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The fight against antibiotic resistance must incorporate the “One Health” concept to be effective. This means having a holistic approach embracing the different ecosystems, human, animal, and environment. Transfers of resistance genes may exist between these three domains and different stresses related to the exposome may influence these transfers. Various targeted or pan-genomic molecular biology techniques can be used to better characterise the dissemination of bacterial clones and to identify exchanges of genes and mobile genetic elements between ecosystems.

We report here a rare case of chronic subdural hematoma infected by Campylobacter fetus in a 86-year-old woman. She was admitted for confusion and disorientation in a context of high fever and diarrhoea. After two surgeries, the evolution was finally good with a combination of antibiotics (amoxicillin and clindamycin). Chronic subdural hematoma is a potential site for bacterial infection. Our case suggests that C. fetus infection should be suspected in elderly patients presenting with fever and enteritis. The frequency of such cases may be underestimated, due to the difficult diagnosis of C. fetus. It is also suspected that C. fetus could play a role in the recurrence of hematoma, because of its vessel tropism., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Classical methods are still providing new vaccines, but molecular biology and genetic engineering have enabled new approaches to development. Changes in vaccinology have involved the isolation, presentation and administration of vaccinal antigens or attenuated vaccinal strains. New methods of vaccine delivery other than injection will be used (e.g. mucosal administration) and new vectors or adjuvants will be added to vaccines in order to stimulate specific responses. New vaccines can also be obtained by using viral-like particles (VLP of papillomavirus), conjugate polysaccharides (N. meningitidis, S. pneumoniae) or the reassortment of segmented genomes (rotavirus, influenza). Here, we analyze the different steps of a vaccine's life using concrete cases of two new vaccines against papillomavirus and rotavirus. Vaccination has a promising future.

Background: Increased frequency of methiresistant Staphylococcus aureus (MRSA) in inpatients is a day to day problem., Objective: To determine the origin of MRSA, the causes for contamination, and potential complications in a department of Dermatology., Patients and Methods: A retrospective study of patients hospitalized in a dermatology department with cutaneous MRSA during 1997-1998. We considered age, type and duration of dermatitis, geographic origin of patients on admission, previous hospitalizations, time between arrival in the ward and positive MRSA, and complications requiring systemic antibiotics., Results: Out of 4579 of our patients, 53 (0.011 p. 100) had positive MRSA. They were on average 70.86 years-old (26 to 97). The most common underlying dermatitis was leg ulcers (30) and foot sores (4). Dermatitis had lasted for more than 1 month in 48 patients. Most of the patients (40) had their MRSA on admission to our ward. Twenty six patients admitted from home had MRSA; only 9 had never been in an hospital. Six patients had diabetes mellitus. Thirty two patients healed with local treatment for their dermatitis. Thirteen patients have had some complications (erysipela 1, osteoarthritis 3, septicemia 2, febrile syndrome 9)., Discussion: Most patients with MRSA had leg ulcers or foot sores, confirming liability of chronic wounds to MRSA colonizing. Thirty one out of 40 patients with MRSA at arrival had been previously hospitalized. Hospitalization increases the risk of MRSA contamination. Treatment of MRSA is essentially that of the underlying dermatitis. However, it is still necessary to monitor the lesion for complications.

Streptococcus pyogenes is considered as the primary cause of erysipelas and the virulence factors of this species are reviewed. The role of Staphylococcus aureus alone or associated with Streptococcus pyogenes remains unclear. Other etiologies are infrequent. Several techniques were used to detect bacteria (direct examination, culture, antigen or genome assay) in local samples (needle aspiration, swab.), in others sites (throat, blood cultures), or specific antibodies. The performance of the various diagnosis methods is evaluated. Despite the combination of 2 or more methods, the etiology remains unknown in almost 20 p. 100 of the cases.

Bacteria can transfer genetic information to get protection against most antibiotics. The acquisition of resistance genes involves genetic mobile elements such as plasmids and transposons. Another genetic structures, named integrons, have been described and contain one or more gene cassettes located at a specific site. Integrons contain an intI gene encoding a site-specific recombinase belonging to the integrase family and a recombination site attI. A gene cassette includes an open reading frame and, at the 3'-end, a recombination site attC. Integration or excision of cassettes occurs by a site-specific recombination mechanism catalyzed by the integrase. However, insertion can rarely occur, at non-specific sites leading to a stable situation for the cassette. Cassettes are transcribed from a common promoter located in the 5'-conserved segment and expression of distal genes is reduced by the presence of upstream cassettes. Most gene cassettes encode antibiotic resistant determinants but antiseptic resistant genes have also been described. Integrons seem to have a major role in the spread of multidrug resistance in Gram-negative bacteria but integrons in Gram-positive bacteria have been recently described. Moreover, the finding of super-integrons with gene cassettes coding for other determinants (biochemical functions, virulence factors) in different Gram negative bacteria suggests that integrons are probably implied in bacterial genome evolution.

Bacteriological samples and tests are essentiel for the diagnosis of superficial ocular infections and endophtalmitis. The direct examination and the traditional culture of the samples can be in the futur associated with new diagnostic approach using antigen detection (immunofluorescence, enzyme immunosorbent assays) and genome research by hybridation or better by amplification for Chlamydia and for the most frequent species responsible of endophtalmitis. An original genomic strategy of bacterial endophtalmitis diagnosis was developped.

Background: Lactobacillus is a commensal germ found in the buccal cavity, the digestive tract and the vagina. Usually non-pathogenic except in case of dental caries, it can occasionally be the causal agent in severe endocarditis., Case Report: A 70-year-old woman developed endocarditis on an aortic valve bioprosthesis. Lactobacillus acidophilus was isolated from blood cultures of the valve after surgery., Comments: Forty-four cases of Lactobacillus endocarditis have been reported in the literature to date. Mortality is high (26%). The main difficulty in treatment is germ tolerance to penicillin and aminosides found in all cases. Cure requires high dose parenteral antibiotics and surgery in many cases (26%).

Numerous viruses found in the gut are not associated with primary infection or disease of the gastrointestinal tract. Other groups or viruses are not classically associated with infection of the gut but can infect the gastrointestinal tract in immunocompromised individuals (herpes simplex virus, cytomegalovirus, papillomavirus ....). The viruses associated with gastroenteritis represent a large number of taxonomic group. Because these viruses have in general been difficult to cultivate, most members of this group were firstly detected by electron microscopic examination (adenovirus, astrovirus, calicivirus, coronavirus, rotavirus ....). The most widely used diagnostic techniques for adenovirus (40/41), rotavirus and astrovirus detection in faecal samples include immunoassays such as Elisa and latex agglutination. Nucleic acid hybridization techniques have generally not proven to be substantially sensitive and the more sensitive techniques recently developed use the polymerase chain reaction (adenovirus) or the reverse transcription/polymerase chain reaction (astrovirus, calicivirus, coronavirus, rotavirus). Special efforts have been made in the search for efficient procedures to extract viral nucleic acids, and to establish the optimal conditions for the amplification and identification of PCR products but the candidate viruses were very different, consensus procedures were not determined, and amplification kits were not actually commercialized.

From the beginning of the year 1996, an increase of multiresistant Enterobacter aerogenes isolates was observed. These strains overproduced their chromosomally cephalosporinase. From February to September 1996, we studied the genotypic diversity of multiresistant E. aerogenes isolates. Fifty-seven strains were analysed with the RAPD technique. These strains were isolated from 38 patients in 25 different units. These isolates were collected from urines (37), respiratory tracts (14) and wounds (6). We have observed two distinct profiles. The predominant profile (A) was recovered from 55 strains (36 patients) and the second profile (B) from 2 strains (2 patients). The clonal relatedness of strains isolated (profile A) showed an epidemic spread in our hospital. The RAPD technique is easy to perform and gives results in less than 48 h with a good discriminatory power.

During a six-years period (1988-1993), a total of 14,644 stool samples from in-patients of Limoges University Hospital were examined for the presence of principal enteric pathogens, such as adenovirus, rotavirus, Campylobacter, Salmonella, Shigella and others. Stools were processed for identification of bacteria by standard methods and viruses were detected in fecal specimens using antigen detection methods: ELISA (Enzyme Linked Immunosorbent Assay) and latex agglutination test. The decreasing rates of presence of enteric agents were respectively 6% for rotavirus, 3.2% for Salmonella, 2% for adenovirus, 1.6% for Campylobacter and 0.2% for Shigella, but according to the lack of sensibility of latex agglutination test, adenovirus prevalence was probably underestimated. Concerning the distribution of enteric pathogens throughout the year, our data demonstrate that rotavirus were rather shed during the months from January to April, adenovirus between April and August, Campylobacter during summer and Salmonella from July to October. The two thirds of Campylobacter and rotavirus infections and the half of adenovirus and Salmonella infections were identified during the ten first years of life. The highest prevalence occurs before 5 years old, during the 2nd year of life for adenovirus (4.4%) and rotavirus (22.3%) and during the 3rd year of life for Campylobacter (6.84%) and Salmonella (8.6%).

A systematic detection of Streptococcus pneumoniae strains with reduced susceptibility to penicillin has been realized at Limoges Hospital during two years half. Of 302 strains isolated, 27 had reduced susceptibility to penicillin (8,9%), and, for 15 strains (5%), the MIC of penicillin G reached at least 2 mg/l. The frequency of strains with reduced susceptibility to penicillin increased from 1992 to 1994: 8,2% in 1992, 8,7% in 1993 and 12,2% in 1994. The resistance level exhibited by pneumococcus strains increased since 1992: the percentage of resistant strains (MIC mg/l > 1) was 2,7% in 1992, 6,9% in 1993 and 7,3% in 1994. Most of the strains with reduced susceptibility to penicillin belonged to serotype 23 (52%) and were isolated from blood cultures, cerebral-spinal or pleural fluids (41%).

Prospective study on MRSA nasal cariage was done during two months in an intensive care unit in Limoges University Hospital. Nasal swab specimens were taken daily and cultured on selective and non selective media. Sixty eight patients were included in this study (878 swab collected, 575 MRSA isolated). Patients mean âge was 62 years and stay period mean was 12.3 days (median: 7 days). Among these patients, 16 were already carrying MRSA when entering in the unit and 26 became positive for MRSA during their stay. The mean colonisation delay was 5.5 days (median 4 days). All patients, except one, have shown a nasal carriage during all their stay. During the study period, 17 patients became infected and only two patients neither carried nasal MRSA before and during infection. In all cases, glycopeptide treatment did not affect nasal carriage. Colonisation and infection risk factors were discussed.

Macrolides are widely used in the treatment of respiratory infections. Here, the authors compared the activity of different 14-membered macrolides: erythromycin (Ery), roxithromycin (Rox), clarithromycin (Cla) and its 14-hydroxy metabolite 14-OH clarithromycin (14-OH) against 30 strains of Streptococcus pneumoniae isolated at the Dupuytren hospital (Limoges, France) from upper respiratory tract sputum, ophthalmic sputum, blood samples and CSF. Twenty strains were susceptible to macrolides and 10 were resistant. Three strains from the susceptible and 7 from the resistant were resistant to penicillin. Furthermore, for all the macrolides except Rox and 14-OH, susceptibility tests were performed by the disk diffusion method on Mueller-Hinton agar. MICs50 of Cla and Ery were 0.06 mg/l. They were two-fold increased for 14-OH (0.125 mg/l) and four-fold increased for Rox (0.25 mg/l). We noted that for 3 resistant strains, MICs of Cla were four-fold decreased than MICs of Ery. Ery, Cla and 14-OH had bactericidal activity against pneumococcus strains susceptible to these antibiotics at 4 and 8 times the MIC after 6 or 18 h. The difference between MIC and MBC was small (1 or 2 two-fold dilutions) for Ery, Rox and Cla. For 14-OH, this difference was within 2 to 4 two-fold dilutions. The bactericidal activity is similar to that of amoxicillin and cefotaxim. A microdilution chequeboard technique was used against 3 strains and the FIC index did not show synergistic effect of combining Cla and 14-OH. The activity of Cla and 14-OH against 5 strains was not modified in the presence of 50% fresh pooled human serum inactivated at 56 degrees C or not.

The diffusion of ofloxacin in infected and healthy human and rabbit eyes was investigated. In the human study, cataract surgery patients were given intravenous ofloxacin either as a single 200 or 400 mg dose or as two 400 mg infusions 12 hours apart. Samples of aqueous humor and plasma were collected between 1 and 12 hours after the end of the infusion. Levels in the anterior chamber increased with the dose; peak levels, which occurred after three hours, were 0.33 mg/l after 200 mg and 1.24 mg/l after two 200 mg doses given 12 hours apart. In the rabbit study, 16 hours after experimental infection of the left eye by injection of S. epidermidis into the vitreous, animals were given an intraperitoneal injection of 20 or 50 mg/kg ofloxacin. Dosages in the various ocular tissues showed that penetration into the eye varied with race (albinos greater than pigmented) and dose. Intraocular ofloxacin levels, including in the vitreous, increased two fold when the eye was infected; however, penetration into the sclera, choroid, and retina was comparable in infected and noninfected eyes. These findings in humans and animals suggest that ofloxacin in a dose of a least 400 mg is a useful agent for the treatment of prophylaxis of ocular infections.

Intraocular diffusion of piperacillin was studied in 42 patients scheduled for cataract surgery (n = 35) or vitrectomy (n = 7). Piperacillin was administered intravenously (4 g/injection). Thirty-four patients were given a single dose and 8 were given two doses 12 hours apart. Peak piperacillin levels in the aqueous (7.3 mg/l) occurred one hour after the injection; levels in the vitreous were low (less than 0.6 mg/l). Intraocular diffusion of piperacillin was also studied in rabbits with an experimental Staphylococcus epidermidis infection of one eye; the other eye served as the control. In pigmented rabbits (6 Fauve de Bourgogne animals), increased diffusion and decreased elimination of piperacillin were seen in the aqueous, iris and cornea of the infected eyes, as compared with uninfected control eyes. In albino rabbits (6 New Zealand animals), results were less conclusive, with a difference between the infected and healthy eyes appearing only during the second hour following the injection. The good diffusion of piperacillin in the aqueous, especially in infected eyes (at least in rabbits), suggests that this drug may be useful for the treatment of ocular infections provided it is initiated early and given in combination with another antimicrobial exhibiting good intraocular diffusion.