Relationship between skin fungal and bacterial microbiomes and skin pH.

OBJECTIVE: The present study investigated the relationship between the skin bacterial and fungal microbiomes and skin pH at sebaceous sites, namely, the forehead, cheek and upper chest. We also examined the relationship between the skin microbiome and transepidermal water loss (TEWL), which is an indicator of rough skin. METHODS: Thirty healthy Japanese subjects (15 females and 15 males) were enrolled as subjects. The forehead, cheek and upper chest were examined in August (summer) and February (winter). Skin surface samples were collected using the swab method, and the 16s rRNA and ITS regions were analysed using next-generation sequencing. Skin pH and TEWL were also assessed. RESULTS: The changes observed in the skin microbiome were associated with season-dependent changes in skin pH. An increase in skin pH at the forehead and cheek was associated with a higher relative abundance of Cutibacterium spp., a reduction in bacterial diversity, and a lower relative abundance of Staphylococcus spp. A decrease in skin pH at the upper chest was associated with a higher relative abundance of Malassezia restricta, a lower relative abundance of M. sympodialis and decrease in fungal diversity. Moreover, these changes were also associated with an increase in TEWL. CONCLUSION: The present results indicate that changes in skin pH are associated with changes in the skin bacterial and fungal microbiomes at sebaceous sites. The changes observed in the skin microbiome were also associated with rough skin.

OBJECTIF: La présente étude a examiné la relation entre les microbiomes bactériens et fongiques de la peau et le pH de la peau des sites sébacés, à savoir le front, la joue et la partie supérieure du thorax. Nous avons également examiné la relation entre le microbiome cutané et la perte d'eau transépidermique (transepidermal water loss, TEWL), qui est un indice de rugosité cutanée. MÉTHODES: Trente sujets japonais en bonne santé (15 femmes et 15 hommes) ont été inclus en tant que sujets de l'étude. Le front, la joue et la partie supérieure du thorax ont été examinés en août (été) et en février (hiver). Des échantillons de surface cutanée ont été prélevés par écouvillonnage et les régions de l'ARNr 16s et ITS ont été analysées par séquençage à haut débit. Le pH de la peau et la TEWL ont également été évalués. RÉSULTATS: Les changements observés dans le microbiome cutané étaient associés à des modifications du pH de la peau dépendant de la saison. Une augmentation du pH de la peau au niveau du front et de la joue était associée à une plus grande abondance relative de Cutibacterium spp. et à une réduction de la diversité bactérienne, ainsi qu'à une plus faible abondance relative de Staphylococcus spp. Une diminution du pH de la peau au niveau de la partie supérieure du thorax était associée à une abondance relative plus élevée de Malassezia restricta et à une abondance relative plus faible de M. sympodialis, ainsi qu'à une diversité fongique. De plus, ces changements ont également été associés à une augmentation de la TEWL. CONCLUSION: Ces résultats indiquent que les modifications du pH de la peau sont associées à des modifications des microbiomes bactérien et fongique de la peau au niveau des sites sébacés. Les changements observés dans le microbiome de la peau étaient également associés à une rugosité de la peau.

PCR-based ORF typing of Klebsiella pneumoniae for rapid identification of global clones and transmission events.

AIMS: Klebsiella pneumoniae is a major cause of healthcare-associated infections. In this study, we aimed to develop a rapid and simple genotyping method that can characterize strains causing nosocomial infections. METHODS AND RESULTS: The PCR-based open reading frame (ORF) typing (POT) method consists of two multiplex PCR reactions that were designed to detect 25 ORFs specific to bacterial genetic lineages, species, antimicrobial-resistant genes (blaCTX-M group-1 , blaCTX-M group-9 , blaIMP and blaKPC ), a capsular K1-specific gene and a virulence factor gene (rmpA/A2). The electrophoresis results are then digitized. A total of 192 strains (136 clinical and 8 reference strains of K. pneumoniae, 33 clinical and 1 reference strains of K. variicola and 14 clinical strains of K. quasipneumoniae) were classified into 95, 26 and 11 POT values, respectively. The distribution patterns of ORFs among K. pneumoniae correlated well with multilocus sequence typing (MLST). Furthermore, closely related species could be distinguished and key antimicrobial resistance and hypervirulence genes were identified as part of POT. CONCLUSIONS: The POT method was developed and validated for K. pneumoniae. In comparison to MLST, the POT method is a rapid and easy genotyping method for monitoring transmission events by K. pneumoniae in clinical microbiology laboratories. SIGNIFICANCE AND IMPACT OF THE STUDY: The POT method supplies clear and informative molecular typing results for K. pneumoniae. The method would facilitate molecular epidemiological analysis in infection control and hospital epidemiology investigations.

Fatal fulminant community-acquired pneumonia caused by hypervirulent Klebsiella pneumoniae K2-ST86: Case report.

RATIONALE: Invasive community-acquired infections, including pyogenic liver abscesses, caused by hypervirulent Klebsiella pneumoniae (hvKp) strains have been well recognized worldwide. Among these, sporadic hvKp-related community-acquired pneumonia (CAP) is an acute-onset, rapidly progressing disease that can likely turn fatal, if left untreated. However, the clinical diagnosis of hvKp infection remains challenging due to its non-specific symptoms, lack of awareness regarding this disease, and no consensus definition of hvKp. PATIENT CONCERNS: A 39-year-old man presented with high-grade fever and sudden-onset chest pain. Laboratory testing revealed an elevated white blood cell count of 11,600 cells/µl and C-reactive protein level (>32 mg/dl). A chest X-ray and computed tomography revealed a focal consolidation in the left lower lung field. DIAGNOSIS: Diagnosis of fulminant CAP caused by a hvKp K2-ST86 strain was made based upon multilocus sequencing typing (MLST). INTERVENTIONS: The patient was treated with ampicillin/sulbactam. OUTCOMES: The pneumonia became fulminant. Despite intensive care and treatment, he eventually died 15.5 hours after admission. LESSONS: This is the first case of fatal fulminant CAP caused by a hvKp K2-ST86 strain reported in Japan. MLST was extremely useful for providing a definitive diagnosis for this infection. Thus, we propose that a biomarker-based approach should be considered even for an exploratory diagnosis of CAP related to hvKp infection.