[Frequency and antibiotic susceptibility of oxacillin resistant Staphylococcus aureus in a teaching hospital]. / Häufigkeit und Antibiotikaempfindlichkeit von Oxacillin-resistenten Staphylococcus aureus-Stämmen in einem Lehrkranhaus.

From October 1993 till October 1994, 115 oxacillin resistant Staphylococus aureus strains were isolated in the laboratory of a teaching hospital. This was 2.4% of all of the Staphylococcus aureus strains. The bacteria were isolated from 30 patients, 7 medical personnel and in the environment of the infected patients. Most of the isolates were cultured from blood cultures, wound swabs and drains. If the referring hospitals has been informed about the MRSA status of the patients, several transmissions could have been prevented. In 10 infected patients, the MRSA strains were isolated from the nose, throat and hands. The isolates were also found on the hands of several personnel and in the patients environment, suggesting that the strains had been widely spread. The MRSA strains predominated in the medical and surgical intensive care units and in 2 general surgical wards. They were only found sporadically in other departments (Ophthalmology, Gynaecology, Paediatrics and Urology). MRSA-strains were more resistant to imipenem, ofloxacin, gentamicin, trimethoprim-sulfamethoxazole, tetracycline, erythromycin and clindamycin as oxacillin-sensitive Straphylococcus aureus strains. Genotyping (Restriction-Fragment-Length-Polymorphism) revealed six different strain patterns. The same RFLP types were mainly found on different wards. We conclude that various clones of MRSA may have emerged independently within one hospital and that their spread between wards was remarkably limited. Subsequent intensive hygiene measures have been successful in reducing the number of new isolates.

Isolation of a Bordetella avium-like organism from a human specimen.

The isolation of a strain of Bordetella for which the species could not be determined but which most closely resembled Bordetella avium is reported. The strain was isolated in mixed culture from an ear swab of a patient suffering from chronic otitis media. The bacterium showed the typical biochemical reactions of Bordetella avium but differed in antimicrobial resistance pattern, protein and fatty acid composition, and DNA-DNA and DNA-rRNA hybridization. Further studies will clarify the taxonomic status of this strain within the Bordetella-Alcaligenes ribosomal RNA cluster.

[Nosocomial colonization and infection by multiresistant Enterobacter cloacae strains on a pediatric oncological unit]. / Nosokomiale Kolonisation und Infektion durch multiresistente Enterobacter cloacae-Stämme auf einer onkologischen Kinderstation.

A multiresistant E. cloacae strain spread during a six month period in a paediatric oncology ward amongst nine children, who had different tumors and malformations. Three children who had shared a room were especially affected. E. cloacae was isolated 122 times from the children with tumors and five times from their environment. Specimens from which the bacteria were isolated, included blood cultures, catheter tips, wound swabs, drains, skin and mucous membranes from most parts of the body. The majority of the E. cloacae strains were resistant to ampicillin, mezlocillin, piperacillin, azlocillin, doxycycline and cephalosporins of the second and third generation and sensitive to imipenem, aminoglycosides and quinolones. The antimicrobial resistance patterns of the E. cloacae strains from the paediatric oncology ward were compared to those isolated from other wards in the hospital. E. cloacae isolates from the intensive care unit had a reduced sensitivity to beta-lactam antibiotics, whereas the isolates from the other wards were, with the exception of ampicillin, sensitive to beta-lactam antibiotics. The analysis of the E. cloacae strains from the paediatric oncology ward revealed the same antimicrobial resistance pattern, bacteriocin type, RFLP-type and an identical enzyme and whole cell profile. Isolates from other wards showed considerably deviating patterns. The systematic registration and isolation of patients, colonized or infected with multiresistant E. cloacae strains, together with infection control methods, lead to a significant reduction in infections.