Antimicrobial susceptibility among Gram-positive and Gram-negative organisms collected from the Latin American region between 2004 and 2015 as part of the Tigecycline Evaluation and Surveillance Trial.

BACKGROUND: The in vitro activity of tigecycline and comparator agents was evaluated against Gram-positive and Gram-negative isolates collected in Latin American centers between 2004 and 2015 as part of the Tigecycline Evaluation and Surveillance Trial (T.E.S.T.) global surveillance study. METHODS: Minimum inhibitory concentrations (MICs) were determined using the broth microdilution methodology according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Antimicrobial susceptibility was determined using CLSI breakpoints, except for tigecycline for which the US Food and Drugs Administration breakpoints were used. RESULTS: A total of 48.3% (2202/4563) of Staphylococcus aureus isolates were methicillin-resistant S. aureus (MRSA). All MRSA isolates were susceptible to linezolid and vancomycin, and 99.9% (2199/2202) were susceptible to tigecycline. Among Streptococcus pneumoniae isolates, 13.8% (198/1436) were penicillin-resistant; all were susceptible to linezolid and vancomycin, and 98.0% (194/198) were susceptible to tigecycline. Susceptibility was >99.0% for linezolid and tigecycline against Enterococcus faecium and Enterococcus faecalis isolates. A total of 40.8% (235/576) E. faecium and 1.6% (33/2004) E. faecalis isolates were vancomycin-resistant. Among the Enterobacteriaceae, 36.3% (1465/4032) of Klebsiella pneumoniae isolates, 16.4% (67/409) of Klebsiella oxytoca isolates and 25.4% (1246/4912) of Escherichia coli isolates were extended-spectrum ß-lactamase (ESBL) producers. Of the ESBL-producing K. pneumoniae and E. coli isolates, susceptibility was highest to tigecycline [93.4% (1369/1465) and 99.8% (1244/1246), respectively] and meropenem [86.9% (1103/1270) and 97.0% (1070/1103), respectively]. A total of 26.7% (966/3613) of Pseudomonas aeruginosa isolates were multidrug-resistant (MDR). Among all P. aeruginosa isolates, susceptibility was highest to amikacin [72.8% (2632/3613)]. A total of 70.3% (1654/2354) of Acinetobacter baumannii isolates were MDR, and susceptibility was highest to minocycline [88.3% (2079/2354) for all isolates, 86.2% (1426/1654) for MDR isolates]. Tigecycline had the lowest MIC90 (2 mg/L) among A. baumannii isolates, including MDR isolates. CONCLUSIONS: This study of isolates from Latin America shows that linezolid, vancomycin and tigecycline continue to be active in vitro against important Gram-positive organisms such as MRSA, and that susceptibility rates to meropenem and tigecycline against members of the Enterobacteriaceae, including ESBL-producers, were high. However, we report that Latin America has high rates of MRSA, MDR A. baumannii and ESBL-producing Enterobacteriaceae which require continued monitoring.

[The efficacy and safety of daptomycin for the treatment of Gram-positive bacterial infections in Chinese population].

OBJECTIVE: To investigate the efficacy and safety of daptomycin in Chinese patients with serious infections of Gram-positive coccus. METHODS: Clinical data were retrospectively collected from patients who were suspected with Gram-positive coccal infections and received daptomycin treatment between August 2010 and October 2012. RESULTS: A total of 203 Chinese patients from 26 centers were enrolled in our study, including 94 microbiologically diagnosed. Staphylococcus aureus was the most common pathogen (33%, 31/94) with 45.2% (14/31) methicillin-resistant Staphylococcus aureus (MRSA). According to the infection sites, primary bloodstream infection (45.8%, 93/203) was the most frequent, which was followed by skin and soft tissue infections (15.3%, 31/203). Seventy-seven cases (37.9%, 77/203) had bloodstream infections complicated with other infections (37.9%, 77/203), 13 of which were endocarditis. The clinical efficacy of intention-to-treatment (ITT) and modified ITT (MITT) analysis were 70.44% (143/203) and 78.72% (74/94), respectively. Seven patients (3.4%) represented drug-related adverse effect, but no serious adverse effect was reported. Moderate creatine phosphate kinase (CPK) elevation was observed in 4 patients (2%), which returned to normal range after drug withdrawl. CONCLUSION: Daptomycin is effective and safe for Chinese patients with serious infections of Gram-positive cocci. (registration number NCT10212601).

Real-time quantitative reverse transcription-polymerase chain reaction to detect propionibacterial ribosomal RNA in the lymph nodes of Chinese patients with sarcoidosis.

The aim of this study was to investigate the diagnostic value of using the copy number of propionibacterial rRNA as a biomarker for sarcoidosis. Ribosomal RNA of Propionibacterium acnes and P. granulosum was measured by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) using formalin-fixed and paraffin-embedded tissue of lymph node biopsy from 65 Chinese patients with sarcoidosis, 45 with tuberculosis and 50 controls with other diseases (23 with non-specific lymphadenitis and 27 with mediastinal lymph node metastasis from lung cancer). The receiver operating characteristic (ROC) curve was analysed to determine an optimal cut-off value for diagnosis, and the diagnostic accuracy of the cut-off value was evaluated in additional tissue samples [24 patients with sarcoidosis and 22 with tuberculosis (TB)]. P. acnes or P. granulosum rRNA was detected in 48 of the 65 sarcoidosis samples but only in four of the 45 TB samples and three of the 50 control samples. Analysis of the ROC curve revealed that an optimal cut-off value of the copy number of propionibacterial rRNA for diagnosis of sarcoidosis was 50·5 copies/ml with a sensitivity and specificity of 73·8 and 92·6%, respectively. Based on the cut-off value, 19 of the 24 additional sarcoidosis samples exhibited positive P. acnes or P. granulosum, whereas only one of the 22 additional TB samples was positive, resulting in a sensitivity and specificity of 79·2 and 95·5%, respectively. These findings suggest that propionibacteria might be associated with sarcoidosis granulomatous inflammation. Detection of propionibacterial rRNA by RT-PCR might possibly distinguish sarcoidosis from TB.

Population-based survey of invasive bacterial diseases, Greenland, 1995-2004.

Invasive bacterial disease occurs frequently among native populations in the Arctic. Although a variety of bacteria are involved in invasive bacterial disease in Greenland, Streptococcus pneumoniae, Escherichia coli, Staphylococcus aureus, and other staphylococci are responsible for most cases (69%); incidence varies according to region and ethnicity.