Search PubMed⌕ Search

Biomedical subjects

N Aswapokee

Publications and source records attributed to N Aswapokee.

At least 19 recordsLinked to original sources
PubMed2002

Antimicrobial resistance among respiratory pathogens collected in Thailand during 1999-2000.

A multi-center surveillance study was conducted in Thailand during 1999-2000 to determine antimicrobial susceptibilities among the respiratory pathogens Streptococcus pneumoniae (n = 206), Haemophilus influenzae (n = 305), and Moraxella catarrhalis (n = 39). Of the S. pneumoniae isolates collected, 33.5% were penicillin-susceptible, 27.2% intermediate and 39.3% resistant. Expectedly, resistance rates to beta-lactams were higher among penicillin-resistant (ceftriaxone, 14.8%; amoxicillin-clavulanate, 42.0%; cefuroxime, 100%) than penicillin-susceptible (ceftriaxone, 0%; amoxicillin-clavulanate, 0%; cefuroxime, 0%) isolates. Likewise, azithromycin and clarithromycin resistances were 4.3% and 5.8% among penicillin-susceptible isolates, and 77.8% and 95.1% among penicillin-resistant isolates. All S. pneumoniae remained susceptible to vancomycin and 99.5% were susceptible to levofloxacin. Multidrug resistance (resistance to >3 antimicrobial classes) was present in 25.2% of pneumococcal isolates (n = 52), with resistance to azithromycin, penicillin and trimethoprim-sulfamethoxazole the most common phenotype (40/52 isolates; 77.0%). Among the isolates of H. influenzae, the prevalence of beta-lactamase production was 45.2%. All isolates of H. influenzae were susceptible to amoxicillin-clavulanate, azithromycin, ceftriaxone, cefuroxime and levofloxacin while 49.5% were resistant to trimethoprim-sulfamethoxazole. All 39 isolates of M. catarrhalis produced beta-lactamase. Azithromycin (MIC90, < or = 0.03 microg/ml) and levofloxacin (MIC90, 0.03 microg/ml) were the most active agents tested against M. catarrhalis. The results of this study may serve as a baseline for future studies to monitor antimicrobial susceptibilities among respiratory pathogens in Thailand.

Anti-Bacterial Agents↗
PubMed2001

Carriage of antibiotic-resistant pneumococci among Asian children: a multinational surveillance by the Asian Network for Surveillance of Resistant Pathogens (ANSORP).

To investigate the nasal carriage of antibiotic-resistant pneumococci by children, anterior nasal swabs were done for 4963 children <5 years old in 11 countries in Asia and the Middle East. In total, 1105 pneumococci isolates (carriage rate, 22.3%) were collected, 35.8% of which were found to be nonsusceptible to penicillin. Prevalence of penicillin nonsusceptibility was highest in Taiwan (91.3%), followed by Korea (85.8%), Sri Lanka (76.5%), and Vietnam (70.4%). Penicillin resistance was related to residence in urban areas, enrollment in day care, and a history of otitis media. The most common serogroups were 6 (21.5%), 23 (16.5%), and 19 (15.7%). The most common clone, as assessed by pulsed-field gel electrophoresis, was identical to the Spanish 23F clone and to strains of invasive isolates from adult patients. Data in this study documented the high rate of penicillin or multidrug resistance among isolates of pneumococci carried nasally in children in Asia and the Middle East and showed that this is due to the spread of a few predominant clones in the region.

Anti-Bacterial Agents↗
PubMed1999

Spread of drug-resistant Streptococcus pneumoniae in Asian countries: Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study.

Antimicrobial susceptibility of 996 isolates of Streptococcus pneumoniae from clinical specimens was investigated in 11 Asian countries from September 1996 to June 1997. Korea had the greatest frequency of nonsusceptible strains to penicillin with 79.7%, followed by Japan (65.3%), Vietnam (60.8%), Thailand (57.9%), Sri Lanka (41.2%), Taiwan (38.7%), Singapore (23.1%), Indonesia (21.0%), China (9.8%), Malaysia (9.0%), and India (3.8%). Serotypes 23F and 19F were the most common. Pulsed-field gel electrophoresis (PFGE) of 154 isolates from Asian countries showed several major PFGE patterns. The serotype 23F Spanish clone shared the same PFGE pattern with strains from Korea, Japan, Singapore, Taiwan, Thailand, and Malaysia. Fingerprinting analysis of pbp1a, pbp2x, and pbp2b genes of 12 strains from six countries also showed identical fingerprints of penicillin-binding protein genes in most strains. These data suggest the possible introduction and spread of international epidemic clones into Asian countries and the increasing problems of pneumococcal drug resistance in Asian countries for the first time.

Aminoacyltransferases↗
PubMed1999

Efficacy and safety of twice daily administration of cefpirome in the empiric treatment of sepsis.

Cefpirome is a fourth-generation cephalosporin with good activity against both gram-positive and gram-negative bacteria. A multicentre trial was performed to study the efficacy and safety of cefpirome 2 g twice daily in the treatment of sepsis. Sixty-three cases were recruited from 10 hospitals from April 1996 to January 1998. Fifty seven cases could be evaluated according to the protocol. The APACHE II score was used to measure severity of illness, with 46.9 per cent of patients having APACHE II score more than 10 and two patients more than 20; both were cured. The most common pathogens were gram-negative bacteria with E. coli predominating 16/40 (40.0%), followed by Klebsiella 8/40 (20.0%). The overall clinical success rates were 54 out of 57 patients (94.7%). In patients with positive blood culture, the clinical cures were achieved for 20/22 (90.9%). Cefpirome showed good efficacy and safety in the empirical treatment of suspected bacteremia or sepsis.

Adolescent↗
PubMed1993

Empirical antibiotic therapy in febrile neutropenic patients with single-daily dose amikacin plus ceftriaxone.

Hematologic malignancies and cancer patients who become neutropenic as a result of disease or myelosuppressive cytotoxic therapy are at a high risk of developing life-threatening infections, and hence empirical antibiotic therapy is administered promptly. We investigated once daily regimen of amikacin, for dose-dependent bactericidal activity and post-antibiotic effects, plus ceftriaxone, with a long-half life to maximise time-dependent bactericidal activity. Microbiologically proven septicemia were 11 out of 49 febrile episodes (22.5%) and 10 (91%) of these were due to gram-negative bacilli, mostly Enterobacteriaceae. The overall success of the regimen was 63.3 per cent of patients, with no significant toxicity. In conclusion, our findings suggest that once-daily administration of amikacin plus ceftriaxone in the initial treatment of febrile episodes in neutropenic patients produces satisfactory results and more cost-effective compared with other antibiotic regimens requiring 3-4 doses a day.

Adolescent↗
PubMed1992

The failure of a preprinted order form to alter physicians' antimicrobial prescribing pattern.

Use of antimicrobial agents is highly effective in reduction of morbidity and mortality due to infectious disease. There is, however, evidence that the use of such agents is frequently inappropriate worldwide. Several methods were tried to rationalize the use, and, among these, the preprinted order form (P.O.F.) offered the simplest and most efficient way. We studied the use of the P.O.F. in Siriraj Hospital, Bangkok Thailand, where there was overuse of antimicrobial agents using a historical-controlled intervention study. In period I (no P.O.F.), the antimicrobial overuse was 35 per cent, and this was not reduced by using the P.O.F. in period II (32%), which was one year apart. There was no difference in overuse after adjustment for differences in base-line characteristics which were thought to affect antimicrobial prescriptions i.e. physicians' workload, physicians' knowledge and the method of diagnosis of infectious disease. Reasons for failure of the P.O.F. in unclear. Misdiagnosis was unlikely since the correct diagnosis as revised by attending physicians and specialists was as high as 83 per cent. The fear of malpractice suits was also not the reason because defensive medicine is not a problem in Thailand. The nature of the diseases, which lower the threshold to treat, the clinical immaturity and other unknown factors were thought to play a part in deviation from responsibility to perform according to written-justification.

Adult↗
PubMed1992

In vitro antimicrobial activity of cefodizime, a third generation cephalosporin.

Cefodizime is one of the new broad-spectrum cephalosporins. It is an aminothiazolyl iminomethoxy cephalosporin which is metabolically stable and has a prolonged serum half life. Cefodizime was primarily active against gram-negative bacilli and at the concentration of 0.5 mg/L, it inhibited 90 per cent of Enterobacteriaceae. P. mirabilis was the most susceptible species tested (MIC90 of 0.02 mg/L). E.coli, K.pneumoniae, Salmonella spp., Shigella spp. and M. morganii were also very sensitive to cefodizime, with the MIC90 of 0.25-0.5 mg/L. Cefodizime, however, was not active against most gram-negative bacilli possessing Type I beta-lactamases of Richmond and Sykes, namely, Enterobacter spp., P. aeruginosa and A. anitratus (MIC90 of > 128 mg/L). Among gram-positive bacteria, only S.pyogenes was highly susceptible (MIC90 of 0.05 mg/L), while S. aureus (methicillin-sensitive) was moderately susceptible and Enterococcus spp. was resistant. Cefodizime appeared to be bactericidal and was not affected by serum. High inoculum (10(7) cfu/ml) of K.pneumoniae and Enterobacter spp. resulted in increase of the MIC of cefodizime. This study shows that local bacterial isolates in a university hospital in Bangkok, Thailand were not different in susceptibility pattern from those reported in developed countries. The in vitro activity of cefodizime as a third generation cephalosporin, with its good pharmacokinetic property, and the property of the agent as a biological response modifier, should prove that this is a promising new agent in treating serious infections especially in immunosuppressed hosts.

Cefotaxime↗
PubMed1991

Leukocyte and neutrophil counts in differential diagnosis of acute febrile conditions.

Leukocyte and neutrophil counts are two of the commonest laboratory tests used in clinical medicine. The usefulness of the tests is still controversial. It has been found that the tests were useful to a limited extent. We performed leukocyte and neutrophil counts in patients manifesting acute febrile illness, to identify the best cut-off point in differential diagnosis of underlying disorders causing such conditions. Patients were enrolled randomly on the basis of acute febrile illness. Those who suffered from diseases affecting myeloproliferative system were excluded. Leukocyte and neutrophil counts were performed by the standard method. Diagnosis of target organ disorder was obtained from the house staff's final diagnosis. Both laboratory and clinical performance were assessed in double blind fashion. Patients were divided into 2 groups. Group 1 consisted of 47 patients with acute bacterial infections and group 2 consisted of 53 cases with acute febrile conditions caused by diverse, non-bacterial disease. Various cut off points ranging from 5,000-25,000/mm3 and 10-100 per cent were used for leukocyte and neutrophil counts. Sensitivity, specificity and Youden index for each cut off point were determined. Receiver operating characteristic (ROC) curves were constructed. It was found that sensitivity and specificity for each cut off point for both leukocyte and neutrophil counts displayed perfect trade-offs and the Youden indices were similar. The ROC curves for both counts were depicted as a 45-degree lines of non-discrimination. Leukocyte and neutrophil counts were proved to be non-discriminate of acute febrile conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Survival of Pseudomonas pseudomallei in human phagocytes.

Pseudomonas pseudomallei causes the disease melioidosis, with protean manifestations, protracted clinical course and unpredictable response to antimicrobial treatment. Intracellular location of the organism is suspected to be the cause of these properties. This study was undertaken to examine the intracellular growth of this bacterium. Intracellular growth and survival was assessed at different time intervals, by Gram's stain and electronmicroscopic examination. During the first 5 h, the numbers of P. pseudomallei within phagocytes did not change significantly. By 18-21 h, gram-stained preparations revealed that P. pseudomallei cells completely filled the phagocytes and electronmicroscopy showed evidence of binary fission. During that time the number of cfu of P. pseudomallei growing simultaneously in vitro increased by log10 2-3. The phagocytes remained viable throughout the observation period and retained their capacity to produce an oxidative burst for the first hour of incubation. The ability of P. pseudomallei to survive and multiply in phagocytes shows that it is a facultative intracellular bacterium. This finding is relevant to the selection of antimicrobial regimens, and the management of the disease.

Colony Count, Microbial↗
PubMed1990

Ciprofloxacin in severe infections.

Ciprofloxacin is the most potent post-marketing fluoroquinolone. In vitro activity and pharmacokinetic properties of this agent, together with clinical trials of the drug may be very promising in the treatment of severe infections, especially when the bacteria involved are resistant to other conventional agents. We performed an open clinical trial of this agent in hospitalized patients with severe infections in a university hospital in Bangkok, Thailand. A total of 25 patients were enrolled on the basis of clinical diagnosis of severe bacterial infections. Six of these patients were dropouts (3 of which proved to be non-bacterial infections, 2 patients each had only anaerobic infection and nocardiosis. One suffered from a severe psychotic attack). The remaining 19 patients were evaluated. There were 12 males and 7 females, the age ranged from 13 to 77 years old (43.2 +/- 20.1). Most had severe underlying illnesses (17 out of 19). There were 23 infections in 19 patients. Septicemia was the most common infection treated. Other infections included complicated urinary infection, upper respiratory tract infection, skin/skin structure infection. P. aeruginosa was the most common pathogen infected. Other organisms were E.coli, Enterobacter, P.mirabilis, S.aureus, A.antitratus and mycobacterium. Ciprofloxacin was given as an initial 100 mg twice daily as intravenous infusion, and this was switched to an oral form of 500 mg b.i.d./at approximately day 4 to day 6. The overall cure rate was 68 per cent. There were 2 improvements, 2 relapses/reinfections and one failure. Toxic effect included one psychotic attack necessitating discontinuation of the drug. Other adverse drug reactions were mild and transient. These included elevation of transaminase and LDH.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

In vitro activities of antimicrobial combination against Pseudomonas pseudomallei.

P pseudomallei infection was treated empirically with an antimicrobial combination without hard evidence of a more favorable outcome over single drug regimens. The so-called "conventional' agents, namely kanamycin (K), chloramphenicol (C), doxycycline (D) and sulfamethoxazole/trimethoprim (SMZ/TMP) are often combined. We determined the effects of the combination of these agents by standard time-kill curve. Six combinations were tested, i.e. K and C, K and D, K and SMZ/TMP, C and D, C and SMZ/TMP, and lastly, D and SMZ/TMP. Three recent clinical isolates of P. pseudomallei were used. The antimicrobial concentration in the combination selected was one-fourth of the minimal inhibiting concentration (MIC). Colony counts were performed at times 0, 2, 4, 6 and 24 hours. The results were interpreted using standard definition, as synergistic, additive and antagonistic effects. It was found that at time 0 to 6 hours, all of the combinations only acted additively. At 24 hours, however, there were 3 effects observed. These were (1) synergistic effects for K and D, and C and D; (2) additive effect for K and C, K and SMZ/TMP, and D and SMZ/TMP; and (3) antagonistic effect for C and SMZ/TMP. None of the combinations showed rapid killing rates. The results, although subjected to precautious extrapolation of in vitro to in vivo situations, suggested that the combined regimens of "conventional' drugs often acted additively, and none of these combinations offered fast killing.

Anti-Bacterial Agents↗
PubMed1987

Viral infections in beta-thalassemia/hemoglobin E patients.

One hundred ten patients with beta-thal/Hb E disease and 60 normal controls matched for age and socioeconomic status were followed for 1.5 years. They were examined clinically, and blood and plasma were studied for Coxsackie B viruses and others. The findings suggest that the patients are more susceptible to Coxsackie B virus but not to rubella, herpes simplex, cytomegalovirus, adenovirus, and M. pneumoniae. In contrast to bacterial infections, splenectomized patients did not show evidence of increased viral infections.

Antibodies, Viral↗
PubMed1986

Persistent bacterial endocarditis caused by three isolates of satellite streptococci.

Three isolates of satellite streptococci were cultivated from the blood of a patient affected persistent bacterial endocarditis. They had distinguishable ultrastructural abnormalities. Their cell wall architecture changed from a fuzzy coat (first isolate) to a thick electron transparent layer covered with a rough fuzzy coat (second isolate), and to electron dense globular material which detached from the wall in small patches (third isolate). The antibiotics probably played an important role in changing their architecture. These three isolates were probably derived from the same strain, since they had common biochemical characteristics and they were isolated from the same patient during the course of his endocarditis.

Adult↗