Gut Microbiota Composition in Prediabetes and Newly Diagnosed Type 2 Diabetes: A Systematic Review of Observational Studies.

Evidence of gut microbiota involvement in regulating glucose metabolism and type 2 diabetes mellitus (T2DM) progression is accumulating. The understanding of microbial dysbiosis and specific alterations of gut microbiota composition that occur during the early stages of glucose intolerance, unperturbed by anti-diabetic medications, is especially essential. Hence, this systematic review was conducted to summarise the existing evidence related to microbiota composition and diversity in individuals with prediabetes (preDM) and individuals newly diagnosed with T2DM (newDM) in comparison to individuals with normal glucose tolerance (nonDM). A systematic search of the PubMed, MEDLINE and CINAHL databases were conducted from inception to February 2021 supplemented with manual searches of the list of references. The primary keywords of "type 2 diabetes", "prediabetes", "newly-diagnosed" and "gut microbiota" were used. Observational studies that conducted analysis of the gut microbiota of respondents with preDM and newDM were included. The quality of the studies was assessed using the modified Newcastle-Ottawa scale by independent reviewers. A total of 18 studies (5,489 participants) were included. Low gut microbial diversity was generally observed in preDM and newDM when compared to nonDM. Differences in gut microbiota composition between the disease groups and nonDM were inconsistent across the included studies. Four out of the 18 studies found increased abundance of phylum Firmicutes along with decreased abundance of Bacteroidetes in newDM. At the genus/species levels, decreased abundance of Faecalibacterium prausnitzii, Roseburia, Dialister, Flavonifractor, Alistipes, Haemophilus and Akkermansia muciniphila and increased abundance of Lactobacillus, Streptococcus, Escherichia, Veillonella and Collinsella were observed in the disease groups in at least two studies. Lactobacillus was also found to positively correlate with fasting plasma glucose (FPG), HbA1c and/or homeostatic assessment of insulin resistance (HOMA-IR) in four studies. This renders a need for further investigations on the species/strain-specific role of endogenously present Lactobacillus in glucose regulation mechanism and T2DM disease progression. Differences in dietary intake caused significant variation in specific bacterial abundances. More studies are needed to establish more consistent associations, between clinical biomarkers or dietary intake and specific gut bacterial composition in prediabetes and early T2DM.

Gut bacteria characteristic of the infant microbiota down-regulate inflammatory transcriptional responses in HT-29 cells.

Immuno-modulatory effects of infant gut bacteria were tested on poly(I:C) stimulated HT-29 intestinal epithelial cells. Blautia producta, Bacteroides vulgatus, Bacteroides fragilis and Bacteroides thetaiotaomicron decreased transcription of poly(I:C)-induced inflammatory genes. Modulation of basal level and poly(I:C)-induced IL-8 secretion varied between bacterial species, and between heat treated and non-heat treated bacterial cells.

Distribution and Antifungal Susceptibility Pattern of Candida species at a Tertiary Hospital in Malaysia.

INTRODUCTION: Invasive Candida infections cause significant mortality and morbidity worldwide. Information on recent trends in species distribution and antifungal resistance in local settings is essential. METHODOLOGY: Yeast isolates identified through standard culture methods throughout 2014 and 2015 from Hospital Ampang, Malaysia were retrospectively studied. The antifungal susceptibility of Candida species was determined using colorimetric broth microdilution method and MIC values interpreted according to CLSI breakpoints. RESULTS: Out of all the 149 yeast cultures collected, most were from blood (55.7%) and respiratory specimens (33.6%). Candida tropicalis was the most common (28.9%), followed by C. albicans (26.2%), C. parapsilosis (15.4%), C. glabrata (14.1%), Crytococcus neoformans (6.7%), Trichosporon asahi (3.4%), C. krusei (2.0%), C. famata, C. rugose, C. guilliermondii, C. dublinensis and Trichosporon spp. (0.7% each). Occurrence of C. tropicalis in candidaemia cases was significantly associated to presence of an underlying haematological disorder, while C. albicans isolates in blood were significantly found in absence of such disorders. The four most common Candida species isolated showed high susceptibility to amphotericin B (100%), anidulafungin (100%), micafungin (100%), caspofungin (98.4%), flucytosine (98.4%) and voriconazole (84.1%). However, drug susceptibility to itraconazole and fluconazole was comparatively lower (57.9% and 72.2%, respectively). C. glabrata and C. tropicalis were the least susceptible to these azoles. CONCLUSION: Prevalence of the high number of non-albicans Candida species with slight predominance of C. tropicalis over C. albicans was observed. Low susceptibility to itraconazole among C. glabrata and C. tropicalis isolates and to fluconazole among C. glabrata isolates warrants for continued surveillance to monitor emerging antifungal resistance.

Antimicrobial susceptibility of clinical isolates of Pseudomonas aeruginosa from a Malaysian Hospital.

Ongoing surveillance of Pseudomonas aeruginosa resistance against antimicrobial agents is fundamental to monitor trends in susceptibility patterns and to appropriately guide clinicians in choosing empirical or directed therapy. The in vitro activity level of eight antimicrobial drugs was assessed against 97 clinical isolates of P. aeruginosa collected consecutively for three months in 2007 from a Malaysian hospital. Antimicrobial susceptibility was determined using the E-test method in addition to the hospital's routine diagnostic testing by the disk diffusion method. Respiratory and wound swab isolates were the most frequently encountered isolates. The E-test and disk diffusion methods showed high concordance in determining the in vitro activity of the antimicrobial agents against the E isolates. Piperacillin-tazobactam was the most active antimicrobial agent with 91.8% susceptibility, followed by the aminoglycosides (amikacin, 86.6% and gentamicin, 84.5%), the quinolone (ciprofloxacin, 83.5%) and the beta-lactams (cefepime, 80.4%, ceftazidime, 80.4%, imipenem, 79.4% and meropenem, 77.3%). Incidence of multidrug resistance was 19.6% (19 out of 97 isolates). Periodic antibiotic resistance surveillance is fundamental to monitor changes in susceptibility patterns in a hospital setting.