Successful treatment of invasive zygomycosis based on a prompt diagnosis using molecular methods in a patient with acute myelogenous leukemia

Zygomycosis is a lethal and invasive mold infection that is often associated with hematological malignancies. The keys for successful treatment include making a rapid diagnosis and appropriately administering antifungal agents. We herein report the early diagnosis of a case of zygomycosis in a patient with acute myeloid leukemia using a deoxyribonucleic acid sequence analysis. We successfully performed allogeneic hematopoietic stem cell transplantation with the use of high-dose liposomal amphotericin B and granulocyte transfusion.

Quantitative Microarray-Based DNA-DNA Hybridization Assay for Measuring Genetic Distances among Bacterial Species and Its Application to the Identification of FamilyEnterobacteriaceae

Quantitative DNA-DNA hybridization to measure the genetic distances among bacterial species is indispensable for taxonomical determination. In the current studies, we developed a method to determine bacterial DNA relatedness on a glass microarray. Reference DNAs representing a total 93 species of Enterobacteriaceae were arrayed on a glass microplate, and signal intensities were measured after 2 hr of hybridization with Cy3-labeled bacterial DNAs. All immobilized DNAs from members of the family Enterobacteriaceae were identified by this method except for DNAs from Yersinia pseudotuberculosis and Y. pestis. These results suggest that quantitative microarray hybridization could be an alternative to conventional DNA-DNA hybridization for measuring chromosome relatedness among bacterial species.

Virulence-Defective Strains ofSalmonella entericaSerovar Typhi as Candidates for Education at Level 2 Facilities

The use of biosafety level 3 pathogens is an essential element of education and training at medical schools. We previously reported on invasion-defective strains of Salmonella enterica serovar Typhi, GTC 3P408 (DeltainvA, DeltasipB) and GTC 3P409 (DeltainvA, DeltasipB, and DeltaviaB), as candidates for use in educational programs. Vi negative strains of S. enterica serovar Typhi became extremely sensitive to complement attack but showed increased invasiveness. Therefore, this study was conducted to construct two virulencedefective strains, GTC 3P460 (DeltainvA, DeltasipB, and DeltarpoS) and GTC 3P461 (DeltainvA, DeltasipB, DeltaviaB, and DeltarpoS), of S. enterica serovar Typhi by deleting rpoS from the GTC 3P409 and GTC 3P408 strains. Stress tests demonstrated that GTC 3P460 and GTC 3P461 are sensitive to conditions of starvation, acid stress and oxidative stress. These results suggest that these virulence-defective strains have difficulty surviving in the gastric environment and in macrophages, characteristics that make them ideal candidates for education at level 2 facilities. Colony morphology and conventional biochemical features of these strains are identical to the parent strain S. enterica serovar Typhi GIFU 10007.

Moraxella lacunata infection associated with septicemia, endocarditis, and bilateral septic arthritis in a patient undergoing hemodialysis: a case report and review of the literature

We report the first case of both endocarditis and bilateral septic arthritis in a patient caused by Moraxella lacunata and successful management of the infection with antimicrobial therapy. The route of entry leading to bacteremia may have been the oral cavity given the poor oral hygiene of the patient as evidenced by bleeding gums. We hypothesize that the bacteremia led to septic arthritis and mitral valve infective endocarditis. In this case report, we also review the literature on M. lacunata infections and conclude that this organism should be considered in bilateral septic arthritis in a patient with underlying heart abnormalities and/or with renal failure.

Pyogenic discitis due to Abiotrophia adiacens

INTRODUCTION

Abiotrophia species have been referred to as nutritionally variant streptococci because of their fastidious nutritional requirements for growth. Abiotrophia species are difficult to identify with conventional solid culture.

PRESENTATION OF CASE

A 48-year-old woman was admitted to our hospital with severe low back pain and body temperature of 38.2 °C. Magnetic resonance imaging revealed edema and contrast enhancement of the L4 and L5 vertebral bodies with high signal intensity in the L3-4 and L4-5 intervertebral discs on the T2-weighted images. The patient underwent needle biopsy of the L3-4 disk. Cultures of disk biopsy samples and blood yielded gram positive cocci in short chains with scanty growth on chocolate agar. Further subculture with supplemented medium and subsequent 16S ribosomal RNA gene sequencing identified the pathogen as Abiotrhophia adiacens. The patient was treated with intravenous ampicillin. At 6-month follow-up, the patient was free of symptoms.

DISCUSSION

Causative microorganisms remain unidentified in 25–40% of spinal infection cases. Abiotrophia species grow poorly on conventional solid media, and require pyridoxal or thiol group supplementation. Use of Brucella HK agar or GAM agar plate is helpful for detection of Abiotrophia species. We first confirmed the diagnosis by direct identification of Abiotrophia adiacens from infected disk. Abiotrophia species are one of the major pathogens of infective endocarditis accounting for 5% of cases. Considering their fastidious nature, it is likely that most cases of Abiotrophia discitis are falsely classified as culture-negative discitis; therefore, their role in pyogenic discitis may be underestimated.

CONCLUSION

Subculture using nutritionally supplemented media is crucial for their identification.

[A case of culture-negative brain abscess caused by Streptococcus intermedius infection diagnosed by broad-range PCR of 16S ribosomal RNA]

A 50-year-old man presented with altered mental status during hospitalization for pneumonia. MRI showed multifocal ring-enhanced lesions, which consisted of multiple cerebral abscesses. We started empirical antibiotic therapy, but the following morning, his condition rapidly deteriorated and a CT scan revealed acute hydrocephalus, which required ventricular drainage. Gram staining of cerebro-spinal fluid from the ventricular drainage showed gram-positive cocci in chains, but culture results were negative. 16S ribosomal RNA sequencing with broad-range PCR of the cerebro-spinal fluid identified Streptococcus intermedius. On the basis of this identification, the antibiotic regimen was changed to ampicillin monotherapy. After 1 year of antibiotic therapy, all the abscesses had disappeared and the patient was discharged without any sequelae. Bacterial 16S rRNA gene analysis with broad-range PCR is a very useful method for facilitating the etiological diagnosis and selection of appropriate treatment for culture-negative infections.

Rare case of fungal keratitis caused by Corynespora cassiicola

We describe a 76-year-old male farmer with no diabetes mellitus and no history of ocular trauma from soil or plants who developed a corneal infection from a plant pathogen. The organism was identified as Corynespora cassiicola based on both the morphological characteristics and the sequence of the internal transcribed spacer region of the ribosomal RNA gene. The patient was treated successfully with a combination of topical and systemic voriconazole. This is the first reported case of keratomycosis caused by C. cassiicola.

Burkholderia contaminans: unusual cause of biliary sepsis

We report a case of biliary tract infection caused by a strain of Burkholderia contaminans, a member of the Burkholderia cepacia complex. The patient developed sepsis after endoscopic retrograde cholangiopancreatography (ERCP). Gram-negative bacilli were isolated from blood and bile cultures. Automated bacterial identification systems identified the organism as Burkholderia cepacia, whereas DNA sequence analysis revealed that the recA gene isolate was identical to that of B. contaminans. The patient responded to therapy with the antibiotics trimethoprim/sulfamethoxazole and biliary tract decompression. This case suggests that B. contaminans can be a causative agent of healthcare-associated biliary tract infections such as ERCP-related cholangitis.

Whipple disease diagnosed with PCR using formalin-fixed paraffin-embedded specimens of the intestinal mucosa

We herein present the case of a 54-year-old Japanese woman with Whipple disease diagnosed with polymerase chain reaction (PCR) using formalin-fixed paraffin-embedded (FFPE) specimens. The patient complained of weight loss, diarrhea and arthralgia. An endoscopic examination revealed swollen villi in the duodenum and ileum. Pathology demonstrated the presence of numerous macrophages filled with diastase-resistant PAS-positive particles. PCR using FFPE specimens amplified a fragment of 16S rDNA from Tropheryma whipplei. After the administration of ceftriaxone followed by trimethoprim/sulfamethoxazole, no signs of recurrence were observed for two years. The use of FFPE specimens for PCR should be considered for the prompt diagnosis and prevention of disease progression.

Bacillus cereus necrotizing pneumonia in a patient with nephrotic syndrome

Bacillus cereus (B. cereus) is a Gram-positive rod that is widely distributed in the environment and can be a cause of food poisoning. We herein present a case of B. cereus necrotizing pneumonia in a patient with nephrotic syndrome under corticosteroid treatment after developing transient gastroenteritis symptoms. B. cereus was isolated from bronchial lavage fluid and transbronchial biopsy specimens. A multiplex polymerase chain reaction analysis of the toxin genes revealed a strain possessing enterotoxicity. The patient recovered after one week of intravenous meropenem followed by a combination of oral moxifloxacin and clindamycin. B. cereus is a pathogen that causes necrotizing pneumonia in immunocompromised hosts.

Campylobacter showae bacteremia with cholangitis

We report a case of Campylobacter showae bacteremia associated with cholangitis. A 71-year-old man with advanced bile duct cancer was admitted to our hospital because of cholangitis with shock, hypoglycemia, and impaired renal function. After replacement of the biliary drainage tube, pus was drained from the tube. Specimens for blood and bile cultures were obtained, and fluid resuscitation and antimicrobial treatment were then begun. Although anaerobic blood culture yielded small curved gram-negative rods, the isolate could not be identified by conventional identification methods. The isolate was identified as C. showae by 16S rRNA gene sequencing analysis. We consider here the pathogenicity of C. showae and the association of C. showae with cholangitis.

Moraxella osloensis: an unusual cause of central venous catheter infection in a cancer patient

Moraxella osloensis is a rare causative organism of infections in humans, with most cases reported in cancer patients. We report the case of a 67-year-old Japanese man with advanced cancer of the pancreatic head and multiple liver metastases who developed fever with chills. Blood culture was found to be positive for Gram-negative bacilli that were aerobic, oxidase-positive, and catalase-positive. M. osloensis was identified by 16 rRNA gene sequencing. Prompt control of the infection was achieved by treatment with cefepime for 14 days, without the need for removal of the central venous catheter.

Comparative analysis of MRSA strains isolated from cases of mupirocin ointment treatment in which eradication was successful and in which eradication failed

Nasal decolonization in methicillin-resistant Staphylococcus aureus (MRSA) carriers using mupirocin (MUP) is a strategy that complements barrier precautions and contact isolation. However, eradication failure cases have been observed despite isolates being susceptible to MUP. This would suggest that the minimum inhibitory concentration (MIC) alone is not the only determinant of successful eradication. In this study, we undertook a comparative analysis of MRSA isolates from cases of successful and unsuccessful MUP-eradication treatment. The analyses we carried out were: determination of mupirocin MICs, sequencing of the isoleucyl-tRNA synthetase (ileS) gene, staphylococcal cassette chromosome mec typing, and the assessment of slime production. MICs for all 14 of the successful nasal decolonization cases showed susceptibility to MUP, whereas 21 (87.5 %) of the 24 unsuccessful cases were MUP-susceptible, with low-level resistance seen in 3 (12.5 %) strains. In the analysis of mutations in the ileS gene, one strain with an MIC of 4 μg/ml exhibited a G1778A point mutation that has not been previously reported. In the 14 successful nasal decolonization cases, only 1 strain (7.1 %) was an MRSA slime-producer, compared with 19 (79.7 %) of the 24 MRSA strains that could not be eradicated after MUP treatment (p < 0.05). For the eradication of MRSA by MUP, it is possible that slime may affect drug penetration. In conclusion, slime production was the only significant difference between isolates recovered from successful and unsuccessful eradication cases.

Bacterial pericarditis caused by Lactobacillus iners in an infant

We report the case of a 6-month-old male infant with bacterial pericarditis due to Lactobacillus iners. Although the culture of pericardial fluid was negative, L. iners was identified by 16S rRNA gene amplification by polymerase chain reaction and a subsequent sequence analysis. This weakly pathogenic bacterium could develop a severe infection in infants.

[Clinical manifestations, treatment and outcome of ocular infections caused by Paecilomyces species]

PURPOSE

To report the predisposing factors, patient background, treatment and outcomes of ocular infections caused by Paecilomyces spp. in Japan.

METHODS

We reviewed the medical records and the published literature in Japan on ocular infections caused by microbiologically-proven Paecilomyces spp. Nineteen eyes of 18 patients; 4 eyes of 4 of our patients and 15 eyes of 14 published Japanese patients were studied.

RESULTS

Ten men and 8 women (9 OD, 8 OS, 1 OU) were diagnosed with ocular infections caused by Paecilomyces spp. The mean age was 69 years (range 33 to 90 years). The initial diagnosis of ocular infection caused by Paecilomyces spp. was keratitis in 14 eyes and endophthalmitis in 5 eyes. The final diagnosis was keratitis in 2 eyes, keratitis with involvement of the anterior segment of the eye, i.e., hypopyon or corneal rupture, in 12 eyes, and endophthalmitis in 5 eyes. The predisposing factors had a history of ocular surgery, corneal trauma and soft contact lens use. Other factors were diabetes and old age. The infections developed more often in the fall and winter. The identified Paecilomyces spp. had a high sensitivity to micafungin and voriconazole, but low sensitivity to amphotericin B, flucytosine and fluconazole. The prognosis of Paecilomyces spp. ocular infections was very poor, viz., final vision was counting fingers or worse in 60%, ocular perforation in 42%, and eye enucleation in 11%. The percentage of eyes with a final visual acuity worse than counting fingers was 0% in those with keratitis, 50% in those with involvement of the anterior segment, and 100% in those with endophtalmitis (p = 0.0446). Among the antifungal agents, the percentage of cases with final vision of counting fingers or worse was 90% with fluconazole, 80% with itraconazole, 100% with miconazole, and 71% with voriconazole.

CONCLUSION

The results show that if the Paecilomyces spp. infection spreads intraocularly, it is difficult to mitigate the clinical damage even with antifungal agents with high sensitivity.

Identification and sensitivity of two rare fungal species isolated from two patients with Fusarium keratomycosis

We report two cases of Fusarium keratomycosis in which molecular analysis was used to identify two rare causative Fusarium species. A 65-year-old woman was diagnosed with Fusarium keratomycosis caused by F. equiseti, confirmed by sequencing the internal transcribed spacer (ITS) region and morphological characteristics. She was initially treated with topical corticosteroid but the keratitis did not improve. Even after aggressive antifungal treatment, there was a severe reduction of vision. In the end, the eye perforated. Our second case was a 75-year-old man who had diabetes mellitus. He developed keratitis after his cornea was injured by corn stalks. The ITS region identified the causative organism as F. verticillioides. Unlike the first case, he had good visual recovery after early antifungal therapy. Our findings demonstrate that both ITS and morphological characteristics can be used to identify the exact Fusarium species causing Fusarium keratomycosis. This allowed us to determine the sensitivity of these species to antifungal drugs that can be used to treat patients with these species of Fusarium.

Necrotizing pneumonia in the community

A 62-year-old man presented with general fatigue. He was diagnosed with septic shock and severe pneumonia. The sputum at admission yielded methicillin-sensitive Staphylococcus aureus (MSSA) strain and methicillin-resistant S. aureus (MRSA) strain. Despite antibiotic treatment, he did not improve. A chest computed tomography (CT) revealed multilobar cavity lesions. Only MRSA strain was confirmed at that time. We diagnosed him with necrotizing pneumonia. Despite treatment with vancomycin, his pneumonia worsened and he died. At autopsy, many gram-positive cocci were observed in the lungs. The clinical presentation of our patient was different from typical CA-MRSA-mediated necrotizing pneumonia.

Neonatal meningitis caused by Streptococcus gallolyticus subsp. pasteurianus

We encountered a case of neonatal meningitis caused by Streptococcus gallolyticus subsp. pasteurianus. The patient was an 8-day-old boy. Gram staining of the cerebrospinal fluid (CSF) revealed gram-positive cocci in pairs or in short chains. In culture, γ-streptococcus-like colonies grew. The result of 16S rRNA sequence analysis identified S. gallolyticus subsp. pasteurianus. From these results, bacterial meningitis was diagnosed and, as a result of antimicrobial susceptibility testing, single-dose ampicillin therapy was given. Because inflammatory deterioration and spread was suspected from the CSF test results, this therapy was added by panipenem/betamipron. In response to his recovery, antibiotic treatment was stopped and the boy was discharged. This bacterium was classified as S. gallolyticus subsp. pasteurianus in the latest report in 2003. Since this change, there have only been a few cases of neonatal meningitis caused by this bacterium. Here we report this rare case.

[A case of pulmonary nocardiosis due to Nocardia cyriacigeorgica with prompt diagnosis by gram stain]

An 82-year-old woman with a past history of a colectomy for colon cancer was admitted to our hospital because of fever and cough. Her chest radiologic images on admission showed bilateral pulmonary infiltration, which suggested community-acquired pneumonia. However, the results of gram and acid-fast staining demonstrated branching acid-bacilli, which suggested pulmonary nocardiosis. We administered sulfamethoxazole-trimethoprim, and her condition and radiology findings promptly improved. Nocardia cyriacigeorgica was identified from her sputum. One of the nocardial isolates, formerly identified as Nocardia asteroides, has recently been reclassified as Nocardia cyriacigeorgica by the 16S rRNA gene amplification method. Pulmonary nocardiosis may be misidentified as "aspiration pneumonia", especially in elderly people. It is important for patients with community-acquired pneumonia to be evaluated with sputum gram staining for accurate diagnosis.

Intraocular penetration of micafungin in patient with Candida albicans endophthalmitis

PURPOSE

To investigate the penetration of micafungin, a new class of echinocandin antifungal agent, into the aqueous humor and vitreous after an intravenous administration.

METHODS

Endogenous endophthalmitis caused by Candida albicans developed bilaterally in a 67-year-old man. Three hours before vitrectomy, the patient received an intravenous injection of 300 mg micafungin. Samples of aqueous and vitreous were collected during the vitrectomy approximately 60 min after the intravenous injection. The concentration of micafungin in both bodies was determined by high-performance liquid chromatography.

RESULTS

The concentration of micafungin was 25.36 μg/mL in the serum, 0.026 μg/mL in the aqueous, and 0.043 μg/mL in the vitreous. The micafungin minimum inhibitory concentration (MIC) against the C. albicans strain isolated from our patient was 0.03 μg/mL. Thus, the micafungin reached the MIC in the vitreous.

CONCLUSION

We suggest that intravenous micafungin should be considered in mild cases of endogenous fungal endophthalmitis, or be given in combination with other intravitreal antifungal agents with vitrectomy in more severe cases.

Atypical osteomyelitis of the skull base and craniovertebral junction caused by Actinomyces infection--case report

A 44-year-old man presented with a very rare case of skull base osteomyelitis manifesting as persistent diplopia. He initially had the symptom with fever after dental extraction. Biopsy from the cervix and upper pharynx performed in a previous hospital had showed negative findings by histological and bacterial examinations. Magnetic resonance (MR) imaging disclosed enhanced lesions in the right cavernous sinus, clivus, and right cervical regions. Computed tomography revealed osteolysis, and fluorodeoxyglucose positron emission tomography (FDG-PET) showed areas of increased uptake. Bacteriological examination of the isolated clival lesion disclosed Actinomyces israelii, and he was treated with intravenous penicillin, 18 million units a day for 6 weeks. MR imaging revealed reduction of intensity in the enhanced areas, and FDG-PET showed disappearance of the increased uptake. After 6 months of oral antibiotics administration, MR imaging disclosed disappearance of the enhanced lesions, and the patient had no sign of neurological deficits. Skull base osteomyelitis resembles neoplasm or inflammatory disease of this region in neurological and radiographic findings. The biopsy specimen should be ideally obtained from an isolated region, and prepared to identify a wide range of organisms and to differentiate other diseases. The serum level of C-reactive protein and FDG-PET are useful to follow up the efficacy of antibiotic therapy.

Mycobacterium shinjukuense sp. nov., a slowly growing, non-chromogenic species isolated from human clinical specimens

Seven isolates of a slowly growing, non-chromogenic Mycobacterium species were obtained from sputum and bronchial lavage fluid samples from elderly patients in different regions of Japan. These isolates were distinguished from related non-tuberculous species by colony morphology, positive results for Tween hydrolysis, catalase at 68 °C, nitrate reductase and pyrazinamidase and negative results for semi-quantitative catalase, urease and arylsulfatase. The mycolic acid pattern obtained by HPLC revealed a single cluster of late-eluting mycolic acids similar to but different from those of Mycobacterium malmoense ATCC 29571(T). The 16S rRNA gene, 16S-23S internal transcribed spacer (ITS), rpoB and hsp65 sequences were unique in comparison with those of other mycobacteria. Comparison of 16S rRNA gene sequences showed that the isolates were most closely related to Mycobacterium tuberculosis H37Rv(T) (21 base differences in 1508 bp; 98.6 % 16S rRNA gene sequence similarity). A representative strain, GTC 2738(T), showed 91.9 % rpoB sequence similarity with Mycobacterium marinum strain M, 95 % hsp65 sequence similarity with Mycobacterium kansasii CIP 104589(T) and 81.1 % 16S-23S ITS sequence similarity with Mycobacterium gordonae ATCC 14470(T). Phylogenetic analysis of concatenated sequences of the 16S rRNA, rpoB and hsp65 genes showed that strain GTC 2738(T) was located on a distinct clade adjacent to M. tuberculosis, M. ulcerans and M. marinum, with bootstrap values of 81 %. DNA-DNA hybridization demonstrated less than 70 % reassociation with type strains of genetically related species and supported the novel species status of the isolates. On the basis of this evidence, a novel species with the name Mycobacterium shinjukuense sp. nov. is proposed. The type strain, isolated from a sputum sample, is strain GTC 2738(T)( = JCM 14233(T) = CCUG 53584(T)).

Case of endogenous endophthalmitis caused by Streptococcus equisimilis

We report a rare case of endogenous endophthalmitis caused by Streptococcus equisimilis. A 74-year-old woman with endocarditis developed endogenous endophthalmitis. The patient underwent emergency mitral valvuloplasty, and intravitreal and subconjunctival injections of vancomycin and meropenem. After the surgery, she was treated with topical antibiotics, ointment, intravenous gentamicin and intravenous penicillin G potassium. The causative organism was identified as S. equisimilis. S. equisimilis should be considered as a pathogen that can cause severe endogenous endophthalmitis.

Case of endophthalmitis following intravitreal injections of bevacizumab

Purpose:

We report a case of infectious endophthalmitis that developed after the third intravitreal injection of bevacizumab. The endophthalmitis was caused by Staphylococcus epidermidis.

Methods:

Observational case series.

Results:

This was a case of a 77-year-old man who had received three intravitreal injections of bevacizumab and developed infectious endophthalmitis. Polymerase chain reaction of an aqueous humor sample showed that the endophthalmitis was caused by S. epidermidis. The patient received intravitreal ceftazidime and vancomycin, and subconjunctival injection of vancomycin. After the intravitreal injections he was treated with topical levofloxacin and cefmenoxime hydrochloride, and intravenous cefpirome. Subsequently, the ocular inflammation gradually decreased and his visual acuity remained at 30/200.

Conclusions:

Our findings indicate that endophthalmitis can develop after intravitreal bevacizumab injections. Polymerase chain reaction is useful for differentiation from sterile endophthalmitis.

Splenic abscess caused by Lactobacillus paracasei

Splenic abscess is relatively uncommon. Infections caused by lactobacilli, which are usually one of the constituents of normal flora of human gut and vagina, are also very uncommon. Here we report a case of splenic abscess caused by Lactobacillus paracasei. We performed a literature review for this rare entity. Immunocompromised status of the patient, who had uncontrolled diabetes, could have contributed to the pathogenesis of this rare disease.

Recurrent vascular catheter-related bacteremia caused by Delftia acidovorans with different antimicrobial susceptibility profiles

An 11-year-old girl with metastatic neuroblastoma developed recurrent bacteremia during sustained neutropenia after autologous peripheral blood transplantation. All febrile episodes of bacteremia were caused by single Delftia acidovorans strain revealed by ERIC-PCR. This strain became resistant to broad-spectrum penicillins and cephalosporins through antibiotic treatments. Removal of the indwelling vascular catheter resulted in resolution of the infection. So far as we know, this is the first report of vascular catheter-related D. acidovorans bacteremia in Japan.

[A case of co-existent disseminated Mycobacterium avium infection and non-Hodgkin's lymphoma]

A 76-year-old man was admitted to our hospital with dyspnea. Chest CT revealed bronchial stenosis caused by mediastinal lymphadenopathy. An FDG-PET scan showed increased FDG uptake in the mediastinal lymph nodes, lumbar vertebrae and left ilium. Neither the first biopsy specimen from the left ilium nor the endobronchial lesion showed malignant cells, but both were positive on acid-fast bacillus staining. Genetic testing found the Mycobacterium avium (MAC) gene. Therefore, we diagnosed disseminated MAC infection, and started antibiotic therapy. However, he did not respond to the therapy, and his bronchial stenosis worsened. We performed a biopsy of the newly-appearing supraclavicular lymph node, and of the left ilium again, and confirmed a new diagnosis; diffuse large B cell lymphoma, coexistent with disseminated MAC infection. This case suggests not only the simultaneous occurrence of disseminated MAC infection and diffuse large B cell lymphoma, but also the coexistence of both diseases within the same organs, and that there may be some relationship between the two diseases.

[First case report of respiratory infection with Rothia aeria]

A 53-year-old woman was admitted to our hospital with dysbasia and forgetfulness. Her past history included uveitis at age 39. Medical examinations led to a diagnosis of neurosarcoidosis. Although she was treated with prednisolone, her symptoms remained, so she received steroid pulse therapy twice, and administration of azathioprine. In early January 2007, a chest X-ray film showed nodules in the right upper lung that rapidly increased in size and number. A CT scan revealed multiple nodules including cavitary lesions in both lung fields. Examination of bronchial lavage fluid and a transbronchial lung biopsy showed a mycelium-like gram-negative filament. After the treatment with benzylpenicillin for 1 month, her laboratory data and radiological abnormalities markedly ima proved. However, switching to oral administration of amoxicillin caused the regrowth of the nodules. She was retreated with intravenous benzylpenicillin for 8 weeks, followed by oral administration of amoxicillin for 5 months, and her condition completely resolved. The causative organism was identified as Rothia aeria (described in 2004) by 16S rRNA gene sequencing. This is the first report of a case of pulmonary infection with this species.

Pleuritis caused by Campylobacter jejuni subspecies jejuni in a patient undergoing long-term hemodialysis

A 73-year-old female hemodialysis patient experienced fever, shortness of breath on effort, and chest discomfort. A decrease in breath sounds in the right lung field, leukocytosis, elevated CRP level, and a right massive pleural effusion were observed. The patient was diagnosed with bacterial pleuritis based on leukocyte-predominant exudative pleural effusion, and treated with ceftriaxone. Her symptoms, however, were not improved, so thoracic drainage was attempted. Campylobacter species were isolated from cultured pleural fluid samples, and Campylobacter jejuni subspecies jejuni was detected on the multiplex PCR assay. The antibiotic was therefore changed to minocycline following pazufloxacin, and her symptoms were improved.

Abscess formation due to Mycoplasma hominis infection after cesarean section

A 27-year-old female patient underwent cesarean section and a postoperative hematoma occurred at the site of the uterine incision. The patient underwent relaparotomy to remove the hematoma. Four days later she developed a fever of over 39 degrees C and an abscess had formed at the site. Despite therapy with several antimicrobial agents, her fever persisted. Consequently, she underwent transvaginal abscess drainage, after which she promptly became afebrile. Mycoplasma hominis was considered to be the primary causative organism. There are two reasons that could explain why the wound infection became serious: (i) M. hominis is resistant to several antimicrobial agents that are usually used to treat obstetric infections; and (ii) a long time is required to identify the pathogen. In conclusion, M. hominis should be considered as a causative organism if an antimicrobial-resistant infection occurs at the surgical site after a cesarean section.

Mycobacterium kyorinense sp. nov., a novel, slow-growing species, related to Mycobacterium celatum, isolated from human clinical specimens

A novel, non-pigmented, slow-growing mycobacterium was identified on the basis of biochemical and nucleic acid analyses, as well as growth characteristics. Three isolates were cultured from clinical samples (two from sputum and one from pus in lymph nodes) obtained from three immunocompetent patients with infections. Bacterial growth occurred at 28-42 degrees C on Middlebrook 7H11-OADC agar. The isolates showed negative results for Tween hydrolysis, nitrate reductase, semiquantitative catalase, urease activity, 3 day arylsulfatase activity, pyrazinamidase, tellurite reduction and niacin accumulation tests, but positive results for 14 day arylsulfatase activity and heat-stable catalase tests. The isolates contained alpha-, keto-, and dicarboxymycolates in their cell walls. Sequence analysis revealed that all isolates had identical, unique 16S rRNA sequences. Phylogenetic analysis of the 16S rRNA, rpoB, hsp65 and sodA gene sequences confirmed that these isolates are unique but closely related to Mycobacterium celatum. DNA-DNA hybridization of the isolates demonstrated less than 50 % reassociation with M. celatum and Mycobacterium branderi. On the basis of these findings, a novel species designated Mycobacterium kyorinense sp. nov. is proposed. The type strain is KUM 060204(T) (=JCM 15038(T)=DSM 45166(T)).

An autopsy case of Erysipelothrix rhusiopathiae endocarditis

A 58-year-old man was admitted to our hospital with fever. The vegetation was confirmed by echocardiography on the tricuspid valve and Erysipelothrix rhusiopathiae was isolated by blood culture. The patient died due to heart failure, and tricuspid valve vegetation was confirmed on autopsy and the sample of Gram's staining showed gram-positive microcolonies. Although about 60 cases of E. rhusiopathiae endocarditis have been reported, Japanese cases are extremely rare.

Suture-related keratitis caused by Corynebacterium macginleyi

We report two cases of suture-related keratitis following penetrating keratoplasty. In both cases, Corynebacterium macginleyi was isolated from corneal specimens. Scanning electron microscopy revealed that corynebacteria could aggregate and form a biofilm. The MICs of sulbenicillin and fluoroquinolones were high for both isolates. Our findings show that C. macginleyi can cause keratitis with biofilm formation.

[Anaerobiospirillum succiniciproducens septicemia]

We report the first case of septicemia caused by anaerobic spiral-shaped Gram negative bacilli, Anaerobiospirillum succiniciproducens in Japan. A 71-year-old male who had been suffered from terminal stage of liver cirrhosis and hepatocelluler carcinoma was admitted to our hospital for his symptoms of general malaise and increasing ascites on September 1, 2004. He developed diarrhea seven times a day on the eighth hospital day and had fever of 38.7 degrees C with WBC 12,600/microl and CRP 6.6 mg/dl on the next day. Blood culture grew Gram negative spiral bacilli. We initially could not identify the offending bacterium that resembled to Campyrobacter morphologically using commercially available indentification kits. However, 16SrRNA sequencing test revealed 100% compatibility with Anaerobiospirillum succiniciproducens.

Use of the novel phylogenetic marker dnaJ and DNA-DNA hybridization to clarify interrelationships within the genus Aeromonas

The interrelationships of 27 Aeromonas strains were investigated using dnaJ sequences and DNA-DNA hybridization. dnaJ sequence similarities showed a stronger relationship with DNA-DNA relatedness values than did 16S rRNA gene sequence similarities. Additionally, dnaJ sequence analysis, with interspecies divergence over 5.2 % in most cases, gave better resolution than 16S rRNA gene sequences for the differentiation of strains at the species level. Relationships among Aeromonas species were therefore elucidated on the basis of dnaJ sequences and DNA-DNA reassociation. Strains of Aeromonas encheleia and Aeromonas sp. HG11 were unquestionably grouped in the same genetic species, since they shared 98.7 % dnaJ sequence similarity and 82-85 % genomic relatedness. The phylogenetically close relationships obtained from dnaJ sequence analysis (1.7-3.3 % genetic distance) were corroborated by high DNA-DNA relatedness (73-97 %) to support the previous suggestion that Aeromonas culicicola and Aeromonas allosaccharophila are later heterotypic synonyms of Aeromonas veronii. Our findings will contribute to the clarification of controversial relationships in the genus Aeromonas and also demonstrate that analysis of dnaJ sequences can be a powerful tool for interspecies study of the genus.

Evaluation of the invader assay with the BACTEC MGIT 960 system for prompt isolation and identification of mycobacterial species from clinical specimens

Rapid and accurate identification of mycobacterial species is essential for patient management. We describe the use of the Invader assay in conjunction with the BACTEC MGIT 960 system that together provide an efficient procedure for clinical use. This assay discriminates single-base differences (e.g., genotyping single-nucleotide polymorphisms) under homogeneous and isothermal conditions and can measure directly on genomic DNA without prior target DNA amplification. To identify a wide variety of mycobacterial species, 20 Invader probes were designed to target the 16S rRNA gene and the 16S-23S rRNA gene internal transcribed spacer 1 (ITS-1) region. To validate the Invader probes, we used 78 ATCC strains, and 607 clinical mycobacterial strains, which were identified by DNA sequencing of the 16S rRNA gene and ITS-1. The Invader assay could accurately identify and differentiate these strains according to target sequences. Moreover, it could detect and identify 116 (95.1%) of 122 positive liquid cultures from the BACTEC MGIT 960 system and did not react to 83 contaminated MGIT cultures. Species identification takes 6.5 h by the Invader assay: 2.0 h for DNA extraction, 0.5 h for handling, and up to 4 h for the Invader reaction. The Invader assay has the speed, ease of use, and accuracy to be an effective procedure for the bacteriological diagnosis of mycobacterial infections.