Role Of Susceptibility Testing Research Articles

Treatment and Outcome of Culture-Confirmed Mycobacterium marinum Disease.

Background Mycobacterium marinum is a nontuberculous mycobacterium that causes skin and soft tissue infections. Treatment consists of multiple antibiotics, sometimes combined with surgical debridement. There is little evidence for the choice of antibiotics, the duration of treatment, and the role of susceptibility testing.MethodsWe performed a retrospective cohort study of culture-confirmed M. marinum infections in the Netherlands in the 2011–2018 period. Clinical characteristics, in vitro susceptibility, extent of disease, treatment regimens, and outcomes were analyzed. Incidence was assessed from laboratory databases.ResultsForty cases of M. marinum infection could be studied. Antibiotic treatment cured 36/40 patients (90%) after a mean treatment duration of 25 weeks. Failure/relapse occurred in 3 patients, and 1 patient was lost to follow-up. Antibiotic treatment consisted of monotherapy in 35% and 2-drug therapy in 63%. Final treatment contained mostly ethambutol–macrolide combinations (35%). Eleven patients (28%) received additional surgery. We recorded high rates of in vitro resistance to tetracyclines (36% of isolates). Tetracycline resistance seemed correlated with poor response to tetracycline monotherapy. The annual incidence rate was 0.15/100 000/year during the study period.ConclusionsProlonged and susceptibility-guided treatment results in a 90% cure rate in M. marinum disease. Two-drug regimens of ethambutol and a macrolide are effective for moderately severe infections. Tetracycline monotherapy in limited disease should be used vigilantly, preferably with proven in vitro susceptibility.

Antifungal Susceptibility Testing: A Primer for Clinicians

Antifungal susceptibility testing is not as commonly performed as antibacterial susceptibility testing. The methodology for detecting antifungal resistance is newer and requires different testing supplies that may not be readily available in a clinical laboratory setting. Breakpoints for molds are lacking. Yeast breakpoints are available for most antifungals but are continually updated based on epidemiologic surveillance. Reliable and reproducible antifungal susceptibility testing methods, as well as more research on the role of susceptibility testing in patient care, are necessary in order to provide the clinician with information that can be translated into positive clinical outcomes at the bedside. There are nuances with current testing methods that, if unrecognized, could lead to misinterpretation of results and inappropriate antifungal selection. Clinicians who have an understanding of qualitative and quantitative methods, automated susceptibility testing systems, and other commercial tests can successfully engage this knowledge to improve antifungal use and patient outcomes. This primer describes the common antifungal susceptibility tests used in the clinical microbiology laboratory and reviews literature related to the impact of appropriate drug selection, timing, fungal resistance mechanisms, pharmacokinetics, and pharmacodynamics on clinical outcomes. Both conventional and modern testing methods are discussed.

Current issues in the clinical management of invasive candida infections – the AGIHO, DMykG, ÖGMM and PEG web‐based survey and expert consensus conference 2009

The objectives of this study were to identify unsolved issues in the management of invasive candidiasis, identify controversies and achieve consensus. The German Speaking Mycological Society (Deutschsprachige Mykologische Gesellschaft, DMykG e.V.) asked other German infectious diseases (ID) and mycological societies to submit unsolved issues concerning the diagnosis and treatment of fungal infections. Based on these contributions, a digital web-based questionnaire of 12 questions on Candida infections was designed to be completed by experts of the participating societies. Controversial results were identified by a mathematical model and were discussed at a consensus conference during the 43rd Annual Meeting of the DMykG e.V. in Cologne, Germany. Forty-two individuals completed the questionnaire. Analysis showed a strong consensus on treatment indications, choice of antifungals for clinical situations, handling of central venous catheters, duration of treatment and role of susceptibility testing. Opinions diverged on: initial treatment of haemodynamically stable neutropenic and haemodynamically unstable non-neutropenic patients, step down to oral treatment and the differential role of the echinocandins. These questions were presented for discussion at the expert consensus conference. In three of four questions, consensus was achieved. A two-step approach - web-based survey plus classical panel discussion - allows to capture expeditiously the opinions of a large and diverse group of individuals, to identify controversial issues and to resolve them in a personal, interactive setting. Thus, expert consensus was achieved on nine of 12 important questions on how to treat invasive candidiasis.

Effective regimens for the treatment of Helicobacter pylori infection

Successful Helicobacter pylori eradication therapy remains a challenge in medical practice. Currently, a proton pump inhibitor-based triple therapy containing clarithromycin, amoxicillin or nitroimidazole for 7 days is the recommended first-line treatment approach with an expected eradication success rate of ∼ 80%. As a second-line treatment option in the case of failure, a ranitidine bismuth citrate-based quadruple therapy is currently recommended curing another 80% of patients, leaving a subset of patients with persistent H. pylori infection. For these patients, promising rescue options have been evaluated including regimens that contain rifabutin, quinolones, furazolidone or high-dose amoxicillin. The role of susceptibility testing is still under discussion. It is not generally recommended prior to first-line treatment but guidelines propose a role for culture and antibiotic sensitivity testing after failure of the second attempt. Meanwhile, data on the geographic distribution of resistance pattern are available and may guide therapeutic decisions with regard to the combination of antibiotics chosen for the individual patients aiming at 100% cure rate in each individual patient.

Anaerobes: Antibiotic resistance, clinical significance, and the role of susceptibility testing

Anaerobes: Antibiotic resistance, clinical significance, and the role of susceptibility testing

Susceptibility testing today: myth, reality, and new direction.

Recent concerns about the clinical relevance of susceptibility testing echo those expressed previously by a number of authors.’-” These concerns are well founded and are perhaps even more important today because of the proliferation of new antibiotics and the changes in reimbursement philosophy.” Ultimately, the question becomes that raised by David Greenwood: “In vitro veritas?” The following discussion will review the role of susceptibility testing in clinical medicine with emphasis on myth versus reality. In addition, new directions for susceptibility testing that promise increased clinical relevance will be covered.

The Role of Susceptibility Testing in Appropriate Selection of Antibiotics

The Role of Susceptibility Testing in Appropriate Selection of Antibiotics