Medical treatment of staphylococcal infective endocarditis

Staphylococcal infective endocarditis is a severe event requiring aggressive therapy. Antibiotic regimen depends mainly on (1) the species of Staphylococcus (Staphylococcus aureus versus coagulase-negative staphylococci) and its resistance pattern (resistance to penicillin, to methicillin, to multiple classes of antibiotics); (2) the type of infected valve (native versus prosthetic); (3) the site of infection (left side versus right side endocarditis); (4) some underlying conditions of the host, in particular the presence or not of intravenous drug abuse. Based on in vitro susceptibility results, animal models and clinical trials, the following regimens are currently recommended. For native valve endocarditis, penicillin G 20 million units per i.v. for 4-6 weeks for penicillin-susceptible strains; a penicillinase-resistant penicillin (oxacillin) 2 g i.v. q 4 h for 4-6 weeks plus an aminoglycoside (gentamicin) 1.0 mg.kg−1 i.v. q 8 h for 1 week, for penicillin-resistant, methicillin-susceptible strains; for methicillin resistant strains, vancomycin 30 mg.kg.day−1 i.v. in 2—4 doses for 4—6 weeks with the addition or not of rifampin 600-900 mg.day−1 orally. For a prosthetic valve endocarditis, a three-drug regimen (oxacillin or vancomycin, plus gentamicin and rifampin) and a longer duration (6 weeks or more) are generally recommended. Shorter (2 weeks) treatment could be delivered to uncomplicated cases of right-sided endocarditis. In view of an increased resistance to classic drugs and suboptimal efficacy of some of them, new therapeutic modalities should be looked at, in particular for endocarditis cases due to methicillin-resistant strain

Evaluation of the susceptibility of pathogenic Candida species to fluconazole

A fluconazole 25 ug disk diffusion test was used to test 2230 consecutively isolatedCandida strains from 42 different hospital laboratories in 23 countries. Ninety seven percent of 1634Candida albicans isolates and 83.4% of 596 non-Candida albicans isolates were susceptible to fluconazole, applying the proposed breakpoints (≥26 mm for susceptible strains and 18-25 mm for dosedependent susceptible strains). This is the first hospital laboratory study to evaluate a large number and wide range of sequentialCandida isolates from patients with all types of hospital infections. The fluconazole disk diffusion test appears to be a low-cost, reproducible, and accurate means of assessing the in vitro susceptibility ofCandida isolate

Genome Sequences of Listeria monocytogenes Strains Responsible for Cheese- and Cooked Ham Product-Associated Swiss Listeriosis Outbreaks in 2005 and 2011.

The complete genome sequences of three Listeria monocytogenes serotype 1/2a strains, Lm 3136, Lm 3163, and Lm N1546, which were responsible for listeriosis outbreaks in 2005 and 2011 in Switzerland, are presented here

Single-Dose Rifampin Prophylaxis for Experimental Endocarditis Induced by High Bacterial Inocula of Viridans Streptococci

In rats challenged with viridans streptococci poorly susceptible to antibiotic killing, single doses of antibiotics only prevent endocarditis induced by bacterial inoculum sizes that produce disease in 90% of control animals (ID90) : additional doses are required to protect against inocula exceeding the ID90. We investigated whether single-dose rifampin would extend the efficacy of single-dose prophylaxis to inocula exceeding the ID90. We used two strains of viridans streptococci highly susceptible to killing by rifampin and two resistant strains. All rats wereinjected with 10-1,000 times the ID90 of the four strains. Single-dose rifampin successfully prevented endocarditis due to all four strains. A few prophylaxis failures were observed after challenge with the two poorly susceptible strains, but in vivo emergence of resistant variants did not account for these failures. Thus, rifampin was the first antibiotic given as a single dose that successfully prevented experimental streptococcus endocarditis after challenge with high bacterial inocul

Prophylaxis of pyelonephritis by aminoglycosides accumulated in the kidney

When given prophylactically, gentamicin accumulates and persists in the rat kidney and affords protection against obstructive acute Escherichia coli pyelonephritis. Similar protection is observed after administration of amikacin, netilmicin and tobramycin, which accumulate to various degrees in the renal parenchyma. In those animals developing pyelonephritis despite aminoglycoside prophylaxis, renal infection and inflammation are reduced during the acute phase of the disease. This results in almost complete protection against renal scarring later on. Administrée à titre prophylactique, la Gentamicine s'accurnule dans le rein du rat et le protège contre l'apparition de pyélonéphrite aiguë à E. coli. Un effet protecteur identique est observé aprés administration d'Amikacine, de Nétilmicine, et de Tobramycine, qui s'accumulent à des degrés divers dans le parenchyme rénal. Chez l'animal, lorsqu'apparait une pyélonéphrite, malgré le traitement prophylactique par les aminoglycosides, l'infection et l'inflammation rénales sont diminuées durant la phase aiguë de la maladie. Ceci réduit le risque de lésion et de formation ultérieure de tissu cicatricie

Enterococcus cecorum septicemia in a malnourished adult patient

Enterococcus cecorum, a species typically isolated from chicken, pigs, calves, horses, ducks, cats, dogs, and canaries, was isolated from the blood of a patient with severe septicemia. The isolate was identified by conventional biochemical tests. Identity asEnterococcus cecorum was confirmed by SDS-PAGE analysis of whole cell protein. This is the first report of the isolation ofEnterococcus cecorum in a clinical settin

Fast Arc-Annotated Subsequence Matching in Linear Space

An arc-annotated string is a string of characters, called bases, augmented with a set of pairs, called arcs, each connecting two bases. Given arc-annotated strings $P$ and $Q$ the arc-preserving subsequence problem is to determine if $P$ can be obtained from $Q$ by deleting bases from $Q$. Whenever a base is deleted any arc with an endpoint in that base is also deleted. Arc-annotated strings where the arcs are ``nested'' are a natural model of RNA molecules that captures both the primary and secondary structure of these. The arc-preserving subsequence problem for nested arc-annotated strings is basic primitive for investigating the function of RNA molecules. Gramm et al. [ACM Trans. Algorithms 2006] gave an algorithm for this problem using $O(nm)$ time and space, where $m$ and $n$ are the lengths of $P$ and $Q$, respectively. In this paper we present a new algorithm using $O(nm)$ time and $O(n + m)$ space, thereby matching the previous time bound while significantly reducing the space from a quadratic term to linear. This is essential to process large RNA molecules where the space is likely to be a bottleneck. To obtain our result we introduce several novel ideas which may be of independent interest for related problems on arc-annotated strings.Comment: To appear in Algoritmic