Quantitative PCR Effectively Quantifies Triazole-Susceptible and Triazole-Resistant in Mixed Infections.

Increasing resistance to triazole antifungals in is worrisome because of the associated high mortality of triazole-resistant (TRAF) infections. While most studies have focused on single triazole-susceptible (WT) or TRAF infections, reports of TRAF cases developing mixed WT and TRAF infections have been described in several studies. However, the prevalence of mixed infections and their responses to current recommended therapies are unknown and could be inappropriate, leading to poor clinical outcomes.

Stable prevalence of triazole-resistance in Aspergillus fumigatus complex clinical isolates in a Belgian tertiary care center from 2016 to 2020.

Background: Prevalence reports of triazole-resistance in Aspergillus fumigatus differ between countries and centers and may likewise vary over time. Continuous local surveillance programs to establish the evolving epidemiology of triazole-resistance in A. fumigatus are crucial to guide therapeutic recommendations.

Triazole-Resistance in Environmental in Latin American and African Countries.

Triazole-resistance has been reported increasingly in . An international expert team proposed to avoid triazole monotherapy for the initial treatment of invasive aspergillosis in regions with >10% environmental-resistance, but this prevalence is largely unknown for most American and African countries. Here, we screened 584 environmental samples (soil) from urban and rural locations in Mexico, Paraguay, and Peru in Latin America and Benin and Nigeria in Africa for triazole-resistant .

Gene Mutation Prevalence in Triazole-Resistant Clinical Isolates.

Recently, mutations in the -encoding gene (), a gene involved in ergosterol production, were associated with triazole-resistance in . In this study, we determined the prevalence and characteristics of mutations in a collection of clinical triazole-resistant isolates collected during 2001-2019 from two international mycology reference centers: the Belgian National Reference Center for Mycosis and the Center of Expertise in Mycology Radboudumc/CWZ. Clinical isolates with and without gene mutations and randomly selected wild-type (WT) controls were included.

The Possible Role of Staphylococcus epidermidis LPxTG Surface Protein SesC in Biofilm Formation.

Staphylococcus epidermidis is the most common cause of device-associated infections. It has been shown that active and passive immunization in an animal model against protein SesC significantly reduces S. epidermidis biofilm-associated infections.

Inhibition of Staphylococcus epidermidis biofilm formation by rabbit polyclonal antibodies against the SesC protein.

Several well-studied proteins with defined roles in Staphylococcus epidermidis biofilm formation are LPXTG motif-containing proteins. Here, we investigate the possible use of the LPXTG motif-containing protein SesC (S. epidermidis surface protein C; accession no.

The role of sigmaB in persistence of Staphylococcus epidermidis foreign body infection.

Staphylococcal biofilm formation depends on the transcription factor sigma(B). We further investigated the role of sigma(B) in biofilm formation and persistence in vitro and in vivo in a subcutaneous rat model. As expected, expression of all sigma(B) operon genes was transiently higher in the first 6 h of biofilm formation compared to planktonic bacteria, concurrent with a temporary upregulation of icaA and aap expression.

Effect of iron on the expression of sirR and sitABC in biofilm-associated Staphylococcus epidermidis.

Background: Different gene expression patterns correlate with the altered phenotype in biofilm-associated bacteria. Iron and iron-linked genes are thought to play a key-role in biofilm formation. The expression of Fe-linked genes (sirR, sitABC operon) in Staphylococcus epidermidis, was compared in planktonic versus sessile bacteria in vitro and in vivo in a subcutaneous foreign body rat model.

The effect of systemic antibiotics on the microbiological diagnosis of experimental foreign body infections caused by Staphylococcus epidermidis.

Qualitative broth culture and quantitative culture on agar were compared with quantitative polymerase chain reaction (PCR) for the diagnosis of foreign body infections (FBI) in a rat model with and without exposure to systemic antibiotics (teicoplanin and rifampin). The 3 methods had a similar and high yield without antibiotics. Antibiotics decreased the number of CFU/foreign body and increased the number of culture-negative foreign bodies and the variability of the results in quantitative culture.

Expression of biofilm-associated genes in Staphylococcus epidermidis during in vitro and in vivo foreign body infections.

The expression of the genes icaA, icaC, aap, and atlE--with a putative role in the pathogenesis of Staphylococcus epidermidis foreign body infections--and of mecA and 3 housekeeping genes (gmk, tpi, and hsp60) was examined in vitro and in vivo. In vitro expression levels of ica, atlE, and gmk were higher in sessile than in planktonic bacteria. Exposure to foreign bodies in vitro and in vivo induced a sharp increase in ica expression that was followed by a progressive decrease.