Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most important microorganisms in nosocomial infection. Healthy medical staff working in MRSA endemic wards are known to have MRSA in their nasal cavity, swabs, but the significance of their positive nasal swab cultures in infections among the patients has not been confirmed. The purpose of this study was to compare the antibiotic susceptibility and coagulase typing of strains isolated from the infected patients and from nasal swab cultures of medical staff working in ICU.
Twenty-six nurses and 20 doctors working in ICU where MRSA was endemic were examined. Six nurses and 10 doctors gave positive nasal swab cultures for S. aureus, and 2 of the nurses' strain and 5 of the doctors' strains were methicillin-resistant. These strains were sensitive to IPM, GM, MINO and OFLX, while the strains clinically isolated from infected patients were resistant to these antibiotics. MRSA isolated from nasal swab cultures from medical staff developed marked resistance to IPM, GM, MINO, and OFLX by incubating with these drugs, whereas they remained sensitive to VCM when they were incubated in VCM-containing medium. Methicillin-sensitive S. aureus (MSSA) isolated from nasal swab cultures of medical staff became resistant to DMPPC, CMZ, in addition to IPM, GM, MINO, and OFLX, but these strains did not develop resistance to VCM. Resistance to these drugs developed by incubating with these drugs did not diminish by incubating in drug-free medium for 3 weeks. The patients infected by MRSA had been previously given several kinds of antibiotics, whereas the medical staff had not been exposed to any kind of antibiotics during the same period.
The coagulase typing of the MRSA isolated from medical staff and patients were all II. The coagulase typing of the MSSA from the medical staff were II, III, or VII. The distribution pattern was similar to the MSSA clinically isolated from in-patients, but different from the MSSA isolated from out-patients.
These findings raise the possibility that both MRSA and MSSA as carried by the medical staff may be a source of the nosocomial infection of hospitalized patients.

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To investigate the role of BALT in chronic respiratory infection, we established a rat model of chronic bronchiolitis caused by Pseudomonas aeruginosa, and the light microscopic findings of the BALT were studied.
Experimental pneumonia was produced in SD rats by intratracheal inoculation of 10⁶ colony forming units (cfu) of mucoid P. aeruginosa enmeshed in agar beads. The mean cfu recoverable from the lung increasd up to 10⁸ cfu at day 1. The number of bacteria remained fairly constant at 10⁴ cfu until day 28. Histologically, infiltration of neutrophils could be seen around the agar beads containing P. aeruginosa in the lung from day 1 to day 7. From day 14 to day 28. the histological changes in the lungs were characterized by accumulation of foamy cells accompanied with lymphocyte infiltrations and granulation tissues around the respiratory bronchioles, but without involved alveoli. These chronic inflammatory histologic changes were similar to those of diffuse panbronchiolitis (DPB). At the same, time, there were massive accumulation of lymphocytes in lymphatics and in high endothelial venules of the BALT at day 7. The development of germinal centers in the follicular area was found from day 7 to day 28. The airway was narrowed as a result of BALT hyperplasia protruding to the bronchial lumen.
These results suggest that histological changes represent the model of chronic bronchiolitis and BALT may have a specific role in developing the local immune responses against chronic respiratory infection due to P. aeruginosa.

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An outbreak of pertussis occurred in one room of a residential facility where 19 children aged 5 to 36 months were residing. They were prospectivelly surveyed to estimate the efficacy of acellular pertussis vaccine. Among the 19 residents, 9 were immunized with acellular pertussis vaccine. Among the 19 residents, 9 were immunized with acellular DTP vaccine and 10 were unimmunized. The spread of pertussis was surveyed bacteriologically and serologically for 2 months. Among the 9 immunized, 7 children acquired the laboratory-confirmed pertussis and 1 of the 7 developed the typical symptoms (whooping or paroxysmal coughing attack lasting for 14 days or more). Among the 10 unimmunized, 7 children acquired the laboratory-confirmed pertussis and 6 of the 7 developed the typical symptoms. There was no difference in the rate of secondary infection (7/9: 7/10), but there was a significant difference in the rate of development of the typical symptoms (1/7: 6/7 p<0.05). The point estimate of protective efficacy of the acellular DTP vaccine against typical pertussis was (6/10-1/9)/(6/10)×100=81%.
It was concluded from these findings that acellualr DTP vaccine could not prevent the infection of Bordetella pertussis, but could prevent the development of the typical symptoms.

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Antibody for HTLV-I in sera from 11, 224 residents in Miyazaki Prefecture, Japan, was determined by indirect immunofluorescent antibody method to compare age-and sex-specific antibody prevalence among three geographically divided areas of the prefecture. There was a significant difference in the positive rate of older age groups among three areas, 9.0% for the northern part, 14.5% for the southern part and 8.4% for Miyazaki City, in spite of little variation in younger age groups. A marked rise of positive rate in the southern part at the age of 40th was observed, which suggests that changes of some conditions for mother-to-child transmission happened in the time of their birth.
Six seroconversions were observed by the follow-up study for five years of the 971 residents. They were between 28 and 38 years of age, four men and two women. This may provide another reason for the increase in antibody positive rate by age in the adult. However, it could not be investigated if the seroconversion was caused by a horizontal transmission from their spouse. The possibility of the long latency of the virus in man as in the experimental animal may also have to be considered.

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The adherence of bacteria to mucosal surfaces is an important initial event in the pathogenesis of most bacterial infectious diseases. In order to clarify the mechanism of respiratory tract infections caused by Pseudomonas aeruginosa, we paid attention to pili (fimbriae), which is one of the adherence factors for the nonmucoid strains of P. aeruginosa. The adherence of P. aeruginosa was studied using two mutants: piliated and nonpiliated strains and 0.1 N hydrochloric acid-injured mouse tracheal epithelium as a respiratory tract model. The adherence ability was evaluated by means of direct count of adhered bacteria using a scanning electron microscope. The effect of antimicrobial agents was studied on the adherence and the production of pili.
Both mutants of P. aeruginosa adhered more significantly to the acid-injured tracheal epithelium than the normal one (p<0.01). The number of the piliated strain adhering to the acid-injured tracheal epithelium was significantly greater than that of the nonpiliated strain (p<0.01). The piliated bacteria treated with heat, formalin, antiserum against pili, N-acetylneuraminic acid and N-acetylglucosamine showed a significant decrease in number of adherence. The piliated bacteria were grown in a media containing 1/4 MICs of seven antimicrobial agents for four hours at 37°C, after that a significant reduction in the number of pili per bacterium was recognized with erythromycin, minocycline and clindamycin (p<0.01). The piliated bacteria treated with erythromycin showed a significatn decrease on adherence to the acid-injured tracheal epithelium in parallel with piliation. These results suggest that pili play an important role in adherence of P. aeruginosa (nonmucoid strain) and that N-acetylneuraminic acid and N-acetylglucosamine are important constituents of the receptor for pili. It is also infered that subminimal inhibitory concentrations (sub-MICs) of antimicrobial agents, such as erythromycin, suppress the formation and expression of the bacterial surface adhesin-pili and cause a significant reduction in adherence correlated with decreased production of pili of P. aeruginosa. This possible mechanism may partially explain that low concentrations of erythromycin control and prevent the respiratory tract infections due to P. aeruginosa.

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Strain ST67P of Staphylococcus hyicus was capsular type I (++)/II (+) of S. epidermidis as determined by the method of Ichiman. To mice immunized with heat-killed vaccine of strain ST67P, homologous strain and strain ATCC 31432 (capsular type I), SE-360 (capsular type II) and SE-10 (capsular type III) of S. epidermidis were injected intraperitoneally into mice, then, the viable cell number of the organisms in the peritoneal cavity were enumerated of 30 minutes and 20 hours after the injection.
Results showed that the viable cell number of the homologous strain and strain ATCC 31432 was remarkably decreased at 20 hours after the injection, however, the cells were increased with strain SE-360 and SE-10. Passive protective activity of rabbit anti-ATCC 31432 serum was absorbed either with homologous strain or strain ST67P in the mouse, however, protective activity of anti-SE-360 strain serum and anti-SE-10 strain serum was not absorbed with these organisms although the activity was absorbed with homologous organisms. With an ultrathin sectin preparation of strain ST67P conjugated with ferritin-labelled rabbit anti-homologous strain serum, numerous ferritin granules surrounding the outermost layer of large capsule were electronmicro-scopically demonstrated. In the same organisms treated with ferritin-labelled anti-ATCC31432 strain serum, the all walls were surrounded by a relatively thinner capsule and a number of ferritin granules were located in the outermost layer of the capsule. However, with the organisms treated with ferritin-labelled anti-SE-360 strain serum only a number of ferritin granules were shown on the surface of the cell walls, and neither capsule nor ferritin granules were exhibited in the organisms treated with ferritinlabelled anti-SE-10 strain serum.

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The genus Acinetobacter was recently re-classified by Bouvet and Grimont who described four new species, A. baumannii, A. haemolyticus, A. johnsonii and A. junii, and five unnamed genospecies, with a re-definition of A. calcoaceticus and A. lwoffii which appeared in the Approved Lists of Bacterial Names, 1980.
One hundred and twenty-eight clinical isolates previously identified as Acinetobacter were retrieved from storage and re-characterized by using a system based on the grouping reactions described by Bouvet and Grimont. Of these 86.7%, 2.3%, and 1.6% were identified as A. baumannii, A. junii and Acinetobacter genospecies 11, respectively, and the remaining 9.4% of the cultures were unidentified. None of the cultures identified as A. calcoaceticus and A. lwoffii was included in the 128 cultures.

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In order to detect Campylobacter pylori in the gastric mucosa, three different methods as 1) culture of the organisms, 2) immunostaining by monoclonal antibody against the cells, and 3) urease test were compared. In the disease group, positive % of each methods was 64, 75 and 74. However, positive % common to the three methods was only 48. The corresponding rate of culture and urease tests, and that of culture and staining methods was 81% and 60%, respectively. Therefore, it was concluded that urease test was a useful method, and that the three methods were necessary to confirm the existence of the organisms in the gastric mucosa. Total positive % of culture and staining methods in disease and control groups was 77 and 31, respectively, indicating that positive % of the disease group was much higher than that of the control group.
Anti C. pylori titer was compared between culture-positive and culture-negative patients by ELISA. The titer of the former was significantly higher than that of the latter.

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In the prior two reports, we demonstrated that G-CSF induced the polarization of neutrophils by itself, and also enhanced superoxide production from neutrophils stimulated by the chemotactic peptides.
In this study, we have examined the protective effect of G-CSF in vivo on Pseudomonas pneumonia and septicemia in mice.
Cyclophosphamide (CY) induced severe reduction of the number of peripheral leukocytes and weakned resistance for Psuedomonas aeruguinosa infection of mice. However, in mice recieving recombinant human G-CSF four daily subcutaneous injection, the number of leukocytes, particulary neutrophils, increased more rapidly than in controls recieving saline. Moreover G-CSF enhanced a protective effect to pulmonary and systemic pseudomonas infections.
When G-CSF was administered together with antibiotics, significant synergism in the protection against plumonary infection of Pseudomonas was observed.
Carrageenan treatment decreased the protective effect of G-C SF. These results suggested that the protective effect of G-CSF against P. aeruginosa infection depends not only on PMN but also another complexed host defence mechanism.

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A total of 391 strains of salmonella isolated from patients with sporadic cases of diarrhea during the period from April 1985 to June 1989 in Yamanashi Prefecture, were tested for their serovars, drug susceptibility and conjugative transmissible R plasmids.
The results can be summerized as follows:
1) The isolates were serologically classified into 35 different serovars. The predominant serovars were S. Typhimurium (24.8%), S. Litchfield (9.2%), S. Oranienburg (9.0%), S. Enteritidis (7.9%) and S. Hadar (6.1%).
2) Serovars of S. Hadar, S.Brandenburg, S. Chester, S. Chailey, S. Oslo and S. Inchpark were isolated from human sources for the first time in Yamanashi Prefecture.
3) Monthly frequency of isolates were August (17.3 strains), September (11.3 strains) and May (10.6 strains).
4) The predominant ages of isolates were 2 years of age (17.1%), 1 years of age (15.1%), 3 years of age (11.2%), under 1 years of age (10.7%) and 4 years of age (9.8%).
5) The rate of isolates from male were higher than female. (Male: 57.5%, Female: 42.5%).
6) The frequency of resistant isolates was 45.8% in the period. The most predominant resistance pattern was SA·SM·TC·CP·KM·ABPC resistance (11.2%).
Conjugative transmissible R plasmids appeared in 41.3% of the resistant strains.
7) The number of resistant strains of S. Typhimurium was 57 out of 97 strains (58.8%).

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Edwardsiella tarda (E. tarda) is gram negative enterobactereaceae which has been found generally in animal hosts and occasionally in human feces. We have reported a case of sepsis caused by E. tarda, complicated panophthaimitis and pyogenic spondylitis. A-39-year old patient suffered from fever, polyarthralgia and lumbago. We performed blood culture, from which E. tarda was isolated. Spinal CT scan showed destruction and osteogenesis of the fourth and fifth lumbar vertebral body and cranial CT scan showed destruction of the right lens. So we diagnosed sepsis with pyogenic spondylitis and panophthalmitis. We suspected that chronic ethanol administration reduced the resistance to infection of E. tarda which caused sepsis.

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A 46-year-old male was admitted to our hospital because of relapse of acute myeloblastic leukemia (M₂). Remission was successfully reinduced after reinduction chemotherapy consisting of daunorubicin, cytosine arabinoside, etoposide and vincristine, but was complicated by neutropenia. After the therapy, the patient had persistent fever of abot 38°C despite broad-spectrum antibiotics therapy and the patient developed pain in the right quadrant of the abdomen. The white blood cell count rose to 23000/mm3. Liver function tests showed abnormal findings mainly consisting of an elevated serum alkaline phosphatase level. Ultrasonograpy showed multiple hypoechoic lesions in the liver and CT scans also revealed multiple low density areas. Therefore he was suspected of having a complication of liver abscesses. Amphotericin B was administered 75 mg/day intravenously every other day. A percutaneous liver biopsy was performed, but was not diagnostic. Blood cultures were negative for pathogens. Amphotericin B was administered up to a cumulative dosage of 2.3 g, but the patient remained fevrile. Then he had an exploratory laparotomy and an open liver biopsy. The liver biopsy samples showed fungal elements proved by PAS staining. A catheter was inserted into the portal vein. Administration of Amphotericin B was started 20 mg daily through the cathter. The temperature fell to normal after institution of this therapy. The abnormal findings in CT scans almost disappeared and the inflammatory findings became negative after he had received intraportal administration of Amphotericin B over three months.
Through the analysis of this case study, we confirmed that the intraportal administration of Amphotericin B was effective to the intractable liver abscesses due to fungi.

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A 43-year-old woman visited a clinic for an attack of bronchial asthma which she had been suffering since her childhood. She was treated with prednisolone which was used for the first time. Two weeks later, she had a fever and her chest X-ray showed diffuse reticulonodular shadows on both middle to lower lung fields.
In spite of the use of antibacterial drugs, her symptoms such as cough, dyspnea, malaise and fever increased. It was revealed that she had Stronglyoides sterocoralis in the stool. She was referred to our department for treatment and further examination.
Transbronchial lung biopsy (TBLB) was performed, and cyst of Pneumocystis carinii were histologically detected in the lung specimen. Anti-human T-lymphotropic virus type 1 (HTLV-1) antibody in the serum was 1: 4, 096C. Typical adult T-cell leukemia (ATL) cells were also observed in the periperal blood smear at the rate of 10-15% of leukocytes. The parasite was observed in the sputum too.
We diagnosed her as having Pneumocystis carinii pneumonia with hyperinfection of Strongyloides stercoralis complicated with smoldering ATL, and the pneumonia might have been induced by steroid therapy (total dosis of 500 mg, for 25 days).
After sulfamethoxazole-trimethoprim (ST compound) was used for the Pneumocystis carinii pneumonia, her symptoms markedly subsided, and the chest X-ray findings turned to normal by 45 days after the treatment. Thiabendazole was initially administered for the Strongyloidiasis and the parasite temporarily disappered from both sputum and stool. Then pyruvinium pamoate and mebendazole were used, but the parasite could not be completely eradicated in the stool. We did not treat the smoldering ATL because there were no symptoms.
We have been looking after her as an outpatient now, and she has neither symptoms nor signs.

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A 34-year-old man, a heavy drinker, was admitted with a high fever and hematuria two months previously. Surgery was performed for acute sever pancreatitis and postoperatively antibiotics were administered with intravenous hyperalimentation. After discharge he was readmitted and infective endocarditis was strongly suspected because of high fever, hematuria, Osler's nodes, Janeway's lesions, splinter hemorrhages and mitral regurgitation. Penicillin G in combination with Gentamycine therapy was started on the first hospital day. On the second hospital day, blood culture reveaeld Candida tropicalis so Miconazole therapy was commenced. On the forth hospital day, he underwent surgery for replacement of a mitral prosthesis with a prosthetic valve because he had embolus in the radial artery.
Despite intensive antifungal therapy, he showed no imporvement in clinical symptoms. Then we changed the antifungal drug from Miconazole to Amphotericin B and 5-fluorocytosine. On the 109th hospital day, his clinical symptoms improved. Antifungal therapy was halted and at present 10 months later, he is healthy.

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