Higher serum levels of periostin and the risk of exacerbations in moderate asthmatics.

BACKGROUND: In asthma, exacerbations and poor disease control are linked to airway allergic inflammation. Serum periostin has been proposed as a systemic biomarker of eosinophilic inflammation. This pilot study aims at evaluating whether in patients with moderate asthma, higher baseline levels of serum periostin are associated with a greater risk of exacerbation. METHODS: Fifteen outpatients with moderate allergic asthma were recruited. Serum concentrations of periostin were assessed (ELISA) at baseline, and the frequency of asthma exacerbations was recorded during a one-year follow-up. RESULTS: Patients (M/F: 10/5, mean age of 47.6 ± 11.0 years) had mean ACQ score of 5.5 ± 4.2 and FEV1%pred of 81.9 ± 21.7 %. Baseline serum levels of periostin did not correlate with lung function parameters, nor with the ACQ score (p ≥0.05 for all analyses). Five subjects (33 % of the study group) reported one or more exacerbations during the following year. Baseline serum levels of periostin were significantly higher in subjects who experienced one or more exacerbations during the one year period of follow-up, compared with subjects with no exacerbations: median serum periostin level was 4047 ng/ml (range: 2231 to 4889 ng/ml) and 222 ng/ml (range 28.2 to 1631 ng/ml) respectively; p = 0.001. CONCLUSION: The findings of the present pilot study could form the basis for the design of larger studies aiming at developing strategies to identify asthmatic patients at risk for exacerbations.

Early lung function abnormalities in acromegaly.

BACKGROUND: Acromegaly is an insidious disorder caused by a pituitary growth hormone (GH)-secreting adenoma resulting in high circulating levels of GH and insulin-like growth factor I (IGF-I). Respiratory disorders are common complications in acromegaly, and can severely impact on quality of life, eventually affecting mortality. OBJECTIVES: The present study aimed to explore structural and functional lung alterations of acromegalic subjects. METHODS: We enrolled 10 consecutive patients (M/F: 5/5) affected by acromegaly. In all patients, magnetic resonance imaging (MRI) revealed the presence of pituitary tumor. All patients underwent clinical, lung functional, biological, and radiological assessments. Ten healthy age-matched subjects also served as controls. RESULTS: No statistically significant differences in lung function were detected between acromegalic and healthy subjects (p ≥ 0.05 for all analyses). However, the diffusing capacity for CO (TLCO) was significantly lower in the acromegalic group than in healthy subjects (TLCO% predicted: 78.1 ± 16 vs. 90 ± 6 %, respectively, p = 0.04; KCO% predicted: 77 ± 16 vs. 93 ± 5 %, p = 0.02, respectively). None of the lung function parameters correlated with duration of the disease, or with inflammatory marker of the airways. In acromegalics, biological (exhaled NO concentrations) and imaging (total lung volume, TLV, and mean lung density, MLD) evaluations were within normal values. The TLV measured by HRCT was 3540 ± 1555 ml in acromegalics, and the MLD was -711 ± 73 HU. None of the lung functional, radiological, and biological findings correlated with GH or IGF-I levels, and no correlation was found with duration of disease. CONCLUSIONS: In the current study, lung function evaluation allowed to detect early involvement of lung parenchyma, as assessed by TLCO and KCO, even in the absence of parenchymal density alterations of the lung by HRCT. These findings suggest to routinely include the carbon monoxide diffusing capacity in the lung function assessment for an early intervention in acromegaly.

Validation of lung densitometry threshold at CT for the distinction between senile lung and emphysema in elderly subjects.

BACKGROUND AND AIMS: An ageing lung is characterised by distal airspace enlargement without alveolar wall destruction: therefore the anatomical distinction between senile lung and emphysema is clear-cut. In clinical settings the definition of precise boundaries between normalcy and pathology is more difficult with the risk of overdiagnosis. CT is an important diagnostic advancement in the field of COPD. Most methods for the evaluation of emphysema are based on the detection and measurement of areas characterised by a density level below a threshold assumed to characterize parenchymal destruction. METHODS: Our retrospective study included 47 healthy subjects (65-91 years), 36 never smokers and 11 former smokers. As a reference sample we recruited 9 patients with emphysema (69-81 years). Thoracic scan was performed by single slice spiral CT and acquired without contrast enhancement. For each scan and on both lungs we sampled eighteen regions of interest in the upper, middle and lower field. Mean lung density (MLD) and lower limit of normal (LLN) of density distribution were calculated. RESULTS: MLD for the whole study sample was -846 +/- 41 HU. -901 HU was the LLN of density distribution in the study sample. No significant correlation was noted between age and MLD. In the emphysematous sample the average lung density was -946 +/- 18 HU. The mean coefficient of variation was 3% in the healthy sample and 2% in the emphysematous one. The difference between groups was significant (p < 0.0001). In one healthy subject only we measured a value slightly below the threshold reported in literature for conventional CT; no emphysematous value fell above the LLN. CONCLUSIONS: This study highlights the fact that in the elderly the threshold level of lung density commonly adopted in diagnostic algorithms of emphysema is fully applicable. When applying this method to older subjects the risk of misinterpreting areas of physiologic non-destructive reduction of density as emphysema is low.