Shorter time-to-positivity and turnaround time with mycosis blood culture bottles when detecting Candida albicans.
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ABSTRACT:
SUBMITTER: Farber J
PROVIDER: S-EPMC10955001 | biostudies-literature | 2024 Apr
REPOSITORIES: biostudies-literature
Publications
Shorter time-to-positivity and turnaround time with mycosis blood culture bottles when detecting Candida albicans.
Färber Jacqueline J Kaasch Achim J AJ Schalk Enrico E
Infection 20240223 2
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Project description:BackgroundMycobacterial time to positivity (TTP) in liquid culture media has predictive value for longer term outcomes in pulmonary tuberculosis, but has not been thoroughly studied in nontuberculous mycobacterial pulmonary disease. This study sought to evaluate for association between TTP and sputum culture conversion to negative in pulmonary disease caused by Mycobacterium avium complex (MAC).MethodsData from the CONVERT trial (NCT02344004) that evaluated efficacy of guideline-based-therapy with or without amikacin liposome inhalation suspension in adults with refractory MAC-PD (Mycobacterium avium complex pulmonary disease) were analyzed. We evaluated TTP measures for sputum obtained prior to study treatment initiation and at monthly visits, assessing reproducibility of measures as well as association of TTP with culture conversion on treatment.ResultsData from 71 participants with at least one screening visit TTP value were analyzed. For participants who provided more than one sputum sample at a given visit, there was moderate between-sample reliability, with median intraclass correlation coefficient 0.62 (IQR 0.50, 0.70). Median TTP at screening was longer in those participants who subsequently achieved vs. did not achieve culture conversion (10.5 [IQR 9.4] days vs. 4.2 [IQR 2.8] days, p = 0.0002). Individuals with culture conversion by study treatment month 6 were more likely to have a screening TTP > 5 days compared to those who did not achieve culture conversion (OR 15.4, 95% CI 1.9, 716.7, p = 0.0037) and had increasing TTPs over time.ConclusionsTTP prior to and on treatment is associated with microbiological treatment response in patients with MAC-PD.
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Project description:The rapid identification of blood culture isolates and antimicrobial susceptibility test (AST) results play critical roles for the optimal treatment of patients with bloodstream infections. Whereas others have looked at the time to detection in automated culture systems, we examined the overall time from specimen collection to actionable test results. We examined four points of time, namely, blood specimen collection, Gram stain, organism identification (ID), and AST reports, from electronic data from 13 U.S. hospitals for the 11 most common, clinically significant organisms in septic patients. We compared the differences in turnaround times and the times from when specimens were collected and the results were reported in the 24-h spectrum. From January 2015 to June 2016, 165,593 blood specimens were collected, of which, 9.5% gave positive cultures. No matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry was used during the study period. Across the 10 common bacterial isolates (n = 6,412), the overall median (interquartile range) turnaround times were 0.80 (0.64 to 1.08), 1.81 (1.34 to 2.46), and 2.71 (2.46 to 2.99) days for Gram stain, organism ID, and AST, respectively. For all positive cultures, approximately 25% of the specimens were collected between 6:00 a.m. and 11:59 a.m. In contrast, more of the laboratory reporting times were concentrated between 6:00 a.m. and 11:59 a.m. for Gram stain (43%), organism ID (78%), and AST (82%), respectively (P < 0.001). The overall average turnaround times from specimen collection for Gram stain, organism ID, and AST were approximately 1, 2, and 3 days, respectively. The laboratory results were reported predominantly in the morning hours. Laboratory automation and work flow optimization may play important roles in reducing the microbiology result turnaround time.
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Project description:LC-MS/MS approach was utilized to identify qualitative changes in protein expressed by planktonic and biofilm cells of C. albicans.
2021-02-25 | PXD007831 | Pride
Project description:Candida spp. are commensal opportunistic fungal pathogens that often colonize and infect mucosal surfaces of the human body. Candida, along with other microbes in the microbiota, generally grow as biofilms in a polymicrobial environment. Due to the nature of cellular growth in a biofilm (such as production of a protective extracellular matrix) and the recalcitrance of biofilms, infections involving biofilms are very difficult to treat with antibiotics and perpetuate the cycle of infection. The two most commonly isolated Candida spp. from Candida infections are Candida albicans and Candida glabrata, and the presence of both of these species results in increased patient inflammation and overall biofilm formation. This work aims to investigate the interspecies interactions between C. albicans (Ca) and C. glabrata (Cg) in co-culture through transcriptome analysis over the course of biofilm growth. We report that during co-culture, lipid biosynthesis and transporter genes were significantly modulated in both Ca and Cg. Differentially expressed genes in Ca during co-culture growth included putative transporter genes (C2_02180W_A and C1_09210C_B; up-regulated), amino acid biosynthesis (ARO7; up-regulated most in Ca:Cg 1:3), and lipid-related genes (LIP3 and IPT1; down-regulated). Differentially expressed genes in Cg in co-culture included putative transmembrane transporters (CAGL0H03399g and CAGL0K04609g; up-regulated), an oxidative stress response gene (CAGL0E04114g; down-regulated most in Ca:Cg 1:3), genes involved in the TCA cycle (LYS12 and CAGL0J06402g; down-regulated), and several genes involved in cell wall/membrane biosynthesis (SEC53, GAS2, VIG9; down-regulated). Additionally, confocal microscopy was utilized for membrane lipid analysis between monoculture and co-culture biofilms. Through filipin-stained lipid analysis, we found that there was a significant increase in cell membrane lipid content in Ca:Cg 1:3 biofilms compared to Ca and Ca:Cg 3:1 biofilms. These results suggest substantial modifications of both cell wall, cell membrane, and transporters in both Ca and Cg during the time course of co-culture growth, which allows for increased biofilm formation and virulence in Candida co-culture biofilms.
2019-05-31 | GSE119059 | GEO
Project description:Time to blood culture positivity (TTP) is an indirect measure of bacterial concentration in blood. A short TTP has been linked to the presence of infective endocarditis (IE) and to poor prognosis in Staphylococcus aureus bacteremia. We analyze factors influencing TTP in bacteremia with Enterococcus faecalis. This retrospective observational study of medical records included adults diagnosed with monomicrobial E. faecalis bacteremia between 2015 and 2018 in the Skåne region (Sweden). For each episode, the shortest TTP was recorded. Median TTP was compared between patients grouped based on age, sex, comorbidity, site of acquisition, and focus of infection. Using a dichotomized TTP (shorter or longer than 12 h), a multivariable logistic regression for factors associated to TTP was performed. The association between TTP and IE or mortality was evaluated. Three hundred sixty-seven episodes with monomicrobial E. faecalis bacteremia with the corresponding TTP were identified. Median TTP for the entire cohort was 11.6 (IQR 9.9-14.1) h and a significantly shorter TTP was noted for episodes which represented IE (n = 55, 9.4 (IQR 6.4-10.6) h). Only IE remained associated with a short TTP (≤ 12 h) in binary logistic regression analysis. Factors associated with IE were investigated and TTP was associated with IE also when adjusted for age, gender, comorbidity, and nosocomial acquisition. There was no association between TTP and mortality. A low TTP is associated with IE in E. faecalis bacteremia and could be used as a help in determining the need for echocardiography in patients with this condition.
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