Super acute-onset disseminated BCG infection: A case report.

Intravesical Bacillus Calmette-Guérin (BCG) instillation is an established immunotherapy for superficial bladder cancer. Herein, we describe a case of disseminated BCG infection that developed immediately after the first BCG injection. A 76-year-old man diagnosed with non-invasive bladder cancer underwent intravesical BCG instillation; he developed high fever and systemic arthralgia later that night. General examination did not reveal any infectious sources, and a combination therapy of isoniazid, rifabutin, and ethambutol was initiated after collecting his blood, urine, bone marrow, and liver biopsy samples for mycobacterial cultures. Three weeks later, Mycobacterium bovis was detected in the urine and bone marrow samples, and pathological investigation of liver biopsy revealed multiple small epithelial granulomas with focal multinucleated giant cells, leading to a diagnosis of disseminated BCG infection. The patient recovered after long-term antimycobacterial therapy without remarkable sequelae. Most cases of disseminated BCG infection occur after several doses of BCG injections, and its onset reportedly varies among cases, ranging from a few days to several months. The present case was notable as disease onset was observed only a few hours after the first BCG injection. Although rare, development of disseminated BCG infection should be considered as a differential diagnosis in patients at any time after intravesical BCG instillation therapy.

Buruli ulcer caused by Mycobacterium ulcerans subsp. shinshuense: A case report.

Buruli ulcer is the third most common mycobacterial infection worldwide and is mainly diagnosed in tropical regions. Globally, this progressive disease is caused by Mycobacterium ulcerans; however, Mycobacterium ulcerans subsp. shinshuense, an Asian variant, has been exclusively identified in Japan. Because of insufficient clinical cases, the clinical features of M. ulcerans subsp. shinshuense-associated Buruli ulcer remain unclear. A 70-year-old Japanese woman presented with erythema on her left backhand. The skin lesion deteriorated without an apparent etiology of inflammation, and she was referred to our hospital 3 months after disease onset. A biopsy specimen was incubated in 2% Ogawa medium at 30 °C. After 66 days, we detected small yellow-pigmented colonies, suggesting scotochromogens. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI Biotyper; Bruker Daltonics, Billerica, MA, USA) indicated that the organism was Mycobacterium pseudoshottsii or Mycobacterium marinum. However, additional PCR testing for the insertion sequence 2404 (IS2404) was positive, suggesting that the pathogen was either M. ulcerans or M. ulcerans subsp. shinshuense. Further examination by 16S rRNA sequencing analysis, focusing on nucleotide positions 492, 1247, 1288, and 1449-1451, we finally identified the organism as M. ulcerans subsp. shinshuense. The patient was successfully treated with 12 weeks of clarithromycin and levofloxacin treatment. Mass spectrometry is the latest microbial diagnostic method; however, it cannot be used to identify M. ulcerans subsp. shinshuense. To accurately detect this enigmatic pathogen and uncover its epidemiology and clinical characteristics in Japan, more accumulation of clinical cases with accurate identification of the causative pathogen is essential.

Susceptibility of ceftolozane/tazobactam against multidrug-resistant and carbapenem-resistant Pseudomonas aeruginosa.

Ceftolozane (CTLZ) is a novel cephalosporin antibiotic that exhibits broad-spectrum activity against gram-negative pathogens, including Pseudomonas aeruginosa, especially when combined with tazobactam (TAZ). We examined the minimum inhibitory concentration (MIC) of CTLZ/TAZ for 21 multidrug-resistant P. aeruginosa (MDRP) and eight carbapenem-resistant P. aeruginosa (CRPA) strains isolated at Okayama University Hospital, Japan. Consequently, 81% (17/21) of the MDRP strains and 25% (2/8) of the CRPA strains were resistant to CTLZ/TAZ (MIC >8 µg/mL). All 18 blaIMP-positive strains showed resistance to CTLZ/TAZ, whereas the drug retained in vitro susceptibility in 54.5% (6/11 strains) of blaIMP-negative strains.

Vancomycin MIC creep progresses in methicillin-resistant Staphylococcus aureus despite the national antimicrobial stewardship campaign: Single facility data in Japan.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of nosocomial and community infections, and vancomycin (VCM) is widely recommended as a first-line therapeutic drug. Minimum inhibitory concentrations (MICs) of VCM ≤2 µg/mL are defined as susceptible, but increases in these levels, known as "VCM MIC creep" have been reported. The aim of this study was to investigate VCM MIC creep during the promotion of a national antimicrobial stewardship campaign. METHODS: We collected data from 2013 to 2020 on S. aureus isolated at the clinical microbiology laboratory at Okayama University Hospital, Japan. We calculated the annual proportions of MRSA isolation rates by MIC levels for nosocomial and community samples and estimated annual percentage changes in the antimicrobial use density of the VCM. RESULTS: Of the 1,716 MRSA isolates, no strains showed intermediate or resistant ranges of VCM MIC levels. By 2020, the proportion of MRSA with an MIC of ≤0.5 µg/mL decreased to 35.4%, while that with an MIC of 1 µg/mL increased to 64.1% over time. The annual percentage changes of the VCM antimicrobial use density significantly increased without any trend change point (average 8.1%, p = 0.035). There was no clear correlation between the VCM AUD and annual proportion of nosocomial MRSA with MIC 1 µg/mL (correlation coefficient 0.48; p value = 0.24). CONCLUSION: We demonstrated a deteriorating situation of VCM MIC creep among MRSA strains isolated at our university hospital during the national antimicrobial stewardship campaign.