Selenium status and allergic disease in a cohort of New Zealand children.

BACKGROUND: New Zealand has one of the highest rates of asthma and atopy. Selenium has been implicated in the aetiology of asthma, and associations between low selenium status and asthma in New Zealand children have been reported. OBJECTIVE: The aim was to investigate the association between selenium status and allergic disease in a birth cohort of New Zealand children. METHODS: The New Zealand Asthma and Allergy Cohort Study is a prospective birth cohort in Wellington and Christchurch, involving 1105 infants born 1997-2001. During the 6-year assessment (n = 635), associations were investigated between plasma selenium (PlSe) and whole blood glutathione peroxidase activity (WBGPx) and allergy-related health outcomes including asthma, wheeze, hayfever, rhinitis, eczema and rash. RESULTS: Wellington children had greater PlSe and WBGPx than Christchurch children (P < 0.001 for both). PlSe (P = 0.004) and WBGPx (P = 0.03) were lower in children exposed to environmental smoke, but differences were no longer significant after adjustment for study location, current household smoking (5-6 years), maternal smoking during pregnancy, family history (either parent with asthma, eczema or hayfever), prioritized ethnicity (Maori, Pacific peoples, Other, European), gender, season born, number of siblings, New Zealand Deprivation Index and body mass index at 6 years. Analysis of PlSe or WBGPx as continuous variables or of quartiles of PlSe with health outcomes showed no significant associations after adjustment. Univariate analysis of quartiles of PlSe and WBGPx with persistent wheeze showed significant inverse trends (P = 0.005 for both), but these reduced after adjustment. CONCLUSIONS AND CLINICAL RELEVANCE: Our results do not support a strong association between selenium status and the high incidence of asthma in New Zealand. However, there was a modest association between lower PlSe and WBGPx activity and higher incidence of persistent wheeze.

Respiratory health and lung research in New Zealand.

This article summarizes the recent history of respiratory research in New Zealand which was triggered by an epidemic of asthma mortality in the 1980s and which led to the rapid emergence of quality research groups. This unique event led to major initiatives to improve the standards of care for people with asthma in New Zealand. Perspectives on other lung health issues including tobacco control, the COPD epidemic and the emergence of bronchiectasis as a serious respiratory disease are also provided.

Community-acquired pneumonia: influence of management practices on length of hospital stay.

AIMS: To identify variation in the management of -community-acquired pneumonia between two New Zealand hospitals and the factors that may account for any differences. METHODS: A 12-month, prospective two-centre study was conducted. Between July 1999 and July 2000, 474 adult patients with community-acquired pneumonia were enrolled: 304 in Christchurch Hospital and 170 in Waikato Hospital. The patients were similar in age, sex, prior antibiotic use and comorbidity. There was no significant difference in the clinical outcomes for the patients at the two centres. RESULTS: The mean duration of i.v. antibiotic therapy was 1.7 versus 3.0 days (P < 0.001) and length of stay (LOS) was 3.0 versus 5.9 days (P < 0.001) for Waikato and Christchurch Hospitals, respectively. Using multivariate analysis, we could account for 61% of the observed variation in LOS. Duration of i.v. antibiotic therapy independently accounted for 16% of variation in LOS compared with age (2%), chronic obstructive pulmonary disease, duration of fever, intensive care unit admission and centre of admission (all <1%). For the duration of i.v. antibiotics, centre of admission, largely reflecting clinician practice at each centre, independently accounted for 13% of variation, compared with duration of fever (5%), admission to the Intensive Care Unit (4%), Pneumonia Severity Index score (3%) and bacteraemia (3%). CONCLUSION: Of the identifiable factors, variations in clinician behaviour outweighed the influence of patient factors on the duration of i.v. antibiotic therapy, which in turn was the major determinant of LOS for patients hospitalised with community-acquired pneumonia. An early switch from i.v. to oral antibiotic therapy in conjunction with early discharge planning may significantly reduce LOS without compromising patient outcomes.

Defining community acquired pneumonia severity on presentation to hospital: an international derivation and validation study.

BACKGROUND: In the assessment of severity in community acquired pneumonia (CAP), the modified British Thoracic Society (mBTS) rule identifies patients with severe pneumonia but not patients who might be suitable for home management. A multicentre study was conducted to derive and validate a practical severity assessment model for stratifying adults hospitalised with CAP into different management groups. METHODS: Data from three prospective studies of CAP conducted in the UK, New Zealand, and the Netherlands were combined. A derivation cohort comprising 80% of the data was used to develop the model. Prognostic variables were identified using multiple logistic regression with 30 day mortality as the outcome measure. The final model was tested against the validation cohort. RESULTS: 1068 patients were studied (mean age 64 years, 51.5% male, 30 day mortality 9%). Age >/=65 years (OR 3.5, 95% CI 1.6 to 8.0) and albumin <30 g/dl (OR 4.7, 95% CI 2.5 to 8.7) were independently associated with mortality over and above the mBTS rule (OR 5.2, 95% CI 2.7 to 10). A six point score, one point for each of Confusion, Urea >7 mmol/l, Respiratory rate >/=30/min, low systolic(<90 mm Hg) or diastolic (/=65 years (CURB-65 score) based on information available at initial hospital assessment, enabled patients to be stratified according to increasing risk of mortality: score 0, 0.7%; score 1, 3.2%; score 2, 3%; score 3, 17%; score 4, 41.5% and score 5, 57%. The validation cohort confirmed a similar pattern. CONCLUSIONS: A simple six point score based on confusion, urea, respiratory rate, blood pressure, and age can be used to stratify patients with CAP into different management groups.

Clinical experience and pre-test probability scores in the diagnosis of pulmonary embolism.

BACKGROUND: The Geneva and Wells pre-test probability scores are intended to replace empirical assessment of patients with suspected pulmonary embolism (PE). The effect of clinical experience on the inter-rater variability of these scores, and on empirical judgement, is unknown. AIM: To determine whether medical staff appointment grade affects the inter-rater variability of these pre-test probability scores, or empirical assessment, in patients with suspected PE. DESIGN: Questionnaire survey. METHODS: Doctors were grouped by grade (mean number of years since graduation+/-SEM): house officers 0.7+/-0.2, registrars 6.3+/-0.6, consultants 25+/-4 and applied pre-test probability scores to actual case scenarios. RESULTS: The Geneva score was the most consistent method of determining pre-test probability and was unaffected by clinical experience (Geneva kappa=0.73, Wells kappa=0.38, empirical kappa=0.23, p<0.001 ). With empirical judgement, inter-rater variability was inversely proportional to clinical experience (house officers kappa=0.37, registrars kappa=0.24, consultants kappa= 0.16, p<0.05). DISCUSSION: The Geneva score was the least variable method and can be applied by junior or senior doctors. Using empirical judgement, junior doctors were more likely to agree on the pre-test probability of PE than were their more senior colleagues. This may imply that as physicians gain experience, they recognize that the diagnosis of PE can be difficult to assess and are reluctant to exclude it on clinical grounds.

Particulate air pollution and hospital admissions in Christchurch, New Zealand.

AIMS: Winter air pollution in Christchurch is dominated by particulate matter from solid fuel domestic heating. The aim of the study was to explore the relationship between particulate air pollution and admissions to hospital with cardio-respiratory illnesses. METHODS: Particulate air pollution statistics (PM10) were obtained from the Canterbury Regional Council monitoring station in the city. The New Zealand Health Information Service provided data on admissions to the Princess Margaret and Christchurch Hospitals for the period June 1988 through December 1998 for both adults and children with cardiac and respiratory disorders. The relationship between PM10 and admissions was explored using a time series analysis approach controlling for weather variables. Missing values were interpolated from carbon monoxide data for the same time period, as carbon monoxide and PM10 were highly correlated. RESULTS: There was a significant association between PM10 levels and cardio-respiratory admissions. For all age groups combined there was a 3.37% increase in respiratory admissions for each interquartile rise in PM10 (interquartile value 14.8 mcg/m3). There was also a 1.26% rise in cardiac admissions for each interquartile rise in PM10. There was no relationship between PM10 and admissions for appendicitis, the control condition selected. CONCLUSIONS: In keeping with overseas studies, there is evidence in Christchurch of a relationship between ambient particulate levels and admissions with cardiac and respiratory illnesses. The size of the effect is consistent with overseas data, with the greatest impact for respiratory disorders. IMPLICATIONS: These results indicate that measures to control ambient particulate levels have the potential to reduce hospital admissions for cardio-respiratory illnesses.

Evaluation of a rapid immunochromatographic test for detection of Streptococcus pneumoniae antigen in urine samples from adults with community-acquired pneumonia.

Streptococcus pneumoniae is the most common cause of community-acquired pneumonia but is undoubtedly underdiagnosed. Isolation of S. pneumoniae from blood is specific but lacks sensitivity, while isolation of S. pneumoniae from sputum may represent colonization. We evaluated a new immunochromatographic test (NOW S. pneumoniae urinary antigen test; Binax, Portland, Maine) that is simple to perform and that can detect S. pneumoniae antigen in urine within 15 min. Urine samples from 420 adults with community-acquired pneumonia and 169 control patients who did not have pneumonia were tested. Urine from 315 (75%) of the pneumonia patients and all controls was tested both before and after 25-fold concentration, while the remaining 105 samples were only tested without concentration. S. pneumoniae urinary antigen tests were positive for 120 (29%) patients with pneumonia and for none of the controls. Of the urine samples tested with and without concentration, 96 were positive, of which 6 were positive only after concentration. S. pneumoniae antigen was detected in the urine from 16 of the 20 (80%) patients with blood cultures positive for S. pneumoniae and from 28 of the 54 (52%) patients with sputum cultures positive for S. pneumoniae. The absence of S. pneumoniae antigen in the urine from controls suggests that the specificity is high. Concentration of urine prior to testing resulted in a small increase in yield. The NOW S. pneumoniae urinary antigen test should be a useful adjunct to culture for determining the etiology of community-acquired pneumonia in adults.

The use of warfarin in Christchurch for the treatment of venous thromboembolism.

AIMS: To identify the actual duration of warfarin therapy received by patients being treated for venous thromboembolism (VTE) compared to that initially intended. To determine the incidence of major haemorrhage during therapy. METHODS: The subjects were 505 consecutive medical inpatients who were referred for a lung scan because of suspected pulmonary embolism. Three years following the discharge of the last patient, hospital notes, local and national computer databases were searched for subsequent relevant events. Surviving subjects were also contacted by telephone or letter. RESULTS: 115/505 (23%) received warfarin therapy for VTE. Direct personal contact was made with 314/352 (89%) surviving patients, including 79/82 (98%) surviving patients who were on warfarin. The intended duration of therapy was specified initially in 60/115 treated cases (52%), and these patients were less likely to be still receiving warfarin 3-4 years later (p<0.001). Indefinite therapy was initially recommended in 11/115 cases (10%), but 26/79 surviving subjects (32%) were known to be still receiving warfarin 3-4 years later. Seven treated subjects had a diagnosed recurrence of VTE. There were no clear indications for prolonged therapy in the remainder. Major haemorrhage occurred eighteen times among 115 treated patients (16%), and in two of these warfarin associated bleeding was considered to be the cause of death. None of these events was reported to the Centre for Adverse Reactions Monitoring. CONCLUSIONS: The intended duration of therapy was often unclear and warfarin was generally continued for much longer than is currently considered necessary. Haemorrhagic events were relatively common and were not reported.

Bone mineral density in subjects with mild asthma randomised to treatment with inhaled corticosteroids or non-corticosteroid treatment for two years.

BACKGROUND: Inhaled corticosteroids are clearly beneficial for patients with asthma of moderate severity, but the risks and benefits of using them in patients with milder asthma are less clear. We have compared the change in bone mineral density over 2 years in adults with mild asthma randomised to receive an inhaled corticosteroid or non-corticosteroid treatment. METHODS: Subjects with mild asthma (mean forced expiratory volume in one second (FEV(1)) 86% predicted, mean age 35 years, taking beta agonists only) were randomised to receive inhaled budesonide, inhaled beclomethasone dipropionate, or non-corticosteroid treatment for 2 years in a prospective randomised open study in 19 centres in France, New Zealand, Spain, and the UK. The corticosteroid dose was adjusted according to a written self-management plan. The main outcome measure-change in bone mineral density after 6, 12, and 24 months-was measured "blind". Secondary outcomes included lung function, the relation between change in bone density and inhaled steroid dose and change in biochemical markers of bone metabolism. RESULTS: Of 374 subjects randomised, 239 (64%) completed the study and were included in the analysis. The median daily doses of inhaled budesonide (n=87) and beclomethasone (n=74) were 389 microg and 499 microg, respectively. Subjects treated with an inhaled corticosteroid had better asthma control than those in the reference group (n=78). Change in bone mineral density did not differ between the three groups over the 2 years, nor did it correlate with changes in markers of bone metabolism. The mean change in bone mineral density over 2 years in the budesonide, beclomethasone dipropionate, and reference groups was 0.1%, -0.4%, and 0.4% for the lumbar spine and -0.9%, -0.9%, and -0.4% for neck of the femur. Mean daily dose of inhaled steroid was related to reduction in bone mineral density at the lumbar spine but not at the femoral neck. CONCLUSION: In subjects with mild asthma an inhaled corticosteroid provided better asthma control than alternative non-corticosteroid treatment with no difference in change in bone mineral density over 2 years. The relation between dose of inhaled corticosteroid and change in bone density at the lumbar spine may be due to a direct effect of inhaled corticosteroids on bone. Since inhaled steroid dose is also related inversely to lung function, an effect of asthma severity on bone density was also possible.

The health effects of particulate air pollution - a Christchurch perspective.

Air quality in Christchurch has been debated widely over the last 30 years and at present there is a Draft Plan from the Canterbury Regional Council which has the main aim of improving air quality in the region. It has been shown in an inventory of emissions, that the main source of particulate pollution in the city is the use of solid fuel domestic heating appliances such as open fires and wood burners. Pollution from road traffic is considered a significant contributor to other contaminants but is less that 10% for particulate. There is local evidence that during the winter months, when atmospheric inversion conditions occur, levels of PM10 (particulate matter less than 10 µm in diameter) exceed local guidelines (50 mcg m(-3) -24 hr average) approximately 30 times each year. Research performed in Christchurch suggests that these levels of air pollution account for both premature mortality and an increase in symptoms and medication requirements in susceptible sub-groups such as those with chronic obstructive airways disease. Ongoing research is planned in Christchurch and a collaborative approach between public health physicians, biostatisticians, toxicologists and clinical researchers is likely to yield further useful information which will inform the decision-making process by the Canterbury Regional Council.

Asthma exacerbations during long term beta agonist use: influence of beta(2) adrenoceptor polymorphism.

BACKGROUND: Polymorphisms of the beta(2) adrenoceptor influence receptor function in vitro and asthma phenotypes in vivo. However, their importance in determining responses to inhaled beta agonist treatment has not been clearly defined. METHODS: In a retrospective analysis of previously published data we have examined relationships between polymorphisms at codons 16 and 27 of the beta(2) adrenoceptor and clinical outcomes in a randomised, placebo controlled, crossover trial of regularly scheduled salbutamol and salmeterol in 115 patients with mild to moderate asthma. Genotyping was obtained for positions 16 and 27 in 108 and 107 patients, respectively. For position 16, 17 patients (16%) were homozygous Arg-Arg, 40 (37%) were heterozygous Arg-Gly, and 51 (47%) were homozygous Gly-Gly. RESULTS: Within the homozygous Arg-16 group major exacerbations were more frequent during salbutamol treatment than with placebo (1.91 (95% CI 1.07 to 3.12) per year versus 0.81 (95% CI 0.28 to 1.66) per year; p = 0.005). No significant treatment related differences occurred for heterozygous Arg-Gly patients (salbutamol 0.11 (95% CI 0.01 to 0.40), placebo 0.54 (95% CI 0.26 to 1.00) exacerbations per year) or homozygous Gly-16 patients (salbutamol 0.38 (95% CI 0.17 to 0.73), placebo 0.30 (95% CI 0.12 to 0.61) exacerbations per year). No adverse changes occurred for any position 16 subgroup with salmeterol. There was no significant relationship between position 27 genotypes and treatment related outcomes. CONCLUSION: Homozygous Arg-16 patients are susceptible to clinically important increases in asthma exacerbations during chronic dosing with the short acting beta(2) agonist salbutamol.

Nosocomial pneumonia in adult general medical and surgical patients at Christchurch Hospital.

AIMS: To determine the incidence, microbial cause, and outcome of nosocomial pneumonia in adult general medical and surgical patients at Christchurch Hospital. METHOD: A one-year prospective study of consecutive patients developing nosocomial pneumonia in a university-affiliated hospital. Expanded diagnostic laboratory testing was undertaken to identify the microbial cause of pneumonia. RESULTS: We recruited 126 patients, which represented an incidence of 6.1 per 1,000 admissions. Only 52 (41%) patients submitted sputum that satisfied the cytological screening criteria for testing. A microbial cause was identified in 47 cases (37%): the most common was Legionella spp. (sixteen cases), followed by Influenza A (six cases) and Staphylococcus aureus (four cases). We did not identify an environmental source of the Legionella species. Fourteen patients (11%) died as a consequence of pneumonia and nearly all of these had significant comorbidity. Renal impairment, alcohol excess, and severity of pneumonia were the most powerful predictors of a fatal outcome by univariate analysis. CONCLUSIONS: In most patients we did not identify a microbial cause of pneumonia; when we did, Legionella species were the most common, although this micro-organism has a long incubation period so some subjects may have acquired it before admission. These results guide preventative efforts, diagnostic testing and selection of antimicrobial therapy for nosocomial pneumonia in our hospital.

Establishment of a smoking cessation programme in primary and secondary care in Canterbury.

AIMS: Smokescreen for the 1990's is a smoking cessation programme devised for use in primary care in Australia. It is based on the 'readiness to change' model where smokers are categorised as being 'ready', 'unsure', or 'not ready' to quit smoking. Those in the 'ready' group are encouraged to set a quit date and offered nicotine replacement therapy. Those in the unsure group receive brief motivational intervention, and those 'not ready' are given simple health advice. The aims of the study were to evaluate the process and outcome of establishing this program in primary and secondary care in Christchurch. METHODS: Process evaluation involved all staff participating in the program. Patient outcomes including quit rates were assessed by interview six months after enrollment. RESULTS: Implementation was successful with 59 general practitioners, 49 practice nurses and 294 hospital staff receiving education in the use of the programme. Nine hundred and seven patients (smokers) were enrolled in the study, 347 from primary care and 560 from Christchurch Hospital. The point prevalence abstinence rate at 6 months was 10.4% for the primary care sample and 17% for the secondary care group, with an overall rate of 14.4%. CONCLUSIONS: The programme was successfully implemented across primary and secondary care with an acceptable quit rate at 6 months.

Effects of terbutaline and budesonide on sputum cells and bronchial hyperresponsiveness in asthma.

Previous studies have shown that the regular administration of short acting beta-agonists can be associated with adverse effects on airway caliber and bronchial hyperresponsiveness (BHR) and that this may occur through a proinflammatory mechanism. The aim was to explore possible adverse effects of high-dose beta-agonist therapy and to assess any adverse interaction with corticosteroids. We undertook a randomized, crossover study to investigate the effects of 6 wk of treatment with regular terbutaline (1 mg four times a day), regular budesonide (400 microg twice a day), combined treatment, and placebo in subjects with mild to moderate asthma. Major endpoints were PD(15) saline, PD(20) methacholine, and induced sputum differential cell counts. Thirty-four subjects were randomized and 28 completed the study. PD(15) saline decreased on terbutaline alone compared with placebo treatment and on combined treatment compared with budesonide alone (mean fold decrease of 0.57 [95% CI = 0.36, 0.90] and 0.65 [95% CI = 0.43, 0.97], respectively). PD(20) methacholine was not affected by the use of terbutaline either alone or in combination with budesonide. The percentage of eosinophils in induced sputum increased during terbutaline treatment alone compared with placebo (median 8.3% versus 4.4%, p = 0.049). The addition of terbutaline to budesonide did not affect the percentage of eosinophils compared with budesonide treatment alone. These findings support the hypothesis that short-acting beta-agonists have a permissive effect on airway inflammation and that when used in high dose there may be an unfavorable interaction with inhaled corticosteroids.

Daily mortality in relation to weather and air pollution in Christchurch, New Zealand.

OBJECTIVE: To investigate the relationship between the daily number of deaths, weather and ambient air pollution. METHOD: An ecological study. We assembled daily data for the city of Christchurch, New Zealand (population 300,000) from June 1988 to December 1993. We used Poisson regression models, controlling for season using a parametric method. RESULTS: Above the third quartile (20.5 degrees C) of maximum temperature, an increase of 1 degree C was associated with a 1% (95% CI: 0.4 to 2.1%) increase in all-cause mortality and a 3% (0.1 to 6.0%) increase in respiratory mortality. An increase in PM10 of 10 micrograms/m3 was associated (after a lag of one day) with a 1% (0.5 to 2.2%) increase in all-cause mortality and a 4% (1.5 to 5.9%) increase in respiratory mortality. We found no evidence of interaction between the effects of temperature and particulate air pollution. CONCLUSIONS: High temperatures and particulate air pollution are independently associated with increased daily mortality in Christchurch. The fact that these results are consistent with those of similar studies in other countries strengthens the argument that the associations are likely to be causal. IMPLICATIONS: These findings contribute to evidence of health consequences of fuel combustion, both in the short term (from local air pollution) and in the long term (from the global climatic effects of increased atmospheric CO2).

The pharmacokinetics of oral fleroxacin and ciprofloxacin in plasma and sputum during acute and chronic dosing.

AIMS: To examine the pharmacokinetics of ciprofloxacin and fleroxacin in plasma and sputum of patients with an acute exacerbation of chronic bronchitis or bronchiectasis following the first dose and again during the third day of treatment. METHODS: Twelve patients, aged >35 years, with acute infective exacerbation of bronchitis or bronchiectasis were allocated randomly to treatment with either fleroxacin 400 mg daily or ciprofloxacin 500 mg twice daily in an open, parallel group design. Plasma and sputum were collected during the first and third days of treatment. The time course of concentrations in sputum was modelled assuming that it acted as a negligibly small compartment of distribution. RESULTS: The mean sputum to plasma ratios of both ciprofloxacin and fleroxacin were approximately 1 on both days 1 and 3. Peak concentrations of ciprofloxacin in sputum were achieved 1.6 (95% CI on mean difference 0.8-2.3) and 1.2 (0.4-1.9) h later than in plasma on day 1 and day 3, respectively (mean difference +/- 95% confidence interval). For fleroxacin, the corresponding delay in time to peak concentrations was less marked and not significant. Fleroxacin accumulated in plasma (accumulation index 1.52+/-0.07) and sputum (accumulation index 1.79+/-0.39) from day 1 to day 3. Accumulation did not occur for ciprofloxacin because the dose interval (12 h) was considerable longer than its half life (3-4 h). CONCLUSIONS: The sputum to plasma ratio of ciprofloxacin and fleroxacin is approximately 1. The time to peak concentrations of ciprofloxacin in sputum is slightly delayed compared with plasma. Fleroxacin accumulates over time in both plasma and sputum consistent with its longer half-life.

Tolerance to beta-agonists during acute bronchoconstriction.

Previous reports suggest that regular use of beta-agonists does not lead to tolerance to their bronchodilator effects. However, most studies have been conducted in stable asthma. This study investigates whether bronchodilator tolerance can be demonstrated during acute bronchoconstriction. Thirty-four asthmatic subjects were treated with 6 weeks inhaled terbutaline (1 mg q.i.d.), budesonide (400 microg, b.i.d.), both drugs or placebo in a randomized, double-blind, cross-over study. After each treatment methacholine was administered to induce a 20% fall in the forced expiratory volume in one second (FEV1). The response to inhaled salbutamol 100, 100, 200 microg at 5 min intervals) was then measured. Dose-response curves were compared using an analysis of covariance. Pre-methacholine FEV1, the highest pre-methacholine FEV1, the fall in FEV1 induced by methacholine and the logarithm of the provocative dose of methacholine required to induce the 20% fall in FEV1 (PD20) were used as covariates. There was a significantly reduced response to salbutamol after 6 weeks terbutaline treatment: the mean (95% confidence intervals (CI)) area under the dose-response curve was reduced by 36% (24, 47) compared to placebo (p<0.0001). The reduction in bronchodilator response was not affected by concomitant treatment with budesonide. Significant tolerance to the bronchodilator effect of inhaled beta-agonists may be demonstrated when tested during acute bronchoconstriction. Continuous treatment with inhaled beta-agonists may lead to a reduced response to emergency beta-agonist treatment during asthma exacerbations.

Survey of the use of thromboprophylaxis for medical patients at Christchurch Hospital.

AIM: To determine the level of utilisation of thromboprophylaxis in relation to risk factors for medical patients at Christchurch Hospital. METHODS: All medical wards were surveyed three times over a 12-week period from January 1998. Patients currently under investigation for venous thromboembolism were excluded, as were those currently receiving anticoagulant treatment for unrelated disorders. Primary prophylaxis was defined as the use of low-dose heparins or elastic stockings in asymptomatic patients. Patients with two or more risk factors were defined as being at high risk. RESULTS: Three hundred and eighty-seven patients were interviewed, of whom 80% were considered to be potentially eligible for primary prophylaxis. One hundred and one patients (33%) were at high risk, of whom 20 (20%) were given primary prophylaxis. Cancer, confinement to bed, recent surgery and heart failure were the most common risk factors. Elastic stockings and low-dose heparin were employed in the same proportion of high risk cases but no patient received both. Patients with cancer were less likely to receive thromboprophylaxis than those with the other risk factors. Overall, only about 7% of high-risk patients received thromboprophylaxis for more than 75% of the duration of their stay in hospital. CONCLUSION: Thromboprophylaxis is underutilised at Christchurch Hospital. Guidelines are required and audits of compliance are indicated.

Legionella, Chlamydia pneumoniae and Mycoplasma infection in patients admitted to Christchurch Hospital with pneumonia.

AIMS: To determine the incidence, clinical features and outcome of community acquired pneumonia caused by Mycoplasma pneumoniae, Legionella species, Coxiella burnetti, Chlamydia pneumoniae and Chlamydia psittaci requiring admission to hospital. METHODS: Over 12 months the clinical findings and severity of pneumonia were recorded prospectively. Sputum, blood, serum and urine samples were collected for diagnostic testing. Management was supervised by the admitting medical team. Subjects were followed-up six weeks after discharge. RESULTS: Two hundred and fifty-five patients met the entry criteria of whom 20 died, including five who had Legionella infection. M pneumoniae (16%) infection was more often of mild/moderate severity (95%), occurred in a younger age group (mean age 31.4 years, p=0.002), with more frequent myalgia and headache. The length of hospital stay was shorter and clearing of chest radiograph and return to normal activity occurred more rapidly in this group of patients. Legionellosis was common as judged by culture and serological testing (26 cases, 11%) and a further 22 cases were identified by polymerase chain reaction. Legionella infection was not distinguishable clinically from other pneumonias. C pneumoniae was uncommon (8 cases, 3%). C burnetti and C psittaci were not identified in this study. CONCLUSIONS: Some cases of pneumonia caused by Mycoplasma pneumoniae can be identified at presentation, however pneumonia due to Legionella is not distinguishable on clinical grounds. Development of molecular diagnostic techniques may enable therapy to be directed against specific organisms earlier in the course of the disease.