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Objectives: This systematic review and meta-analysis synthesized the evidence from randomized controlled trials comparing vitamin D and placebo in reducing depressive symptoms and contributing to all-cause dropout rates., Methods: Inclusion criteria were randomized controlled trials comparing reduced depression between depressed patients receiving vitamin D and those receiving placebo. We searched PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials through January 2022., Results: Eighteen trials (1980 participants, median age 39 y) were included in the meta-analysis. Vitamin D supplements were significantly superior to placebo in reducing depression (standardized mean difference = -0.49; 95% confidence interval [CI], -0.75 to -0.23; I 2 = 81%). Depressed adults (standardized mean difference = -0.70; 95% CI, -1.09 to -0.31) responded to vitamin D significantly better than children and adolescents (standardized mean difference = 0.10; 95% CI -0.27 to 0.47). Vitamin D administered as bolus doses (oral intermittent high doses or intramuscular single high dose) appeared to be more effective than that taken daily by the oral route (P < 0.01). Patients with more severe depression tended to respond better than those with less severity (P = 0.053). We found no moderating effect of concurrent antidepressant use, presence of major depressive disorder diagnosis, physical comorbidity, sex, duration and doses of vitamin D supplement, serum 25-hydroxyvitamin D levels at baseline, and changes in serum 25-hydroxyvitamin D levels in the vitamin D group. Dropout rates were indifferent between the groups (17 trials; risk ratio = 0.84; 95% CI, 0.6-1.16; I 2 = 0)., Conclusions: Heterogeneous data suggested that vitamin D supplements are effective and safe for depressed patients., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Pneumococcal serotype 35B is an important non-conjugate vaccine (non-PCV) serotype. Its continued emergence, post-PCV7 in the USA, was associated with expansion of a pre-existing 35B clone (clonal complex [CC] 558) along with post-PCV13 emergence of a non-35B clone previously associated with PCV serotypes (CC156). This study describes lineages circulating among 35B isolates in South Africa before and after PCV introduction. We also compared 35B isolates belonging to a predominant 35B lineage in South Africa (GPSC5), with isolates belonging to the same lineage in other parts of the world. Serotype 35B isolates that caused invasive pneumococcal disease in South Africa in 2005-2014 were characterized by whole-genome sequencing (WGS). Multi-locus sequence types and global pneumococcal sequence clusters (GPSCs) were derived from WGS data of 63 35B isolates obtained in 2005-2014. A total of 262 isolates that belong to GPSC5 (115 isolates from South Africa and 147 from other countries) that were sequenced as part of the global pneumococcal sequencing (GPS) project were included for comparison. Serotype 35B isolates from South Africa were differentiated into seven GPSCs and GPSC5 was most common (49 %, 31/63). While 35B was the most common serotype among GPSC5/CC172 isolates in South Africa during the PCV13 period (66 %, 29/44), 23F was the most common serotype during both the pre-PCV (80 %, 37/46) and PCV7 period (32 %, 8/25). Serotype 35B represented 15 % (40/262) of GPSC5 isolates within the global GPS database and 75 % (31/40) were from South Africa. The predominance of the GPSC5 lineage within non-vaccine serotype 35B, is possibly unique to South Africa and warrants further molecular surveillance of pneumococci.

Background: Pneumococcal disease outbreaks of vaccine preventable serotype 4 sequence type (ST)801 in shipyards have been reported in several countries. We aimed to use genomics to establish any international links between them., Methods: Sequence data from ST801-related outbreak isolates from Norway (n = 17), Finland (n = 11) and Northern Ireland (n = 2) were combined with invasive pneumococcal disease surveillance from the respective countries, and ST801-related genomes from an international collection (n = 41 of > 40,000), totalling 106 genomes. Raw data were mapped and recombination excluded before phylogenetic dating., Results: Outbreak isolates were relatively diverse, with up to 100 SNPs (single nucleotide polymorphisms) and a common ancestor estimated around the year 2000. However, 19 Norwegian and Finnish isolates were nearly indistinguishable (0-2 SNPs) with the common ancestor dated around 2017., Conclusion: The total diversity of ST801 within the outbreaks could not be explained by recent transmission alone, suggesting that harsh environmental and associated living conditions reported in the shipyards may facilitate invasion of colonising pneumococci. However, near identical strains in the Norwegian and Finnish outbreaks does suggest that transmission between international shipyards also contributed to those outbreaks. This indicates the need for improved preventative measures in this working population including pneumococcal vaccination., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [R.A.G received a PhD stipend from Pfizer 2009–2011. L.S is a co-investigator in an unrelated study, for which THL has received research funding from GlaxoSmithKline Vaccines. S.C.C: acts as principal investigator on studies conducted on behalf of University Hospital Southampton NHS Foundation Trust/University of Southampton that are sponsored by vaccine manufacturers but receives no personal payments from them. S.C.C. has participated in advisory boards for vaccine manufacturers but receives no personal payments for this work. S.C.C. has received financial assistance from vaccine manufacturers to attend conferences. All grants and honoraria are paid into accounts within the respective NHS Trusts or Universities, or to independent charities. N.K.F, C.L.S The Immunisation and Countermeasures Division, Public Health England - National Infection Service, London, UK provides vaccine manufacturers with post-marketing surveillance reports, which the Marketing Authorization Holders are required to submit to the UK Licensing authority in compliance with their Risk Management Strategy. A cost recovery charge is made for these reports. N.K.F and C.S. conduct contract research funded by vaccine manufacturers (including GlaxoSmithKline and Pfizer) on behalf of Public Health England. No personal remuneration is received. M.T reports grants from GlaxoSmithKline and Pfizer to the Finnish Institute for Health and Welfare for unrelated research projects in which she is a co-investigator. All remaining authors report no conflicts of interest.]., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

A Neisseria gonorrhoeae multilocus sequence type (MLST) ST7363 strain was isolated from a patient at the Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, in 2010 and completely sequenced. This strain is susceptible to ceftriaxone and cefixime. A complete circular chromosome and circular plasmids were assembled from combined Oxford Nanopore Technologies (ONT) and Illumina sequencing.

Background and Aim: Kaffir lime fruit peel oil and Kaffir lime leaf oil have been reported for their activities against respiratory tract pathogens. The purpose of the study was to develop clear oral sprays to be used as a first-defense oral spray., Experimental Procedure: Clear antibacterial oral sprays were prepared and analyzed for their respective active major compounds, using GC-MS. The sprays were tested against a Gr. A streptococcal clinical isolate and 3 standard respiratory tract pathogens, using Broth microdilution method. A 4-month stability test was carried out as well., Results and Conclusion: Six clear oral sprays, three formulae composed of Kaffir lime fruit peel oil (6, 10, 13%v/v KLO) and the other three formulae containing Kaffir lime leaf oil (4, 8, 12%v/v KLLO), were developed. The active compounds in KLO were α-terpineol and terpinene-4-ol whereas that in KLLO was citronellal. All oral sprays exhibited antibacterial activity against one Group A streptococcal clinical isolate and three respiratory pathogenic pathogens, Staphylococcus aureus ATCC 29213, Streptococcus pneumoniae ATCC 49619, and Haemophilus influenza e ATCC 49247, among which the strongest activity was against H. influenza e ATCC 49247. The antibacterial activity of all oral sprays remained unchanged in an accelerated stability test, at 4, 30, and 45 °C under 75% relative humidity, throughout the 4-month storage., (© 2019 Center for Food and Biomolecules, National Taiwan University. Production and hosting by Elsevier Taiwan LLC.)

We studied the antimicrobial susceptibility and prevalence of the bla TEM-1 and bla TEM-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 (bla TEM-1 and bla TEM-135 ) was performed using mismatch amplification mutation assay PCR method and DNA sequencing. Beta-lactamase positive N. gonorrhoeae carried bla TEM-1 (69.6%) and bla TEM-135 (30.4%), indicating that there is a significant increase and spread of bla TEM-135 among gonococci in Thailand.

Haemophilus influenzae was isolated from 556 different patients, mostly 10 years or under, at a tertiary referral hospital in Bangkok, Thailand during 2012 - 2015. Peak period of detection was from January to March. Thirty-nine percent of the isolates were β-lactamase positive. β-Lactamase-negative ampicillin-resistant H. influenzae (BLNAR) constituted 2% of β-lactamase-negative cases. H. influenzae was susceptible to ampicillin (58%), amoxicillin/clavulanate (99%), cefotaxime (100%), ceftriaxone (100%), cefuroxime (99%), ciprofloxacin (99%), chloramphenicol (86%), tetracycline (75%), and trimethoprim-sulphamethoxazole (52%). β-Lactamase-producing isolates (72%) showed high minimal inhibitory concentration (MIC) to ampicillin (128-516 μg/ml) and all BLNAR isolates low ampicillin MIC (2-16 μg/ml). These findings indicate that the level of ampicillin resistance in H. influenzae depended on differences in resistance mechanism.

We surveyed group C and group G β-hemolytic streptococci for emm and emmL (emm -like) genes which encode the M protein, as well as determined their antimicrobial susceptibilities. A total of 97 isolates 79 GCS/GGS isolates and 18 isolates from other groups were tested for the M protein gene by PCR. Focusing on invasive infections with group A (GAS), group C (GCS), and group G (GGS) β-hemolytic streptococci isolated from blood, the M protein gene was found in 90.0%, 84.6%, and 78.3% of isolates, respectively. The hypervariable N terminal region of the emm was sequenced from 62 isolates, and 26 types of the emm gene were identified. Based on these results, type emm222.2 may be endemic to Thailand. The results of antimicrobial susceptibility testing of groups C, G, and non-groups A to G isolates indicated high susceptibility (range 82-100%) to penicillin, cefotaxime, chloramphenicol, clindamycin, erythromycin, linezolid, ofloxacin, and vancomycin, whereas the isolates showed low susceptibility (range 0-15.6%) to tetracycline.

Neisseria gonorrhoeae is a major public health problem globally, especially because the bacterium has developed resistance to most antimicrobials introduced for first-line treatment of gonorrhea. In the present study, 96 N. gonorrhoeae isolates with high-level resistance to penicillin from 121 clinical isolates in Thailand were examined to investigate changes related to their plasmid-mediated penicillin resistance and their molecular epidemiological relationships. A β-lactamase (TEM) gene variant, bla(TEM-135), that may be a precursor in the transitional stage of a traditional bla(TEM-1) gene into an extended-spectrum β-lactamase (ESBL), possibly causing high resistance to all extended-spectrum cephalosporins in N. gonorrhoeae, was identified. Clonal analysis using multilocus sequence typing (MLST) and N. gonorrhoeae multiantigen sequence typing (NG-MAST) revealed the existence of a sexual network among patients from Japan and Thailand. Molecular analysis of the bla(TEM-135) gene showed that the emergence of this allele might not be a rare genetic event and that the allele has evolved in different plasmid backgrounds, which results possibly indicate that it is selected due to antimicrobial pressure. The presence of the bla(TEM-135) allele in the penicillinase-producing N. gonorrhoeae population may call for monitoring for the possible emergence of ESBL-producing N. gonorrhoeae in the future. This study identified a bla(TEM) variant (bla(TEM-135)) that is a possible intermediate precursor for an ESBL, which warrants international awareness.

The most frequent markers of fluoroquinolone resistance in S. pneumoniae are chromosomal mutations in the quinolone-resistance-determining regions of DNA gyrase and topoisomerase IV encoding for the gyrA, gyrB and parC, parE genes. In 2008, 6.5% of the Streptococcus pneumoniae isolates in a Bangkok university hospital were resistant to ofloxacin. Using PCR and DNA sequencing, we identified mutations in both the gyrA and parC genes of four ofloxacin- and ciprofloxacin-resistant S. pneumoniae isolates (minimum inhibitory concentrations > 32 microg/ml). Mutations were found in the gyrA gene at positions Ser81Phe, Glu85Gly, Glu85Lys and in the parC gene at position Ser79Tyr. Three isolates had mutations in both genes. Two of the isolates were serotype 6B and two were serotypes not contained in currently licensed pneumococcal vaccines. This is the first report of the mechanisms of fluoroquinolone resistance in S. pneumoniae in Thailand.

Streptococcus pneumoniae was isolated from 170 patient specimens at Siriraj Hospital during January-December 2008. Patients were 66% male and ranged in age from 3 months to 94 years (mean +/- SD = 38.2 +/- 31.7). The largest proportion (29.4%) of isolates were from patients older than 60 years, followed by patients aged 2-5 years (20%) and from patients less than 2 years (12.4%). Monthly isolation was highest in December (22 isolates in December compared to the average of 13 isolates of the other months). Antimicrobial susceptibility for eight drugs was determined by the disk diffusion method. Overall, susceptibility was generally high to chloramphenicol (71.8%), linezolid (100%), ofloxacin (93.5%) and vancomycin (100%), but less susceptible to erythromycin (35.3%), penicillin (31.1%), tetracycline (28.8%) and trimethoprim/ sulfamethoxazole (24.1%). Among the 105 (62%) isolates resistant to three or more drugs, the most common resistance pattern was erythromycin-penicillin-tetracycline-trimethoprim/sulfamethoxazole, accounting for 39% of such isolates, followed by chloramphenicol-erythromycin-penicillin-tetracycline- trimethoprim/sulfamethoxazole (29.5%). The minimal inhibitory concentrations (MIC) of penicillin and cefotaxime were determined by broth microdilution. By 2008 CLSI criteria, 92% and 90% of 51 sterile site isolates were penicillin and cefotaxime susceptible, including one of two meningitis cases. In contrast, of 26 non-sterile site isolates, only 26.9% and 76.9% were susceptible to penicillin and cefotaxime, respectively. The MICs of penicillin were higher for isolates from non-sterile sites than for those from sterile sites.

Rapid detection of bacterial pathogen causing meningitis is very important to guide antimicrobial therapy before the standard culture result is available. Other than gram stain, one of the most useful rapid methods is the detection of bacterial antigen in cerebrospinal fluid. This article reviewed the methods of bacterial antigen detection for diagnosis of meningitis as well as a microbiology aspect of this life-threatening disease.

Objective: Penicillin resistance in Streptococcus pneumoniae isolates results from altered penicillin-binding proteins (PBPs), especially PBP2, which has a reduced affinity to penicillin. This study evaluated drug resistance and the gene sequence of the conserved motif pbp2b of penicillin-resistant isolates in Thailand., Material and Method: Penicillin-resistant pneumococci with minimum inhibitory concentrations (MIC) for penicillin > or = microg/ ml and penicillin-susceptible strains were identified from clinical specimens. The pbp2b genes were amplified by polymerase chain reaction (PCR), and the purified PCR product was cloned into E. coli. The recombinant plasmid clones containing pbp2b were sequenced and evaluated for mutations corresponding to penicillin and cefotaxime resistance., Results: Penicillin-susceptible S. pneumoniae isolates were susceptible to 12 other antibiotics tested (range 95-100%) while penicillin-nonsusceptible isolates were resistant to most antibiotics except amoxicillin/clavulanate and levofloxacin. Sequence analysis of pbp2b showed a substitution of A for T451 next to the region of the SSN triad in all six resistant isolates tested and mutations clustered around the KTG triad in two isolates. Using the ClustalW alignment program, Thai isolates differed from those of European countries, but were more similar to those from Japan than Korea., Conclusion: Penicillin or cefotaxime resistance in S. pneumoniae in Thailand was due to affinity reduction of PBP2b, similar to changes found in other Asian isolates.

Acinetobacter baumannii has emerged in health care settings as a pandrug-resistant pathogen. Carbapenems are ineffective for treatment of this pathogen. Here we explored the molecular epidemiology and mechanism of carbapenem resistance in clinical isolates of carbapenem-resistant A. baumannii (CRAB). Antibiotic susceptibility by disk diffusion test was performed using imipenem and meropenem disk on 200 different clinical CRAB isolates. All isolates were resistant and gave inhibition zones of both antibiotic disks < or = 13 mm. Polymerase chain reaction (PCR) was carried out on 37 randomly selected isolates to amplify the common carbapenem hydrolyzing beta-lactamase genes (bla(OXA23)-like, bla(OXA-24/40)-like, bla(OXA-58), bla(IMP), and bla(VLM)). Clones were resolved by PCR-randomly amplified polymorphic DNA (PCR-RAPD) and plasmid profiling. PCR amplification and DNA sequencing revealed the existence of bla(OXA-23) downstream of the insertion element, ISAba1, in all 37 isolates tested. This segment was present in the carbapenem-resistant genomic resistant island AbaR4. These isolates were resolved into three RAPD types (Type I, 20 isolates; Type II, 16 isolates; and type III, 1 isolate) and 10 plasmid profiles. The CRAB isolates investigated here were oligoclonal and carbapenem resistance was conferred by the presence of bla(OXA-23). The presence of this beta-lactamase gene in many clonal isolates indicated its wide spread.

There is a growing evidence on emergence of carbapenem-resistant Acinetobacter baumannii (CRAB) in Thailand and recent treatment guidelines recommend a combination therapy using carbapenem and/or polymyxin with rifampin. Rifampin would be added in a combination therapy. The susceptibility of this pathogen to rifampin is not known, so we studied the rifampin susceptibility and possible mechanisms of resistance used by CRAB. The disk diffusion test was performed on 111 clinical isolates using 5 microg rifampin disk following CLSI guidelines. The inhibition zone was interpreted based upon the recommendation for Staphylococcus aureus (inhibition zone < 20 mm = resistant). Polymerase chain reaction (PCR) using the primers specific for arr-2 encoding rifampin ADP-ribosyltransferase was performed in all isolates. The rpoB DNA sequences from two isolates, with or without arr-2, were compared. All isolates under study were rifampin resistant. Inhibition zone was < 14 mm for all isolates. The arr-2 was positive for 35 isolates (31.5%) and these isolates correlated with high level of resistance (inhibition zone < 10mm). The DNA sequences of rpoB genes in arr-2 negative isolate showed mutations L904S, P906R, K909N and M1262K that might have roles in rifampin resistance. Mutations of rpoB genes in some isolates and possession of arr-2 in class 1 integron element were mechanisms for rifampin resistance and these resistant determinants can disseminate through both vertical and horizontal gene transfer. Under this circumstance, it is not recommended to use rifampin in the treatment of carbapenem-resistant A. baumannii in Thailand.

A total of 400 clinical Streptococcus pneumoniae strains from patients with respiratory diseases were collected from January 2002 to December 2005. In this study, an increased prevalence of penicillin-nonsusceptible S. pneumoniae (PNSP) from 63% in 2002-2003 to 69% in 2004-2005 was found. During 2004-2005, 56% were erythromycin-nonsusceptible S. pneumoniae (ENSP) and 54% were both PNSP and ENSP. The PNSP, ENSP and PNSP+ENSP groups showed similar trends, ie, sensitive to amoxicillin/clavulanate (range 97.2-98.5%), levofloxacin (range 90.7-92.4%), ceftriaxone (range 87.1-89.4%), and ofloxacin (range 64.8-66.1%). Lower levels of susceptibility were detected for azithromycin, clarithromycin, cefdinir, cefprozil, clindamycin, co-trimoxazole, chloramphenicol and tetracycline in penicillin and erythromycin-nonsusceptible strains. Of the macrolide-resistant S. pneumoniae, 55% of strains exhibited the M phenotype and 45% the constitutive MLS(B) phenotype. No pneumococci with the inducible MLS(B) phenotype were detected in Thailand.

Among 120 Escherichia coli isolates from Thai patients, 37 and 9 isolates were extended-spectrum beta-lactamase (ESBL) and suspected ESBL producers respectively while 5 E. coli isolates from 120 Thai healthy adults were suspected ESBL producers. Integrase (intl1) gene was detected in 99% of the clinical and 87% of the non-clinical isolates. Among 37 ESBL producers, percent recovery of bla(TEM), bla(CTX-M), bla(SHV) and bla(VEB) was 78%, 78%, 8% and 8%, respectively. Twenty-five isolates of ESBL producers carried both bla(TEM) and bla(CTX-M), 2 isolates carried 3 genes (bla(TEM), blac(CTX-M), and bla(SHV)) and 3 showed no detectable bla gene. Among the 14 suspected ESBL producers, intl1 and bla(TEM) were detected in 13 isolates. ESBL producers from clinical samples were resistant to most of the tested antimicrobial agents compared to non-ESBL producers and isolates from healthy adults with about half of the latter susceptible to all tested antimicrobial agents. Only one clinical isolate was resistant to imipenem. Susceptibility to trimethoprim/sulfamethoxazole among the clinical isolates in ESBL producer group (27%) and non-producer group (33%) were comparable, whereas the percent susceptibility of the non-clinical isolates was about twice that of the clinical isolates.

Objective: Extended-spectrum beta-lactamases (ESBLs) are most prevalent in Klebsiella pneumoniae. This organism is frequently isolated from clinical specimens and can cause septicemia, pneumonia or urinary tract infection. There were occasionally suspicious outbreaks of ESBL-producing K. pneumoniae in patients' wards. The objective is to determine whether the randomly amplified polymorphic DNA (RAPD), which is a polymerase chain reaction (PCR)-based typing technique, can be used as a typing method for studying the molecular epidemiology of ESBL-producing K. pneumoniae., Material and Method: The present study was carried out by using 30 ESBL-producing K. pneumoniae isolates obtained from different patients admitted to Siriraj Hospital between January and February 2004. RAPD was evaluated for three primers. All isolates were re-examined by using Southern blot hybridization., Results: It was found that 29 DNA band patterns were generated individually by either AP4 or HLWL74 and R108 primers (30 patterns) for RAPD analysis and 30 patterns for Southern blot hybridization with class 1 integron (intI1) probe. Different patterns indicated that these 30 isolates could not be the cause of an outbreak in Siriraj Hospital., Conclusion: The RAPD typing is good and can be used as a screening, rapid and inexpensive'test for ESBL-producing K. pneumoniae during investigation of outbreaks.

This is the first reported case of bacillary angiomatosis associated with Bartonella henselae in Thailand. The clinical, pathological, and microbiological findings are presented. The bacterium was isolated from a biopsy of skin lesions obtained on admission and identified by cellular morphology, characteristics of colonies on chocolate agar, extensive biochemical tests and 16S ribosomal DNA sequencing.

Roseomonas is a pink-pigmented, non-fermentative, gram-negative coccobacillus bacterium. Human infections caused by Roseomonas are very rare. We report the first case of bacteremia associated with Roseomonas gilardii subsp rosea in Thailand. The bacterium was isolated from blood culture and identified by cellular morphology, characteristics of colonies on blood agar, extensive biochemical tests and 16S ribosomal DNA sequencing.

We evaluated 582 Haemophilus influenzae isolates from patients between January 2000 and December 2004. Overall, 433 isolates were obtained from sputum and bronchial washings, 124 isolates were from pus, 19 isolates were from blood and 6 isolates form cerebrospinal fluid. H. influenzae was sensitive to amoxicillin/clavulanate, ampicillin/sulbactam, gentamicin, cefuroxime, ceftriaxone, cefotaxime, ciprofloxacin, ofloxacin, imipenem, meropenem (range 97-100%), chloramphenicol (75%), ampicillin/amoxicillin (52%), but resistant to trimethoprim-sulphamethoxazole. As for beta-lactamase production, 48.4% of the isolates tested were positive.

Background: The CA-MRSA infections have emerged in many parts of the world over the past decade. To our knowledge, the prevalence of CA-MRSA infections in Thai patients is unknown., Objective: To determine an epidemiology of Staphylococcus aureus (S. aureus) infections in hospitalized patients in Siriraj Hospital and the prevalence of infections caused by community-acquired methicillin-resistant S. aureus (CA-MRSA)., Material and Method: The study was carried out at Siriraj Hospital from January to May 2005. The eligible patients were hospitalized patients whom S. aureus were isolated from their clinical specimens submitted to Department of Microbiology. S. aureus isolate was classified into infection or colonization. S. aureus infections were further classified into methicillin-resistant S. aureus (MRSA) or methicillin-sensitive S. aureus (MSSA) infections, and hospital-acquired (HA) or community-acquired (CA) infections. CA-MRSA infection is defined as infection caused by MRSA isolated from the patient within 72-hour of hospitalization and has no features of HA MRSA infections., Results: There were 669 S. aureus isolates from 448 patients. Two hundred and sixty two patients (58.5%) were MSSA whereas 186 (41.5%) were MRSA infections. CA-MRSA was found in three isolates (0.9% of total MRSA) from two patients., Conclusion: The prevalence of CA-MRSA infections in hospitalized patients in Siriraj Hospital was uncommon and these patients could probably be HA MRSA infections.

Abstract. This study was undertaken from 1995-2000 to investigate the cause of respiratory tract infection among 481 patients with human immunodeficiency virus (HIV) at Siriraj Hospital, Bangkok, Thailand. The positive rate of bacterial pathogens was 38.46%. Pseudomonas aeruginosa appeared to be the most common pathogen (32.97%), followed by Staphylococcus aureus (18.92%), Klebsiella pneumoniae (10.81 %), Haemophilus influenzae (7.57%), and Acinetobacter baumannii (5.95%). P. aeruginosa was sensitive to netilmycin, amikacin, imipenem, meropenem, cefoperazone/sulbactam, piperacillin/tazobactam, and gentamicin (67-84%). S. aureus was sensitive to vancomycin and teicoplanin (100%).

Meningitis caused by Salmonella species is not uncommon in many developing countries. Patients suspected of bacterial meningitis who were admitted to Siriraj Hospital were enrolled in this study during 1986-2001. There were only 19 cases of Salmonella meningitis. Salmonella serogroup D ranked first, followed by serogroup C, serogroup B and then serogroup H. Most patients were children under 1 year of age. The antimicrobial susceptibility pattern for Salmonella meningitis may provide a guideline for the selection of appropriate drug treatment.

Bacterial infections in human immunodeficiency virus (HIV) infected patients may frequently develop into septicemia. Our study evaluated the bacterial pathogens isolated from hemocultures of HIV-infected patients at Siriraj Hospital and their antimicrobial susceptibility tests. The percentages of positive hemocultures were 24.64, 21.38, 23.88, and 28.46% in 1996, 1997, 1998, and 1999, respectively. Salmonella spp was the most pathogen isolated, followed by Escherichia coil (10.93%), Staphylococcus aureus (8.2%), coagulase-negative staphylococci (6.56%), nonfermentative gram-negative rods (6.01%), Pseudomonas aeruginosa (5.46%), Klebsiella pneumoniae (4.37%), and Enterobacter spp (4.37%). Salmonella, serogroup C was the most frequently isolated serogroup. It was sensitive to amoxicillin/clavulanate in 100%, ampicillin/sulbactam in 89%, cefazolin, cefuroxime, cefotaxime, ceftriaxone, ceftazidime, imipenem, gentamicin, amikacin, netilmycin, ofloxacin, and ciprofloxacin in 100%. The changing spectrum of bacteria and antimicrobial susceptibility patterns in HIV-1 infected patients may provide a guideline for the selection of appropriate drugs for treatment.

Pseudomonas aeruginosa is a leading cause of nosocomial infections. One thousand two hundred and twenty strains of mucoid and non-mucoid types of P. aeruginosa isolated from different patients were examined at Siriraj Hospital from January 2001-October 2003. The prevalences of P. aeruginosa mucoid type and non-mucoid type were 3.6% and 96.4%, respectively. Susceptibility testing was performed by Kirby-Bauer disk diffusion method as recommended by NCCLS. The isolates with mucoid phenotypes were more susceptible than the non-mucoid isolates. The antimicrobial susceptibility pattern of both types should provide guidelines for the selection of appropriate drugs for treatment.

Infective endocarditis is life-threatening and urgent treatment is needed. We review here 6217 patients with infective endocarditis admitted to Siriraj Hospital during a 20 year period, 1982-2001. In this retrospective study, we obtained our data from hemoculture results. Bacterial pathogens were found in only 834 patients (13.41%). Of the five most common pathogens, nonfermentative gram-negative rods (N.F.) ranked first (20.94%), followed by coagulase-negative staphylococci (12.47%), viridans streptococci (10.23%), Staphylococcus aureus (9.29%), and Escherichia coli (8.59%). Of the N.F., the sensitivities were: cefoperazone/sulbactam (86%), piperacillin/tazobactam (86%), meropenem (84%), imipenem (83%), ceftazidime (78%), ofloxacin (85%), ciprofloxacin (71%), and co-trimoxazole (71%).

Mycoplasma pneumoniae antibody was determined in 811 sera of different patients admitted to Siriraj Hospital with respiratory tract infection from July 1, 2000 to August 31, 2003 by agglutination with gelatin particle agglutination test kit (SERODIA-MYCO II, Fujirebio Inc. Japan) in microtiter plates. Three hundred and three sera were positive (37.36%). The five most positive titer were found in patients 5-9 yr (40.26%), followed by patients 1-4 yr (24.75%), 10-14 yr (19.80%), 30-39 yr (5.28%) and 20-29 yr (3.96%). The positive titers ranged from 40 to > 20,480. Female:male ratio in positive patients was approximately the same (1.19:1). High titers (> or = 320) were found in 146 out of 303 patients (48.18%). The infection was mostly found in children aged 5-9 yr. Detection of antibody to M. pneumoniae infection showed that 37.36% of patients who were suspected of having atypical bacterial pneumonia were positive.

The objective of the study was to compare the clinical efficacy and bacteriological response of levofloxacin and amoxicillin/clavulanic acid (co-amoxiclav) in the treatment of purulent maxillary sinusitis. Sixty patients randomly received either levofloxacin 300 mg orally once daily (LEV group) or co-amoxiclav 625 mg three times a day (COA group) for 14 days. Thirty four patients were in the LEV group and 26 patients were in the COA group. The mean total symptom score was significantly decreased after treatment and was comparable between both groups. Radiological improvement was 61.8% in the LEV group (41.2% resolution, 20.6% improvement) and 61.5% in the COA group (26.9% resolution, 34.6% improvement). Pretreatment maxillary antral aspiration cultures were positive in 28 patients (82.4%) in the LEV group and 20 patients (76.9%) in the COA group. Bacteriological eradication was 78.5% in the LEV group and 70.0% in the COA group, which was not significantly different. In the LEV group, the eradication rate for major pathogens of acute sinusitis was 100% for H. influenzae (both betalactamase +ve and -ve), 100% for S. pneumoniae and S. aureus, 100% for Neisseria species, and 66.7% for P. aeruginosa. The eradication rate in the COA group was 75% for H. influenzae (both betalactamase +ve and -ve), 100% for S. pnumoniae and S. aureus, 50% for Neisseria species, and 0% for P. aeruginosa. There were no significant changes in vital sign measurements or hemato-biochemical parameters at the end of treatment as compared to baseline values, in both groups. Adverse events were found in 8.8% of patient in the LEV group and in 7.7% of patients in the COA group. Adverse events included nausea, abdominal pain, and diarrhea. All the adverse events in both groups were mild and resolved spontaneously. This study demonstrated that levofloxacin 300 mg orally once daily was as effective and safe as amoxicillin/clavulanic acid 625 mg three times a day in the treatment of maxillary sinusitis, either acute or acute exacerbation. Both drugs showed bacteriological efficacy that was not significantly different. The once daily dosage regimen is more applicable, convenience and has better compliance.

The antibiotic susceptibility pattern of Streptococcus pneumoniae isolated from specimens of invasive infections was examined at Siriraj Hospital, a tertiary care center in Bangkok, during December 1996 April 1998. The percentage of S. pneumoniae isolates intermediate and resistant to various antibiotics were: penicillin, 25% and 21%; amoxicillin-clavulanate, 24% and 0%; cefuroxime, 6% and 36%; cefotaxime, 6% and 1.4%; ceftibuten, 5% and 42%; imipenem 22% and 0%; co-trimoxazole, 6% and 41%; chloramphenicol, 2% and 26%; erythromycin, 12% and 16%; azithromycin, 0% and 30%; and roxithromycin 0% and 33%. Most of the penicillin-nonsusceptible S. pneumoniae (PNSP) were also nonsusceptible to other antibiotics except cefotaxime, and imipenem. The isolates from respiratory specimens have a higher rate of resistance to all antimicrobial agents with a significant rise in MIC50 of beta-lactam antibiotics. There was no difference in the outcome of infections caused by penicillin-susceptible and -nonsuscetible S. pneumoniae. The only identifiable risk factor associated with PNSP infection was prior use of antibiotic within 3 weeks.

A prospective study in pediatric patients compared the BACTEC system, an automated blood culture system using Bactec Ped Plus/F broth media, with the conventional system using Brain Heart Infusion broth media. Each single blood sample drawn for culture from hospitalized children was evaluated by both systems simultaneously. Of 244 pairs of blood samples, 44 (18%) were positive for microorganisms. Of these isolates, 24 (55%) were detected by both systems, 10 (23%) were detected by the BACTEC system only, and 10 (23%) were detected by the conventional system only. The mean turn around time of the BACTEC system (0.56 +/- 0.34, range 0.08-1.55 days) was significantly shorter than that of the conventional system (3.36 +/- 2.72, range 1-7 days, p < 0.001). Seven isolates strongly suspected to be due to contaminants grew out after 5 days of incubation and were detected by the conventional system only. In this study the BACTEC system and the conventional system were equally effective in detecting microorganisms in the patients' blood samples even if antibiotic therapy had been previously administered. However, the results from the BACTEC system were available much sooner and less likely to be contaminants.

Sputum culture of patients at Siriraj Hospital, Bangkok was 49.84% positive for bacterial pathogens in 1994 and 40.95% in 1995. The average incidence of gram-negative rods was 3.11 fold more than the combination of gram-positive cocci and gram-negative cocci. The most common gram-negative rod was Pseudomonas aeruginosa, followed by either Klebsiella pneumoniae or Acinetobacter anitratus depending on year. The most common coccus was Staphylococcus aureus. From both years, the number of Haemophilus influenzae, Streptococcus pneumoniae, Burkholderia pseudomallei and Nocardia spp isolated were 122, 93, 13 and 11 strains respectively. For antimicrobial susceptibility, P. aeruginosa was sensitive to ceftazidime, imipenem, gentamicin, amikacin, netilmicin, ciprofloxacin (range 56-89%). S. aureus (MSSA) was sensitive to common used drugs. S. aureus (MRSA) was sensitive to co-trimoxazole, fosfomycin, vancomycin (range 57-100%) and resistant to most drugs.

Three cases with S. suis bacteremia and meningitis were reported. The first case was a 23-year-old butcher who was a regular drinker of alcohol for two years and developed streptococcal toxic-shock syndrome. The organism was transmitted to him through a minor cut in his right arm. The second cases was a 49-year-old female laborer who had been consuming locally produced alcohol for 20 years and developed fever and meningitis. Unfortunately, she succumbed in seven days despite intensive supportive and cefotaxime treatments. The third case was a 45-year-old regular alcoholic drinker and car painter who was seen at a private hospital due to contusion at his left lateral chest wall. However, fever and confusion due to meningitis was detected upon admission. Irreversible deafness developed within 48 hours of ceftriaxone therapy for meningitis. He finally recovered with deafness. S. suis was isolated from blood and cerebrospinal fluid cultures in all three cases though initially reported to be viridans group of streptococci.

Three hundred and four strains of beta-hemolytic streptococci were isolated from different patients at Siriraj Hospital during 1989-1990. Among these strains, 24.01% were group A, 23.03% were group B, 2.96% were group C, 29.61% were group D, 0.66% were group F, 6.25% were group G and 13.48% could not be grouped by using the Lancefield reference method. The distribution of each serogroup according to the types of clinical specimens was also studied. From pus, group A Streptococcus (44.8%) was the most frequent isolate. From vagina/cervix/urethra specimens, group B Streptococcus (47.95%) was the most frequent isolate. From urine, group D Streptococcus (82.5%) was the most frequent isolate. From blood, group B Streptococcus (43.33%) was the most frequent isolate. From throat/sputum specimens, only group A Streptococcus was isolated. There were some differences in susceptibility to 19 antimicrobial agents among various groups of streptococci. Resistance to penicillin was not found in groups A, B, C, F and G streptococci except for group D (91.1% resistance for enterococci and 33.3% resistance for non-enterococci) and nongroupable streptococci (12.2% resistance).

The epidemiology of Pseudomonas aeruginosa infection was studied in Siriraj Hospital. During April 1989-June 1990, P. aeruginosa 436 strains were isolated from clinical specimens of 260 patients, ie blood (19 strains), pus (192 strains), sputum (159 strains) and urine (66 strains). By using a combination of serogroups and pyocin types as epidemiological markers, it was found that there were 10 serogroups and 8 pyocin types which can be differentiated into 33 serogroup/pyocin types or patterns. The most common pattern was E 211111 (26.3%) followed by B 121614 (24.5%), G 373112 (13%) and L 888888 (7.1%), respectively.