Spinal epidural abscess from group A Streptococcus after varicella infection: a case report and review of the literature.

INTRODUCTION: Spinal epidural abscess (SEA) is a very rare condition in pediatric patients. Varicella zoster infection could be a predisposing factor, and SEA should be suspected in patients with signs of secondary bacterial infection and even mild neurological signs. CLINICAL CASE: We describe here a case of a 30-month-old girl with a history of remitting varicella infection, diagnosed for a lumbar epidural abscess and sacro-ileitis, secondary to group A Streptococcus (GAS). DISCUSSION: This is the third case of SEA from GAS reported in the literature in a pediatric population with varicella infection. We discuss here the clinical presentation and the diagnostic challenges for SEA in childhood through a review of the literature.

Predictors of endocarditis in isolates from cultures of blood following dental extractions in rats with periodontal disease.

Rats with periodontitis and catheter-induced aortic valve vegetations underwent dental extractions. Cultures of blood obtained 1 min later showed polymicrobial bacteremia in 19 of 19 rats, mostly due to viridans streptococci (18 of 19), Morganella (15 of 19), group G streptococci (13 of 19), and Staphylococcus aureus (10 of 19). Viridans streptococci circulated in higher numbers than did group G streptococci and S. aureus (P less than .01). Three days after dental extractions, 18 of 20 rats had endocarditis. Fifteen (83%) of 18 infections were due to group G streptococci, 9 (50%) of 18 were due to S. aureus, and 2 (11%) of 18 were due to viridans streptococci (P less than .05). In vitro, adherence to platelet-fibrin matrices of endocarditis strain 8 of group G streptococcus was two times greater than that of endocarditis strain S. aureus 23 and three to four times greater than that of Streptococcus sanguis 44 and Morganella morganii 93 (P less than 10(-5)). The inoculum size that produced endocarditis in 90% of rats after iv challenge was 10(5) cfu for group G streptococcus strain 8 and 10(7) for S. sanguis 44.

RP 59500 prophylaxis of experimental endocarditis due to erythromycin-susceptible and -resistant isogenic pairs of viridans group streptococci.

RP 59500 is a new injectable streptogramin composed of two synergistic components (quinupristin and dalfopristin) which are active against a number of erythromycin-susceptible and -resistant gram-positive bacteria. The following experiments investigate the ability of RP 59500 to prevent experimental endocarditis due to either of two erythromycin-susceptible streptococcal isolates or their constitutively erythromycin-resistant Tn916 delta E transconjugants. RP 59500 had low MICs (0.125 to 0.5 mg/liter) for all four test organisms and was substantially bactericidal in vitro. Rats with catheter-induced aortic vegetations were given single-dose antibiotic prophylaxis 30 to 60 min before bacterial inoculation through a computerized pump system which permitted the simulation of drug kinetics for humans produced by either 7 mg of RP 59500 per kg of body weight or 1 g of vancomycin. Single-dose RP 59500 prophylaxis successfully prevented endocarditis due to both the erythromycin-susceptible parent strains and their erythromycin-resistant derivatives in rats challenged with the minimal inoculum infecting 90% of controls. In addition, RP 59500 also prevented infection in animals challenged with fivefold-larger inocula of the erythromycin-susceptible parent strains. Vancomycin successfully prevented endocarditis due to any of the four test organisms. These results underline the in vivo efficacy of RP 59500 against both erythromycin-susceptible and -resistant streptococci. Such good results against the resistant strains would not be expected with erythromycin or clindamycin, which are the standard macrolidelincosamide-streptogramin antibiotics used for endocarditis prophylaxis in humans. An oral form of RP 59500 which might advantageously replace some of the older prophylactic regimens is currently being developed.

Efficacy of garenoxacin in treatment of experimental endocarditis due to Staphylococcus aureus or viridans group streptococci.

The activity of garenoxacin was investigated in rats with experimental endocarditis due to staphylococci and viridans group streptococci (VGS). The staphylococci tested comprised one ciprofloxacin-susceptible and methicillin-susceptible Staphylococcus aureus (MSSA) isolate (isolate 1112), one ciprofloxacin-susceptible but methicillin-resistant S. aureus (MRSA) isolate (isolate P8), and one ciprofloxacin-resistant mutant (grlA) of P8 (isolate P8-4). The VGS tested comprised one penicillin-susceptible isolate and one penicillin-resistant isolate (Streptococcus oralis 226 and Streptococcus mitis 531, respectively). To simulate the kinetics of drugs in humans, rats were infused intravenously with garenoxacin every 24 h (peak and trough levels in serum, 6.1 and 1.0 mg/liter, respectively; area under the concentration-time curve [AUC], 63.4 mg. h/liter) or levofloxacin every 12 h (peak and trough levels in serum, 7.3 and 1.5 mg/liter, respectively; AUC, 55.6 mg. h/liter) for 3 or 5 days. Flucloxacillin, vancomycin, and ceftriaxone were used as control drugs. Garenoxacin, levofloxacin, flucloxacillin, and vancomycin sterilized >/=70% of the vegetations infected with both ciprofloxacin-susceptible staphylococcal isolates (P < 0.05 versus the results for the controls). Garenoxacin and vancomycin also sterilized 70% of the vegetations infected with ciprofloxacin-resistant MRSA isolate P8-4, whereas treatment with levofloxacin failed against this organism (cure rate, 0%; P < 0.05 versus the results obtained with the comparator drugs). Garenoxacin did not select for resistant derivatives in vivo. In contrast, levofloxacin selected for resistant variants in four of six rats infected with MRSA isolate P8-4. Garenoxacin sterilized 90% of the vegetations infected with both penicillin-susceptible and penicillin-resistant isolates of VGS. Levofloxacin sterilized only 22 and 40% of the vegetations infected with penicillin-susceptible S. oralis 226 and penicillin-resistant S. mitis 531, respectively. Ceftriaxone sterilized only 40% of those infected with penicillin-resistant S. mitis 531 (P < 0.05 versus the results obtained with garenoxacin). No quinolone-resistant VGS were detected. In all the experiments successful quinolone treatment was predicted by specific pharmacodynamic criteria (D. R. Andes and W. A. Craig, Clin. Infect. Dis. 27:47-50, 1998). The fact that the activity of garenoxacin was equal or superior to those of the standard comparators against staphylococci and VGS indicates that it is a potential alternative for the treatment of infections caused by such bacteria.

Efficacy of levofloxacin in the treatment of experimental endocarditis caused by viridans group streptococci.

Levofloxacin was investigated against viridans group streptococci in vitro and in rats with experimental aortic endocarditis. The MIC(90)s of levofloxacin and ciprofloxacin for 20 independent isolates of such bacteria were 1 and 8 mg/L, respectively. Rats were infected with two types of organism: either fully susceptible to levofloxacin MIC < or = 0.5 mg/L) or borderline susceptible (MIC 1-2 mg/L). Fully levofloxacin-susceptible bacteria comprised one penicillin-susceptible (MIC 0.004 mg/L) Streptococcus gordonii, and one penicillin-tolerant as well as one intermediate penicillin-resistant (MIC 0.125 mg/L) isogenic strains. Borderline levofloxacin-susceptible bacteria comprised one penicillin-susceptible Streptococcus sanguis and one highly penicillin-resistant Streptococcus mitis (MIC 2 mg/L). Rats were treated for 5 days with drug dosages simulating the following treatments in humans: (i) levofloxacin 500 mg orally once a day (q24 h), (ii) levofloxacin 500 mg orally twice a day (q12 h), (iii) levofloxacin 1 g orally q24 h, (iv) ciprofloxacin 750 mg orally q12 h, and (v) ceftriaxone 2 g iv q24 h. Levofloxacin was equivalent or superior to ceftriaxone, and was successful in treating experimental endocarditis irrespective of penicillin resistance. Nevertheless, standard levofloxacin treatment equivalent to 500 mg q24 h in human was less effective than twice daily 500 mg or once daily 1 g doses against borderline-susceptible organisms. Ciprofloxacin, used as a negative control, was ineffective and selected for resistant isolates. This underlines the importance of MIC determinations when treating severe streptococcal infection with quinolones. In the case of borderline-susceptible pathogens, total daily doses of 1 g of levofloxacin should be considered.

The use of heterogeneous chemistry for the characterization of functional groups at the gas/particle interface of soot and TiO(2) nanoparticles

Six gases (N((CH3)3), NH2OH, CF3COOH, HCl, NO2, O3) were selected to probe the surface of seven combustion aerosol (amorphous carbon, flame soot) and three types of TiO2 nanoparticles using heterogeneous, that is gas-surface reactions. The gas uptake to saturation of the probes was measured under molecular flow conditions in a Knudsen flow reactor and expressed as a density of surface functional groups on a particular aerosol, namely acidic (carboxylic) and basic (conjugated oxides such as pyrones, N-heterocycles) sites, carbonyl (R1-C(O)-R2) and oxidizable (olefinic, -OH) groups. The limit of detection was generally well below 1% of a formal monolayer of adsorbed probe gas. With few exceptions most investigated aerosol samples interacted with all probe gases which points to the coexistence of different functional groups on the same aerosol surface such as acidic and basic groups. Generally, the carbonaceous particles displayed significant differences in surface group density: Printex 60 amorphous carbon had the lowest density of surface functional groups throughout, whereas Diesel soot recovered from a Diesel particulate filter had the largest. The presence of basic oxides on carbonaceous aerosol particles was inferred from the ratio of uptakes of CF3COOH and HCl owing to the larger stability of the acetate compared to the chloride counterion in the resulting pyrylium salt. Both soots generated from a rich and a lean hexane diffusion flame had a large density of oxidizable groups similar to amorphous carbon FS 101. TiO2 15 had the lowest density of functional groups among the three studied TiO2 nanoparticles for all probe gases despite the smallest size of its primary particles. The used technique enabled the measurement of the uptake probability of the probe gases on the various supported aerosol samples. The initial uptake probability, g0, of the probe gas onto the supported nanoparticles differed significantly among the various investigated aerosol samples but was roughly correlated with the density of surface groups, as expected. [Authors]

Virulent infections due to alpha-haemolytic streptococci in cancer patients and their management

Streptococci of the viridans group have long been considered to be minor pathogens, except in bacterial endocarditis. For some years, however, these microorganisms have been the cause of serious bacteraemia in neutropenic patients receiving intensive chemotherapy. These infections can lead to severe complications such as endocarditis, respiratory distress syndromes or shock, and are associated with a mortality rate ranging from 6-30%. The principal risk factors for these infections are profound neutropenia, antibiotic prophylaxis with quinolones or cotrimoxazole, large doses of cytosine arabinoside, a recent history of chemotherapy, oropharyngeal mucositis and viridans streptococcal colonization. Protective factors are the early administration of parenteral antibiotics during periods of neutropenia, or the prophylactic administration of penicillin. Although the introduction of penicillin to prophylactic antibiotic regimens has led to a decrease in the incidence of these infections, the emergence of strains resistant to beta-lactams is a worrying problem which could compromise this type of treatment.

Ink dating using thermal desorption and gas chromatography / mass spectrometry: comparison of results obtained in two laboratories

Recent ink dating methods focused mainly on changes in solvent amounts occurring over time. A promising method was developed at the Landeskriminalamt of Munich using thermal desorption (TD) followed by gas chromatography / mass spectrometry (GC/MS) analysis. Sequential extractions of the phenoxyethanol present in ballpoint pen ink entries were carried out at two different temperatures. This method is applied in forensic practice and is currently implemented in several laboratories participating to the InCID group (International Collaboration on Ink Dating). However, harmonization of the method between the laboratories proved to be a particularly sensitive and time consuming task. The main aim of this work was therefore to implement the TD-GC/MS method at the Bundeskriminalamt (Wiesbaden, Germany) in order to evaluate if results were comparable to those obtained in Munich. At first validation criteria such as limits of reliable measurements, linearity and repeatability were determined. Samples were prepared in three different laboratories using the same inks and analyzed using two TDS-GC/MS instruments (one in Munich and one in Wiesbaden). The inter- and intra-laboratory variability of the ageing parameter was determined and ageing curves were compared. While inks stored in similar conditions yielded comparable ageing curves, it was observed that significantly different storage conditions had an influence on the resulting ageing curves. Finally, interpretation models, such as thresholds and trend tests, were evaluated and discussed in view of the obtained results. Trend tests were considered more suitable than threshold models. As both approaches showed limitations, an alternative model, based on the slopes of the ageing curves, was also proposed.

Mediterranean populations of the lesser white-toothed shrew (Crocidura suaveolens group): an unexpected puzzle of Pleistocene survivors and prehistoric introductions.

An earlier study revealed the strong phylogeographical structure of the lesser white-toothed shrew (Crocidura suaveolens group) within the northern Palaearctic. Here, we aim to reconstruct the colonization history of Mediterranean islands and to clarify the biogeography and phylogeographical relationships of the poorly documented Middle East region with the northern Palaearctic. We performed analyses on 998-bp-long haplotypes of the mitochondrial cytochrome b gene of 143 samples collected around the Mediterranean basin, including islands and the Middle East. The analyses suggest that the Cypriot shrew belongs to the rare group of relict insular Pleistocene mammal taxa that have survived to the present day. In contrast, the Cretan, Corsican and Menorcan populations were independently introduced from the Middle East during the Holocene. The phylogeographical structure of this temperate Palaearctic species within the Middle East appears to be complex and rich in diversity, probably reflecting fragmentation of the area by numerous mountain chains. Four deeply divergent clades of the C. suaveolens group occur in the area, meaning that a hypothetical contact zone remains to be located in central western Iran.

Five-day plan for smoking cessation using group behaviour therapy.

The "Five-Day Plan to Stop Smoking" (FDP) is an educational group technique for smoking cessation. We studied a cohort of 123 smokers (55 men, 68 women, mean age 42 years) who participated in 11 successive FDP sessions held in Switzerland between 1995 and 1998 and who were followed up for at least 12 months by telephone or direct interview. Overall, 102 of the 123 subjects (83%) had stopped smoking by the end of the FDP, and self-declared smoking cessation rate was 25% after one year. The following factors potentially associated with outcome were studied: age, sex, smoking habit duration, cigarettes per day, Fagerström Test for Nicotine Dependence (FTND), group size, and medical presence among the group leaders. Smoking habit duration was the only variable which showed a statistically significant association with success: the rate of smoking cessation was higher among patients who had smoked for less than 20 years (34.7% vs. 18.9%, p = 0.049). Stress was the most common cause of relapse. The FDP appears to be an effective smoking cessation therapy. Propositions are made in order to improve the success rate of future sessions.

International Society of Urological Pathology (ISUP) Consensus Conference on Handling and Staging of Radical Prostatectomy Specimens. Working group 2: T2 substaging and prostate cancer volume.

The 2009 International Society of Urological Pathology consensus conference in Boston made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to the substaging of pT2 prostate cancers according to the TNM 2002/2010 system, reporting of tumor size/volume and zonal location of prostate cancers were coordinated by working group 2. A survey circulated before the consensus conference demonstrated that 74% of the 157 participants considered pT2 substaging of prostate cancer to be of clinical and/or academic relevance. The survey also revealed a considerable variation in the frequency of reporting of pT2b substage prostate cancer, which was likely a consequence of the variable methodologies used to distinguish pT2a from pT2b tumors. Overview of the literature indicates that current pT2 substaging criteria lack clinical relevance and the majority (65.5%) of conference attendees wished to discontinue pT2 substaging. Therefore, the consensus was that reporting of pT2 substages should, at present, be optional. Several studies have shown that prostate cancer volume is significantly correlated with other clinicopathological features, including Gleason score and extraprostatic extension of tumor; however, most studies fail to demonstrate this to have prognostic significance on multivariate analysis. Consensus was reached with regard to the reporting of some quantitative measure of the volume of tumor in a prostatectomy specimen, without prescribing a specific methodology. Incorporation of the zonal and/or anterior location of the dominant/index tumor in the pathology report was accepted by most participants, but a formal definition of the identifying features of the dominant/index tumor remained undecided.

Primary localized rectal/pararectal gastrointestinal stromal tumors: results of surgical and multimodal therapy from the French Sarcoma group.

BACKGROUND: Rectal and pararectal gastrointestinal stromal tumors (GISTs) are rare. The optimal management strategy for primary localized GISTs remains poorly defined. METHODS: We conducted a retrospective analysis of 41 patients with localized rectal or pararectal GISTs treated between 1991 and 2011 in 13 French Sarcoma Group centers. RESULTS: Of 12 patients who received preoperative imatinib therapy for a median duration of 7 (2-12) months, 8 experienced a partial response, 3 had stable disease, and 1 had a complete response. Thirty and 11 patients underwent function-sparing conservative surgery and abdominoperineal resection, respectively. Tumor resections were mostly R0 and R1 in 35 patients. Tumor rupture occurred in 12 patients. Eleven patients received postoperative imatinib with a median follow-up of 59 (2.4-186) months. The median time to disease relapse was 36 (9.8-62) months. The 5-year overall survival rate was 86.5%. Twenty patients developed local recurrence after surgery alone, two developed recurrence after resection combined with preoperative and/or postoperative imatinib, and eight developed metastases. In univariate analysis, the mitotic index (≤5) and tumor size (≤5 cm) were associated with a significantly decreased risk of local relapse. Perioperative imatinib was associated with a significantly reduced risk of overall relapse and local relapse. CONCLUSIONS: Perioperative imatinib therapy was associated with improved disease-free survival. Preoperative imatinib was effective. Tumor shrinkage has a clear benefit for local excision in terms of feasibility and function preservation. Given the complexity of rectal GISTs, referral of patients with this rare disease to expert centers to undergo a multidisciplinary approach is recommended.

Results of a collaborative study of the EDNAP group regarding mitochondrial DNA heteroplasmy and segregation in hair shafts.

A collaborative exercise was carried out by the European DNA Profiling Group (EDNAP) in order to evaluate the distribution of mitochondrial DNA (mtDNA) heteroplasmy amongst the hairs of an individual who displays point heteroplasmy in blood and buccal cells. A second aim of the exercise was to study reproducibility of mtDNA sequencing of hairs between laboratories using differing chemistries, further to the first mtDNA reproducibility study carried out by the EDNAP group. Laboratories were asked to type 2 sections from each of 10 hairs, such that each hair was typed by at least two laboratories. Ten laboratories participated in the study, and a total of 55 hairs were typed. The results showed that the C/T point heteroplasmy observed in blood and buccal cells at position 16234 segregated differentially between hairs, such that some hairs showed only C, others only T and the remainder, C/T heteroplasmy at varying ratios. Additionally, differential segregation of heteroplasmic variants was confirmed in independent extracts at positions 16093 and the poly(C) tract at 302-309, whilst a complete A-G transition was confirmed at position 16129 in one hair. Heteroplasmy was observed at position 16195 on both strands of a single extract from one hair segment, but was not observed in the extracts from any other segment of the same hair. Similarly, heteroplasmy at position 16304 was observed on both strands of a single extract from one hair. Additional variants at positions 73, 249 and the HVII poly(C) region were reported by one laboratory; as these were not confirmed in independent extracts, the possibility of contamination cannot be excluded. Additionally, the electrophoresis and detection equipment used by this laboratory was different to those of the other laboratories, and the discrepancies at position 249 and the HVII poly(C) region appear to be due to reading errors that may be associated with this technology. The results, and their implications for forensic mtDNA typing, are discussed in the light of the biology of hair formation.

Indirect hydrogen analysis by gas chromatography coupled to mass spectrometry (GC-MS).

Gas chromatography (GC) is an analytical tool very useful to investigate the composition of gaseous mixtures. The different gases are separated by specific columns but, if hydrogen (H2 ) is present in the sample, its detection can be performed by a thermal conductivity detector or a helium ionization detector. Indeed, coupled to GC, no other detector can perform this detection except the expensive atomic emission detector. Based on the detection and analysis of H2 isotopes by low-pressure chemical ionization mass spectrometry (MS), a new method for H2 detection by GC coupled to MS with an electron ionization ion source and a quadrupole analyser is presented. The presence of H2 in a gaseous mixture could easily be put in evidence by the monitoring of the molecular ion of the protonated carrier gas. Copyright © 2013 John Wiley &amp; Sons, Ltd.

Validation of an analytical method for nitrous oxide (N2O) laughing gas by headspace gas chromatography coupled to mass spectrometry (HS-GC-MS): Forensic application to a lethal intoxication.

Drug abuse is a widespread problem affecting both teenagers and adults. Nitrous oxide is becoming increasingly popular as an inhalation drug, causing harmful neurological and hematological effects. Some gas chromatography-mass spectrometry (GC-MS) methods for nitrous oxide measurement have been previously described. The main drawbacks of these methods include a lack of sensitivity for forensic applications; including an inability to quantitatively determine the concentration of gas present. The following study provides a validated method using HS-GC-MS which incorporates hydrogen sulfide as a suitable internal standard allowing the quantification of nitrous oxide. Upon analysis, sample and internal standard have similar retention times and are eluted quickly from the molecular sieve 5Å PLOT capillary column and the Porabond Q column therefore providing rapid data collection whilst preserving well defined peaks. After validation, the method has been applied to a real case of N2O intoxication indicating concentrations in a mono-intoxication.