Can computed tomography and carbon monoxide transfer coefficient diagnose an asthma-like phenotype in COPD?

BACKGROUND AND OBJECTIVE: Post-mortem and computed tomography (CT) studies indicated that emphysema is a feature of COPD even in the 'blue bloater/chronic bronchitis' type. We aim to test the hypothesis that the non-emphysematous patients are distinct from the main body of COPD and are more akin to asthmatic patients. METHODS: We studied 54 patients with COPD. Emphysema was measured by Goddard's visual scoring of CT scan and the carbon monoxide transfer coefficient (KCO). Bronchial biopsy was offered for thickness of basement membrane (BM) (≥7 µm) as a marker of remodelling in irreversible asthma. Spirometry was repeated after therapy with Budesonide/Formoterol for 1 year. RESULTS: The non-emphysematous phenotype were 24 of 54 patients (44%) by CT scan and 23 of 54 patients (43%) by KCO, showing agreement in 53 out of 54 patients. The non-emphysematous patients were younger, had higher forced expiratory volume in 1 s (FEV1 ) (median 61% vs 49.7%), greater prevalence of hypertrophy of nasal turbinates and higher serum IgE. The emphysematous phenotype had lower BMI and greater dyspnoea score. The BM was thickened in 11 of 14 and 0 of 10 patients in the non-emphysematous and emphysematous groups, respectively. Three patients without emphysema and a normal BM normalized their FEV1 upon receiving inhaled corticosteroid (ICS)/long-acting ß2 agonist (LABA). All the non-emphysematous improved their FEV1 after ICS/LABA (median = 215 mL). The median decline in the emphysematous was -65 mL. CONCLUSION: The non-emphysematous phenotype of COPD displays important features of asthma: clinical picture, histology and response to ICS. CT and KCO can predict spirometric response to ICS/LABA.

Abrupt withdrawal of inhaled corticosteroids does not result in spirometric deterioration in chronic obstructive pulmonary disease: Effect of phenotyping?

BACKGROUND AND OBJECTIVE: Some studies show a decline of FEV(1) only one month after withdrawal of inhaled corticosteroids (ICS), while others show no decline. We speculate that the presence of an asthma phenotype in the Chronic Obstructive Pulmonary Disease (COPD) population, and that its exclusion may result in no spirometric deterioration. METHODS: We performed a prospective clinical observation study on 32 patients who fulfilled the Global Initiative for Chronic Obstructive lung disease definition of COPD (Grade II-IV). They were divided into two phenotypic groups. 1. Irreversible asthma (A and B) (n = 13): A. Asthma: Bronchial biopsy shows diffuse thickening of basement membrane (≥ 6.6 µm). B. Airflow limitation (AFL) likely to be asthma: KCO > 80% predicted if the patient refused biopsy. 2. COPD (A and B) (n = 19): A. COPD: hypercapneic respiratory failure with raised bicarbonate, panlobular emphysema with multiple bullas, or bronchial biopsy showing squamous metaplasia and epithelial/subepithelial inflammation without thickening of the basement membrane. B. AFL likely to be COPD: KCO < 80% predicted. RESULTS: The asthma phenotype was significantly younger, had a strong association with hypertrophy of nasal turbinates, and registered a significant improvement of FEV(1) (350 ml) vs a decline of - 26.5 ml in the COPD phenotype following therapy with budesonide/formoterol for one year. Withdrawal of budesonide for 4 weeks in the COPD phenotype resulted in FEV(1) + 1.33% (SD ± 5.71) and FVC + 1.24% (SD ± 5.32); a change of <12% in all patients. CONCLUSIONS: We recorded no spirometric deterioration after exclusion of the asthma phenotype from a COPD group.

Comparison of three groups of patients with usual interstitial pneumonia.

OBJECTIVE: To determine the clinical characteristics and outcomes of patients with lungdominant connective tissue disease (LD-CTD) with a usual interstitial pneumonia (UIP) who do not meet the criteria for any form of CTD, and to compare these parameters with those of patients with idiopathic pulmonary fibrosis (IPF/UIP) and CTD-associated-UIP. METHODS: We conducted a prospective study on 118 patients diagnosed with UIP [LD-CTD, n = 28; CTDUIP, n = 29; and IPF/UIP, n = 61]. We compared the clinical characteristics, physiological findings, serum albumin concentrations, high-resolution computed tomography (HRCT) imaging data, and outcomes among the three groups and used Cox's proportional hazards regression analysis to identify variables associated with an increased risk of death. RESULTS: The LD-CTD and CTD-UIP patients were younger, more often female, and predominantly nonsmokers, compared with the IPF/UIP group. A significant difference in survival was evident between patients in the CTD-UIP and IPF/UIP groups (p = 0.028), but not between LD-CTD and IPF/UIP (p = 0.164) or between LD-CTD and CTD-UIP (p = 0.254). The variables associated with poorer survival in all UIP patients were (reduced) initial SpO2 level (hazard ratio [HR], 2.89; 95% confidence interval [CI] 2.1-3.7; p = 0.009) and lower serum albumin concentration (HR 2.16; 95% CI 1.6-2.7; p = 0.008). CONCLUSIONS: LD-CTD has distinct clinical characteristics that suggest an autoimmune background resembling that of CTD-UIP but differing from that of IPF/UIP. However, LD-CTD with a UIP pattern was not associated with improved survival. The resting oxygen saturation level and serum albumin concentration were independent predictors of mortality in all of the studied UIP patients, regardless of UIP type.

Asthma masquerading as chronic obstructive pulmonary disease: a study of smokers fulfilling the GOLD definition of chronic obstructive pulmonary disease.

BACKGROUND: Irreversible airways obstruction in smokers is usually attributed to chronic obstructive pulmonary disease (COPD). We speculate that some of these are cases of asthma indistinguishable from COPD. OBJECTIVES: To determine the prevalence of asthma in a 'COPD' population and how to differentiate the two conditions. METHODS: This was a prospective observational study of smokers fulfilling the Global Initiative for Chronic Obstructive Lung Disease definition of COPD [mean post-salbutamol forced expiratory volume in 1 s (FEV1) 66.9% predicted]. They were classified into 4 groups, as follows: (1) inhaled corticosteroid (ICS)-responsive asthma, defined by normalization of spirometry upon ICS treatment; (2) irreversible asthma, defined as airway obstruction for 1 year and bronchial biopsy indicating asthma; (3) COPD, in the presence of bilateral panlobular emphysema with bullae on high-resolution computed tomography, hypercapneic respiratory failure or bronchial biopsy indicating COPD, and (4) unclassified airflow limitation (AFL). RESULTS: Eighty patients fulfilled the definition of COPD. The initial diagnosis was COPD in 57.5% and asthma in 42.5%. The final diagnosis was ICS-responsive asthma in 48 patients (60%), irreversible asthma in 8 (10%), COPD in 16 (20%) and unclassified AFL in 8 (10%). A normal transfer coefficient for carbon monoxide (KCO) and an FEV1 fluctuation ≥18% during 1 year of follow-up distinguished irreversible asthma and COPD. Seven of the 8 patients with irreversible asthma had improved FEV1 at the end of 1 year (median 320 ml compared with -29 ml in COPD). Five out of the 8 unclassified AFL cases had normal KCO and a large improvement in FEV(1) suggestive of irreversible asthma. CONCLUSIONS: COPD, even in heavy smokers, includes cases of asthma. FEV1 fluctuation during 1 year is a novel concept which may distinguish irreversible asthma and COPD.

Yield and complications of flexible fiberoptic bronchoscopy in a teaching hospital.

OBJECTIVE: To assess the diagnostic yield and safety of flexible fiberoptic bronchoscopy (FFB). METHODS: A retrospective review of bronchoscopy reports and corresponding patients charts over 3 years from January 2004 - December 2006 in King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia. Indication for procedure, suspected diagnosis, final diagnosis, and complications were reported. RESULTS: Out of 720 patients, 707 (98.2%) patients had a full follow up. Five hundred and ninety-two (83.7%) underwent FFB for diagnostic purposes and 115 (16.3%) for therapeutic purposes. The mean age was 42 -/+ 18 years. Infection, including mycobacterium tuberculosis, and malignancy were the 2 main indications for FFB (35.9% and 25.9%). The overall diagnostic yield was 58%. Tuberculosis was diagnosed in 67% of suspected cases, whereas bacterial pneumonia was diagnosed in 40.5%. Malignancy was confirmed in 61.2% of suspected cases. Bronchoscopy diagnosed 37 (43%) of 86 patients with interstitial lung disease. The diagnostic yield was 57% for sarcoidosis, 40% for usual interstitial pneumonia and 88% for bronchiolitis obliterans organizing pneumonia. The overall complication rate was 5%; pneumothorax occurred in 0.56% and was associated exclusively with transbronchial biopsy. No mortality was observed. CONCLUSION: Flexible fiberoptic bronchoscopy is a useful diagnostic tool with a low rate of complications. The diagnostic yield in our institution is similar to that reported in Western series.