In conjugational crosses, three Klebsiella pneumoniae strains and one Serratia marcescens strain have been demonstrated to transfer resistance determinants to newer types of cephalosporins. While Klebsiella strains donated cefotaxime, cefamandole and cefuroxime resistance to Escherichia coli K-12 recipients, the genetic analysis of exconjugants after the transfer of plasmids from Serratia strains to Proteus or Salmonella recipients showed that the cefoxitin resistance determinant was also co-transferred. In subsequent transfer cycles of this plasmid, cefotaxime and cefoxitin resistance determinants segregated in contrast to the relative stability of plasmids derived from Klebsiella strains in subsequent transfer cycles. From results obtained in this study, it may be concluded that in some strains of nosocomial Enterobacteriaceae, resistance to newer cephalosporins could be transmissible and thus plasmid-located.

In order to assess the diagnostic value of procalcitonin, 158 patients with febrile neutropenia from centres across Europe were studied. Patients with fever were diagnosed on the basis of either: (1) clinical, radiological and microbiological criteria; or (2) the procalcitonin value. In the latter case, concentrations of 0.5-1.0 ng/mL were considered diagnostic of localised infection, concentrations of 1.0-5.0 ng/mL of bacteraemia, and concentrations of > 5.0 ng/mL of severe sepsis. Procalcitonin and C-reactive protein were estimated daily in serum by immunochemiluminescence and nephelometry, respectively. Overall, the sensitivity (specificity) of procalcitonin for bacteraemia was 44.2% (64.3%) at concentrations of 1.0-5.0 ng/mL, and 83.3% (100%) for severe sepsis at concentrations of > 5.0 ng/mL. It was concluded that procalcitonin is a marker strongly suggestive of severe sepsis at concentrations of > 5.0 ng/mL. Estimated concentrations of < 0.5 ng/mL indicate that infection is unlikely, but it was observed that bacteraemia associated with coagulase-negative staphylococci may fail to elevate serum procalcitonin levels.

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Bi-resistance to high concentrations of gentamicin and carbenicillin began to appear in strains of Pseudomonas aeruginosa from the urine of patients in several clinics and stations of our area. Nine out of 142 ‘urine strains’ of Ps. aeruginosa isolated from July to November 1971 are highly resistant to the above-mentioned antibiotics and also to others. Four additional strains appeared to be highly resistant to carbenicillin only, retaining their relative susceptibility to gentamicin. Transfer of both G^R and Ca^R determinants to E. coli K₁₂ recipient strains, however, did not take place. Thus, rifampicin-resistant high-level mutants of four G^SCa^S wild type strains of Ps. aeruginosa were obtained and used as recipients for both G^R and Ca^R determinants. Three bi-resistant G^RCa^R strains (No. 138, 140 and 110) transferred G^R determinants to individual Ri^R recipients, but none transferred Ca^R. The transfer was inter-strain specific and no general recipient mutant was so far obtained.

Conjugal transferability of drug resistance was examined, in eleven Pseudomonas aeruginosa strains which were isolated in Frankfurt. Four R factors were demonstrated from three strains using P. aeruginosa as recipients but they were nontransferable to Escherichia coli K12. Two R factors, i.e., Rms146 and Rms147, mediated resistances to tetracycline (TC), streptomycin (SM), sulfanilamide (SA), kanamycin (KM), lividomycin (LV), gentamicin C complex (GM) and 3′,4′‐dideoxykanamycin B (DKB). They mediated the formation of aminoglycoside‐inactivating enzymes, i.e., SM phosphotransferase, SM adenylyltransferase, KM and LV phosphotransferase 1, and GM and DKB 6′‐N‐acetyltransferase. TC resistance conferred by these R factors was due to impermeability of the drug. P. aeruginosa Ps 142 carried two kinds of R factor in one cell, Rms148 (SM) and Rms149 (SM·SA·GM·CPC) (CPC, carbenicillin). Rms148 (SM) was transferable at a high frequency of 10–1 and mediated the formation of SM phosphotransferase. Rms149 mediated the formation of drug‐inactivating enzymes, i.e., GM 3‐N‐acetyltransferase and β‐lactamase, but did not inactivate SM. SM resistance was probably due to impermeability of the drug.