We studied the effects of biapenem (BIPM), meropenem (MEPM), and ceftazidime (CAZ) on the bacterial cell count and organ dysfunction in a rat sepsis model caused by Pseudomonas aeruginosa.
The sepsis model was established by infecting cyclophosphamide-treated rats with 10⁸ CFU of P. aeruginosa via intravenous Injection. Each of the antibiotics was injected subcutaneously 2 and 8 hours after infection. The bacterial cell count in the blood was determined 12 hours after infection. In order to evaluate of vital reaction in the infected animals, the parameters of organ dysfunction such as plasma lactate dehydrogenase (LDH), BUN, and GPT values were measured 12 hours after infection.
BIPM, MEPM, and CAZ had a significant therapeutic effect almost at the same level. BIPM showed a significant decrease in LDH as well, but MEPM and CAZ did not. Moreover, the effect of BIPM on elevated LDH values was significantly greater than that of CAZ. BIPM and MEPM showed a significant effect on the increases in GPT and BUN. None of these antibiotics had an effect on decreased WBC or platelet counts.
The results of this study showed that the therapeutic effects of carbapenems and cephems are almost equal with respect to improvement of organ dysfunction in the rat sepsis model caused by P. aeruginosa, and that carbapenems are superior to cephems. Moreover, the results suggested that the effect of BIPM on organ dysfunction is stronger than that of MEPM. In conclusion, the prognosis of sepsis caused by P. aeruginosa infection is better when carbapenems are chosen for treatment.

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We determined the MIC of 8 antipseudomonal agents against 160 Pseudomonas aeruginosa isolated from sputum at Hiroshima Prefectural Hiroshima Hospital from Feb. 1998 to Oct. 2002, and attempted to detect metallo-β-lactamase gene was tried to detect in Carbapenem resistant strains, with the follwing results:
1. Antibacterial activity was, in order of superiority to CPFX, MEPM, PZFX, IPM, CAZ, AMK, SBT/CPZ, PIPC.
2. Resistance to IPM was 21.3% and 13.8% to MEPM.(Resistance: I/intermediate and R/resistant)
3. Susceptibility of MEPM vs. 34 IPM resistant strains was I at 44.1% and R at 2.6%. Many strains showed cross-resistance to IPM and MEPM.
4. Metallo-β-lactamase-producing strains were not detected.
5. Multiresistant P. aeruginosa strains (MIC of IPM ≥16 μg/mL, CPFX 4μg/mL, and AMK≥32 μg/mL) were not detected.
6. Susceptibility of P. aeruginosa isolated from sputum developed resistance mainly to carbapenems. The appropriate use of antibacterial agents and monitoring of susceptibility patterns should be taught

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A pilot study of CZOP for the indication of febrile neutropenia (FN) according to the Japanese guidelines was conducted in patients with hematological disorders.
Forty-four patients (43 evaluable), mainly with leukemia or lymphoma, entered in to the study. The response rate on days 3, 4, 5, 6, 7 after the start of CZOP administration was 27.3%, 32.6%, 39.5%, 48.8%, and 62.8%, respectively. Significant differences in response rate were observed between patients with sustained neutropenia below 100 for<4 days and for>5 days. There was no mejor difference in the response rate of the patients whether judged by the Japanese criteria or the American criteria. The Japanese guidelines were concluded to be valid, and CZOP is considered promising for the indication of FN.

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A 89-year-old woman was found to have a high-grade fever. Escherichia coli were isolated in cultures of blood, urine, and feces. The result of antibiotic susceptibility against the isolates was predicted the presence of Extended spectrum β-lactamase (ESBL)-producing strain. We switched the antibiotics to imipenem (IPM) and fosfomycin (FOM). But, the patient developed a drug-induced exanthema as an adverse effect of IPM, however, and intravenous administration of FOM alone was continued for 2 weeks. FOM was effective, and the fever and abnormal laboratory findings improved immediately. The result of the sequence analysis of the ESBL revealed that the β-lactamase was UOE-1. The Not I restriction patterns of the chromosomal DNA of the pulse-field gel electrophoresis showed that the isolates from blood, urine, and feces were identical. We concluded that the urosepsis had developed as a result of urinary tract contamination by feces.

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A highly penicillin-resistant strain of Streptococcus pneumoniae, isolated in the Republic of Korea in 1997, was identified in detail on the basis of its phenotypic and genotypic features. The strain had been identified as Streptococcus pneumoniae based on its α-haemolytic activity and optochin susceptibility. However, the results of further study showing that it was negative for the lytA. gene by PCR and the API-Strep results showing that it was an oral streptococcus, suggested that the strain was an oral streptococcus and not Streptococcus pneumoniae.
This finding indicates that the genotype as well as the characteristic phenotype must be checked to accurately identify Streptococcus pneumoniae.

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