUCATIONAL OBJECTIVES 1. Review the recent changes in the microbiology of acute otitis media. 2. Differentiate the physical exam findings characteristic of acute otitis media (AOM) from those of otitis media with effusion (OME). 3. Discuss the evidence to support antimicrobial management of AOM in children.

Diagnosis, Microbial Epidemiology, and Antibiotic Treatment of Acute Otitis Media in Children

Acute otitis media (AOM) is the most common condition for which antibiotics are prescribed for US children; however, wide variation exists in diagnosis and treatment. To perform a systematic review on AOM diagnosis, treatment, and the association of heptavalent pneumococcal conjugate vaccine (PCV7) use with AOM microbiology. PubMed, Cochrane Databases, and Web of Science, searched to identify articles published from January 1999 through July 2010. Diagnostic studies with a criterion standard, observational studies and randomized controlled trials comparing AOM microbiology with and without PCV7, and randomized controlled trials assessing antibiotic treatment. Independent article review and study quality assessment by 2 investigators with consensus resolution of discrepancies. Of 8945 citations screened, 135 were included. Meta-analysis was performed for comparisons with 3 or more trials. Few studies examined diagnosis; otoscopic findings of tympanic membrane bulging (positive likelihood ratio, 51 [95% confidence interval {CI}, 36-73]) and redness (positive likelihood ratio, 8.4 [95% CI, 7-11]) were associated with accurate diagnosis. In the few available studies, prevalence of Streptococcus pneumoniae decreased (eg, 33%-48% vs 23%-31% of AOM isolates), while that of Haemophilus influenzae increased (41%-43% vs 56%-57%) pre- vs post-PCV7. Short-term clinical success was higher for immediate use of ampicillin or amoxicillin vs placebo (73% vs 60%; pooled rate difference, 12% [95% CI, 5%-18%]; number needed to treat, 9 [95% CI, 6-20]), while increasing the rate of rash or diarrhea by 3% to 5%. Two of 4 studies showed greater clinical success for immediate vs delayed antibiotics (95% vs 80%; rate difference, 15% [95% CI, 6%-24%] and 86% vs 70%; rate difference, 16% [95% CI, 6%-26%]). Data are absent on long-term effects on antimicrobial resistance. Meta-analyses in general showed no significant differences in antibiotic comparative effectiveness. Otoscopic findings are critical to accurate AOM diagnosis. AOM microbiology has changed with use of PCV7. Antibiotics are modestly more effective than no treatment but cause adverse effects in 4% to 10% of children. Most antibiotics have comparable clinical success.

Microbiology of otitis media: A moving target

The microbiology of acute otitis media (AOM) is linked to the nasopharyngeal commensal flora. This respiratory ecosystem undergoes various selective pressures, such as antibiotic consumption and vaccine use. Socio-economic conditions also influence the bacterial composition of the nasopharynx. Streptococcus pneumoniae, non-encapsulated Haemophilus influenzae, Moraxella catarrhalis, and group A Streptococcus are the leading causes of bacterial AOM worldwide. This paper will discuss the causes and consequences of recent shifts in the underlying microbiology of AOM.

Pediatric Mastoiditis in the Pneumococcal Conjugate Vaccine Era

The microbiology of acute otitis media has changed in the heptavalent pneumococcal conjugate vaccine (PCV) era. We hypothesize similar changes with pediatric mastoiditis. To compare the etiology of mastoiditis in the pre-PCV (January 1995-December 2000) and post-PCV (January 2001- April 2005) eras to guide empiric antimicrobial therapy in the pediatric emergency department. Retrospective chart review of all patients admitted with a diagnosis of mastoiditis from January 1995 to April 2005. : One hundred twenty-two charts were reviewed, 68 pre-PCV and 54 post-PCV. Etiological agents were determined by culture results in 60 patients. The most common bacterial isolates were Streptococcus pneumoniae (24), Pseudomonas aeruginosa (12), Staphylococcus aureus (12), Streptococcus pyogenes (8), and Haemophilus influenzae (2). There was no reduction in mastoiditis due to S. pneumoniae from the pre-PCV to the post-PCV eras (odds ratio [OR], 0.9; 95% confidence interval [CI], 0.4-2.1; P = 0.77). Ceftriaxone nonsusceptibility was seen in 30% of post-PCV S. pneumoniae isolates compared with 7% of pre-PCV isolates. Acute mastoiditis was diagnosed in 93 patients, and chronic mastoiditis (defined as >or=3 wk of symptoms) was diagnosed in 29 patients. Streptococcus pneumoniae was more likely to be implicated in acute versus chronic mastoiditis (OR, 9.2; 95% CI, 1.2-52.2; P = 0.01). Pseudomonas aeruginosa was more frequently implicated in chronic versus acute mastoiditis (OR, 16.4; 95% CI, 2.1-75.8; P = 0.0003). There was no difference in the proportion of pediatric mastoiditis cases caused by S. pneumoniae in the pre-PCV versus post-PCV eras. Empiric antimicrobial therapy with ceftriaxone alone is not sufficient in the post-PCV era.

Microbiology of Acute Otitis Media in Children with Tympanostomy Tubes: Prevalences of Bacteria and Viruses

Background. Bacteria are found in 50%–90% of cases of acute otitis media (AOM) with or without otorrhea, and viruses are found in 20%–49% of cases. However, for at least 15% of patients with AOM, the microbiological etiology is never determined. Our aim was to specify the full etiology of acute middle ear infection by using modern microbiological methods concomitantly for bacterial and viral detection. Methods. The subjects were 79 young children having AOM with new onset (<48 h) of otorrhea through a tympanostomy tube. Middle ear fluid samples were suctioned from the middle ear through the tympanostomy tube. Bacteria were sought by culture and polymerase chain reaction; viruses were analyzed by culture, antigen detection, and polymerase chain reaction. Results. At least 1 respiratory tract pathogen was noted in 76 children (96%). Bacteria were found in 73 cases (92%), and viruses were found in 55 (70%). In 52 patients (66%), both bacteria and viruses were found. Bacteria typical of AOM were detected in 86% of patients. Picornaviruses accounted for 60% of all viral findings. Conclusions. In the great majority of children, AOM is a coinfection with bacteria and viruses. The patent tympanostomy tube does not change the spectrum of causative agents in AOM. A microbiological etiology can be established in practically all cases.

Brief review of the clinical effectiveness of PREVENAR ® against otitis media

Pre-licensure trials in Finnish and US infants demonstrated that PREVENAR was associated, respectively, with a 6% (95% CI, −4% to 16%) and an 8.9% (95% CI, 5.8–11.8%) overall reduction in clinical AOM incidence. Long-term follow-up of these cohorts revealed that there was an approximately 10–50% vaccine efficacy against recurrent otitis media or for the prevention of tympanostomy tube placement. In surveillance reports from the USA that followed infants with serious AOM, generalized PREVENAR vaccination led to an important fall in the incidence of pneumococcal otitis media, particularly for cases that would have been frequent or would have been refractory to antibiotic treatment. The rate of pneumococcal MEF isolates fell by 39% for severe otitis media [McEllistrem MC, Adams JM, Patel K, Mendelsohn AB, Kaplan SL, Bradley JS, et al. Acute otitis media due to penicillin-nonsusceptible Streptococcus pneumoniae before and after the introduction of the pneumococcal conjugate vaccine. Clin Infect Dis 2005;40(12):1738–44], by 42%, among persistent or treatment-resistant otitis media [Casey JR, Pichichero ME, Changes in frequency and pathogens causing acute otitis media in 1995–2003. Pediatr Infect Dis J 2004;23(9):824–8 [see comment]] and by 66% among severe otitis media cases or from ‘otitis-prone’ children [Block SL, Hedrick J, Harrison CJ, Tyler R, Smith A, Findlay R, et al. Community-wide vaccination with the heptavalent pneumococcal conjugate significantly alters the microbiology of acute otitis media. Pediatr Infect Dis J 2004;23(9):829–33 [see comment]].

Microbiology of acute otitis media with perforation (AOMwiP) in Aboriginal children living in remote communities—monitoring the impact of 7-valent pneumococcal conjugate vaccine (7vPCV)

In young Aboriginal children with new episodes of AOMwiP, Haemophilus influenzae (57%), Streptococcus pneumoniae (34%) and Streptococcus pyogenes (6%) are the major pathogens recovered from ear discharge. In children immunised with pneumococcal conjugate vaccine, there were fewer vaccine type pneumococci and more vaccine-related type pneumococci than unimmunized children. Replacement of vaccine types by non-pneumococcal pathogens was not detected.

Current face of acute otitis media: Microbiology and prevalence resulting from widespread use of heptavalent pneumococcal conjugate vaccine

Background: Many causes can be proposed for achange in the microbiologic makeup of a specific disease state. However, when viewed through the scope of recent events, only one is likely to be the true cause of a change in the microbiology of acute otitis media (AOM): the release and widespread use of heptavalent pneumococcal conjugate vaccine (PCV-7). Objective: The aim of this report was to review themicrobiology and prevalence of AOM before and after the release and widespread use of PCV-7. Methods: For this brief review, we used a MEDLINEsearch to identify English-language literature related to the microbiology of AOM before and after the release of PCV-7 in 2000 in the United States (key terms: acute otitis media, AOM, Haemophilus influenzae, H influenzae, Streptococcus pneumoniae, and S pneumoniae; years: 1980–2005). Studies using tympanocentesis to identify the pathogen in recurrent or persistent AOM were examined; US studies reporting AOM microbiology before and after the release of PCV-7 in the same population were considered for the post-PCV-7 analysis. Results: Following the release of PCV-7, a decreasein the overall rates of AOM was noted. This decrease brings into question the resultant effect on the microbiology of AOM. Our literature search revealed 2 studies that examined the microbiology of AOM before and after the release of PCV-7 in the United States. These 2 studies, conducted in dispersed geographic regions (rural Kentucky and Rochester, New York), illustrated a change in the predominant causative pathogen in AOM, from S pneumoniae to H influenzae in the population of children 7 to 24 months of age with recurrent AOM. Given the time period of the change, these shifts could be related to the release and widespread use of PCV-7. Conclusions: Since the 1990s, the predominantcausative pathogen in recurrent AOM changed from S pneumoniae to H influenzae, possibly as a result of the release and widespread use of PCV 7. Although PCV-7 use was slowed from August 2001 to May 2003 and again from February to September 2004 by nationwide shortages, those shortages have now been resolved, and compliance with the full vaccine schedule is expected to increase.

Microbiology of Acute Otitis Media With Tympanostomy Tubes

Microbiology of Acute Otitis Media With Tympanostomy Tubes

Particularities of bacterial ecology of acute otitis media in an African subtropical country (Cote d’Ivoire)

Acute otitis media (AOM) is the commonest infectious disease of childhood. Its treatment is based on a probabilistic antibiotic therapy. To determine the prevalence of different bacteria responsible for AOM in children in Abidjan (Côte d'Ivoire). This is a prospective study, between November 2002 and August 2003. To identify bacterial isolates, 60 children under 15 years old with AOM were enrolled. In 52 cases, the sample was recovered by aspiration of a spontaneous otorrhea and in eight cases, it was taken by paracentesis. Nasopharyngeal swabs were cultured. Antibiotic susceptibility tests were performed on isolates. 75% of children were under 24 months of age. Pseudomonas aeruginosa was recovered in 31.8% of cases followed by Streptococcus pneumoniae (21%), Proteus (7.4%) and Staphylococcus (6.2%). The rate of penicillin-nonsusceptible S. pneumoniae (NSSP) was 11.8%. Resistance to erythromycin was 6%. For Pseudomonas, resistances to antibiotics were 35.5% to ceftazidim and 16% to pefloxacin, respectively, but all the strains were sensible to colistin, iminepem and ciprofloxacin. These data can modify therapeutic approaches for treatment of AOM in our country. This study should encourage surveillance of AOM microbiology.