A hypothesis-forming exploratory cross-sectional assessment was conducted to assess the occurrence and relevance of Gram-positive rod-shaped bacteria like Corynebacterium spp. and Actinomycetaceae in human urine samples. In total, 1170 urine samples from 1031 inpatients with suspected urinary tract infection were assessed for culture-based growth of Gram-positive rod-shaped bacteria applying API Coryne assays, matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and in-house 16S rRNA gene sequencing. Overall, 502 different bacterial colonies from 346 urine samples taken from 324 inpatients were observed. The three quantitatively most abundant genera or genus clusters were Corynebacterium (254 isolates, 62%), Actinomyces/Winkia (79 isolates, 19%), and Actinotignum/Actinobaculum (29 isolates, 7%). Compared to sequencing, the diagnostic accuracy of all assessed competitor assays from the diagnostic routine was <80% for differentiation on the genus level and <30% for differentiation on the species level. Prolongated incubation for 4 days compared to 2 days resulted in additional detection of 15% of the totally recorded Gram-positive rod-shaped bacteria. An approximately 5-fold increased detection rate in mid-stream urine compared to urine acquired applying alternative sampling strategies was observed. In conclusion, in the rare event of the suspected clinical relevance of such findings, confirmatory testing with invasively sampled urine should be considered due to the high contamination rate observed in mid-stream urine. Confirmatory testing by DNA-sequencing methods should be considered if an exact identification of genus or species is regarded as relevant for the individual choice of the therapeutic strategy.

BACKGROUND: Reliable species identification of cultured isolates is essential in clinical bacteriology. We established a new study algorithm named NOVA - Novel Organism Verification and Analysis to systematically analyze bacterial isolates that cannot be characterized by conventional identification procedures MALDI-TOF MS and partial 16 S rRNA gene sequencing using Whole Genome Sequencing (WGS).
RESULTS: We identified a total of 35 bacterial strains that represent potentially novel species. Corynebacterium sp. (n = 6) and Schaalia sp. (n = 5) were the predominant genera. Two strains each were identified within the genera Anaerococcus, Clostridium, Desulfovibrio, and Peptoniphilus, and one new species was detected within Citrobacter, Dermabacter, Helcococcus, Lancefieldella, Neisseria, Ochrobactrum (Brucella), Paenibacillus, Pantoea, Porphyromonas, Pseudoclavibacter, Pseudomonas, Psychrobacter, Pusillimonas, Rothia, Sneathia, and Tessaracoccus. Twenty-seven of 35 strains were isolated from deep tissue specimens or blood cultures. Seven out of 35 isolated strains identified were clinically relevant. In addition, 26 bacterial strains that could only be identified at the species level using WGS analysis, were mainly organisms that have been identified/classified very recently.
CONCLUSIONS: Our new algorithm proved to be a powerful tool for detection and identification of novel bacterial organisms. Publicly available clinical and genomic data may help to better understand their clinical and ecological role. Our identification of 35 novel strains, 7 of which appear to be clinically relevant, shows the wide range of undescribed pathogens yet to define.

BACKGROUND: Norway spruce (Picea abies) resin-based products are used in human medicine. A resin-based otic rinse also could be useful in supportive care of canine otitis externa (COE), yet information on its antimicrobial effect against canine pathogens or ototoxicity is lacking.
OBJECTIVE: To investigate the antimicrobial properties and ototoxicity of a commercial resin-based otic product.
METHODS: Antimicrobial effect was evaluated using a standardised challenge test on Staphylococcus pseudintermedius, Corynebacterium auriscanis, Pseudomonas aeruginosa, Escherichia coli, Malassezia pachydermatis, and Streptococcus halichoeri strains to measure reduction in growth after 24 h exposure to the product. Effect on cell morphology was investigated by exposing S. pseudintermedius, C. auriscanis, P. aeruginosa and M. pachydermatis to the product in 20% and 100% (v/v) concentrations for 6, 24 and 48 h, and evaluating cells by transmission (TEM) and scanning (SEM) electron microscopy. An in vitro microbial kill-rate assay also was performed. Auditory brain stem response test, clinical evaluation and postmortem histological evaluation of ear canals were undertaken on experimental guinea pigs treated with the test product or saline controls.
RESULTS: The product showed >log 5 growth reduction for all strains in the challenge test. TEM and SEM images showed clear changes in the cells\' inner structures and deterioration of cells, and 100% (v/v) test product exposure induced microbial killing in 1-2 h. Ototoxicity was not detected in guinea pigs.
CONCLUSIONS: The product may be an option in supportive care of COE because of antimicrobial effects and lack of ototoxic properties in a guinea pig model.
UNASSIGNED: In der Humanmedizin werden Harz‐basierte Produkte der norwegischen Heckenfichte (Picea abies) eingesetzt. Ein Harz‐basierter Ohrreiniger könnte ebenfalls als unterstützende Behandlung bei der Otitis externa des Hundes (COE) nützlich sein, wobei Informationen über seine antimikrobielle Wirkung gegenüber Pathogenen des Hundes oder über eine eventuelle Ototoxizität fehlen.
UNASSIGNED: Ziel dieser Studie war es, die antimikrobiellen Eigenschaften und die Ototoxizität eines kommerziellen Harz‐basierten Ohrprodukts zu untersuchen.
UNASSIGNED: Die antimikrobielle Wirkung wurde mittels standardisiertem Provokationstest für Staphylococcus pseudintermedius, Corynebacterium auriscanis, Pseudomonas aeruginosa, Escherichia coli, Malassezia pachydermatis, und Streptococcus halichoeri Stämme erfasst, wobei nach 24 h mit dem Produkt eine Wachstumsminderung gemessen wurde. Die Auswirkung auf die Zellmorphologie wurde untersucht, wobei S. pseudintermedius, C. auriscanis, P. aeruginosa und M. pachydermatis dem Produkt bei einer Konzentration von 20% und 100% (v/v) 6, 24 und 48 h ausgesetzt wurden und danach die Zellen mittels Transmissions (TEM)‐ und Rasterelektronenmikroskop (SEM) beurteilt wurden. Ein in vitro Assay zur Erfassung der mikrobiellen Tötungsrate wurde ebenfalls durchgeführt. Ein Hirnstammaudiometrie Test, eine klinische Evaluierung und eine post mortem histologische Evaluierung der Ohrkanäle wurde bei Labormeerschweinchen durchgeführt, welche mit dem Testprodukt oder mit Kontrollen aus Kochsalzlösung behandelt worden waren.
UNASSIGNED: Das Produkt zeigte eine Wachstumsreduktion von >log 5 bei allen Stämmen im Provokationstest. TEM‐ und SEM‐Bilder zeigten deutliche Änderungen in den inneren Zellstrukturen und eine Entartung der Zellen, wobei der Kontakt mit dem Testprodukt zu 100% (v/v) die Mikroben innerhalb von 1‐2 h abtöteten. Bei den Meerschweinchen wurde keine Ototxizität festgestellt.
UNASSIGNED: In einem Meerschweinchen Modell könnte dieses Produkt bei der unterstützenden Behandlung einer COE aufgrund seiner antimikrobiellen Wirkung und den fehlenden ototoxischen Eigenschaften eine Option sein.
背景: 挪威云杉(Picea abies)树脂基产品用于人体医学。树脂基耳冲洗液也可用于犬外耳炎(COE)的支持性护理，但缺乏关于其对犬病原体抗菌性或耳毒性作用的信息。 目的: 研究一种市售树脂基耳产品的抗菌性能和耳毒性。 材料和方法: 使用标准化激发试验对假中间型葡萄球菌、犬耳道棒状杆菌、铜绿假单胞菌、大肠杆菌、厚皮马拉色菌和哈氏链球菌菌株进行抗菌效果评估，以测量暴露于该产品24小时后是否生长减少。通过将假中间型葡萄球菌、犬耳道棒状杆菌、铜绿假单胞菌和厚皮马拉色菌暴露于20%和100%(v/v)浓度的产品中6、24和48小时，并通过透射(TEM)和扫描(SEM)电子显微镜评估细胞，来研究对细胞形态的影响。还进行了体外微生物杀灭率测定。对用试验产品或生理盐水对照处理的实验豚鼠进行听脑干反应试验、耳道的临床评估和死后组织学评估。 结果: 在激发试验中，该产品显示所有菌株的生长减少>log5。TEM和SEM图像显示了细胞内部结构的明显变化和细胞的退化，100%(v/v)的测试产品暴露在1‐2小时内引起微生物被杀灭。在豚鼠中未检测到耳毒性。 结论和临床相关性: 该产品可能是COE支持性护理的一种选择，因为在豚鼠模型中具有抗菌作用且无耳毒性。.
BACKGROUND: Les produits à base de résine d\'épinette de Norvège (Picea abies) sont utilisés en médecine humaine. Un rinçage auiculaire à base de résine pourrait également être utile en tant qu’adjuvant des thérapeutiques de l\'otite externe canine (OEC), mais on manque d\'informations sur son effet antimicrobien contre les agents pathogènes canins ou sur son ototoxicité.
OBJECTIVE: Étudier les propriétés antimicrobiennes et l\'ototoxicité d\'un produit auriculaire commercial à base de résine. MATÉRIELS ET MÉTHODES: L\'effet antimicrobien est évalué par un test de croissance microbienne standardisé sur les souches Staphylococcus pseudintermedius, Corynebacterium auriscanis, Pseudomonas aeruginosa, Escherichia coli, Malassezia pachydermatis et Streptococcus halichoeri, afin de mesurer la réduction de la croissance après 24 heures d\'exposition au produit. L\'effet sur la morphologie des cellules est étudié en exposant S. pseudintermedius, C. auriscanis, P. aeruginosa et M. pachydermatis au produit à des concentrations de 20 % et 100 % (v/v) pendant 6, 24 et 48 heures, et en évaluant les cellules par microscopie électronique à transmission (TEM) et à balayage (SEM). Un test de bactéricidie in vitro est également réalisé. Un Potentiel Evoqué Auditif, des évaluations clinique et histologique post‐mortem des canaux auditifs sont effectués sur des cobayes expérimentaux traités avec le produit testé ou avec des contrôles salins. RÉSULTATS: Le produit permet une réduction de la croissance >log 5 pour toutes les souches lors du test de bactéricidie. Les images TEM et SEM montrent des changements évidents dans les structures internes des cellules et leur détérioration, et l\'exposition à 100% (v/v) du produit testé a induit la mort microbienne en 1‐2 h. Aucun phénomène d’ototoxicité n\'est détecté chez les cochons d\'Inde.
UNASSIGNED: Le produit peut être une option dans le traitement adjuvant des OEC en raison de ses effets antimicrobiens et de l\'absence d’ototoxicité dans un modèle expérimental de cobayes.
背景: 欧州唐檜 (Picea abies) 樹脂ベース製品は人間の医療に使用されている。 樹脂ベース耳洗浄剤は、犬の外耳炎(COE)の支持療法にも有用であると考えられるが、犬の病原体に対する抗菌効果や耳毒性に関する情報は不足している。 目的: 本研究の目的は、市販の樹脂ベース耳科製剤の抗菌特性と耳毒性を調査することであった。 材料と方法: Staphylococcus pseudintermedius、Corynebacterium auriscanis、Pseudomonas aeruginosa、Escherichia coli、Malassezia pachydermatis、Streptococcus halichoeriの各菌株を対象とした標準化負荷試験により抗菌効果を評価し、製品に24時間暴露した後の増殖の減少を測定した。細胞形態への影響は、S. pseudintermedius、C. auriscanis、P. aeruginosa、M. pachydermatisを20%および100%(v/v)濃度製品に6、24、48時間暴露し、透過型(TEM)および走査型(SEM)電子顕微鏡で細胞を評価することによって調査した。また、in vitro微生物死滅率アッセイも実施した。試験製品または対照として生理食塩水を投与した実験用モルモットを用いて、聴性脳幹反応試験、臨床評価、死後の外耳道組織学的評価を行った。 結果: 本製品は、負荷試験において、すべての菌株でlog 5以上の増殖抑制を示した。TEMおよびSEM画像は、細胞内部構造の明確な変化と細胞の劣化を示し、100%(v/v)の試験製品曝露は1~2時間で微生物の死滅を誘導した。 結論と臨床的意義: 本製品は、モルモットモデルにおいて抗菌効果があり、耳毒性もないことから、COEの支持療法における選択肢となりうる。.
UNASSIGNED: Produtos à base de resina de pinheiro norueguês (Picea abies) são utilizados na medicina humana. Uma solução otológica de limpeza à base de resina pode ser útil no tratamento da otite externa canina (COE), mas existem poucas informações sobre seu efeito antimicrobiano contra patógenos caninos ou sobre a sua ototoxicidade.
OBJECTIVE: Investigar as propriedades antimicrobianas e a ototoxicidade de um produto otológico comercial à base de resina. MATERIAIS E MÉTODOS: O efeito antimicrobiano foi avaliado usando um teste de provocação padronizado em cepas de Staphylococcus pseudintermedius, Corynebacterium auriscanis, Pseudomonas aeruginosa, Escherichia coli, Malassezia pachydermatis e Streptococcus halichoeri para mensurar a redução no crescimento após 24 horas de exposição ao produto. O efeito na morfologia celular foi investigado expondo S. pseudintermedius, C. auriscanis, P. aeruginosa e M. pachydermatis ao produto em concentrações de 20% e 100% (v/v) por 6, 24 e 48 h, e avaliando as células por microscopia eletrônica de transmissão (TEM) e varredura (SEM). Um ensaio in vitro de taxa de mortalidade microbiana também foi realizado. O teste de resposta auditiva do tronco encefálico, a avaliação clínica e a avaliação histológica post‐mortem dos condutos auditivos foram realizados em cobaias experimentais (porquinhos da índia) tratadas com o produto de teste ou controles salinos.
RESULTS: O produto apresentou redução de crescimento de >log 5 para todas as cepas no teste de provocação. As imagens TEM e SEM demonstraram mudanças claras nas estruturas internas das células e deterioração das mesmas, e 100% (v/v) de exposição ao produto de teste induziu morte microbiana em 1–2 h. Não foi detectada ototoxicidade nas cobaias experimentais. CONCLUSÕES E RELEVÂNCIA CLÍNICA: O produto pode ser uma opção no tratamento da COE devido aos efeitos antimicrobianos e à falta de propriedades ototóxicas em modelo de cobaia (porquinhos da índia).
INTRODUCCIÓN: Los productos a base de resina de pícea común (Picea abies) se utilizan en medicina humana. Un enjuague ótico a base de resina también podría ser útil como tratamiento de apoyo para la otitis externa canina (COE), aunque falta información sobre su efecto antimicrobiano contra los patógenos caninos o la ototoxicidad. OBJETIVOS: Investigar las propiedades antimicrobianas y la ototoxicidad de un producto ótico comercial a base de resina. MATERIALES Y MÉTODOS: El efecto antimicrobiano se evaluó mediante una prueba de exposición estandarizada en cepas de Staphylococcus pseudintermedius, Corynebacterium auriscanis, Pseudomonas aeruginosa, Escherichia coli, Malassezia pachydermatis y Streptococcus halichoeri para medir la reducción del crecimiento después de 24 h de exposición al producto. El efecto sobre la morfología celular se investigó exponiendo S. pseudintermedius, C. auriscanis, P. aeruginosa y p. pachydermatis al producto en concentraciones de 20 % y 100 % (v/v) durante 6, 24 y 48 h, y evaluando las células mediante microscopía electrónica de transmisión (TEM) y de barrido (SEM). También se realizó un ensayo de tasa de destrucción microbiana in vitro. Se realizaron pruebas de respuesta auditiva del tronco encefálico, evaluación clínica y evaluación histológica post mortem de los canales auditivos en conejillos de indias experimentales tratados con el producto de prueba o controles de solución salina. RESULTADOS: El producto mostró una reducción del crecimiento >log 5 para todas las cepas en la prueba de exposición. Las imágenes TEM y SEM mostraron cambios claros en las estructuras internas de las células y el deterioro de las células, y la exposición al 100% (v/v) del producto de prueba indujo la muerte microbiana en 1 a 2 h. No se detectó ototoxicidad en cobayas. CONCLUSIONES Y RELEVANCIA CLÍNICA: El producto puede ser una opción en el cuidado de apoyo de COE debido a los efectos antimicrobianos y la ausencia de otototoxicidad en un modelo experimental en cobayas.

UNASSIGNED: To investigate Corynebacterium striatum as a nosocomial pathogen infecting hard-to-heal peripheral wounds, such as skin wounds, soft tissue abscesses and osteomyelitis. As of 2023, the medical community were alerted against the risk of emerging systemic and central infections; on the other hand literature on peripheral cutaneous regions is still scarce.
UNASSIGNED: In this study, two groups of patients with similar lesions which were infected were compared: one group with the presence of the coryneform rod, the other without.
UNASSIGNED: In total, Corynebacterium striatum was cultured from 62 patients and 131 samples. Corynebacterium striatum infection correlated well with the presence of: foot ulcer; venous leg ulcer; altered ambulation and/or altered foot loading; peripheral vascular and arterial disease; hospitalisation; malignancy; spinal cord injury; and recent administration of antibiotics (p<0.05 for all associations). Patients with Corynebacterium striatum had a lower overall survival rate compared to patients in the non-Corynebacterium striatum group (28.6 versus 31.6 months, respectively; p=0.0285). Multivariate analysis revealed that Corynebacterium striatum infection was an independent factor for poor prognosis (p<0.0001).
UNASSIGNED: In view of the findings of our study, Corynebacterium striatum appears to be an important opportunistic pathogen infecting peripheral tissues and complicating wound healing. Given its numerous and worrying virulence factors (such as multidrug resistance and biofilm production), particular attention should be given to this pathogen by professional wound care providers in nosocomial and outpatient environments.

Skin is a diverse ecosystem that provides a habitat for microorganisms. The skin condition and the skin microbiome interact each other under diverse environmental conditions. This study was conducted on 10 study participants for a one-year, from September 2020 to August 2021, to investigate the variability of skin microbiome and skin biophysical parameters [TEWL, hydration, and elasticity (R5)] according to season, and to understand the interplay between skin microbiome and skin characteristics. We identified that Cutibacterium, Corynebacterium, Staphyloccocus, unclassified genus within Neisseriaceae, and Streptococcus were major skin microbial taxa at the genus level, and fluctuated with the seasons. Cutibacterium was more abundant in winter, while Corynebacterium, Staphylococcus, and Streptococcus were more abundant in summer. Notably, Cutibacterium and skin barrier parameter, TEWL, exhibited a co-decreasing pattern from winter to summer and showed a significant association between Cutibacterium and TEWL. Furthermore, functional profiling using KEGG provided clues on the impact of Cutibacterium on the host skin barrier. This study enhances our understanding of the skin microbiome and its interplay with skin characteristics and highlights the importance of seasonal dynamics in shaping skin microbial composition.

In July, 2022, an increase in diphtheria cases caused by toxigenic Corynebacterium diphtheriae (C diphtheriae) was reported among asylum seekers arriving by small boats to England. Rising case numbers presented challenges for case and contact management in initial reception centres, prompting changes to national guidance and implementation of population-based control measures. This study aimed to describe the outbreak of toxigenic C diphtheriae among asylum seekers arriving by small boats to England during 2022 by use of national surveillance data.
We undertook a descriptive epidemiological analysis of cases of toxigenic C diphtheriae among asylum seekers arriving by small boats to England during 2022, incorporating genomic sequencing data, antibiotic susceptibility testing results, and epidemiological data obtained through the UK Health Security Agency\'s national enhanced surveillance programme. Health Protection Teams conducted risk assessments, and operational data (including details regarding offer and uptake of antibiotics and vaccinations) were obtained from National Health Service partners supporting the intervention programme.
In 2022, C diphtheriae isolates from 86 asylum seekers arriving by small boats were submitted to the National Reference Laboratory for confirmation and testing. Toxigenic C diphtheriae was confirmed for 72 (84%) cases and one individual with typical diphtheritic lesions but from whom no C diphtheriae was isolated from clinical swabs was also included as a probable case, resulting in 73 cases of diphtheria. 71 (97%) were male, 39 (53%) were younger than 18 years, and 36 (49%) presented with cutaneous diphtheria. The prevalence of diphtheria was highest among Afghans (1·3%) compared with all other nationalities (<0·1%). Local antibiotic susceptibility testing identified six cases with a macrolide resistant strain.
The increase in diphtheria coincided with a high volume of asylum seekers arriving by small boats to England during 2022, and subsequently increased clinical awareness of the disease among this population. Long-term disruption to vaccination programmes in origin countries along with barriers to accessing health care along migrant routes puts asylum seekers arriving by small boats at risk of disease. With arrivals expected to continue in 2023, the UK Health Security Agency has recommended continuation of population-based control measures in England until October, 2023, subject to ongoing review.
The UK Health Security Agency.

BACKGROUND: Pseudomembranous cystitis (PMC) in cats is a recognized disease, but concurrent mineralization is reported rarely and its outcome is poorly described.
OBJECTIVE: Describe a population of cats with PMC and the prevalence of concurrent mineralization.
METHODS: Twenty-six cats with PMC.
METHODS: Medical records were retrospectively reviewed (January 2016 to December 2021). Cats with an ultrasound diagnosis of PMC were included. Clinicopathologic results, imaging, treatment, and outcome were reviewed.
RESULTS: All cats were male and 21 (80%) were diagnosed with urethral obstruction (UO). Five cats (23.8%) had positive urine culture (Staphylococcus felis, 3/5; Proteus mirabilis, 2/5) with a median urine pH of 8 (range, 6-9). All cats had ultrasonographic changes suggestive of mineralization. On ultrasound examination, 10 cats (38.5%) had pseudomembranes with acoustic shadowing suggestive of mineralization, 15 (57.7%) had changes indicative of ulceration, and 8 (31%) had changes compatible with of a urachal anomaly. Twenty-two cats received medical treatment, 4 underwent surgery (3 percutaneous cystolithotomy, 1 cystotomy). Twenty cats (77%) survived to discharge. Follow-up ultrasound examination indicated resolution of PMC in 6/7 cats, 4 had persistent hyperechoic bladder lining. Five of 12 cats with follow-up had a relapse of lower urinary tract signs.
CONCLUSIONS: Pseudomembranous cystitis was diagnosed mainly in male cats with UO and imaging findings suggestive of mineralization were present in all cases. Frequent negative urine culture suggests a different etiology than encrusting cystitis related to urease-positive bacteria. Good outcomes can be achieved with medical management.

Increasing evidence has suggested that Corynebacterium kroppenstedtii is associated with some cases of granulomatous mastitis, mostly based on pathology or microbiology. We aimed to identify the clinical characteristics and treatment regimens for granulomatous mastitis with Corynebacterium kroppenstedtii infection. Understanding these clinical features is essential for patient care.
We retrospectively collected data on 201 patients who were pathologically diagnosed with granulomatous mastitis and had microbiological results of either Corynebacterium kroppenstedtii or no bacterial growth and recorded and analysed their demographics, clinical characteristics, and clinical outcomes.
There were 107 patients in the CK group and 94 patients in the negative group. Sinus formation (x2 = 13.028, p = 0.000), time to complete remission at the first treatment period (Z = -3.027, p = 0.002), diameter of breast mass at first-time medical consultancy (Z = -2.539, p = 0.011) and recurrence (x2 = 4.953, p = 0.026) were statistically significant. Age (Z = -1.046, p = 0.295), laterality (x2 = 4.217, p = 0.121), time to presentation since the last delivery (x2 = 0.028, p = 0.868), BMI (Z = -0.947, p = 0.344), lactation time (Z = -1.378, p = 0.168), parity (x2 = 1.799, p = 0.180), gravida (Z = -0.144, p = 0.885), history of lactational mastitis or abscess (x2 = 0.115, p = 0.734), local trauma (x2 = 0.982, p = 0.322), hyperprolactinemia (x2 = 0.706, p = 0.401), erythema nodosum (x2 = 0.292, p = 0.589), and nipple discharge (x2 = 0.281, p = 0.596) did not demonstrate statistical significance. Regarding recurrence related to therapeutic strategy, except for surgery combined with immunosuppressants (x2 = 9.110, p = 0.003), which was statistically significant, none of the other treatment regimens reached statistical significance. The recurrence rate of patients in the CK group using rifampicin in their treatment course was 22.0% (x2 = 4.892, p = 0.027).
Granulomatous mastitis accompanied by Corynebacterium kroppenstedtii more easily forms sinuses and has a higher recurrence rate. Both of the clinical characteristics may indicate that Corynebacterium kroppenstedtii plays an important role in the development and progression of granulomatous mastitis. Lipophilic antibiotics may be essential for granulomatous mastitis with Corynebacterium kroppenstedtii infection.

Corynebacterium spp. are associated with respiratory infections in immunocompromised hosts. A link with bronchial complications after lung transplantation (LTx) has been suggested. We aimed to assess the link between respiratory sampling of Corynebacterium spp. and significant bronchial complication (SBC) after LTx. We performed a single center retrospective study. Inclusion of LTx recipients with at least one respiratory Corynebacterium spp. sample (July 2014 to December 2018). Subjects were matched to unexposed LTx recipients. Primary outcome was SBC occurrence after Corynebacterium spp. isolation. Secondary outcomes were Corynebacterium spp. persistent sampling, chronic lung allograft dysfunction (CLAD) onset and all-cause mortality. Fifty-nine patients with Corynebacterium spp. sampling with 59 without isolation were included. Corynebacterium spp. identification was not associated with SBC occurrence (32.4% vs. 21.6%, p = 0.342). Previous SBC was associated with further isolation of Corynebacterium spp. (OR 3.94, 95% CI [1.72-9.05]). Previous SBC and corticosteroids pulses in the last 3 months were the only factors associated with increased risk of Corynebacterium spp. isolation in multivariate analysis. Corynebacterium spp. sampling was significantly associated with CLAD onset (27.1% vs. 6.9%, p = 0.021). Corynebacterium spp. isolation was not associated with SBC but with higher risk of CLAD. Whether CLAD evolution is affected by Corynebacterium spp. eradication remains to be investigated.

BACKGROUND: The culture method is the gold standard for identifying pathogenic bacteria in patients with pneumonia but often does not reflect the exact bacterial flora in pulmonary lesions of pneumonia, partly owing to easiness or difficulties in culturing certain bacterial species. We aimed to evaluate bacterial flora in bronchoalveolar lavage fluid (BALF) samples directly obtained from pneumonia lesions using 16S ribosomal RNA (rRNA) gene analysis to compare the results of the BALF culture method in each category of pneumonia.
METHODS: Bacterial florae were detected by a combination of the culture method, and the clone library method using the 16S rRNA gene sequencing in BALF directly obtained from pneumonia lesions in pneumonia patients from April 2010 to March 2020 at the University of Occupational and Environmental Health, Japan, and affiliated hospitals. Clinical information of these patients was also collected, and lung microbiome was evaluated for each pneumonia category.
RESULTS: Among 294 pneumonia patients (120 with community-acquired pneumonia (CAP), 101 with healthcare-associated pneumonia (HCAP), and 73 with hospital-acquired pneumonia (HAP)), significantly higher percentages of obligate anaerobes were detected in CAP than in HCAP and HAP patients by the clone library method. Corynebacterium species were significantly highly detected in HAP patients and patients with cerebrovascular diseases than in patients without, and Streptococcus pneumoniae was frequently detected in patients with diabetes mellitus.
CONCLUSIONS: Obligate anaerobes may be underestimated in patients with CAP. Corynebacterium species should be regarded as the causative bacteria for pneumonia in patients with HAP and cerebrovascular diseases.