Nasopharyngeal carriage and macrolide resistance in Indigenous children with bronchiectasis randomized to long-term azithromycin or placebo.

Although long-term azithromycin decreases exacerbation frequency in bronchiectasis, increased macrolide resistance is concerning. We investigated macrolide resistance determinants in a secondary analysis of a multicenter randomized controlled trial. Indigenous Australian children living in remote regions and urban New Zealand Maori and Pacific Islander children with bronchiectasis were randomized to weekly azithromycin (30 mg/kg) or placebo for up to 24 months and followed post-intervention for up to 12 months. Nurses administered and recorded medications given and collected nasopharyngeal swabs 3-6 monthly for culture and antimicrobial susceptibility testing. Nasopharyngeal carriage of Haemophilus influenzae and Moraxella catarrhalis was significantly lower in azithromycin compared to placebo groups, while macrolide-resistant Streptococcus pneumoniae and Staphylococcus aureus carriage was significantly higher. Australian children, compared to New Zealand children, had higher carriage overall, significantly higher carriage of macrolide-resistant bacteria at baseline (16/38 versus 2/40 children) and during the intervention (69/152 versus 22/239 swabs), and lower mean adherence to study medication (63 % versus 92 %). Adherence ≥70 % (versus <70 %) in the Australian azithromycin group was associated with lower carriage of any pathogen [odds ratio (OR) 0.19, 95 % confidence interval (CI) 0.07-0.53] and fewer macrolide-resistant pathogens (OR 0.34, 95 % CI 0.14-0.81). Post-intervention (median 6 months), macrolide resistance in S. pneumoniae declined significantly in the azithromycin group, from 79 % (11/14) to 7 % (1/14) of positive swabs, but S. aureus strains remained 100 % macrolide resistant. Azithromycin treatment, the Australian remote setting, and adherence <70 % were significant independent determinants of macrolide resistance in children with bronchiectasis. Adherence to treatment may limit macrolide resistance by suppressing carriage.

Screening and treating pulmonary arterial hypertension in a tertiary hospital-based multidisciplinary clinic: the first 200 patients.

BACKGROUND: Pulmonary arterial hypertension (PAH) is an increasingly recognised serious illness with insidious onset, delayed diagnosis, complex diagnostic algorithms and poor prognosis, but with recently available effective treatments. AIMS: To efficiently diagnose and to offer treatment for PAH, we established a multidisciplinary service in 2005, where patients attend a clinic staffed by specialists in cardiology, respiratory medicine, rheumatology and immunology in a tertiary referral hospital setting. METHODS: We studied the first 200 patients referred. Serology, echocardiography, lung function tests, high-resolution computed tomography, World Health Organisation Class determination and 6-min walk tests and/or right heart catheterisation were performed, as clinically indicated. RESULTS: Of the 200 patients seen, 66 had confirmed pulmonary hypertension (mean pulmonary artery pressure > 25 mmHg) diagnosed on echocardiography ± right heart catheterisation. Of these patients, 58 had catheter-proven PAH (mean pulmonary artery pressure > 25 mmHg with mean wedge pressure < 15 mmHg). Underlying diagnoses for the confirmed PAH patients were idiopathic (32), scleroderma-associated (14), other connective tissue disease (4) and associated with congenital heart disease (8). Patients with confirmed PAH were commenced on PAH-specific therapy--initially bosentan in the majority but sildenafil, and iloprost were occasionally used initially for patient-specific reasons. Median time from when the patient first called the clinic to prescription of therapy was 16 days (interquartile range; 0-31 days). All surviving patients with PAH have attended for regular 6-monthly follow-up visits with a 100% retention rate up to 4 years. CONCLUSION: A multidisciplinary clinic can provide efficient diagnosis and rapid triage to PAH-specific therapy, if appropriate. Retention rates remain high, at follow up.

Otitis media at 6-monthly assessments of Australian First Nations children between ages 12-36 months: Findings from two randomised controlled trials of combined pneumococcal conjugate vaccines.

OBJECTIVES: In remote communities of northern Australia, First Nations children with hearing loss are disproportionately at risk of poor school readiness and performance compared to their peers with no hearing loss. The aim of this trial is to prevent early childhood persisting otitis media (OM), associated hearing loss and developmental delay. To achieve this, we designed a mixed pneumococcal conjugate vaccine (PCV) schedule that could maximise immunogenicity and thereby prevent bacterial otitis media (OM) and a trajectory of educational and social disadvantage. METHODS: In two sequential parallel, open-label, randomised controlled trials, eligible infants were first allocated 1:1:1 to standard or mixed PCV primary schedules at age 28-38 days, then at age 12 months to a booster dose (1:1) of 13-valent PCV, PCV13 (Prevenar13®, +P), or 10-valent pneumococcal non-typeable Haemophilus influenzae protein D conjugated vaccine, PHiD-CV10 (Synflorix®, +S). Here we report findings of standardised ear assessments conducted six-monthly from age 12-36 months, by booster dose. RESULTS: From March 2013 to September 2018, 261 children were allocated to booster + P (n = 131) or + S (n = 130). There were no significant differences in prevalence of any OM diagnosis by booster dose or when stratified by primary schedule. We found high, almost identical prevalence of OM in both boost groups at each age (for example 88% of 129 and 91% of 128 children seen, respectively, at primary endpoint age 18 months, difference -3% [95% Confidence Interval -11, 5]). At each age prevalence of bilateral OM was 52%-78%, and tympanic membrane perforation was 10%-18%. CONCLUSION: Despite optimal pneumococcal immunisation, the high prevalence of OM persists throughout early childhood. Novel approaches to OM prevention are needed, along with improved early identification strategies and evaluation of expanded valency PCVs.

Effectiveness of 7-valent pneumococcal conjugate vaccine against radiologically diagnosed pneumonia in indigenous infants in Australia.

OBJECTIVE: To evaluate the effectiveness of the 7-valent pneumococcal conjugate vaccine (PCV7) in preventing pneumonia, diagnosed radiologically according to World Health Organization (WHO) criteria, among indigenous infants in the Northern Territory of Australia. METHODS: We conducted a historical cohort study of consecutive indigenous birth cohorts between 1 April 1998 and 28 February 2005. Children were followed up to 18 months of age. The PCV7 programme commenced on 1 June 2001. All chest X-rays taken within 3 days of any hospitalization were assessed. The primary endpoint was a first episode of WHO-defined pneumonia requiring hospitalization. Cox proportional hazards models were used to compare disease incidence. FINDINGS: There were 526 pneumonia events among 10,600 children - an incidence of 3.3 per 1000 child-months; 183 episodes (34.8%) occurred before 5 months of age and 247 (47.0%) by 7 months. Of the children studied, 27% had received 3 doses of vaccine by 7 months of age. Hazard ratios for endpoint pneumonia were 1.01 for 1 versus 0 doses; 1.03 for 2 versus 0 doses; and 0.84 for 3 versus 0 doses. CONCLUSION: There was limited evidence that PCV7 reduced the incidence of radiologically confirmed pneumonia among Northern Territory indigenous infants, although there was a non-significant trend towards an effect after receipt of the third dose. These findings might be explained by lack of timely vaccination and/or occurrence of disease at an early age. Additionally, the relative contribution of vaccine-type pneumococcus to severe pneumonia in a setting where multiple other pathogens are prevalent may differ with respect to other settings where vaccine efficacy has been clearly established.

The expanding role of extracorporeal membrane oxygenation retrieval services in Australia.

Herein we detail the cases of three patients transferred on veno-arterial extracorporeal membrane oxygenation (VA ECMO) from a tertiary referral hospital to an ECMO centre. We highlight the benefits of such a transfer and offer this as a model of care for unwell patients likely to require a prolonged period of ECMO support.

PEEP and "reverse mismatch". A case where less PEEP is best.

A V/Q lung scan was obtained in a patient with LLL collapse who was receiving IPPV and PEEP. This revealed absent ventilation and hyperperfusion to the collapsed lobe. After a reduction in PEEP from 12 to 5 cm H2O, a repeat V/Q scan showed a more even distribution of pulmonary perfusion. Arterial hypoxemia improved.

Nocturnal nasal IPPV stabilizes patients with cystic fibrosis and hypercapnic respiratory failure.

Nocturnal nasal intermittent positive pressure ventilation (nIPPV) has been used successfully in the management of patients with respiratory failure due to chest wall deformity and neuromuscular disease. In order to determine if nIPPV is useful in patients with cystic fibrosis (CF) complicated by respiratory failure, we treated four hypercapnic patients for up to 18 months. All patients had failed to respond to intensive conventional therapy, including nocturnal nasal CPAP in three of the patients. Within a few days of commencing nIPPV, all reported improved length and quality of sleep. There was lessening of the degree of hypercapnia and an increase in respiratory muscle strength. After stabilization in the hospital, all patients were able to be discharged home receiving nocturnal assisted ventilation. The improvements seen in these patients have been maintained for up to 18 months. We believe nIPPV offers an effective therapeutic approach for patients with end-stage CF in hypercapnic respiratory failure and may be particularly advantageous for those awaiting heart-lung transplant.

Etiology of acute lower respiratory tract infection in Central Australian Aboriginal children.

BACKGROUND: Aboriginal children in central Australia have attack rates for acute lower respiratory tract infection (ALRI) that are similar to those in developing countries. Although mortality rates are much lower than in developing countries, morbidity is high and ALRI is still the leading cause of hospitalization. However, there are no data on the etiology of ALRI in this population. METHODS: We prospectively studied 322 cases of ALRI in 280 Aboriginal children admitted to the hospital. Blood, urine and nasopharyngeal aspirate samples were examined for evidence of bacterial, viral and chlamydial infection. RESULTS: The combination of blood culture, viral studies and chlamydial serology provided at least 1 etiologic agent in 170 of 322 (52.5%) cases. Assays for pneumolysin immune complex and pneumolysin antibody increased etiologic diagnosis to 219 (68.0%). Blood cultures were positive in 6% but pneumolysin immune complex and pneumolysin antibody studies were positive in one-third of cases. Evidence of viral infection was present in 155 (48%) of cases compared with 12% in controls (P < 001). There were only 7 possible cases and 2 definite cases of Chlamydia trachomatis and 3 cases of Chlamydia pneumoniae. Coinfection was common in these children. CONCLUSION: These findings have implications for both standard treatment protocols and vaccine strategies. The high rate of coinfection may make it difficult to develop simple clinical predictors of bacterial infection. In the setting of a developed country with efficient patient evacuation services, management algorithms that focus on disease severity and need for hospital referral will be most useful to health staff in remote communities. Pneumococcal conjugate vaccines will be required to reduce the high attack rate of pneumococcal disease.

Respiratory disease amongst Aborigines in the Pilbara.

Aboriginal communities have a high prevalence of upper and lower respiratory tract disease. One thousand two hundred and eighty seven West Australian Aborigines and 265 non-Aborigines were examined. Twenty nine per cent of Aborigines had lower respiratory tract abnormalities. Amongst 635 Aboriginal children less than 15 years of age, 23% had lower respiratory tract signs--four times the prevalence in 174 non-Aborigines. Twenty six per cent of Aborigines under 10 years of age had signs of otitis media, compared to 3% amongst non-Aborigines. Two hundred and thirty eight (53%) of Aboriginal children less than 10 years of age had nasal discharge, compared to 1.6% of the non-Aboriginal children.

Thalidomide responsive chronic pulmonary GVHD.

A 29-year-old male underwent allogeneic bone marrow transplantation for progressive multiple myeloma. His post-transplant course was complicated by severe chronic pulmonary graft-versus-host disease (GVHD) resistant to cyclosporin A, corticosteroids and azathioprine. The introduction of thalidomide resulted in a dramatic improvement in his lung function which has been maintained even after cessation of thalidomide. He remains well 40 months after transplantation.

Non-CF bronchiectasis: clinical and HRCT evaluation.

Childhood bronchiectasis not related to underlying disease is still common in some populations in affluent countries. The aims of the study were to: 1) describe demographics, 2) evaluate the effectiveness of routine investigations, and 3) determine the relationship between spirometry and radiology scoring systems, in children with chronic suppurative lung disease (CSLD) living in Central Australia. Data of children living in Central Australia aged 70%) and early hospitalisation for pneumonia were common (median age, 0.5 years). Previous admissions for pneumonia were almost universally present and significantly more common than bronchiolitis (95% CI for proportional difference, 0.4-0.51). Although the majority did not have a treatable underlying cause, investigations had significant impact on management in 12.3% of children. None of the chest HRCT scores related to any spirometry data. In conclusion, CSLD is unacceptably common in indigenous children of this region, commences early in life, and is associated with significant comorbidities. Spirometry data do not reflect the severity of lung disease in HRCT scans. While improvement in the living standards is of utmost importance, the medical management that includes thorough investigations of these children should not be neglected.

The effect of a comprehensive, intensive inpatient treatment program on lung function and exercise capacity in patients with cystic fibrosis.

BACKGROUND AND PURPOSE: The purpose of this investigation was to measure the effects of a 10- to 14-day comprehensive, intensive hospital treatment program on peak exercise capacity, endurance capacity, respiratory function, weight change, and maximum inspiratory and expiratory mouth pressures in patients with cystic fibrosis with a pulmonary exacerbation. SUBJECTS: Fourteen young adults with cystic fibrosis admitted to a hospital for an exacerbation of their pulmonary disease were studied. METHODS: Subjects performed pulmonary function tests, inspiratory and expiratory mouth pressure tests, and stationary bicycle exercise tests at admission and discharge. Comprehensive therapy provided during the hospital admission consisted of intravenous antibiotics, physical therapy, high-calorie diet, and daily medical review. RESULTS: The patients showed improvements in forced expiratory volume in 1 second (46%-55% of predicted values) and forced vital capacity (62%-68% of predicted values). Maximum inspiratory and expiratory mouth pressures also improved (118%-131% and 78%-92% of predicted values, respectively). There was a mean weight gain of 2 kg. Maximum work capacity on a bicycle ergometer improved from a mean of 45% to 52% of predicted values. The most impressive result was the marked increase in exercise endurance time from a mean of 9.5 minutes on admission to 16.6 minutes at discharge. CONCLUSION AND DISCUSSION: This study indicates that young adults with cystic fibrosis and an exacerbation of their pulmonary disease obtain measurable benefits from a comprehensive, intensive treatment program, particularly improvement in their capacity for endurance exercise.

Private business: the uptake of confidential HIV testing in remote aboriginal communities on the Anangu Pitjantjatjara Lands.

BACKGROUND AND METHODS: Despite a concentration of risk factors for HIV transmission, many remote Aboriginal communities in central Australia have a low uptake of HIV testing. We studied the uptake of HIV testing in six clinics in remote Aboriginal communities following the introduction of voluntary confidential testing to assess the impact of the intervention and to determine if the program was reaching people most at risk of HIV infection and transmission. SETTING: The study was conducted by Nganampa Health Council, an Aboriginal-controlled health service on the Anangu Pitjantjatjara Lands in the far north-west of South Australia. RESULTS: Since the introduction of confidential coded testing in August 1994 the number of HIV tests provided through the remote clinics has increased from 83 tests/year to 592 tests/year. In the 12-month audit period (August 1, 1995, to July 31, 1996) 62.7% of women aged 20-24 years, 44.6% of people aged 12-40 years and 24% of the total population had an HIV test. Fifty per cent of tests were accounted for by the 15-25 year age groups and 60% of tests related to an STD consult. DISCUSSION: This study shows that a high uptake of HIV testing in high-risk groups can be achieved in remote Aboriginal communities where a high level of confidentiality is maintained.

Regional mucociliary clearance in patients with cystic fibrosis.

This paper reports on a large retrospective analysis of mucociliary clearance (MCC) studies in a group of 59 patients with cystic fibrosis (CF) and 17 age-matched healthy subjects. As many of the CF patients were studied on multiple occasions, a total of 184 patient studies are presented. MCC was measured using a radioaerosol and gamma camera technique. In addition to whole lung clearance, MCC was measured from the central, intermediate, peripheral, basal, mid and apical regions of the lung. MCC was markedly decreased in the CF patient group. Not only was whole lung clearance (14.2 +/- 1.4% vs. 28.0 +/- 3.7%) impaired, but also clearance from the central (19.1 +/- 1.9% vs. 35.6 +/- 4.3%), intermediate (10.7 +/- 1.6% vs. 25.5 +/- 3.7%), apical (12.4 +/- 2.6% vs. 31.6 +/- 4.6%) and mid (14.0 +/- 1.9% vs. 30.4 +/- 4.0%) regions. Attempts were made to identify factors that may have influenced MCC in both the normal subjects and CF patients. Age, gender, body mass index, patient genotype, penetration index, spontaneous cough, and various lung function parameters were entered into a stepwise multiple regression model, but none of the factors proved to be statistically important in determining MCC. Both intrasubject repeatability and intersubject variability estimates are presented for the patients and normal subjects that had multiple studies. The values were found to be remarkably similar for both CF patients and normal subjects and for both intra- and intersubject repeatability. With marked deviation from normal ranges and good repeatability, the measurement of MCC in CF patients would seem to be a valuable outcome measure for clinical trials involving new pharmaceuticals and physical therapy designed to improve removal of secretions from the airways.

Upper airway carriage by Haemophilus influenzae and Streptococcus pneumoniae in Australian aboriginal children hospitalised with acute lower respiratory infection.

When nasopharyngeal secretions from 171 Australian Aboriginal children hospitalized with acute lower respiratory tract infections (ALRI) were cultured selectively for Streptococcus pneumoniae and Haemophilus influenzae, 136 (79.5%) and 151 (88.3%) children yielded 166 and 254 isolates of S. pneumoniae and H. influenzae, respectively. In colonized subjects multiple populations of S. pneumoniae (20% of carriage-positive patients) and H. influenzae (55%) were common. Pneumococci belonging to 27 types or groups were identified. H. influenzae serotype b colonized 16.4% of all children studied. More than one half of 152 children tested were excreting antibiotics at the time of admission to hospital. Significantly fewer children with serum antibiotic residues were colonized with S. pneumoniae than were antibiotic free children. Antibiotic usage had no measurable impact on the isolation rate of H. influenzae.

Pneumococcal vaccine.

Pneumococcal infection is a major health problem in both developed and developing countries. Adult patients with a range of chronic illnesses are at increased risk of both morbidity and mortality from this condition. The currently available 23 valent vaccine is generally not effective in children under 2 years of age or adults with significant immunosuppression. However, case control and cohort studies have established the vaccine's effectiveness in patients with a number of chronic illnesses as well as those undergoing splenectomy. The vaccine is safe and should be more widely used by practitioners with patients who meet the current NHMRC guidelines.

Acute respiratory infections in Australian Aboriginal children: current knowledge and future requirements.

Although inadequately documented, it is clear that acute respiratory infection (ARI) is a major cause of morbidity and hospitalization in Australian Aboriginal children. ARIs continue to cause substantial mortality in Aboriginal children, and they are likely to cause a variety of potentially serious sequelae. The literature emphasizes the importance of pneumonia as a cause of hospitalization of Aboriginal children. There is good evidence that Streptococcus pneumoniae and Haemophilus influenzae are predominant causes of severe pneumonia, but little is known about the importance of other respiratory pathogens, such as respiratory syncytial virus, as causes of ARI in Aboriginal children. Poor living conditions, low birthweight and malnutrition are likely to be important risk factors for ARI in some groups of Aboriginal children. Although broad-ranging economic and environmental changes will be required to bring about a sustained reduction in ARI in Aboriginal children, there should be an emphasis upon correct case management of ARI at the primary care level so as to reduce the need for hospitalization. Some research priorities are discussed.

Impact of recent antibiotics on nasopharyngeal carriage and lower airway infection in Indigenous Australian children with non-cystic fibrosis bronchiectasis.

Indigenous Australian children have increased rates of bronchiectasis. Despite a lack of high-level evidence on effectiveness and antibiotic resistance, these children often receive long-term antibiotics. In this study, we determined the impact of recent macrolide (primarily azithromycin) and ß-lactam antibiotic use on nasopharyngeal colonisation, lower airway infection (>10(4) CFU/mL of bronchoalveolar lavage fluid culture) and antibiotic resistance in non-typeable Haemophilus influenzae (NTHi), Streptococcus pneumoniae and Moraxella catarrhalis isolates from 104 Indigenous children with radiographically confirmed bronchiectasis. Recent antibiotic use was associated with significantly reduced nasopharyngeal carriage, especially of S. pneumoniae in 39 children who received macrolides [odds ratio (OR)=0.22, 95% confidence interval (CI) 0.08-0.63] and 26 children who received ß-lactams (OR=0.07, 95% CI 0.01-0.32), but had no significant effect on lower airway infection involving any of the three pathogens. Children given macrolides were significantly more likely to carry (OR=4.58, 95% CI 1.14-21.7) and be infected by (OR=8.13, 95% CI 1.47-81.3) azithromycin-resistant S. pneumoniae. Children who received ß-lactam antibiotics may be more likely to have lower airway infection with ß-lactamase-positive ampicillin-resistant NTHi (OR=4.40, 95% CI 0.85-23.9). The risk of lower airway infection by antibiotic-resistant pathogens in children receiving antibiotics is of concern. Clinical trials to determine the overall benefit of long-term antibiotic therapy are underway.

Retrieval of critically ill adults using extracorporeal membrane oxygenation: an Australian experience.

PURPOSE: A retrieval program was developed in New South Wales (NSW), Australia to provide extracorporeal membrane oxygenation support (ECMO) for the safe transport of adults with severe, acute respiratory or cardiac failure. We describe the development and results of this program and the impact of the 2009 H1N1 epidemic on this service. METHODS: An observational study of all patients who were retrieved on ECMO support in NSW, from March 1, 2007 to June 1, 2010, was carried out. RESULTS: Forty adult patients were retrieved on ECMO support (median age 34 years). The indications for retrieval were respiratory in 38 patients (of whom 16 were confirmed or suspected H1N1 cases) and cardiac in 2 patients. Two other patients died after referral but before ECMO support could be established. Patients were transported by road (n = 26, 65%), medical retrieval jet (n = 10, 25%) and helicopter (n = 4, 10%). The median retrieval distance was 250 km (range 12-1,960 km). Thirty-four patients (85%) survived to hospital discharge. Survival for respiratory indications was 87% (33/38 patients) and 50% (1/2 patients) for cardiac indications. There were no deaths or major morbidity associated with these retrievals. CONCLUSIONS: Patients with very severe respiratory failure, which was considered to preclude conventional ventilation for safe transfer to tertiary centres, were managed by an ECMO referral and retrieval program in NSW and had a high rate of survival. This program also enhanced the capacity of the state to respond to a surge in demand for ECMO support due to the H1N1 epidemic, although the role of ECMO in respiratory failure is not yet well defined.