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We treated an extremely rare case of a mycotic aneurysm with infection of an artificial blood vessel by Saccharomyces cerevisiae, which was the first case in Japan. The patient was an 84-year-old woman. Five months before hospitalization, replacement of the ascending aorta was performed for a dissecting aneurysm of the ascending aorta. On regular follow-up examination, she had no symptoms, but accumulation of a liquid was detected around the artificial blood vessel on computed tomography (CT) imaging. She was immediately hospitalized. An emergency operation was performed because of the infected aneurysm, which accompanied infection of the artificial blood vessel. We could not detect any microorganisms in the blood or tissue culture, but we made a diagnosis of S. cerevisiae infection after performing broad-range polymerase chain reaction (PCR), followed by deoxyribonucleic acid (DNA) sequencing analysis. When an infected aneurysm is suspected after imaging analysis, such as CT, in a patient without fever or chest pain and with poor inflammatory reactions, an infected aneurysm caused by a fungus should be considered, even though blood or tissue culture results are negative. It is important to perform histopathological examination using Grocott silver stain and genetic testing (broad-range PCR and DNA sequencing analysis) of the tissue to identify the fungal infection. In the elderly, the number of cases of infection with S. cerevisiae may increase, and these cases may require more attention in the near future.

A 46-year-old man presented with a 10-day history of progressive weakness and numbness in both his legs. The spinal MRI and abdominal CT revealed discitis of L4/L5 and multiple epidural abscesses. The blood culture tested positive for methicillin sensitive Staphylococcus aureus (MSSA). The Gram stain of sample from abscess drainage showed Gram-positive cocci in clusters and small Gram-negative rods. The Gram-positive cocci in clusters were identified as MSSA using a general culture method and the small Gram-negative rods were identified as Aggregatibacter aphrophilus using a 16s ribosomal RNA sequencing method. The patient was treated four times with surgical abscess drainages and a long course of intravenous antibiotics therapy following which he recovered. No case of mixed infection by A. aphrophilus and S. aureus has been reported in MEDLINE; therefore, our case should be the first case report. Since we confirmed not only Gram-positive cocci in clusters but also Gram-negative rods in the abscess sample, we did not stop the identification procedure at the point when MSSA was identified and finally identified A. aphrophilus with 16s ribosomal RNA sequencing. Especially, in a mixed infection with organisms whose growth speed is different, an organism with slow growth might be missed if the Gram stain of sample were skipped. This case implies the significance of Gram staining as the identification procedure for organisms.

Aerococcus urinae is a endocarditis rare causative organism with low virulene. We report an A. urinae endocarditis case treated by aortic valve replacement. An 80-year-old woman hospitalized for urinary tract infection and hydronephrosis due to three-week renal calculi. Blood culture on admission isolated Streptococcus acidominimus. During the course, she was transferred to our care for surgical intervention after developing congestive heart failure due to severe aortic regurgitation. Echocardiographic findings indicated infective endocarditis. She underwent aortic valve replacement, and gram staining of the resected valve tissue showed gram-positive cocci, although valve culture was negative. PCR amplification and DNA sequencing using the valve material matched an A. urinae sequence. The woman recovered and was discharged six weeks after antibiotic treatment.

We report three cases of acute conjunctivitis due to different types of human adenovirus (HAdV) in medical workers. Case 1: A 37-year-old man had epidemic keratoconjunctivitis and urethritis caused by human adenovirus type 37 (HAdV-37). Case 2: A 27-year-old woman had acute conjunctivitis due to human adenovirus type 15 (HAdV-15), Case 3:A 32-year-old woman had acute follicular conjunctivitis leading to a serotype of human adenovirus-53 serotype (HAdV-53). Note that HAdV-37 infection may cause keratoconjunctrivitis and urethritis. HAdV-15, -37, and -53 are important causative agents of nosocomial outbreak, and the application of a rapid diagnostic kit or PCR to a rapid diagnosis and proper infection-control measures can significantly reduce infection spread.

Conventional polymerase chain reaction (PCR) used to identify mycobacterial species does not distinguish between Mycobacterium tuberculosis and M. bovis BCG, and several weeks or months may be needed to identify individual slow-growing Mycobacterial species. We report a 4-year-old girl who had subcutaneous abscess and sternal osteomyelitis after BCG vaccination at 4 month of age. We directly identified M. bovis BCG genome in the punctured abscess within a few days using PCR and PCR-restriction fragment length polymorphism. Such PCR is useful for rapidly diagnosing and managing of appropriate therapy in patients with infection due to M. bovis BCG.

MRSA infection or colonization developed in eleven patients with neoplastic disease including malignant lymphoma (5 cases), soft tissue sarcoma (2 cases), acute myeloblastic leukemia (one), myelodysplastic syndrome (one), multiple myeloma (one), and mesothelioma (one) at our ward from October to December 1999. The infections were pneumonia (six cases), enteritis (three), bacteremia (one), and wound infection (one). Ten of 11 cases received antimicrobial agent (s) during one month before isolation of MRSA, suggesting selection of MRSA. Five cases improved and survived, but six cases died of infection. At the isolation of MRSA, the neutrophil count (NC) of the alive cases was 1, 500/microliter or more but the NC of five cases who died was less than 1,000/microliter, especially less than 100/microliter in three cases who had just received a cancer chemotherapy. Pulsed-field gel electrophoresis, performed in 9 cases, showed an identical DNA-pattern of MRSA in 7 cases, indicating a nosocomial infection. Our method to prevent spread of MRSA targeting solely the patients with MRSA infection was obviously unsatisfactory. We should target also the cases of MRSA colonization and make an effort to wash hands more vigorously. Furthermore, radical reformation such as increasing single sick-rooms drastically and increasing the number of nursing staff is also required.

Twenty-three cases of systemic pneumococcal infection diagnosed from October 1988 to September 1998 were analyzed retrospectively in order to characterize the epidemiology of systemic pneumococcal infections. The clinical diagnosis of those cases were 8 pneumonia, 8 meningitis, 3 septicemia, 3 septic arthritis, and 1 peritonitis. The patients ranged in age from 6 months to 21 years old (mean +/- SD = 3 years, 6 months +/- 5 years, 2 months), and 61% of the patients were younger than 24 months. Resistance to penicillin G (PCG) was detected in 57% of all cases. Resistance to cefotaxime (CTX), imipenem (IPM), erythromycin (EM), and clindamycin (CLDM) was 33%, 9%, 70%, and 65%, respectively. Of the 13 isolates resistant to PCG, 2 were resistant to IPM, 11 to EM and 11 to CLDM. Serotyping was performed on 17 isolates. The identified serotypes were 19 (6 isolates), 6 (5 isolates), 23 (3 isolates), 14 (2 isolates), and 5 (1 isolate). Eleven isolates resistant to PCG were limited to serotypes 6, 19, or 23. One patient had a recurrent episode of bacteremic pneumonia 7 months after the first episode. Streptococcus pneumoniae isolates from both episodes were compared by serotyping and pulsed-field gel electrophoresis with restriction digestion, and were confirmed as the same strain.

Twenty-eight cases of bacterial meningitis during the recent ten years were analyzed retrospectively, and the following results were obtained. 1. Pathogens were as follows; H. influenzae 13 (46.4%), S. pneumoniae 8 (28.6%), S. agalactiae 4 (14.3%), E. coli 2 (7.1%), and L. monocytogenes 1 case (3.6%). 2. Twelve out of the thirteen H. influenzae cases were caused by serotype b (Hib), and 2 strains were beta-lactamase producer. Fifty percent of the S. pneumoniae cases were caused by penicillin-resistant strains. And all these resistant strains belonged to serotype 19 or 23. 3. Underlying diseases related to the onset of meningitis were found in 46% of the cases, and these consisted of CNS shunt operated 5, asplenia or polysplenia 2, Mondini's anomaly 1, sacral dermal sinus 1, and neonate 4 cases. 4. Prognosis of these cases were three deaths, four with neurologic sequelae, and twenty-one complete recoveries. 5. On admission, 85% (17/20) of the cases were diagnosed correctly by the rapid antigen detection. Sensitivity and specificity of the rapid antigen detection by using latex particle agglutination is 90% and 100% in the Hib cases, and 83% and 100% in the S. pneumoniae cases respectively. Moreover, the bacteriologically unknown 2 cases caused by parenteral partial treatment were also diagnosed by the detection of antigen in concentrated urine.

Twenty-eight cases of systemic infections due to Haemophilus influenzae diagnosed from October 1988 to December 1998 were analyzed retrospectively. The clinical manifestations were 13 meningitis (15 episodes), 9 septic arthritis, 4 acute epiglottitis, 1 septicemia and 1 lung abscess. In the 15 meningitis episodes, 13 had positive CSF culture results, and the other 2 episodes of pretreated with antibiotics were diagnosed by H. influenzae type b (Hib) antigen detection by using concentrated urine specimens. In the 9 septic arthritis cases, 6 had positive synovial fluid culture results. Of the 3 cases with negative results on Gram stain and on synovial fluid and blood cultures, etiological diagnosis was established by Hib antigen detection in synovial fluid. Results of Hib antigen detection were positive in all 8 cases (100%). In 6 of these 8 cases, antimicrobial therapy was started by the results of antigen detection. In the 4 acute epiglottitis, 2 had positive blood culture results, and the other 1 case was diagnosed by Hib antigen detection by using concentrated urine specimen. In 3 of these 4 cases, H. influenzae strains isolated from nasopharyngeal swab or aspirated sputum were serotyped as type b. In this study, rapid antigen detection has several advantages in the rapid laboratory diagnosis of systemic infections due to Haemophilus influenzae. 1. The detection of Hib antigen is the only way to diagnose bacterial etiology of infection in patients who had received partially treatment with antimicrobials. Urine is as an appropriate specimen for antigen testing as CSF in patients with suspected Hib meningitis. Moreover, to detect Hib antigen in synovial fluid is clinically useful in septic arthritis. 2. Both the antigen detection and Gram stain made the rapid presumptive identifications and effected therapeutic decision making. 3. Antigen detection methods have also been used in serotyping of clinical isolates. We conclude that rapid antigen detection is a very useful tool for the rapid etiological diagnosis and guideline for the choice of antimicrobials in systemic infections due to Hib. It is necessary to diagnose bacterial etiology as a routine procedure using not only Gram stain and culture but also rapid antigen detection technique in patients with suspected Hib systemic infection.