The geographic diversity of nontuberculous mycobacteria isolated from pulmonary samples: an NTM-NET collaborative study.

A significant knowledge gap exists concerning the geographical distribution of nontuberculous mycobacteria (NTM) isolation worldwide. To provide a snapshot of NTM species distribution, global partners in the NTM-Network European Trials Group (NET) framework (www.ntm-net.org), a branch of the Tuberculosis Network European Trials Group (TB-NET), provided identification results of the total number of patients in 2008 in whom NTM were isolated from pulmonary samples. From these data, we visualised the relative distribution of the different NTM found per continent and per country. We received species identification data for 20 182 patients, from 62 laboratories in 30 countries across six continents. 91 different NTM species were isolated. Mycobacterium avium complex (MAC) bacteria predominated in most countries, followed by M. gordonae and M. xenopi. Important differences in geographical distribution of MAC species as well as M. xenopi, M. kansasii and rapid-growing mycobacteria were observed. This snapshot demonstrates that the species distribution among NTM isolates from pulmonary specimens in the year 2008 differed by continent and differed by country within these continents. These differences in species distribution may partly determine the frequency and manifestations of pulmonary NTM disease in each geographical location.

Microbiologic characteristics and in vitro susceptibility to antimicrobials in a large population of patients with cardiovascular implantable electronic device infection.

INTRODUCTION: The incidence of cardiovascular implantable electronic device (CIED) infection is steadily increasing. However, no consensus has been reached with respect to the type and duration of antimicrobial therapy in this specific population of patients. The role played by new anti-Staphylococcus agents has not been defined. The aims of this study were to describe the microbiological characteristics of a large population of patients with CIED infections and to test the in vitro susceptibility of the various strains to different antimicrobials. METHODS: Two hundred eighty-six patients with CIED infection were included. The minimal inhibitory concentrations of 9 antimicrobials, including linezolid, tigecycline, and daptomycin were measured against all strains of staphylococci isolated. RESULTS: Microbiologic confirmation was obtained in 252 (88%) patients, the vast majority were from Staphylococcus species (86%), 90% of these were coagulase negative strains and 10% were Staphylococcus aureus; 30.5% were methicillin-resistant. All strains were susceptible to vancomycin, nearly 15% of coagulase negative strains were nonsusceptible to teicoplanin, and nearly 100% of the strains were susceptible to the 3 new antimicrobials. CONCLUSIONS: In this large contemporary study, we show that Staphylococcus is by far the most common cause of CIED infections, with the majority due to coagulase negative strains. Methicillin-resistance is common in this population. Currently, we would recommend vancomycin as first-line empirical therapy. However, given that not all patients tolerate vancomycin, we believe that newer antimicrobial therapies should now be tested in clinical trials to establish their clinical effectiveness in treating patients with device infections.

Gammadelta T lymphocytosis associated with granulomatous disease in a patient with common variable immunodeficiency.

Common variable immunodeficiency (CVID) is a heterogeneous group of immunodeficiency syndromes that involves defective production of specific antibodies and decreased serum concentrations of > or =1 immunoglobulin isotype. We describe a patient with an atypical case of CVID who had extensive granulomatous lesions that were partially attributable to mycobacterial infection. In the peripheral blood, there was a massive increase in the number of double-negative CD3+ T cells that expressed the gammadelta T cell receptor.

Carbapenems.

OBJECTIVE: To assess the relative strengths and weaknesses of carbapenems by considering their microbiological, clinical, pharmacokinetics and pharmacokinetic/pharmacodynamic (PK/PD) properties and defining optimal conditions of uses of the new generation of carbapenems. METHODS: Literature review. RESULTS: Except for ertapenem, the spectrum of activity is similar for all carbapenems, with little differences in activities of individual agents. The absence or reduced expression of two major porins in combination with various beta-lactamases and alteration of some penicillin binding proteins have been implicated in carbapenem resistance. All carbapenems are not alike, although they have very similar pharmacokinetic properties. The most important PK/PD parameter predicting bacteriological and clinical efficacy is T(>MIC). There is some circumstantial evidence, such as clinical data in severe critically ill septic patients, impaired renal function patients and neutropenic patients that imipenem has to exceed 66% of T(>MIC) to result in good clinical outcome. Continuous or extend infusion of carbapenems should result in at least equal efficacy to that of intermittent infusion in the treatment of infections with susceptible bacteria and appear highly appropriate for use in critically ill patients. CONCLUSIONS: Maximizing clinical outcomes and minimizing antibiotic resistance using individualized doses may be best achieved with therapeutic drug monitoring of carbapenems.