HRCT lung abnormalities are not a surrogate for exercise limitation in bronchiectasis

Abstract

In paediatric bronchiectasis, there has been limited work on the relationship between disease severity as assessed by exercise limitation and high resolution computed tomography (HRCT).An observational study was performed on 36 children who completed a questionnaire, physical examination, spirometry and sputum analysis, followed by a low dose of radiation protocol chest computed tomography (CT) scan and cycle ergometry incremental exercise test. A modified Bhalla score was used to score the HRCT abnormalities. The exercise variables used to assess functional status were heart rate, oxygen consumption, oxygen saturations and time of exercise. The results were compared with established normal paediatric values.The median (range) age of the children was 13 yrs (10.6-17.1). Age, sex, height, weight or pubertal status were equally distributed between the children with cystic fibrosis (CF) or non-CF bronchiectasis. The children with non-CF bronchiectasis had a lower median forced expiratory volume in one second % predicted than the children with CF (69% versus 76%, respectively). The distribution of lung disease differed between the two groups. The children with CF bronchiectasis had predominantly right upper lobe disease, and scored higher for the presence and extent of bronchiectasis. Otherwise, there was no statistical difference in the overall CT score or the individual CT parameters between the groups. There was evidence of exercise limitation in both CF and non-CF bronchiectasis compared to normal children. No consistent relationships were identified between the lung function parameters, HRCT findings or exercise parameters in either disease group.In this study, high resolution computed tomography features were not found to be markers of exercise capacity. As spirometry, high resolution computed tomography features and exercise testing give different information in children with cystic fibrosis and non-cystic fibrosis bronchiectasis, the current authors suggest all three may be required for the comprehensive assessment of respiratory status.

Is Lung Clearance Index (LCI) Affected by the Severity of Lung Disease in CF?

“…A lot of studies have suggested that LCI has the advantage over FEV 1 to detect CF lung disease in earlier stages [21,36,38,[64][65][66][67][68]. A more sophisticated analysis of the SnIII has revealed the Scond and Sacin, as indices to detect the mechanisms of ventilation inhomogeneity and the location of the different ventilated lung units.…”

Non-CF bronchiectasis: does knowing the aetiology lead to changes in management?

“…First, the data were collected at a single time point and no longitudinal findings could be used for comparison; therefore, the current authors were not able to comment on the progression of the radiological abnormalities and disease course. In addition, repeat CT would entail extra radiology, and recent evidence suggested CT abnormalities to be poor markers of exercise capacity and functional status [34]. Secondly, the patients were a selected group and there was a possibility of referral bias given the special interests of the two tertiary units: immunology (Great Ormond Street Hospital for Children), and PCD (Royal Brompton Hospital).…”

British Thoracic Society guideline for non-CFbronchiectasis

“…Exertional breathlessness is described in many case series 42 53 212 213 228. Children may also present with failure to thrive or malnutrition,53 212 213 although in the UK they are likely to be of normal weight and height 231. Less frequently described as presenting features are fever,228 chest pain228 and recurrent lower respiratory tract infection.…”