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Stephen Chambers

Publications and source records attributed to Stephen Chambers.

11 recordsLinked to original sources
PubMed2006

Dimethylthetin treatment causes diffuse alveolar lung damage: a pilot study in a sheep model of Continuous Ambulatory Peritoneal Dialysis (CAPD).

Total plasma homocysteine (Hcy) concentration correlates with risk of vascular disease. Over 80% of chronic renal failure patients have elevated plasma Hcy and a 10-20 times higher incidence of vascular disease. Glycine betaine lowers plasma Hcy through methylation catalysed by betaine-homocysteine methyltransferase (BHMT). Dimethylthetin (DMT), a synthetic glycine betaine analogue, is a more effective BHMT substrate. DMT is therefore a potential therapeutic agent for reducing plasma Hcy in humans and may be particularly useful in renal failure patients receiving dialysis because of chronic betaine depletion as a result of treatment. We aimed to determine whether the addition of DMT to dialysis fluid lowered plasma Hcy concentrations in a Continuous Ambulatory Peritoneal Dialysis sheep model using animals that were either in acute renal failure (n=3) or had normal renal function (n=1). Sub-acute exposure to DMT was toxic to all four animals, which died with total lung consolidation and collapse and Diffuse Alveolar Damage within 48 h of beginning treatment. Adverse side effects were observed after 4-8 doses. DMT was not detected in pre-dialysis plasma samples and the final concentration at death was 0.5-7.8 mmol/L, depending on the number of doses each animal was exposed to. Abnormalities were not observed in animals supplied standard dialysis fluid, or fluid with added glycine betaine. Toxicity associated with DMT treatment raises concerns for its use in further studies. However, sub-acute administration of DMT to sheep may provide a useful model of acute alveolar damage.

Animals↗
PubMed2006

Māori have a much higher incidence of community-acquired pneumonia and pneumococcal pneumonia than non-Māori: findings from two New Zealand hospitals.

To determine the incidence rates of community-acquired pneumonia and pneumococcal pneumonia requiring hospitalisation among Maori and non-Maori, an observational study was conducted in Christchurch and Hamilton. Self-reported data were collected using an interviewer-administered questionnaire. Routine clinical, radiological, and microbiological techniques were used apart from the BinaxNow pneumococcal antigen test for diagnosis of this infection. Census data was used to determine the denominator for statistical analyses. The pneumonia rate overall was 3.03 times higher among Maori than non-Maori (p<0.001). Differences were significant for each 10-year age group from age 45-74 years (p<0.05). The rate of pneumococcal pneumonia was 3.23 fold higher for Maori than non-Maori (p<0.001), but it did not reach statistical significance in the age-related comparisons. These ethnic disparities are of major concern, and policy planners should consider further interventions to improve the efficacy of current anti-smoking campaigns and to undertake studies of conjugate pneumococcal vaccines for Maori.

Adolescent↗
PubMed2006

Cutaneous larva migrans (hookworm) acquired in Christchurch, New Zealand.

A case of cutaneous larva migrans is presented. The patient acquired the parasite in a suburban Christchurch property. A biopsy confirmed the clinical diagnosis. Cutaneous larva migrans is common in returned travellers from the tropics. It is rare in New Zealand, however. Presumably there were very specific, favourable local factors to allow maturation and transmission of the larva in this case.

Aged, 80 and over↗
PubMed2005

Increased rates of trimethoprim resistance in uncomplicated urinary tract infection: cause for concern?

AIMS: To assess changes in trimethoprim resistance over 2 years in bacteria causing uncomplicated urinary tract infections (UTIs) presenting to a representative group of general practitioners (GPs) in Christchurch. METHODS: Seventy-six randomly selected GPs in Christchurch (the Christchurch Sentinel network) participated in the study. Using the same methodology as in the previously reported 2000 collection, midstream urine (MSU) samples were prospectively collected for standard microbiological analysis on all women between the ages of 16 and 50 years presenting with symptoms of dysuria and frequency and who had positive dipstick testing for either nitrites, leucocytes, or both. MSUs were submitted for bacterial colony counts and resistance testing of isolates present in numbers >105 cfu/ml of urine. RESULTS: 216 dipstick positive specimens were collected in the survey period; 105 of these fulfilled criteria for significant bacteriuria. Trimethoprim resistance was found in 16 (15.2%) overall, with a resistance rate for Escherichia coli (E. coli) to trimethoprim of 17.7%. When compared to the proportions of organisms resistant in the 2000 study, there were apparent but non significant increases in the total resistance among pathogens (+6.7%) and E. coli resistance (+5.8%). Rates of antibiotic resistance of all organisms to nitrofurantoin (2.9%) and norfloxacin (0.95%) remain low. There was a statistically significant increase in resistance among all women presenting with symptoms and a positive dipstick test (+5.3%; 95% CI: 1.5%-9.1%). For a woman in this age group presenting with symptoms of urinary tract infection and a positive dipstick test, we estimate that her probability of having a trimethoprim-resistant organism in 2002 was 7.4% compared with 2.7% in 2000. CONCLUSION: Trimethoprim resistance of E. coli causing uncomplicated UTI appears to be rising in Christchurch. This may reflect the promotion and extensive use of this agent as first-line treatment. Whilst these data indicate that trimethoprim remains a reasonable first-line empiric treatment in this condition, this may change if trimethoprim resistance continues to rise. The apparent increase over a relatively short period (2-3 years) demonstrates the importance of regular surveillance. A third study is required to confirm whether this is a significant trend.

Adolescent↗
PubMed2005

Response to antibiotics of women with symptoms of urinary tract infection but negative dipstick urine test results: double blind randomised controlled trial.

OBJECTIVE: To assess the effectiveness of antibiotic treatment of women with symptoms of urinary tract infection but negative urine dipstick testing. DESIGN: Prospective, double blind, randomised, placebo controlled trial. SETTING: Primary care, among a randomly selected group of general practitioners in Christchurch, New Zealand. PARTICIPANTS: 59 women aged 16-50 years presenting with a history of dysuria and frequency in whom a dipstick test of midstream urine was negative for both nitrites and leucocytes. Participants with complicated urinary tract infection were excluded. INTERVENTION: Trimethoprim 300 mg daily for three days or placebo. MAIN OUTCOME MEASURES: Self reported diary of symptoms for seven days, recording the presence or absence of individual symptoms each day, followed by a structured telephone questionnaire after seven days. The main clinical outcome was resolution of dysuria at three and seven days and median time to resolution. Secondary outcomes were resolution of other symptoms. RESULTS: The median time for resolution of dysuria was three days for trimethoprim compared with five days for placebo (P = 0.002). At day 3, five (24%) of patients in the treatment group had ongoing dysuria compared with 20 (74%) in the placebo group (P = 0.005). This difference persisted until day 7: two patients (10%) in the treatment group v 11 (41%) in the placebo group; P = 0.02). The number needed to treat was 4. The median duration of constitutional symptoms (feverishness, shivers) was reduced by four days. CONCLUSIONS: Although a negative dipstick test for leucocytes and nitrites accurately predicted absence of infection when standard microbiological definitions were used (negative predictive value 92%), it did not predict response to antibiotic treatment. Three days' treatment with trimethoprim significantly reduced dysuria in women whose urine dipstick test was negative. These results support the practice of empirical antibiotic use guided by symptoms. Balancing the competing interests of symptom relief and the minimisation of antibiotic use remains a dilemma-further research is needed to determine clinical predictors of response to antibiotics.

Adolescent↗
PubMed2004

Randomised controlled trial of intravenous antibiotic treatment for cellulitis at home compared with hospital.

OBJECTIVES: To compare the efficacy, safety, and acceptability of treatment with intravenous antibiotics for cellulitis at home and in hospital. DESIGN: Prospective randomised controlled trial. SETTING: Christchurch, New Zealand. PARTICIPANTS: 200 patients presenting or referred to the only emergency department in Christchurch who were thought to require intravenous antibiotic treatment for cellulitis and who did not have any contraindications to home care were randomly assigned to receive treatment either at home or in hospital. MAIN OUTCOME MEASURES: Days to no advancement of cellulitis was the primary outcome measure. Days on intravenous and oral antibiotics, days in hospital or in the home care programme, complications, degree of functioning and pain, and satisfaction with site of care were also recorded. RESULTS: The two treatment groups did not differ significantly for the primary outcome of days to no advancement of cellulitis, with a mean of 1.50 days (SD 0.11) for the group receiving treatment at home and 1.49 days (SD 0.10) for the group receiving treatment in hospital (mean difference 0.01 days, 95% confidence interval -0.3 to 0.28). None of the other outcome measures differed significantly except for patients' satisfaction, which was greater in patients treated at home. CONCLUSIONS: Treatment of cellulitis requiring intravenous antibiotics can be safely delivered at home. Patients prefer home treatment, but in this study only about one third of patients presenting at hospital for intravenous treatment of cellulitis were considered suitable for home treatment.

Adolescent↗
PubMed2004

AIDS in New Zealand.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Home intravenous antimicrobial service--twelve months experience in Christchurch.

AIM: To review the clinical practice and complications of the home intravenous antimicrobial service at Christchurch Hospital after twelve months of full operation. METHODS: Clinical and microbiological diagnoses, antimicrobial therapy, and complications of home intravenous antimicrobial therapy were entered prospectively on an Excel data base. RESULTS: Of the 153 patients, 113 (74%) suffered from skin, soft tissue or bone and joint disease. A bacteriological diagnosis was made in 108 patients (71%). 119 patients were treated with the narrow spectrum agents--penicillin 20 (13%), flucloxacillin 55 (36%) and cephazolin 44 (29%). Ceftriaxone was used for treatment in fifteen (10%) patients. Peripherally inserted central catheters (PICC's) were used in 129 patients, midlines fifteen, peripheral angiocaths in eight, and a Portacath in one. An elastomeric infusion device was used in 80 patients and an infusion pump in 34. Complications developed in 31 (20%) patients including three infections and one jugular vein thrombosis. Fifteen patients (10%) were readmitted within one month of discharge. CONCLUSIONS: The home intravenous therapy programme successfully used first line narrow spectrum agents initiated in hospital with avoidance of unnecessary broad spectrum agents. Complication rates were acceptable and likely to improve with experience in patient selection and provision of support services.

Adolescent↗