Pintip Pongpech

Gonococcal Antimicrobial Susceptibility and Prevalence of blaTEM-1, blaTEM-135 Genes in Thailand

We studied the antimicrobial susceptibility and prevalence of the blaTEM-1 and blaTEM-135 genes in Neisseria gonorrhoeae isolates obtained in Thailand. The isolates were tested using the disk diffusion method, and 100% of 370 isolates were found susceptible to cefixime, ceftriaxone, cefotaxime, ceftazidime, cefepime, spectinomycin, and azithromycin. Some of the isolates were resistant to penicillin (85.7%), ciprofloxacin (88.0%), ofloxacin (97.4%), or tetracycline (89.1%). Penicillinase-producing N. gonorrhoeae accounted for 83.8% of isolates, with 70.0% of these further identified as penicillinase-producing plus tetracycline resistant N. gonorrhoeae. Penicillin, tetracycline, and ciprofloxacin are not recommended for treatment because of the high prevalence (89.7%) of multidrug resistant gonococci. A study of genes controlling enzyme of beta-lactamase production (blaTEM-1 and blaTEM-135) was performed using mismatch amplification mutation assay PCR method and DNA sequencing. Beta-lactamase positive N. gonorrhoeae carried blaTEM-1 (69.6%) and blaTEM-135 (30.4%), indicating that there is a significant increase and spread of blaTEM-135 among gonococci in Thailand.

Prevalence and drug susceptibility of Salmonella isolated from patients in Bangkok, Thailand

Salmonella is a public health problem in many parts of the world, especially in developing countries. Globally, non-typhoidal Salmonella causes 93.8 million diarrhoeal illnesses and 155 000 deaths each year [1]. In 2010, Salmonella caused 3.4 million invasive infections and 681 000 deaths. The most widely reported serotypes are Salmonella enterica serotype Enteritidis and S. enterica serotype Typhimurium [1]. There are >2500 serovars and >50 serogroups of Salmonella [2]. The drugs of choice for treatment are extended-spectrum cephalosporins in children and fluoroquinolones in adults. We aimed to determine the serogroups, serotypes and antimicrobial susceptibility of Salmonella isolated from patients in Bangkok Thailand. A total of 728 non-duplicate Salmonella isolates were collected from different patients during January 2011 to April 2013. This study was conducted at Siriraj Hospital (Bangkok, Thailand), Thailand’s largest university-based tertiary care centre with 2600 beds and 100 000 annual admissions. Multiple isolates from different sites in the same patient were included only once. At the time of positive Salmonella isolation, 35.7% of isolates were from outpatients and 64.3% were from inpatients. The mean standard deviation age of patients was 31.34 27.89 years (range 3 days to 95 years), with a male to female ratio of 1.1:1 (51.8% males and 48.2% females). The occurrence of salmonellosis in different age groups was as follows: 60 years, 20.1%; <1 year, 17.6%; and 1–9 years, 17.5%, accounting for 55.2% of all patients. Serogroups were determined by slide agglutination using Salmonella polyvalent A–I antisera reagent and specific Salmonella antisera serogroups, including A, B, C, C1, C2, D, Vi, E, F, I, G and H (Oxoid Ltd., Basingstoke, UK). Serovars were determined for 146 available blood isolates by slide agglutination using specific Salmonella H-antisera and the Sven Gard method (S&A Reagents Lab Ltd., Bangkok, Thailand). Testing was conducted by the Kauffman–White scheme [2]. Antimicrobial susceptibility testing was performed by the disk diffusion method [3]. Escherichia coli ATCC 25922 was used as a control strain. Salmonella were mostly isolated from faeces (506; 69.5%) and blood (176; 24.2%), accounting for 93.7% of all isolates (Table 1). Salmonella serogroup B (33.4%) was predominant and was mostly found in faeces. In antimicrobial susceptibility testing, serogroup C1 had the lowest sensitivity both to ceftriaxone (14.9%) and cefotaxime (15.2%). For serotyping, the 146 available blood isolates were distributed into 27 serotypes. Salmonella Choleraesuis (34.2%) was the most common serotype, and S. Enteritidis (31.5%) ranked second, accounting for 65.8% of all isolates. Salmonella Typhi was not found. Salmonella Choleraesuis demonstrated higher drug resistance than S. Enteritidis. For