Diagnostic des légionelloses

Legionellosis has three distinct forms: Legionnaire's disease, the more severe form of infection wich includes pneumonia, extrapulmonar legionellosis forms, and Pontiac fever, a milder illness. About 15% to 20% of known cases of Legionnaire's disease have been fatal. Delay in instituting appropriate therapy for Legionella pneumonia significantly increases mortality underlining the need for a rapid diagnosis. The distinction between Legionnaire's disease from other types of pneumonia by symptoms alone is not easily done. The diagnosis of legionellosis requires specialized laboratory tests not routinely performed on patients with fever and pneumonia. The definitive method is culture of Legionella but the growth of the organism is fastidious. Direct fluorescent-antibody staining is a rapid diagnostic test with a low sensitivity. The Legionella urinary antigen assay is a rapid test which detects only antigens of L. pneumophila serogroupe 1 in urine. Serologic tests are useful and necessite to evidence the increase of the antibody titers to Legionella in two blood samples obtained 3 to 6 weeks apart. It is a tardif diagnosis. Assays based on the polymerase chain reaction (PCR) have been used to detect Legionella in urine samples, bronchoalveolar-lavage fluid and serum. The primary advantage of this technique is the ability to detect Legionella rapidly and species other than L. pneumophila.     

Diagnostic des cervicites bactériennes

Bacterial endocervitis or true cervicitis result from the damage of the columnar, glandular epithelial cells of endocervix by the two sexually transmitted bacteria, Chlamydia trachomatis and Neisseria gonorrhoeae. The lack of specific clinical features of endocervical infections does not permit an accurate etiologic diagnosis without laboratory assistance. The conventional laboratory diagnosis of C. trachomatis et N. gonorrhoeae relies primarily on isolation in culture, but this procedure is not always easily achievable. More recently, nucleic acid amplification technologies using PCR have been developed, and are considered as more sensitive than culture for detection of C. trachomatis, particularly in asymptomatic endocervical carriage. Multiplex PCR detecting both pathogens from a single specimen would provide a cost effective way of screening symptomatic and asymptomatic individuals for C. trachomatis and N. gonorrhoeae.     

Méthodes d'évaluation in vitro des antigfongiques: étude comparative des différents tests

Since few years, we see an increasingly large population of immunocompromised patients. The result is the selection of fungi with primary and secondary resistance and the emergence of new species. So, antifungal agents are more used and it was necessary to developp usually antifungal drug suceptibility testing. Deep antifungal agents are following : amphotericin B, 5-fluorocytosine, ketoconazole, fluconazole and itraconazole.A National Committee Clinical Laboratory Standards Methods (NCCLS M27 document) has been developped for a performed interlaboratory reproductibility. Further progress has been achieved with determination of interpretive break points. It is important that commercial systems performed according to NCCLS recommandations as E-test® (AB Biodisk) and Fungitest® (BioMérieux).E-test® is superior in its ability to detect amphotericin B resistance but the interpretation of end points is not easy. Fungitest® is able to detect sensitive strains but has a poor capacity to detect resistant strains. The recent approval of a reference method is encouraging but it is not recommended that antifungal suceptibility testing be performed as a matter of routine.     

Importance médico-vétérinaire des puces de notre environnement

Fleas are essentially mammalian ectoparasites and are as such often in more or less direct contact with man, especially the synantrope fleas. These insects of medical and veterinary interest are the cause of direct (bites) and indirect (disease transmission) nuisance. This paper gives an overview of the main species observed in France, outlines easy identification methods, lists the nuisance caused by each of the species presented and describes the control methods.