Identification of Turicella otitidis isolated from a patient with otorrhea associated with surgery: differentiation from Corynebacterium afermentans and Corynebacterium auris

Metabolism and gene sequence variation in Turicella otitidis implies its adaptability and pathogenicity in extra-otic infection: a systematic review

Turicella otitidis belongs to the Corynebacteriaceae family and is a normal inhabitant of the ear and exists in a commensal relationship with its host. In children, T. otitidis is frequently associated with otitis media. The emergence of Turicella otitidis as a pathogen is concerning, particularly due to the limited availability of data on its pathogenic properties. The objective of this study is to conduct a systematic review of T. otitidis infections occurring in both the ear and other anatomical sites, and to summarize the differences in metabolism and genome sequences between isolates obtained from the ear and blood.

Comparison of Conventional Methods, Automated Systems, and DNA Sequence Analysis Methods in the Identification of Corynebacterium afermentans and Corynebacterium mucifaciens Bacteria Isolated from Blood and Catheter Culture Samples

The aim of this study is to compare different methods due to the difficulties in identifying coryneform bacteria to species level and to determine antibiotic resistance profiles. Isolates identified as Turicella otitidis (n:45) by VITEK 2 Compact and Corynebacterium mucifaciens (n:1) by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), isolated from blood and catheter cultures between 2015 and 2017 were included in the study. For identification of the isolates, conventional tests and 16S rDNA sequence analysis were performed. Antibiotic susceptibilities of the isolates were determined by Etest. The isolates identified as T. otitidis with VITEK 2 Compact could not be identified by MALDI-TOF MS and described as C. mucifaciens/Corynebacterium afermentans spp. by 16S rDNA sequence analysis. One isolate identified as C. mucifaciens by MALDI-TOF MS could not be identified with VITEK 2 Compact and described as C. mucifaciens by 16S rDNA sequence analysis and conventional methods. All isolates (n:45) described as C. mucifaciens/C. afermentans spp. by 16S rDNA sequence analysis were identified as C. afermentans subsp. afermentans with conventional methods. All 45 isolates identified as C. afermentans subsp. afermentans were resistant to penicillin, erythromycin, and clindamycin and were susceptible to vancomycin and daptomycin, whereas 31 (69%) were resistant to trimethoprim-sulfamethoxazole (TMP-SXT). The isolate identified as C. mucifaciens was susceptible to penicillin, vancomycin, daptomycin, and TMP-SXT; it was resistant to erythromycin and clindamycin. In this study, we reported 45 C. afermentans isolates misidentified as T. otitidis in routine laboratory processes. To our knowledge, this is the first study to include the highest number of C. afermentans blood isolates.

Reviewing the Pathogenic Potential of the Otitis-Associated Bacteria Alloiococcus otitidis and Turicella otitidis

Alloiococcus otitidis and Turicella otitidis are common bacteria of the human ear. They have frequently been isolated from the middle ear of children with otitis media (OM), though their potential role in this disease remains unclear and confounded due to their presence as commensal inhabitants of the external auditory canal. In this review, we summarize the current literature on these organisms with an emphasis on their role in OM. Much of the literature focuses on the presence and abundance of these organisms, and little work has been done to explore their activity in the middle ear. We find there is currently insufficient evidence available to determine whether these organisms are pathogens, commensals or contribute indirectly to the pathogenesis of OM. However, building on the knowledge currently available, we suggest future approaches aimed at providing stronger evidence to determine whether A. otitidis and T. otitidis are involved in the pathogenesis of OM. Such evidence will increase our understanding of the microbial risk factors contributing to OM and may lead to novel treatment approaches for severe and recurrent disease.

The Mycobacterial Cell Envelope: A Relict From the Past or the Result of Recent Evolution?

Mycobacteria are well known for their taxonomic diversity, their impact on global health, and for their atypical cell wall and envelope. In addition to a cytoplasmic membrane and a peptidoglycan layer, the cell envelope of members of the order Corynebacteriales, which include Mycobacterium tuberculosis, also have an arabinogalactan layer connecting the peptidoglycan to an outer membrane, the so-called “mycomembrane.” This unusual cell envelope composition of mycobacteria is of prime importance for several physiological processes such as protection from external stresses and for virulence. Although there have been recent breakthroughs in the elucidation of the composition and organization of this cell envelope, its evolutionary origin remains a mystery. In this perspectives article, the characteristics of the cell envelope of mycobacteria with respect to other actinobacteria will be dissected through a molecular evolution framework in order to provide a panoramic view of the evolutionary pathways that appear to be at the origin of this unique cell envelope. In combination with a robust molecular phylogeny, we have assembled a gene matrix based on the presence or absence of key determinants of cell envelope biogenesis in the Actinobacteria phylum. We present several evolutionary scenarios regarding the origin of the mycomembrane. In light of the data presented here, we also propose a novel alternative hypothesis whereby the stepwise acquisition of core enzymatic functions may have allowed the sequential remodeling of the external cell membrane during the evolution of Actinobacteria and has led to the unique mycomembrane of slow-growing mycobacteria as we know it today.

Turicella otitidis and Corynebacterium auris: 20 years on

Turicella otitidis and Corynebacterium auris, described as new species 20 years ago, have been isolated mainly from the external ear canal and middle ear fluid. While their taxonomic position has been clearly established, their diagnosis in the routine laboratory is difficult. The question of their pathogenic potential in otitis is still open but might be elucidated better if corynebacteria are speciated more often.

Draft genome sequence of Turicella otitidis ATCC 51513, isolated from middle ear fluid from a child with otitis media

Turicella otitidis is an unusual corynebacterium with a controversial role in otitis media in children. Metabolic capabilities deduced from the draft genome indicate its adaptation to habitats on the human skin and in the intestine. The lack of candidate virulence factors implies that T. otitidis has a low pathogenic potential.

[Turicella otitidis infection: otitis media complicated by mastoiditis]

Turicella otitidis is a nonfermentative, Gram-positive bacillus, which is almost exclusively isolated from the ear. Few cases of infection caused by T. otitidis have been reported in the literature, but the pathogenic potential of this little-known bacterium remains controversial, particularly in acute and chronic otitis media.

CLINICAL OBSERVATIONS

A retrospective study of T. otitidis isolated in the University Hospital of Montpellier in 2004 found T. otitidis in 13 patients. Among them, a 3-year-old girl had presented with acute and perforated otitis media and mastoiditis caused by T. otitidis, thereby confirming the pathogenic effect of this bacterium.

CONCLUSION

T. otitidis is relatively frequently isolated from middle ear samples in healthy patients. However, T. otitidis has been implicated in serious cases of infection and should be considered an opportunistic pathogen. Its clinical significance can be difficult to establish and each case should be carefully interpreted. From a bacteriological point of view, T. otitidis should be precisely identified to obtain more information regarding its role in clinical pathology.

Characterization of a truncated lipoarabinomannan from the Actinomycete Turicella otitidis

Lipoarabinomannan (LAM) lipoglycans have been characterized from a range of mycolic acid-containing actinomycetes and from the amycolate actinomycete Amycolatopsis sulphurea. To further understand the structural diversity of this family, we have characterized the lipoglycan of the otic commensal Turicella otitidis. T. otitidis LAM (TotLAM) has been determined to consist of a mannosyl phosphatidylinositol anchor unit carrying an (alpha 1-->6)-linked mannan core and substituted with terminal-arabinosyl branches. Thus, TotLAM has a novel truncated LAM structure. Using the human monocytic THP-1 cell line, it was found that TotLAM exhibited only minimal ability to induce tumor necrosis factor alpha. These findings contribute further to our understanding of actinomycete LAM diversity and allow further speculation as to the correlation between LAM structure and the immunomodulatory activities of these lipoglycans.

Acute and chronic otitis media and Turicella otitidis: a controversial association

Turicella otitidis is a non-fermenting Gram-positive bacillus isolated almost exclusively from ear exudates. Its significance in acute or chronic otitis media is controversial. Over a 12-month period, T. otitidis was isolated from nine ear exudates from seven patients. Most of these were cases of spontaneous drainage following recurrence of otitis media after antimicrobial therapy that was ineffective against T. otitidis. The MICs of penicillin, levofloxacin, linezolid and vancomycin were very low for all the isolates studied, but most isolates displayed high resistance to macrolides and lincosamides.

Turicella otitidis and Corynebacterium auris do not cause otitis media with effusion in children

BACKGROUND

The recently described coryneform bacteria and were first detected in the middle ear of patients with acute otitis media and chronic otitis media. Whether these bacteria play an essential role in the pathogenesis of otitis media with effusion (OME) is unclear.

METHODS

In a prospective study 60 children with OME and 205 controls were evaluated to determine the incidence of and. Swabs from the external auditory canal (EAC) and the middle ear effusion (MEE) of OME children undergoing tympanotomy, ventilation tube insertion or both were cultured. Swabs from the EAC from healthy children served as controls.

RESULTS

In control children was found in EAC swabs from 23 of 205 (11.2%) and in 32 of 205 (15.6%). was isolated from 14 of 60 (23.3%) OME patients from the EAC only and in 6 of 60 (10.0%) OME patients from both EAC and MEE. was isolated in 2 of 60 (3.3%) from the EAC only and in 1 of 60 (1.7%) from both EAC and MEE. In no patient did or grow exclusively from MEE.

CONCLUSION

and may be part of the normal bacterial flora of the EAC in some children. Neither organism seems to cause OME in children.

Microbiology of normal external auditory canal

OBJECTIVES

To isolate and characterize bacteria and fungi from the healthy ear and to obtain susceptibility profiles on each bacterial isolate.

STUDY DESIGN

Prospective.

METHODS

Specimens were collected from the external canals and cerumen of healthy subjects. Species-level identification was obtained by combining phenotypic and genotypic data. End-point minimal inhibitory concentration testing was performed using National Committee for Clinical Laboratory Standards recommended methods.

RESULTS

One hundred sixty-four subjects were cultured. Seventeen canal and 16 cerumen specimens showed no growth. One hundred forty-eight cerumen specimens yielded 314 organisms, including 23 fungi. One hundred forty-seven canal specimens yielded 310 organisms, including 7 fungi. Of 291 bacteria isolated from cerumen, 99% were Gram-positive. Of 302 bacteria isolated from the canal, 96% were Gram-positive. Staphylococci were 63% of both the cerumen bacteria and the canal bacteria. Coryneforms represented 22% of the bacteria in cerumen and 19% in the canal. Turicellaotitidis was the primary coryneform isolated from both the canal and the cerumen. Streptococci-like bacteria were 10% from the cerumen, 7% from the canal. In both cerumen and canal, Alloiococcusotitis was more than 95% of the streptococci-like bacteria. Fifteen gram-negative organisms were isolated from the canal and cerumen, including four Pseudomonas aeruginosa strains. The percentages of Staphylococcus epidermidis isolates that had high-level resistance (> or =8 microg/mL) were as follows: to neomycin, 28% from cerumen and 11% from the canal; to oxacillin, 28% from cerumen and 25% from the canal; and to ofloxacin, 15% from cerumen and 19% from the canal.

CONCLUSIONS

Turcellaotitidis and A. otitidis were present with a much higher frequency than previously described, lending evidence that they be considered normal otic flora. Corynebacterium auris, previously reported only in children, was isolated from normal adults.

Turicella otitidis as an unusual agent causing a posterior auricular abscess

A posterior auricular abscess in a 3-year-old girl was confirmed to have been caused by an unusual organism, Turicella otitidis.

Turicella otitidis mastoiditis in a healthy child

Turicella otitidis, a coryneform bacterium, has been associated with acute otitis media. A 5-year-old girl developed acute mastoiditis. Turicella was isolated from the right and left middle ear fluid.

Multicenter evaluation of the updated and extended API (RAPID) Coryne database 2.0

In a multicenter study, 407 strains of coryneform bacteria were tested with the updated and extended API (RAPID) Coryne system with database 2.0 (bioMérieux, La-Balme-les-Grottes, France) in order to evaluate the system's capability of identifying these bacteria. The design of the system was exactly the same as for the previous API (RAPID) Coryne strip with database 1.0, i.e., the 20 biochemical reactions covered were identical, but database 2.0 included both more taxa and additional differential tests. Three hundred ninety strains tested belonged to the 49 taxa covered by database 2.0, and 17 strains belonged to taxa not covered. Overall, the system correctly identified 90.5% of the strains belonging to taxa included, with additional tests needed for correct identification for 55.1% of all strains tested. Only 5.6% of all strains were not identified, and 3.8% were misidentified. Identification problems were observed in particular for Corynebacterium coyleae, Propionibacterium acnes, and Aureobacterium spp. The numerical profiles and corresponding identification results for the taxa not covered by the new database 2.0 were also given. In comparison to the results from published previous evaluations of the API (RAPID) Coryne database 1.0, more additional tests had to be performed with version 2.0 in order to completely identify the strains. This was the result of current changes in taxonomy and to provide for organisms described since the appearance of version 1.0. We conclude that the new API (RAPID) Coryne system 2.0 is a useful tool for identifying the diverse group of coryneform bacteria encountered in the routine clinical laboratory.