Staphylococcus epidermidis is a common cause of catheter-associated infections and septicemia in immunocompromised patients. To answer the question whether S. epidermidis skin isolates differ from isolates causing septicemic diseases, 51 strains obtained from blood cultures, 1 strain from shunt-associated meningitis, and 36 saprophytic isolates were characterized. The study demonstrates that most of the blood culture strains formed a multilayered biofilm on plastic material, whereas skin and mucosal isolates did not. Moreover, biofilm-producing strains were found to generate large bacterial autoaggregates in liquid culture. Autoaggregation and biofilm formation on polymer surfaces was associated with the presence of a DNA sequence encoding an intercellular adhesion gene cluster (ica) that mediates the production of a polysaccharide intercellular adhesin. The presence of the intercellular adhesion genes in blood culture isolates was also found to be correlated with the exhibition of black colonies on Congo red agar, whereas the adhesin-negative strains formed red colonies. Upon subcultivation on Congo red agar, the black colony forms of the blood culture strains exhibited red colony variants which were biofilm and autoaggregation negative and occurred at a frequency of 10 ؊5. The DNA analysis of these S. epidermidis variants by pulsed-field gel electrophoresis and Southern hybridization with an ica-specific gene probe revealed no detectable difference between the black and red colony types. Moreover, after repeated passage, the phenotype of the parent strain could be restored. Therefore, these colony forms were regarded as phase variants. This phenotypic change was observed exclusively in adhesin-positive clinical isolates and not in adhesin-negative saprophytic strains of S. epidermidis.

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Background. There is a discrepancy between the incidence of gastrointestinal involvement by malignant lymphomas, as established in postmortem studies, and the rareness of the corresponding clinical diagnosis. Methods. Therefore, the authors performed routine upper gastrointestinal endoscopic examination, within the framework of the usual staging examinations, in 103 consecutive patients with newly diagnosed Hodgkin disease (n = 21) and non‐Hodgkin lymphoma (n = 82). Results. One patient with Hodgkin disease (4.8%), 11 of 40 patients (27.5%) with non‐Hodgkin lymphoma of low‐grade malignancy, and 11 of 42 (26.2%) of those with highly malignant non‐Hodgkin lymphoma showed involvement of the gastric and/or duodenal mucosa, as diagnosed with esophagogastroduodenoscopy. Of the 22 patients with non‐Hodgkin lymphoma, 9 had involvement of other mucosa‐associated lymphoid or epithelial tissue. In two patients with Stage III, two with Stage II, and two patients with presumptive Stage I disease, the disease was reclassified as Stage IV. Because of gastrointestinal involvement, treatment for two patients was changed from radiation therapy to chemotherapy and another two patients had gastric resections so that possible treatment‐related complications could be avoided. Conclusions. In light of these results and the fact that a major basis for the therapeutic strategy for malignant lymphomas is tumor stage, routine esophagogastroduodenoscopic examination within the framework of the usual staging examinations is recommended. In individual cases, this procedure may be of decisive importance in the therapeutic approach to and prevention of complications.

The hepatobiliary pharmacokinetics of mitoxantrone, a new anthracenedione derivative, was studied in the isolated perfused rat liver. Mitoxantrone was administered in doses of 0.2 and 0.4 mg/kg body weight. Multiple bile samples were obtained for 4 hours. Mitoxantrone and three metabolites were separated by high-performance thin-layer chromatography (HPTLC) and measured at 610 nm. Following 0.2 mg mitoxantrone/kg body wt, 25.8% +/- 2.6% of the administered dose was excreted in the bile during 4 h, the major metabolite M1 accounting for 80% of this. After 0.4 mg mitoxantrone/kg body wt the amounts excreted were lower and light microscopic examination showed disseminated areas of cell necrosis.