The Japanese Society of Chemotherapy (JSC) conducted the first nationwide surveillance of bacterial respiratory pathogens during the period from January to August 2006. With the cooperation of 32 medical institutions throughout Japan, a total of 924 strains belonging to seven clinically relevant bacterial species were collected from adult patients with well-diagnosed respiratory tract infections (RTIs). Antimicrobial susceptibility testing of the 887 evaluable strains (205 Staphylococcus aureus, 200 Streptococcus pneumoniae, 9 Streptococcus pyogenes, 165 Haemophilus influenzae, 91 Moraxella catarrhalis, 74 Klebsiella pneumoniae, and 143 Pseudomonas aeruginosa) to 42 antibacterial agents was conducted at the Central Laboratory of the Research Center for Anti-infective Drugs of the Kitasato Institute, according to recommendations issued by the Clinical and Laboratory Standards Institute (CLSI). The antibacterial agents employed were 25 beta-lactams, three aminoglycosides, four macrolides (including one azalide and one ketolide), one lincosamide, one tetracycline, two glycopeptides, five fluoroquinolones, and one oxazolidinone. The incidence of methicillin-resistant S. aureus (MRSA) was 63.4%, and the incidences of penicillin-intermediately resistant S. pneumoniae (PISP) and penicillin-resistant S. pneumoniae (PRSP) were 35.0% and 4.0%, respectively. Among H. influenzae, 21.2% of the strains were found to be beta-lactamase-nonproducing ampicillin (ABPC)-intermediately resistant (BLNAI), 29.1% to be beta-lactamase-nonproducing ABPC-resistant (BLNAR), and 4.8% to be beta-lactamaseproducing ABPC-resistant (BLPAR) strains. The incidence of extended-spectrum beta-lactamase-producing K. pneumoniae was 2.7% (2 of 74 strains). Three (2.1%) of the 143 P. aeruginosa strains were found to be metallo-beta-lactamaseproducing, including 1 (0.7%) multidrug-resistant strain. Through the nationwide surveillance, we obtained fundamental antimicrobial susceptibility data of clinically relevant bacterial pathogens in adult RTI to various antibacterial agents. These data will be a useful reference for future periodic surveillance studies, as well as for investigations to control antimicrobial-resistant pathogens.

For the purpose of nationwide surveillance of the antimicrobial susceptibility of bacterial respiratory pathogens collected from patients in Japan, the Japanese Society of Chemotherapy conducted a third year of nationwide surveillance during the period from January to April 2008. A total of 1,097 strains were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections. Susceptibility testing was evaluable with 987 strains (189 Staphylococcus aureus, 211 Streptococcus pneumoniae, 6 Streptococcus pyogenes, 187 Haemophilus influenzae, 106 Moraxella catarrhalis, 126 Klebsiella pneumoniae, and 162 Pseudomonas aeruginosa). A total of 44 antibacterial agents, including 26 β-lactams (four penicillins, three penicillins in combination with β-lactamase inhibitors, four oral cephems, eight parenteral cephems, one monobactam, five carbapenems, and one penem), three aminoglycosides, four macrolides (including a ketolide), one lincosamide, one tetracycline, two glycopeptides, six fluoroquinolones, and one oxazolidinone were used for the study. Analysis was conducted at the central reference laboratory according to the method recommended by the Clinical and Laboratory Standard Institute (CLSI). The incidence of methicillin-resistant S. aureus (MRSA) was as high as 59.8%, and those of penicillin-intermediate and penicillin-resistant S. pneumoniae (PISP and PRSP) were 35.5 and 11.8%, respectively. Among H. influenzae, 13.9% of them were found to be β-lactamase-non-producing ampicillin (ABPC)-intermediately resistant (BLNAI), 26.7% to be β-lactamase-non-producing ABPC-resistant (BLNAR), and 5.3% to be β-lactamase-producing ABPC-resistant (BLPAR) strains. A high frequency (76.5%) of β-lactamase-producing strains was suspected in Moraxella catarrhalis isolates. Four (3.2%) extended-spectrum β-lactamase-producing K. pneumoniae were found among 126 strains. Four isolates (2.5%) of P. aeruginosa were found to be metallo β-lactamase-producing strains, including three (1.9%) suspected multidrug-resistant strains showing resistance to imipenem, amikacin, and ciprofloxacin. Continual national surveillance of the antimicrobial susceptibility of respiratory pathogens is crucial in order to monitor changing patterns of susceptibility and to be able to update treatment recommendations on a regular basis.

For the purpose of a nationwide surveillance of the antimicrobial susceptibility of bacterial respiratory pathogens in patients in Japan, the Japanese Society of Chemotherapy conducted their second year survey, during the period from January to August, 2007. A total of 1178 strains were collected from clinical specimens obtained from adult patients with well-diagnosed respiratory tract infections. Susceptibility testing was evaluable for 1108 strains (226 Staphylococcus aureus, 257 Streptococcus pneumoniae, 6 Streptococcus pyogenes, 206 Haemophilus influenzae, 120 Moraxella catarrhalis, 122 Klebsiella pneumoniae, and 171 Pseudomonas aeruginosa). A total of 44 antibacterial agents, including 26 beta-lactams (four penicillins, three penicillins in combination with beta-lactamase inhibitors, four oral cephems, eight parenteral cephems, one monobactam, five carbapenems, and one penem), three aminoglycosides, four macrolides (including ketolide), one lincosamide, one tetracycline, two glycopeptides, six fluoroquinolones, and one oxazolidinone were used for the study. Analysis was conducted at the central reference laboratory according to the method recommended by the Clinical and Laboratory Standards Institute (CLSI). The incidence of methicillinresistant Staphylococcus aureus (MRSA) was high, at 59.7%, and the incidences of penicillin-intermediateresistant and -resistant Streptococcus pneumoniae (PISP and PRSP) were 30.4% and 5.1%, respectively. Among Haemophilus influenzae strains, 19.9% of them were found to be beta-lactamase-non-producing ampicillin (ABPC)-intermediately-resistant (BLNAI), 29.1% to be beta-lactamasenon-producing ABPC-resistant (BLNAR), and 6.7% to be beta-lactamase-producing ABPC-resistant (BLPAR) strains. Extended-spectrum beta-lactamase-producing Klebsiella pneumoniae was not isolated. Two isolates (1.2%) of Pseudomonas aeruginosa were found to be metallo-beta-lactamase-producing strains, including one (0.6%) suspected multidrug-resistant strain showing resistance to imipenem, amikacin, and ciprofloxacin. These data will be a useful reference for future periodic surveillance studies and for investigations to control resistant infections as well. Continued surveillance is required to prevent the further spread of these antimicrobial resistances.

Background:In Japan, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is used as a simple and accurate method for mycobacterial identification, but existing pretreatment techniques are time-consuming and laborious. Objective:We characterized a new pretreatment technique that extracts proteins using ultrasonic disruption. Methods:We compared this new technique with the current pretreatment method and examined the usefulness of ultrasonication, including its use in mycobacterial inactivation. A total of 174 mycobacterial isolates were tested, including 50 Mycobacterium tuberculosis complex strains, 57 Mycobacterium avium strains, 55 Mycobacterium intracellulare strains, and 12 Mycobacterium kansasii strains. The ultrasonic pretreatment method was performed with or without heat-pretreatment at 95°C for 30 minutes, in parallel with the current conventional method. For all tested strains, the mycobacterial identification agreed when comparing the new and conventional methods. Results:Samples prepared by ultrasonication without heat pretreatment exhibited multiple significant differences when compared with samples prepared by ultrasonication with heat pretreatment or by conventional methods. However, most scores were over 2.0, and the lowest score exceeded 1.7. Furthermore, the new techniques could be performed in only 10 minutes for diagnosis. In addition, we confirmed that 1 minute of ultrasonic pretreatment yielded complete inactivation of M. tuberculosis complex strains. Conclusion:The more rapid technique of protein extraction/inactivation by ultrasonication without heat pretreatment is expected to be highly useful in clinical laboratory settings.