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D A Dance

Publications and source records attributed to D A Dance.

At least 37 records · Page 2Linked to original sources
PubMed1997

Ribotype differences between clinical and environmental isolates of Burkholderia pseudomallei.

Burkholderia pseudomallei is isolated frequently from the soil in regions where the disease melioidosis occurs. However, recent surveys in Thailand have shown that the frequency of isolation of the organism from soil samples is not directly related to the incidence of melioidosis in an area. To determine whether strain populations of B. pseudomallei prevalent in soil are gentypically related to strains causing clinical disease, rRNA BamHI restriction fragment length polymorphisms (RFLP) of 139 soil environmental isolates and 228 human isolates were compared. Two groups of ribotype patterns were found. Group I comprised 37 different ribotype patterns which were characterised by five to eight hybridisation bands of 2.8- > 23 kb. All of these ribotypes were identified among the clinical isolates, and 18 of them were also found in 59 environmental isolates. Group II was represented by 12 ribotypes found only in environmental strains. These ribotype patterns comprised one to five bands in the size range 9- > 23 kb. All but one of the 73 isolates in this group grew on a minimal medium supplemented with L-arabinose. In contrast, only 3% of the 66 isolates from the environment with group I ribotype patterns could utilise this sugar as their sole energy source. These findings suggest that B. pseudomallei strains that utilise arabinose constitute a population that is genetically distinct from other environmental and clinical strains.

Arabinose↗
PubMed1996

A prospective clinical and bacteriologic study of inguinal buboes in Thai men.

One-hundred thirteen men (mean age, 23 years) who presented with inguinal buboes to a government-operated hospital for sexually transmitted diseases (STDs) in Bangkok were studied between February 1987 and February 1989. The median duration of preceding symptoms was 7 days (range, 1-62 days). The majority of patients (74; 65%) had received treatment previously; 31 (27%) were febrile, 13 (12%) had extrainguinal lymphadenopathy, and 31 (27%) had concurrent active genital ulcers. There was no history of genital ulceration in 66 (58%) of the patients. Pus was obtained from 51 of the 110 buboes aspirated for culture; 21 (41%) of these cultures yielded Haemophilus ducreyi, and 2 (3.9%) were positive for Chlamydia trachomatis on immunofluorescence microscopy. Saline (1 mL) was injected and reaspirated from the buboes of 35 of the other 59 patients; 3 buboes yielded H. ducreyi and 9 were positive for C. trachomatis. All cultures for other aerobic and anaerobic bacteria and viruses in intact buboes were negative. Syphilis serology was positive in only one case. Patients attending STD clinics in this region who have large, fluctuant, edematous inguinal buboes containing pus should receive presumptive treatment for chancroid. If there is no pus, then the bubo is more likely to be caused by lymphogranuloma venereum.

Adolescent↗
PubMed1996

Biochemical characteristics of clinical and environmental isolates of Burkholderia pseudomallei.

The biochemical characteristics of 213 isolates of Burkholderia pseudomallei from patients with melioidosis and 140 isolates from the soil in central and northeastern Thailand were compared. Whereas the biochemical profiles of all the clinical isolates were similar, all soil isolates from the central area and 25% of isolates from northeastern Thailand comprised a different phenotype. This was characterised by the ability to assimilate L-arabinose (100%), adonitol (100%), 5-keto-gluconate (90%) and D-xylose (84%), but failure to assimilate dulcitol (0%), erythritol (0%) and trehalose (10%). Compared with clinical isolates, these organisms had similar antibiotic susceptibility profiles and were also recognised by a specific polyclonal antibody against B. pseudomallei. As melioidosis is rare in central Thailand, but common in the northeast, this raises the possibility that this biochemical phenotype may be less virulent, or may even represent a different species.

Anti-Bacterial Agents↗
PubMed1995

Prognostic significance of quantitative bacteremia in septicemic melioidosis.

Pour-plate blood cultures were performed for 418 adult patients with suspected septicemic melioidosis in order to determine the relationship between quantitative bacterial counts in blood and mortality. Of 108 patients whose hemocultures yielded Burkholderia pseudomallei, 53% had < 10 cfu/mL and 24% had > 100 cfu/mL. High blood bacterial counts were more common than reported previously with regard to other gram-negative septicemias and were significantly associated with the development of hypotension (P = .008) and a fatal outcome (P = .0001). The overall mortality was 63% (95% CI, 53%-72%); however, counts of < or = 1 cfu/mL were associated with a mortality of 42% (95% CI, 28%-58%), compared with 96% (95% CI, 80%-100%) with counts of > 100 cfu/mL. Heavy bacteremia (> 50 cfu/mL) is common in septicemic melioidosis and is usually fatal.

Adolescent↗
PubMed1994

Ceftazidime vs. amoxicillin/clavulanate in the treatment of severe melioidosis.

An open, paired, randomized, controlled trial of high-dose parenteral ceftazidime (120 mg/[kg.d]) vs. amoxicillin/clavulanate (160 mg/[kg.d]) for the treatment of severe melioidosis was conducted in Ubon Ratchatani in northeastern Thailand. Of 379 patients enrolled in the study, 212 (56%) had culture-proven melioidosis; 106 patients were in each treatment group. The overall mortality rate (47%) was similar for both treatment groups. However, 4 of 75 surviving patients in the ceftazidime group compared with 16 of 69 surviving patients in the amoxicillin/clavulanate group were switched to the alternate regimen because of an unsatisfactory clinical response after > or = 72 hours of treatment (P = .004). The overall therapeutic failure rate (i.e., treatment failure or death due to uncontrolled melioidosis) was significantly higher for the amoxicillin/clavulanate group than for the ceftazidime group (P = .02). Clinical and bacteriologic responses for successfully treated patients were similar in both groups, and both treatments were well tolerated. Parenteral amoxicillin/clavulanate is a safe and effective initial treatment, but parenteral ceftazidime remains the treatment of choice for severe melioidosis.

Adolescent↗
PubMed1994

The epidemiology of melioidosis in Ubon Ratchatani, northeast Thailand.

BACKGROUND: Melioidosis, or infection with Pseudomonas pseudomallei is an important cause of morbidity and mortality in South East Asia and Northern Australia. The epidemiology of melioidosis in Ubon Ratchatani, Northeast Thailand was studied over a 5-year period from 1987 to 1991. METHODS: Rates and, when possible, the risks of developing melioidosis were calculated. The numerator was the number of culture-proven cases of melioidosis seen in the 1000-bed referral hospital of the province. The denominators were obtained from the population census, a survey of Health, Welfare and Use of Traditional Medicine, and the North Eastern Meterological Centre, Thailand. RESULTS: The average incidence of human melioidosis was 4.4 (95% confidence interval [CI]: 3.8-5.0) per 100,000. The disease affected all ages with the highest incidence in 40-60 years olds. Melioidosis was 1.4 (95% CI: 0.4-5.3) times more common in males than females. The disease showed a significant seasonal variation in incidence, and a strong linear correlation with rainfall (r = 0.7, 95% CI: 0.5-0.9) Adults exposed to soil and water in their work (most were rice farmers) had an increased risk of melioidosis (in the 40-59 year age group, relative risk = 4.1, 95% CI: 2.4-6.9). Most adult patients had an underlying disease (mainly diabetes mellitus) predisposing them to this infection. CONCLUSION: Melioidosis may result from either acute exposure to the organism in the soil and water, or 're-activation' of an asymptomatic childhood infection (by an unidentified possibly infective seasonal cofactor). The results from this analysis are consistent with both hypotheses. Further epidemiological studies are needed to identify risk factors so that optimal strategies for control of melioidosis may be developed.

Adolescent↗
PubMed1994

Detection of Pseudomonas pseudomallei antigen in urine for the diagnosis of melioidosis.

An enzyme-linked immunosorbent assay using a fluorescein isothiocyanate (FITC)-anti-FITC amplification system, has been developed to detect Pseudomonas pseudomallei antigen in urine. The assay was evaluated in 135 patients with acute melioidosis, 194 hospitalized patients with other disorders, and 40 healthy controls. Antigen was detected in the urine of 123 (91%) patients with melioidosis. Urinary antigen was found in 85 (96%) of 89 patients with septicemic melioidosis, all six patients with P. pseudomallei urinary tract infection, and 32 (80%) of 40 patients with other localized infections. Antigen was not detected in the urine of 40 healthy individuals, but the urine of 16 (8%) of 194 hospitalized patients with diagnoses other than melioidosis gave a positive result. Of the false-positive results, 13 of 16 were associated with bacteriuria > or = 10(4) colony-forming units/ml. At a cutoff titer of 1:10, the sensitivity and specificity of the test were 81% and 96%, respectively. Enzyme immunoassay detection of urinary antigen is a valuable and rapid laboratory test for the early diagnosis of acute melioidosis.

Acute Disease↗
PubMed1993

Serology and carriage of Pseudomonas pseudomallei: a prospective study in 1000 hospitalized children in northeast Thailand.

Throat swab cultures and indirect hemagglutination assay (IHA) for Pseudomonas pseudomallei were done in 1000 randomly selected children at a large hospital in northeast Thailand. During 18 months, 17 children with melioidosis were admitted (0.46% of pediatric admissions excluding neonates born in the hospital). Throat swab was positive for P. pseudomallei in 8 of these but in none of 1000 control children. IHA seroprevalence rose at a conversion rate of 24% per year, from 12% in those 1-6 months old to a plateau at approximately 80% after age 4 years. No control child < 4 had an IHA titer > 1:160. The median titer in children with melioidosis was 1:80 (range, negative [in3]-1:5120). Specificity of IHA declined with age, but high titers (> or = 1:640) remained diagnostically useful. Thus, throat carriage of P. pseudomallei indicates active melioidosis. There is no evidence for an asymptomatic carrier state in children. Environmental exposure to P. pseudomallei in endemic areas begins when the child becomes mobile.

Adolescent↗
PubMed1993

Relationships among Pseudomonas pseudomallei isolates from patients with recurrent melioidosis.

Patients with melioidosis may present with recurrent infections after clinical resolution of their primary illness. Because there has been no satisfactory typing scheme for Pseudomonas pseudomallei, recrudescence could not be distinguished from reinfection. We determined the strain identity of primary and relapse isolates of P. pseudomallei from 25 patients with culture-proven melioidosis to answer whether secondary infections were due to the initial infecting strain or to the acquisition of a new strain. Fifty-four isolates were compared by the patterns of BamHI restriction digests produced after hybridization with a cDNA copy of Escherichia coli rRNA. Twenty-three patients had primary and relapse isolates with identical or highly similar ribotype patterns. The patterns of isolates from two patients were different; the primary and relapse isolates differed by a single fragment for one, and the other had identical primary and first-relapse isolates while the second-relapse isolate was markedly different. The results indicated that recurrent infection probably resulted from endogenous relapse in most of the melioidosis patients studied, although reinfection from an exogenous source was also possible in two cases.

Bacterial Typing Techniques↗
PubMed1993

Relapse in melioidosis: incidence and risk factors.

From 1986 to 1991, 602 patients with melioidosis were seen in Sappasitprasong Hospital, Ubon Ratchatani, Thailand. The in-hospital mortality was 42%. Of 118 adult patients followed long-term, 27 (23%) had culture-proven relapses of melioidosis (3 relapsed twice), a relapse rate of 15% (95% confidence interval [CI], 11-22) per year. The median time from discharge to relapse was 21 weeks (range, 1-290). In 44% of patients, relapses included septicemia, and 27% died. Patients with severe disease (multiple foci of infection or septicemia) relapsed 4.7 times (95% CI, 1.6-14.1) more frequently than patients with localized melioidosis. Underlying disease was not a risk factor, but initial parenteral treatment with ceftazidime reduced the risk of relapse 2-fold (95% CI, 1.1-3.4). Relapses were 3.3 (95% CI, 1.4-9.0) times more frequent following short-course (< or = 8 weeks) oral coamoxiclav than after the oral combination regimen of chloramphenicol, doxycycline, and cotrimoxazole. Longer oral treatment with either reduced relapse 1.6-fold (95% CI, 1.2-1.9). The optimum choice and duration of antibiotic treatment to prevent relapse in melioidosis remain to be determined.

Adolescent↗
PubMed1992

An outbreak of melioidosis in imported primates in Britain.

An outbreak of melioidosis, a bacterial infection caused by Pseudomonas pseudomallei, was identified in a batch of feral cynomolgus monkeys (Macaca fascicularis) imported to Britain from the Philippines. Thirteen confirmed or possible cases occurred among a batch of 50 animals. Subsequent investigations revealed that the infection was uncommon among imported primates from a variety of sources, although three other cases were identified in monkeys imported from Indonesia. The majority of the affected monkeys had splenic abscesses, and hepatic abscesses and infections of the soft tissues and skin were also frequently observed. Most of the infected animals had no clinical signs despite extensive abscesses, and the presence of infection was only suspected when they were shown to have serum antibodies to P pseudomallei by an enzyme-linked immunosorbent assay. Although there was no evidence of cross infection of other animals or human handlers, this outbreak is a reminder of the dangers of working with wild-caught primates and the potential for the establishment of environmental foci of melioidosis.

Abscess↗
PubMed1992

Homogeneity of lipopolysaccharide antigens in Pseudomonas pseudomallei.

An antiserum raised against a single strain of Pseudomonas pseudomallei reacted equally in a whole cell agglutination test, an indirect haemagglutination (IHA) test and an ELISA with a panel of 12 strains of the species which had been isolated from human beings and animals in various parts of the Far East and Australia between 1923 and 1990. Absorption of the serum with either of two strains removed all reactivity of the serum with other strains. Phenol-water extracted lipopolysaccharide (LPS) from a single strain blocked the reactivity of the serum with red cells sensitised with crude extracts of any of the panel of strains, thereby suggesting that the 'common' antigen was LPS. This antigen was not detected in other Pseudomonas species with the exception of Pseudomonas mallei. Protease K-digested extracts of the 12 strains gave highly similar silver-stained LPS banding patterns in gel electrophoresis. Furthermore, immunoblots of LPS with either rabbit or a patient's serum showed identical ladder profiles for each strain. The results suggest that the LPS antigen is highly conserved throughout P. pseudomallei and that this antigen is detected by the IHA test.

Agglutination Tests↗
PubMed1992

Pseudomonas pseudomallei liver abscesses: a clinical, laboratory, and ultrasonographic study.

Ultrasonography revealed evidence of liver abscess in 126 patients who were admitted to one hospital in northeastern Thailand over a 3-year period. There were 50 cases for which a pyogenic bacterial etiology was confirmed; 34 cases (group 1) were caused by Pseudomonas pseudomallei (nine patients died) and 16 cases (group 2) were caused by other bacteria (two patients died). Melioidosis was associated with anemia and underlying diabetes or renal disease; right-upper-quadrant pain and jaundice were more common in group 2 (P less than .05). Blood cultures were positive for bacteria in 68% of group 1 and 50% of group 2. Chest radiographs revealed abnormalities in 17 of 30 group 1 patients and 6 of 12 group 2 patients. The radiographic appearances of a blood-borne pneumonia suggested melioidosis. The serum indirect hemagglutination assay for antibodies to P. pseudomallei was of limited value in differentiating the two types of abscesses. Multiple hypoechoic areas on ultrasonography were significantly associated with melioidosis (P less than .01); associated splenic abscess occurred in 19 group 1 patients but only one group 2 patient (2-107, 95% confidence interval; odds ratio, 19). In an area where P. pseudomallei is endemic, these characteristic ultrasonographic findings should prompt immediate treatment for melioidosis.

Adolescent↗