In July 2002, a large outbreak of legionellosis occurred in a bathhouse with spa facilities in Miyazaki Prefecture. Two hundred-ninety-five patients (including suspected cases) that had pneumonia and/or symptoms of fever, cough and so forth were reported; 37% of them were hospitalized and seven people died. In environmental investigations, Legionella pneumophila serogroups (SGs) land 8, L. dumoffii, L. londiniensis, some other Legionella species and many kinds of amoeba were isolated from 55 samples of bathtub water, tank water, filters and so forth in the spa facilities. The dominant isolates from the bathtab waters belonged to L. londiniensis, L. dumoffil and L pneumophila SGI, and their maximum concentrations were 1.5×10⁶, 5.2×10⁵ and 1.6×10⁵cfu/100mL, respectively.
L. pneumophila SG1 strains isolated from bathtub water, tank water, filters and sputa of patients showed a indistinguishable DNA fingerprint pattern by pulsed-field gel electrophoresis (PFGE), confirming that the source of infection was the spa water. Our study indicate that spas may be a significant health hazard if hygienic management fails.

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In order to know the rubella immune status of Japanese women aged 20 to 39 years old, we analyzed the hemagglutination-inhibiting antibody titration data on 264, 371 sera which were sent to a commercial diagnostic laboratory from gynecology clinics all over Japan during 1999 through 2003. We found that antibody-positive rates remained at about 95% during the period, but, from 2000. geometric mean antibody titers of the positive sera gradually decreased each year. Annual analysis of the data will be useful for monitoring the trend of rubella immunity among Japanese women of childbearing age.

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The epidemiologic features of respiratory syncytial virus (RSV) infection were investigated by detecting the virus in throat swab specimens from patients with acute respiratory symptoms attending the sentinel surveillance clinics in Yokohama City in 5 seasons from July 1998 to June 2003.
Throughout the 5 seasons, RSV was found from 181 in 2, 683 specimens tested (6.7%) by virus isolation in cell culture or genome detection using nested RT-PCR, and this detection rate followed that of influenza virus (infl.v.) (441/2683; 16.4%), while the proportion of RSV isolates in a season fluctuated from 12 to 22% of all causative viruses identified.
Analysis of monthly detected number of strains revealed that the peak of RSV isolation was present in December which preceded that of infl.v. by 2 months. Moreover, RSV strains were isolated sporadically during late spring to early autumn (from May to September) when infl.v. was scarcely detected.
Among 181 RSV strains, 172 could be subgrouped; 104 were identified as subgroup A, while 68 were B. Subgroup A were detected more frequently throughout the 5 seasons (57%), though the proportion varied seasonally and subgroup B exceeded both in 2000/2001 and 2002/2003 seasons (61% and 70%. respectively).
Clinical characteristics of RSV-infected patients were compared with those infected with infl.v. Age distribution of cases revealed that RSV detected predominantly (79%) from lower age groups (less than 5 years) compared to infl. v (41%). As for the proportion of cases showing clinical symptoms of lower respiratory inflammation predominated in RSV-infected irrespective of age groups.

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The antimycobacterial susceptibility test was performed and minimal inhibitory concentration (MIC) to drugs was determined in 98 strains of Mycobacteium tuberculosis (MTB) isolated in Tokyo from 2000 to 2003, to find which were resistant to any of the four main anti-MTB drugs, isoniazid (INH), rifampicin (RFP), streptomycin (SM), and ethambutol (EMB). 27strains of them were resistant only to SM, and 16 strains were resistant only to INH. 51 strains of them were resistant to not only INH but also other drugs. 38 strains were resistant to both INH and RFP. 19 strains were resistant to all four drugs, including 7 strains resistant to new quinolon anti-biotics also.
Nucleotide or amino-acid mutations in drug resistant MTB genome were determined by DNA sequencing method. Mutation of codon 516, 526, or 531 of rpoB gene was detected in 98% of MTBs resistant to RFP. Deletion or insertion of katG gene or nucleotide mutation at regulatory region of ahpC gene was detected in MTBs highly resistant to INH. Amino acid mutation of katG gene, especially at codon 315, was detected in MTBs resistant to INH intermediate. Nucleotide mutations at regulatory region of inhA gene were detected in MTBs resistant to INH at low level. Amino acid mutation at codon 43 or 88 of rpsL gene was detected in MTBs highly resistant to SM, and nucleotide mutation at 512, 513, or 516 of rrs gene was detected in MTBs resistant to SM at low level. Amino acid mutation at codon 306 of embB gene was detected in 87% of MTBs resistant to EMB.

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We report an unusual case of Acinetobacter baumannii (A. baumannii) bacteremia in a man without significant comorbidities. A 50-year-old man who noticed a sudden onset of high fever was admitted to Kobe Nishi City Hospital. After the admission, his condition deteriorated rapidly with development of shock, anuria and agitation. Antibiotic therapy with meropenem and amikacin was begun for suspected septic shock along with the mechanical ventilation and continuous hemodialysis. Venous blood cultures yielded A. baumannii. No definite source of bacteremia was detected. Intensive medical management was effective, and he was discharged on the 27^th day. While the most common source of infection that leads to A. baumannii bacteremia is in the respiratory tract, community-acquired bacteremia with unknown foci is considered rare.

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We report four cases of tuberuculosis with the lymph nodes swelling in the porta hepatis.
Case 1 is 52 years-old man, who was admitted to our hospital because of anorexia. The chest Xray film showed abnormal shadow and he was diagnosed as tuberculosis by sputum examination. At the time of hospitalization, patient's conjunctiva is icteric on physical examination. The serum T-Bil was 3. 21mg/dL and D-Bil was 2. 54mg/dL. The enhanced CT showed compression of the extrahepatic common bile duct which was caused by enlarged lymph nodes secondary to tuberculous adenitis.
Case 2 is 25 years-old man, who was admitted to our hospital because of low grade fever and lower abdominal pain. The chest X-ray film showed abnormal shadow and he was diagnosed as tuberculosis by sputum examination. An enhanced CT showed the swelling of the lymph nodes in the porta hepatis.
Case 3 is 21 years-old woman, who visited the outpatient clinic bacause of neck lymph node swelling. And she was diagnosed as tuberculous adenitis of the cervical lymph-nodes by the neck lymph node biopsy. The patient complained of upper abdominal pain during the clinical course. The enhanced CT showed the swelling of the lymph nodes in the porta hepatis.
A Case 4 is 31 years-old man, who visited to outpatient clinic bacause of fever. The chest X-ray film showed mediastinal lymphadenopathy, and he was diagnosed as tuberculosis by the thoracoscopic biopsy. The enhanced abdominal CT showed lymph nodes swelling in the porta hepatis.
All of lymph nodes swelling found in our four cases markedly reduced in size on abdominal enhanced CT or ultrasonography after the initiation of anti-tuberculous standard chemotherapy. Symptom of all cases got better as well. In these clinical circumstances, it was clinically important to rule out malignant lymphoma and lymphadenopathy caused by cancer. The enhanced abdominal CT were useful for diagnosis and follow-up as tuberculous adenitis.

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