The drug-resistance patterns and plasmid profiles of 147 isolates (patient origin 142 and food origin 5 isolates) from the outbreak of enterohemorrhagic Escherichia coli (EHEC) O157: H7 infection in Obihiro-city Hokkaido in late October, 1996, were examined. Thirty-six isolates were resistant to tetracycline (TC) (24.5%), 15 of which were resistant to both streptomycin and TC. The minimal growth inhibitory concentration (MIC) of fosfomycine (FOM) was examined, confirming that MIC changed by the cultivation conditions, that is 12.5μg/ml at the aerobic condition, 1.6μg/ml at the anaerobic condition and 3.2μg/ml on blood agar plates. Furthermore, though E. coli O157 could not be detected once by the FOM medication, FOM sensitivity of the patient origin O157 isolates who became O157-positive again was examined. Any changes in FOM sensitivity were not observed. Plasmid profiles of all isolates were divided by 4 patterns from A to D. The most dominant pattern was type A, and plasmid profiles of food origin O157 belonged to pattern A. In 9 examples of the person-to-person infection in the family, plasmid patterns of O157 isolates were the same to each other, even though drug-resistant patterns were different. In 13 patients developing the duration of excretion of EHEC, the changes of the drug-resistance patterns were correlated with the changes of plasmid profiles. By comparing plasmid profiles and TC resistance, it was suggested that TC resistance was controlled on a plasmid. Since food origin O157 isolates were sensitive to all drugs and presenting the same plasmid profiles, demonstrating that TC resistance and plasmid are newly added to the bacterial cells while food origin O157 isolates passe inside the human body.

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The clinical isolates of Pseudomonas aeruginosa can be roughly classified into long-and short-lipopolysaccharide (LPS) strains and LPS-deficient strains, based on the silver-stained patterns of their LPSs after SDS-PAGE.
The ionic binding of 3H-gentamicin, a polycationic antibiotic, to the negatively charged sites on the surface structures of P. aeruginosa strains, often differing in LPS structure, was the highest in the long-LPS strains followed in descending order by the short-LPS strains and LPS-deficient strains. It was presumed that a clinical isolate of P. aeruginosa No.45 is lacking in the O-polysaccharide chains and some structures of the core-regions consisting of its LPSstructure after SDS-PAGE. On the other hand, the binding of 3H-gentamicin to this strain was quite. high, i.e., similar to that to of the long-LPS strains. To clarify this finding, P. aeruginosa PAC1R and its LPS-deficinet mutants were used as reference strains because the chemical structures of their LPSs containing the repeated units of O-polysaccharides and the neutral sugar contents in the core-regions were previously confirmed.
The PAC605 strain of the LPS-mutants of the PAC series, was completely lacking in the repeated units of O-polysaccharide and also lacking in some neutral sugar residues of the core-oligosaccharide region. However, this strain was highly bound to 3H-gentamicin, suggesting that the negatively charged sites on the deep core-oligosaccharide region and/or on lipid A participated in the binding of 3H-gentamicin. This manner of binding may be also applied to P. aeruginosa No.45.
When P. aeruginosa PAC1R, PAC605 and No.45 strains were each exposed to gentamicin (20μg/ml) for 10 minutes, the viable cell counts of PAC1R decreased to about 70% of the initial count, whereas the viable cell counts of PAC605 and No.45 strains decreased to 3.6 and 11.0%, respectively, indicating the vulnerability of both types of the strains to be enhanced by the bactericidal action of gentamicin with short-term incubation.

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Fungi were isolated from 642 cases (3.5%) of 18, 403 blood samples at Teikyo University Hospital during the 17-years period between 1979 and 1995. The number of fungemia cases began to increase around 1985, reached a peak in 1988, and since then, it has been gradually decreasing.
The fungal species of isolates were:(1) Candida albicans in 224 cases (34.9%), (2) C. parapsilosis in 149 cases (23.2%), (3) C. tropicalis in 87 cases (13.6%), (4) C. glabrata in 65 cases (10.1%), (5) Hansenula anomala in 58 cases (9.0%), (6) C. guilliermondii in 24 cases (3.7%), (7) C. famata in 14 cases (2.1%), (8) Trichosporon beigelii in 11 cases (1.7%), (9) C. inconspicua in 5 cases (0.8%) and C. lusitaniae in 5 cases (0.8%), and other yeasts in 33 causes (5.1%). The number of isolates of C. albicans has been decreasing since 1989, concomitant with the clinical introduction of fluconazole in this hospital. However, the number of fluconazole-insusceptible fungi such as non-albicans Candida and Trichosporon spp. has increased.
Fungemia cases infected concomitantly or sequentially with two or more different fungal species have been found occasionally since 1983 and have shown a high mortality rate.
The spectrum of the causative organisms of fungemia appears to be, at least, partly influenced, by the usage of antifungal agents, particularly fluconazole.

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The detection of Helicobacter pylori in gastric aspirate was examined by using the polymerase chain reaction (PCR) method for amplifying a specific fragment of the urease gene A. The ability of PCR to amplify H. pylori-specific DNA was analyzed by Southern hybridization with an internal oligonucleotide probe. Twenty-two H. pylori strains from clinical isolates and reference strains were studied, and all H. pylori strains yielded a 356-bp product that hybridized with the oligonucleotideprbe, whereas no amplification was evident with 18 non-H. pylori strains. This could detect as litle as 50 CFU of H. pylori in pure culture and 0.1 pg of purified chromosomal DNA. A total of 50 dyspeptic patients were examined for the presence of H. pylori by culture, the rapid urease test and histological examination of antral biopsy samples as well as by PCR in gastric juice aspirate samples. The gold standard for the presence of H. pylori was established by minimum concordance of two of three tests performed on biopsy specimens. With this gold standard, 34 of the 50 patients were considered to harbor H. pylori infection. PCR correctly identified 32 (94.1%) of these 34 infected patients. PCR had the best combination of sensitivity and specificity in assessing the correct diagnosis of H. pylori as compared with those of the rapid urease test and culture. Moreover, we extablished a fast and simple method for use by improvement of DNA extraction. PCR of the gastric aspirate was shown to be a sensitive and specific procedure which may be an attractive alternative to methods currently used for diagnosis of H. pylori infection.

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We reviewed our experience with terminal stage infections in patients with lung cancer over an 11 year period at Kurume University Hospital. In patients with end-stage lung cancer, the infection is common and a mortal disease. We examined the clinical features and significance of pathogenic microbes isolated from sputum and blood in patients with lung cancer during their last month.
Bacteriological examinations from blood done frequently in patietns with episodes of fever revealed that bacteremia was one of the most important disease in terminal stage infection. In the blood cultures from the 22 patients various species of pathogenic microbes were recovered, and nine of which were fungi; five Candida albicans, three Candida tropicalis and one Candida parapsilosis. The major species of bacteria isolated from sputum were Staphylococcus aureus, including methicillin-resistant strain, and Gram-negative bacilli; P. aeruginasa, A. calcoaceticus, K. pneumoniae and E. cloacae, which are known to be frequently involved in hospital-acquired infections. However, S. pneumoniae and H. influenzae which were well known to be microbes of respiratory infections were rare.
We concluded that we had to reveal the feature of terminal stage infection in order to reduce the fee for medical treatment and improve the QOL of patients with terminal stage lung cancer.

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The utility of ¹¹¹In-DTPA-IgG imaging for the detection of intrathoracic lesions was evaluated in 10 patients with the suspicion of inflammatory or infectious diseases. They were intravenously administered 40 or 80 MBq of ¹¹¹In-DTPA-IgG, and scanned after 24 or 48 hours.
Of these, 8 cases, consisted of 4 cases with pneumonia and 2 cases with lung abscess and one case of pulmonary teberculosis and one of a tuberculous pleuritis, showed true positive results. Others were one false negative case of pneumonia and one true negative case of lung cancer. Overall sensitivity and specificity were 88.9% and 100%, respectively. There were no cases which showed side effects or abnormal laboratory findings caused by the radiopharmaceuticals administered. Thus, ¹¹¹In-DTPA-IgG imaging is a useful tool for the detection of intrathoracic infectious lesions.

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The surveillance of acute hemorrhagic conjunctivitis (AHC) caused by enterovirus 70 (EV70) is insufficient because of the difficulties of virus isolation using conventional methods.
In this study, reverse transcription-polymerase chain reaction (RT-PCR) and stringent microplate hybridization (SMH) methods were assessed for the detection of EV70 in conjunctival swabs collected from the patients of AHC which broke out in Miyazaki Prefecture in 1990 and Okinawa Prefecture in 1994.
Furthermore, with the use of the SMH method, we compared the genetic homogeneity of EV70 detected from the samples collected in 1990 and 1994 to the J670/71 strain isolated approximately 25 years ago. A similar investigation was performed between recent coxsackievirus A24 variant (CA24v) and EH24/70 strain, a standard strain of CA24v that was isolated approximately 25 years ago approximately 25 years ago.
As a result, RT-PCR products were detected in 26 of 34 conjunctival swabs collected in Miyazaki Prefecture in 1990. Likewise, RT-PCR products were detected in 9 of 10 conjunctival swabs collected in Okinawa Prefecture in 1994, and these RT-PCR products were all identified as EV70 by SMH method. Such a high level of virus recovery from specimen shows the evidence of usefulness of these techniques.
Recent EV70 showed a reaction of about 60% to a probe synthesized with J670/71. Likewise, recent CA24v showed a reaction of about 30% to a probe synthesized with EH24/70. These finding are highly suggestive of the progress of viral mutation.

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A 25-year-old male, who had returned from the Republic of Mali in Africa, was admitted to our hospital because of a 3-day history of high fever, on the first of October 1996. He was diagnosed as Plasmodium falciparum malaria by peripheral blood smear. From the admission day he was treated with quinine HC1, 1, 500 mg per day, and sulfamethoxazole 2, 400 mg trimethoprim 480 mg per day, but on October 2nd blood examination showed 35%0 parasite density and he was given mefloquine. However he was complicated with DIC on October 3rd, ARDS on October 5th. By anti-coagulant therapy and methylprednisolone pulse therapy he became afebrile and respiratory function improved rapidly. ARDS should be emphasized as a severe complication of imported severe malaria.

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We reported a case of tuberculous pyothorax which developed at four years after finishing with the first treatment for pulmonary tuberculosis.
A 50-year-old female was admitted to our hospital with right chest pain. Tuberculous pyothorax was diagnosed by means of polymerase chain reaction (PCR method) of pleural effusion and of histological findings of the pleural section. She was cured by operation, pleural drainage and anti-tuberculous drugs. The bone scincigram of ^99mTc revealed accumulation in the right 9th rib, tuberculous empyema might have been a secondary development from osteomyelitis.

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[in Japanese]

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Retropharyngeal abscess is reported to be decreasing in frequency in recent years. We report two cases of retropharyngeal abscess that were diagnosed within four years in Department of Otorhinolaryngology, Gifu University Hospital. Case 1 was a 36-year-old male who was suggested to have an abscess as primary infection and case 2 was a 71-year-old female whose abscess seemed to be a secondary infection following unknown primary infection. Endoscopic or open neck drainage as well as antibacterial chemotherapy mainly with combinations of flomoxef and clindamycin in the case 1 and piperacillin and clindamycin in the case 2 was successfully carried out. They were discharged an 15-day and 24-day after operation in the cases 1 and 2, respectively. A 30 min. culture after sample collection on operation demonstrated aerobe-anaerobe mixed infection in both cases; three aerobes and four anaerobes in the case 1 and three aerobes and two anaerobes in the case 2. These results suggest that retropharyngeal abscess may be a complicated infection involving more bacterial species than has been commonly believed. Measuring susceptibility of isolates to antimicrobial agents, a strain of Capnocytophaga sp. and a strain of anaerobic gram-negative rod were highly resistant to piperacillin, cefroxine and ofloxacin. It is important for adequate antibacterial chemotherapy to grasp the bacteriology of retropharyngeal abscess and analyze susceptibility of antimicrobial agents.

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[in Japanese]

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