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Coagulase-negative staphylococci (CoNS), particularly Staphylococcus epidermidis, are increasingly being recognized as opportunistic pathogens. They are often multiply antibiotic resistant and can cause nosocomial outbreaks. For clinical and epidemiological reasons, accurate species identification and typing are imperative. Ribotyping, i.e., the generation of characteristic fragment patterns by hybridization of restriction endonuclease fragments of total DNA with labeled standard rRNA from Escherichia coli, has been applied to CoNS for species identification by various investigators. The present study, involving 115 randomly collected clinical isolates of CoNS, provides ambiguous evidence with respect to those findings. Eighty six S. epidermidis strains were ribotyped intraspecifically. Eleven different ribotypes were found after digestion with EcoRI, and 10 were found with HindIII. A combination of the two restriction endonucleases resulted in an increase in the discriminatory power (DP) from 14.3 to 31.6%. A combination of ribotyping with biotyping raised the DP to a maximum of 48.6%. The reproducibility of ribotyping was 100% after greater than 400 generations of growth. No correlation between methicillin resistance and certain ribotypes among the S. epidermidis strains was observed. Ribotyping is considered a useful tool for the intraspecific typing of CoNS for epidemiological purposes. The DP can be increased by the use of additional restriction endonucleases.

A case is reported of a male adult withHaemophilus influenzae type b septicaemia and subsequent abscess in the left thigh due to this microorganism following injection of phenylbutazone. The phenylbutazone probably caused muscle cell damage. It is assumed thatHaemophilus influenzae type b colonized the site during an episode of septicaemia, with subsequent development of necrosis and abscess.

Although systemic infections withPasteurella multocida rarely occur in humans, liver cirrhosis associated with septicemia due to this organism has been frequently reported. Two cases of elderly women withPasteurella multocida septicemia are described who had diabetes mellitus and breast cancer, respectively. Underlying diseases other than liver cirrhosis as well as factors hitherto unknown in otherwise healthy persons also enhance the risk ofPasteurella multocida septicemia.

Recurrent contamination of bacteriological specimens withCandida parapsilosis led to epidemiological investigations which indicated persistent colonization of carbon dioxide incubators as the most likely source. Changes in the technical arrangements and institution of a meticulous cleansing protocol eliminated contamination of specimens but not colonization of the incubators. Tests for tolerance of 17 % NaCl and survival at 50 °C, and SDS-PAGE analysis of crude cell extracts allowed discrimination between epidemic and non-epidemic isolates, while enzyme profile analysis and susceptibility studies failed as typing methods.

Summary The author reviews the data available on endotoxins ofFusobacterium, Sphaerophorus, Leptotrichia, andVeillonella species, and reports his own findings with lipopolysaccharides extracted fromBacteroides fragilis strains by the trichloroacetic acid method. The latter extracts showed a very low toxicity for mice after i. v. injection of dosages of =500 µg and a slight leucopenic effect in mice after intraperitoneal injection of 50 µg.

None of 50 healthy individuals and only 2 of 50 hospitalized patients (with Acinetobacter anitratus elsewhere) yielded A. anitratus on enrichment from fecal samples.