Clinical course of chronic suppurative lung disease and bronchiectasis in Alaska Native children

INTRODUCTION

Alaska Native (AN) children from the Yukon Kuskokwim (YK) Delta region have high rates of chronic suppurative lung disease (CSLD), including bronchiectasis. We characterized the clinical progress of an AN adolescent cohort with CSLD/bronchiectasis, and estimated bronchiectasis prevalence trends in this region.

METHODS

The original cohort comprised 41 AN children (originally aged 0.5-8 years) with CSLD/bronchiectasis, recruited between 2005 and 2008, with follow-up in 2015-2016. Clinical assessments, lung function, radiography, medical chart review, and spirometry were obtained. We also conducted data queries of bronchiectasis diagnoses in YK individuals born between 1990 and 2010 to estimate prevalence.

RESULTS

Thirty-four (83%) of the original cohort aged 7.3-17.6 years were reviewed, of whom 14 (41%) had high-resolution computed tomography (HRCT)-confirmed bronchiectasis, eight (24%) had no evidence of bronchiectasis on HRCT scans, while 12 (35%) had not undergone HRCT scans. Annual lower respiratory tract infection (LRTI) frequency decreased with age, although 27 (79%) still had respiratory symptoms, including all with HRCT-confirmed bronchiectasis, who were also more likely than those without confirmed bronchiectasis to have recent wheeze (80 vs 25%, P = 0.005), auscultatory crackles (60 vs 0%, P < 0.001), and lower mean forced expiratory volume in 1-second/forced vital capacity ratio (73 vs 79%, P = 0.03). The bronchiectasis prevalence for YK AN people born during 2000-2009 was 7 per 1000 births, which was lower than previously reported.

CONCLUSION

Despite reduced LRTI frequency, most AN children with CSLD/bronchiectasis had symptoms/signs of underlying lung disease as they entered adolescence. Close clinical follow-up remains essential for managing these patients as they transition to adulthood.

Human T-Lymphotropic Virus type 1c subtype proviral loads, chronic lung disease and survival in a prospective cohort of Indigenous Australians

Background

The Human T-Lymphotropic Virus type 1c subtype (HTLV-1c) is highly endemic to central Australia where the most frequent complication of HTLV-1 infection in Indigenous Australians is bronchiectasis. We carried out a prospective study to quantify the prognosis of HTLV-1c infection and chronic lung disease and the risk of death according to the HTLV-1c proviral load (pVL).

Methodology/Principal findings

840 Indigenous adults (discharge diagnosis of bronchiectasis, 154) were recruited to a hospital-based prospective cohort. Baseline HTLV-1c pVL were determined and the results of chest computed tomography and clinical details reviewed. The odds of an association between HTLV-1 infection and bronchiectasis or bronchitis/bronchiolitis were calculated, and the impact of HTLV-1c pVL on the risk of death was measured.

Radiologically defined bronchiectasis and bronchitis/bronchiolitis were significantly more common among HTLV-1-infected subjects (adjusted odds ratio = 2.9; 95% CI, 2.0, 4.3). Median HTLV-1c pVL for subjects with airways inflammation was 16-fold higher than that of asymptomatic subjects. There were 151 deaths during 2,140 person-years of follow-up (maximum follow-up 8.13 years). Mortality rates were higher among subjects with HTLV-1c pVL ≥1000 copies per 10⁵ peripheral blood leukocytes (log-rank χ² (2df) = 6.63, p = 0.036) compared to those with lower HTLV-1c pVL or uninfected subjects. Excess mortality was largely due to bronchiectasis-related deaths (adjusted HR 4.31; 95% CI, 1.78, 10.42 versus uninfected).

Conclusion/Significance

Higher HTLV-1c pVL was strongly associated with radiologically defined airways inflammation and with death due to complications of bronchiectasis. An increased risk of death due to an HTLV-1 associated inflammatory disease has not been demonstrated previously. Our findings indicate that mortality associated with HTLV-1c infection may be higher than has been previously appreciated. Further prospective studies are needed to determine whether these results can be generalized to other HTLV-1 endemic areas.

The Human T-Lymphotropic Virus type 1 (HTLV-1) infects up to 20 million people worldwide who predominantly reside in resource-limited areas. The virus is associated with a haematological malignancy (adult T-cell leukaemia/lymphoma, ATL), and inflammatory diseases involving organ systems including the spinal cord, eyes and lungs. Determining the outcomes of infection in most HTLV-1 endemic areas is extremely difficult; however, the virus is highly endemic to central Australia where the Indigenous population has access to sophisticated medical facilities. We prospectively followed a large hospital-based cohort of Indigenous Australian adults that was well characterized with regard to base-line comorbid conditions, HTLV-1 serostatus and HTLV-1 proviral load (pVL). A higher baseline HTLV-1 pVL was strongly associated with an increased risk of airway inflammation (bronchitis/bronchiolitis and bronchiectasis) and death, which most often resulted from complications of bronchiectasis. Increased mortality due to an HTLV-1-associated inflammatory condition has not been demonstrated previously. The morbidity and mortality associated with HTLV-1 infection may therefore be substantially higher than has been assumed from an analysis of cohorts of subjects with adult T-cell leukaemia or HTLV-1-associated myelopathy. These findings have important implications for epidemiological research and for determining health care priorities in resource-limited settings.

Hospital admissions for non-cystic fibrosis bronchiectasis in New Zealand

AIM

To investigate hospital admissions for non-cystic fibrosis bronchiectasis during July 1, 2008 to June 30, 2013; and to describe their distribution and annual cost in New Zealand.

METHODS

Admissions with a principal diagnosis of bronchiectasis (ICD10 J47), excluding cystic fibrosis, and length of stay <90 days were analysed by age, sex, ethnicity, socioeconomic deprivation, DHB, re-admissions and seasonality.

RESULTS

There were 5,494 admissions with a mean annual rate of 25.7 (age adjusted rate 20.4) per 100,000. Admission rates peaked in childhood and in the elderly, and increased steeply with socioeconomic deprivation. Age-adjusted rates were 38% higher for women, 4.9-fold higher for Māori and 9.1-fold higher for Pacific peoples. Counties Manukau had the highest unadjusted rate for any DHB (49.4 per 100,000). The overall 30 day readmission rate was 12.4%. Admissions peaked in winter and spring. The estimated cost in financial year 2012/13 was NZD 5.34M.

CONCLUSION

Hospital admissions for bronchiectasis are concentrated in socioeconomically disadvantaged young and elderly Māori and Pacific peoples; are more common in winter and spring, and incur a high annual cost. Evidence-based interventions to reduce the disproportionate burden of bronchiectasis in Māori and Pacific children and the elderly is a public health priority.

Azithromycin for Indigenous children with bronchiectasis: study protocol for a multi-centre randomized controlled trial

BACKGROUND

The prevalence of chronic suppurative lung disease (CSLD) and bronchiectasis unrelated to cystic fibrosis (CF) among Indigenous children in Australia, New Zealand and Alaska is very high. Antibiotics are a major component of treatment and are used both on a short or long-term basis. One aim of long-term or maintenance antibiotics is to reduce the frequency of acute pulmonary exacerbations and symptoms. However, there are few studies investigating the efficacy of long-term antibiotic use for CSLD and non-CF bronchiectasis among children. This study tests the hypothesis that azithromycin administered once a week as maintenance antibiotic treatment will reduce the rate of pulmonary exacerbations in Indigenous children with bronchiectasis.

METHODS/DESIGN

We are conducting a multicentre, randomised, double-blind, placebo controlled clinical trial in Australia and New Zealand. Inclusion criteria are: Aboriginal, Torres Strait Islander, Maori or Pacific Island children aged 1 to 8 years, diagnosed with bronchiectasis (or probable bronchiectasis) with no underlying disease identified (such as CF or primary immunodeficiency), and having had at least one episode of pulmonary exacerbation in the last 12 months. After informed consent, children are randomised to receive either azithromycin (30 mg/kg once a week) or placebo (once a week) for 12-24 months from study entry. Primary outcomes are the rate of pulmonary exacerbations and time to pulmonary exacerbation determined by review of patient medical records. Secondary outcomes include length and severity of pulmonary exacerbation episodes, changes in growth, school loss, respiratory symptoms, forced expiratory volume in 1-second (FEV(1); for children ≥6 years), and sputum characteristics. Safety endpoints include serious adverse events. Antibiotic resistance in respiratory bacterial pathogens colonising the nasopharynx is monitored. Data derived from medical records and clinical assessments every 3 to 4 months for up to 24 months from study entry are recorded on standardised forms.

DISCUSSION

Should this trial demonstrate that azithromycin is efficacious in reducing the number of pulmonary exacerbations, it will provide a much-needed rationale for the use of long-term antibiotics in the medical management of bronchiectasis in Indigenous children.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12610000383066.

Major haemoptysis in Hong Kong: aetiologies, angiographic findings and outcomes of bronchial artery embolisation

SETTING

Tertiary referral centres.

OBJECTIVE

To provide comprehensive updates on the aetiologies, angiographic findings and outcomes of bronchial artery embolisation (BAE) for life-threatening haemoptysis in Hong Kong.

DESIGN

Retrospective review of clinical records of consecutive patients presenting with life-threatening haemoptysis from 2000 to 2006.

RESULTS

There were 3006 admissions due to haemoptysis involving 2260 patients during the study period; of these, 251 patients had life-threatening haemoptysis. Pulmonary tuberculosis (PTB) (active or inactive) and bronchiectasis were the main underlying causes. BAE was attempted in 167 patients. There was a high prevalence of bilateral bronchial arterial abnormalities (31.7%), presence of abnormal non-bronchial arteries (41.3%) and presence of broncho-pulmonary shunt (38.9%). BAE had a high immediate success rate of 95.7%, with a 5-year recurrence rate of 45.0%. Recurrent life-threatening haemoptysis was independently associated with past history of haemoptysis (P = 0.024), presence of broncho-pulmonary shunt (P = 0.013), and incomplete embolisation (P = 0.002). Complications were uncommon (<5%) and self-limiting.

CONCLUSIONS

In Hong Kong, about one tenth of admissions due to haemoptysis were life-threatening. PTB and bronchiectasis were the major causes. Complications due to BAE were uncommon and self-limiting, with super-selective catheters.

Lack of association between matrix metalloproteinase 8 promoter polymorphism and bronchiectasis in Koreans

The observation that human matrix metalloproteinase (MMP)-8 is over-expressed in ectatic bronchi in patients with bronchiectasis suggests that polymorphisms altering the expression of MMP-8 may contribute to the susceptibility to development of bronchiectasis. We evaluated the association between the presence of bronchiectasis in a Korean population and two single nucleotide polymorphisms (SNPs) (-799C/ T and -381A/G) on the promoter region of the MMP-8 gene that are reported to alter the promoter activity and thereby the gene expression. Genotyping through polymerase chain reaction (PCR) and subsequent automatic sequencing was done in 167 patients with bronchiectasis and their age-, sex-matched healthy controls to reveal that only -799C/T is polymorphic among Koreans. In the patient group with bronchiectasis, the frequency of -799C/C, C/T, and T/T genotypes were 41.9%, 49.7%, and 8.4%, respectively. A similar distribution was observed in the control group: C/C (49.7%), C/T (43.1%), and T/T (7.2%) (p=0.36). In subgroup analysis, no significant difference was observed among the patients according to; the extent of disease (p=0.76), colonization of microorganisms (p=0.56), or association of mycobacteria (p=0.17). From these results, we conclude that -799C/T on the promoter region of MMP-8 lacks association with development of bronchiectasis in Koreans.

Hospital-based case-control study of bronchiectasis in indigenous children in Central Australia

BACKGROUND

Childhood pneumonia has been reported to be associated with the development of bronchiectasis but there are no case-control studies that have examined this. This study examined the relationship between hospital admission for episode(s) of pneumonia and the risk of radiologically proven bronchiectasis.

METHODS

A medical record-based case-control study of bronchiectasis in Indigenous children was conducted in Central Australia. Controls (183), matched to cases (61) by gender, age and year of diagnosis, were Indigenous children hospitalized with other conditions.

RESULTS

There was a strong association between a history of hospitalized pneumonia and bronchiectasis [odds ratio (OR), 15.2; 95% confidence interval (95% CI) 4.4-52.7]. This was particularly evident in recurrent hospitalized pneumonia (P for trend < 0.01), severe pneumonia episodes with longer hospital stay (P for trend < 0.01), presence of atelectasis (OR 11.9; 95% CI 3.1-45.9) and requirement for oxygen (P for trend < 0.01). The overall number of pneumonia episodes, rather than its site, was associated with bronchiectasis. Although the total number of pneumonia episodes in the first year of life did not increase the risk of bronchiectasis, more severe episodes early in life did. Malnutrition, premature birth and being small for gestational age were more common findings among cases. Breast-feeding appeared to be a protective factor (OR 0.2; 95% CI 0.1-0.7).

CONCLUSIONS

Although we cannot fully answer the question of why bronchiectasis is much more common in Indigenous children, we have provided strong evidence of an association between bronchiectasis and severe and recurrent pneumonia episodes in infancy and childhood.

Retrospective review of children presenting with non cystic fibrosis bronchiectasis: HRCT features and clinical relationships

Non cystic fibrosis (CF) bronchiectasis in children presents with a spectrum of disease severity. Our aims were to document the extent and severity of disease in children with non-CF bronchiectasis, to review the inter- and intraobserver agreement for the high-resolution computed tomography (HRCT) features examined, and to assess correlations between HRCT features and clinical measures of severity. We performed a retrospective review of 56 children from the Starship Children's Hospital. HRCT scans were scored by a modified Bhalla system, and the chest X-rays using the Brasfield score. Scores were correlated with demographics, number of hospitalizations, disease duration, pulmonary function, clinical examination, and chronic sputum infection. The bronchiectasis seen was widespread and severe, particularly in Maori and Pacific Island children. The kappa coefficient for intraobserver agreement was better than that for interobserver agreement. Comparisons between HRCT scan and lung function parameters showed that the strongest relationships were between forced expiratory volume in 1 sec (FEV(1)) and forced expiratory flow between 25-75% of forced vital capacity (FEF(25-75)) with the extent of bronchiectasis, bronchial wall thickening, and air trapping. Children with digital clubbing and chest deformity showed significantly higher scores for extent of bronchiectasis, bronchial wall dilatation and thickness, and overall computed tomography (CT) score. No relationship was demonstrated between chronic sputum infection and CT score. The HRCT score demonstrated a stronger correlation between the extent and severity of bronchiectasis, and spirometry values, than the chest X-ray score. In conclusion, pediatric non-CF bronchiectasis in Auckland is extensive and severe. The good intraobserver ratings mean that consistency of scoring is possible on repeated scans. This study cannot comment on the relationships of CT and less severe disease.

The effect of Pseudomonas aeruginosa infection on clinical parameters in steady-state bronchiectasis

STUDY OBJECTIVE

To investigate the effect of Pseudomonas aeruginosa infection on clinical parameters in Chinese patients with noncystic fibrosis and steady-state bronchiectasis.

DESIGN

Prospective, cross-sectional clinicomicrobiological study with informed consent.

SETTING

Consecutive outpatient recruitment from a specialist bronchiectasis respiratory clinic.

PATIENTS

Outpatients (n = 100; 62 women; 55.1+/-16.7 years old; FEV1/FVC 1.4+/-0.7/2.1+/-0.9 L), who had stable respiratory symptoms for more than 3 weeks.

MEASUREMENTS AND RESULTS

Respiratory pathogens isolated from the sputum were: Pseudomonas aeruginosa (33), Haemophilus influenzae (10), Moraxella catarrhalis (2), other Gram-negative bacilli (5), Streptococcus pneumoniae (6), Staphylococcus aureus (5), mycobacteria (3), and yeast (1). Clinical parameters in patients with positive isolation of P aeruginosa were compared with those without the organism in the sputum culture (non-P aeruginosa). In the P aeruginosa group, the FEV1/FVC ratio and sputum volume were lower (p < 0.005) and higher (p < 0.0001), respectively, than those of the non-P aeruginosa group. The FEV1/FVC ratio (< 60%) and sputum volume (grading > 5) were independently associated with a positive sputum isolation of P aeruginosa with odds ratios of 3.1 (confidence interval [CI] 1.2 to 8.4; p < 0.01) and 4.7 (CI 1.6 to 13.3; p < 0.001), respectively.

CONCLUSIONS

P aeruginosa is the predominant respiratory pathogen isolated in the sputum of Chinese patients with steady-state bronchiectasis, and its isolation is associated with high sputum output (> or = 75th quartile) and moderately severe airflow obstruction (FEV1/FVC < 60%).