Nationwide surveillance of the antimicrobial susceptibility of Chlamydia trachomatis from male urethritis in Japan: Comparison with the first surveillance report

The Urogenital Sub-committee and the Surveillance Committee of the Japanese Society of Chemotherapy, The Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology conducted the second nationwide surveillance of the antimicrobial susceptibility of Chlamydia trachomatis. In this second surveillance study, clinical urethral discharge specimens were collected from patients with urethritis in 26 hospitals and clinics from May 2016 to July 2017. Based on serial cultures, the minimum inhibitory concentration (MIC) could be determined for 41 isolates; the MICs (MIC₉₀) of ciprofloxacin, levofloxacin, tosufloxacin, sitafloxacin, doxycycline, minocycline, erythromycin, clarithromycin, azithromycin and solithromycin were 2 μg/ml (2 μg/ml), 1 μg/ml (0.5 μg/ml), 0.25 μg/ml (0.25 μg/ml), 0.125 μg/ml (0.063 μg/ml), 0.125 μg/ml (0.125 μg/ml), 0.25 μg/ml (0.25 μg/ml), 0.031 μg/ml (0.031 μg/ml), 0.25 μg/ml (0.125 μg/ml), and 0.016 μg/ml (0.008 μg/ml), respectively. In summary, this surveillance project did not identify any strains resistant to fluoroquinolone, tetracycline, or macrolide agents in Japan. In addition, the MIC of solithromycin was favorable and lower than that of other antimicrobial agents. However, the MIC of azithromycin had a slightly higher value than that reported in the first surveillance report, though this might be within the acceptable margin of error. Therefore, the susceptibility of azithromycin, especially, should be monitored henceforth.

[Extended-spectrum beta-lactamase (ESBL) produced by Escherichia coli and Klebsiella pneumoniae isolated from Teikyo University Hospital--the second report]

We studied the high-level resistant to cefotaxime (CTX, MIC > or = 512 micrograms/ml) clinical isolates of Escherichia coli and Klebsiella pneumoniae in Teikyo University Hospital. The CTX-resistance could be transferred to E. coli K-12 chi 1037 or ML4903 strains from 30 of the 33 isolates by conjugation at a frequency of 10(-4). When the hydrolysis rate of benzylpenicillin was 100%, the beta-lactamases which were extracted from the transconjugants hydrolyzed CTX, CAZ and AZT at the rate of 38-95%, 0-8.6% and 0-56%, respectively. These results demonstrate that these enzymes should be categorized into ESBL. The nucleotide sequence of CTX-resistant gene was identified to that of the CTX-M2 gene which was first described in Argentina. It was found to have 99.9% homology to Toho-1 gene in Japan and 99.6% homology to CMY-2 gene. Using a PCR methods for the detection of one of ESBL gene such as CTX-M2, Toho-1 or CMY-2, the DNA was amplified from all strains (11 isolates of E. coli and 21 isolates of K. pneumoniae).

[Extended-spectrum beta-lactamase (ESBL) produced by Escherichia coli and Klebsiella pneumoniae isolated from Teikyou University Hospital--the first report]

We studied the cefotaxime (CTX)-resistant (MIC > or = 32 micrograms/ml) clinical isolates of E. coli and K. pneumoniae in Teikyo University Hospital from 1990 to 1996. The incidence of CTX-resistant isolates was 0.4% (6/1,282) in E. coli and 0.6% (7/1,044) in K. pneumoniae, in 1990. In 1995, the incidence of CTX-resistance increased to 1.7% (50/2,910) in E. coli (p = 0.0013) and 7.2% (144/1,996) in K. pneumoniae (p < 0.0001). These species have been detected in the stool (86 isolates), urine (59 isolates), sputum (15 isolates), pus (15 isolates), throat (10 isolates) and others (12 isolates) in 1995. MIC50 of ampicillin (ABPC), ABPC with clavlanic acid (CVA) 5 micrograms/ml, piperacillin (PIPC), PIPC with CVA 5 micrograms/ml, ceftazidime, CTX, ceftizoxime, cefpodoxime, cefepime, aztreonam, cefmetazole, latamoxef, and imipenem used against 33 isolates (11 isolates of E. coli, 22 isolates of K. pneumoniae), which were detected in 1996-1997, was > 512 micrograms/ml, 8 micrograms/ml, > 512 micrograms/ml, 8 micrograms/ml, 4 micrograms/ml, > 512 micrograms/ml, 16 micrograms/ml, > 512 micrograms/ml, 256 micrograms/ml, 32 micrograms/ml, 2 micrograms/ml, 0.25 microgram/ml and 0.25 microgram/ml, respectively. This susceptibility pattern were very similar to the Toho-1 type beta-lactamases producing strains.

Surgical management of aortic regurgitation associated with ventricular septal defect

Surgical treatment for congenital aortic regurgitation (AR) with ventricular septal defect (VSD) in pediatric patients carried out between 1979 and 1994 was reviewed. Aortic commissural valvuloplasty (AVP) was performed on prolapsed cusps in 34 patients (mean age 6.3 +/- 3.3 years (range: 2 to 24 years) with AR and VSD. The preoperative grade of AR was 2.6 +/- 0.8 measured angiographically by Sellers' classification. Patients had greater than moderate AR in conjunction with subpulmonary (n = 16), perimembranous (n = 15) or mixed type VSD (n = 3). In total, 25 right coronary cusps (RCC), five non-coronary cusps (NCC) and one left coronary cusp were repaired. In two cases, both RCC and NCC were plicated. One case had bicuspid valve and both cusps were repaired. There were no operative or late deaths. Moreover, the AR grade of the 25 cases has been below mild during a mean of 11.3 years follow up, though seven cases (22%) have developed above moderate AR. The two cases with persistent AR required redo AVP, with one having aortic valve replacement eventually after redo surgery. The operative findings showed cusp perforation on the repair site, or cusp elongation. However, the overall event-free rate analyzed by the Kaplan-Meier method was sufficiently favorable, with 96.6 +/- 3.4% for 5 years and 92.8 +/- 4.9% for 10 years. We conclude that aortic valvuloplasty for aortic regurgitation and VSD in pediatric patients is beneficial, with low mortality and reoperation rates.