RESUMEN
BACKGROUND: Neisseria animaloris and Neisseria zoodegmatis, former CDC Group EF-4a and -4b, are considered to be rare zoonotic pathogens, usually associated with dog or cat bites. The aim of the study was to phenotypicaly characterize 13 EF-4 isolates from wound infections, determine their antibiotic susceptibility and to follow the clinical outcome of the patients. METHODS: 13 of the EF-4 isolates were cultured on agar plates. Conventional biochemical tests and the Biolog system were used for phenotypical identification. An arbitrary primed polymerase chain reaction (AP-PCR) was carried out to determine the genetic profiles. Minimum inhibitory concentration (MIC) values were determined for different antibiotics were determined. According to this, clinical data for the patients were recorded. RESULTS: 11 isolates were identified as N. animaloris and 2 as N. zoodegmatis due to the production of arginine dihydrolase. A majority of the patients had a history of dog bite. In 6 cases only grewth of N. animaloris or zoodegmatis was registered. When a patient received antibiotic treatment the most common drug of choice was penicillin V. Only 3 patients received treatment for which the isolated EF-4 bacterium was fully susceptible. CONCLUSION: Human infections involving N. animaloris and N. zoodegmatis usually present themselves as local wound infection, but severe complications can occur. Despite their pathogenic potentia, l N. animaloris and N. zoodegmatis are often misidentified, dismissed as skin contaminants or not recognized at all. Due to the fact that N. animaloris and N. zoodegmatis are significant pathogens in animal bites, physicians should keep these bacteria in mind when choosing antibiotic therapy.
RESUMEN
Since 1986, 68% of the Listeria monocytogenes isolates from human cases of invasive listeriosis in Sweden are available for retrospective studies. The aim of the present study was to characterize 601 human invasive isolates of L. monocytogenes in Sweden from 1986 to 2007 by using serotyping and pulsed-field gel electrophoresis. Since 1996, serovar 4b was permanently reduced to the second or third most common serovar in human cases in Sweden. During the latter period, 2000-2007, only 13% belonged to serovar 4b and 71% to 1/2a. The dendrogram, based on pulsovars, reveals two clusters with different serovars. Cluster 1 exhibits serovars 4b and 1/2b, whereas cluster 2 consists of serovar 1/2a. Serovar 1/2a seems to be more heterogeneous than serovar 4b.