Extrinsic allergic alveolitis: comparative study of the bronchoalveolar lavage profiles and radiological presentation

Bronchoalveolar Lavage Fluid Cellular Analysis and Radiologic Patterns in Patients With Fibrotic Interstitial Lung Disease

BACKGROUND

Bronchoalveolar lavage (BAL) cellular analysis is often recommended during the initial diagnostic evaluation of fibrotic interstitial lung disease (ILD). Despite recommendation for its use, between-center heterogeneity exists and supportive data concerning the clinical utility and correlation of BAL findings with radiologic features or patterns remain sparse.

RESEARCH QUESTION

In patients with fibrotic ILD, are BAL findings associated with radiologic features, patterns, and clinical diagnoses?

STUDY DESIGN AND METHODS

Patients with fibrotic ILD who underwent BAL for diagnostic evaluation and who were enrolled in the prospective Canadian Registry for Pulmonary Fibrosis were re-reviewed in a standardized multidisciplinary discussion (MDD). BAL was categorized according to guideline-recommended thresholds, and using thresholds of lymphocytosis > 20% and neutrophils > 4.5%. High-resolution CT (HRCT) scans were scored (blinded to clinical data) for specific features and percentage lung involvement. Radiologists classified HRCT scans according to guideline-defined patterns for idiopathic pulmonary fibrosis and fibrotic hypersensitivity pneumonitis (fHP); then, MDD diagnoses were assigned, considering all available data.

RESULTS

Bronchoscopy with cellular analysis was performed in 209 of 1,593 patients (13%). Lymphocyte % was weakly negatively correlated with total fibrosis % (r = -0.16, P = .023) but not statistically significantly correlated with ground glass opacity % (r = 0.01, P = .94). A mixed BAL pattern was the most frequent in all radiologic patterns (range, 45%-69%), with a minority classifiable according to BAL guidelines. BAL lymphocytosis appeared with similar frequency across HRCT patterns of fHP (21%) and usual interstitial pneumonia (18%). Only 5% of patients with MDD-based fHP had a guideline-defined isolated lymphocytosis > 15%.

INTERPRETATION

BAL cellular analyses did not significantly correlate with radiologic features, guideline patterns, or MDD-based diagnoses. Ground glass opacities are often interpreted to represent pulmonary inflammation, but were not associated with BAL lymphocytosis in this cohort.

Transbronchial biopsy in chronic hypersensitivity pneumonitis

Introduction

The diagnosis of chronic hypersensitivity pneumonitis (CHP) is based on relevant exposure, tomographic findings and, in some cases, pathological data. The role of bronchoscopy is uncertain, especially in the fibrotic form of CHP.

Aim

To analyze the yield of transbronchial biopsy (TBBx) in patients with CHP according to tomographic findings and to evaluate the importance of bronchoalveolar lavage (BAL) in the diagnostic approach.

Methods

This retrospective study analyzed patients with CHP who underwent TBBx in São Paulo, Brazil. The TBBx findings were classified as characteristic (granulomas and/or multinucleated giant cells, associated or not with peribronchiolar infiltration of lymphocytes and plasma cells and bronchiolocentric distribution) and supportive (data indicative of small airway injury: peribronchiolar metaplasia, organizing pneumonia, and intra-alveolar foamy macrophages).

Results

One hundred nine patients were included. The presence of characteristic findings of HP was seen in 16 patients (14.7%), and supportive findings were seen in 32 patients (29.4%), with a total yield of 44%. Pathological characteristic findings were more common in cases without fibrosis on high-resolution computed tomography (HRCT) (27.3% vs. 9.2%, p= 0.014), whereas the presence of supportive findings was more common in fibrotic HP (38.1% vs. 9.1%, p= 0.002). Fifty-two patients had differential cytology in BAL fluid. Lymphocytosis (> 20%) was present in 51.9% of the patients. There was no difference in the median lymphocyte count according to nonfibrotic and fibrotic tomographic findings on HRCT.

Conclusion

TBBx and BAL fluid cytology have a role in CHP diagnosis.

Long term radiological features of radiation-induced lung damage

PURPOSE

To describe the radiological findings of radiation-induced lung damage (RILD) present on CT imaging of lung cancer patients 12 months after radical chemoradiation.

MATERIAL AND METHODS

Baseline and 12-month CT scans of 33 patients were reviewed from a phase I/II clinical trial of isotoxic chemoradiation (IDEAL CRT). CT findings were scored in three categories derived from eleven sub-categories: (1) parenchymal change, defined as the presence of consolidation, ground-glass opacities (GGOs), traction bronchiectasis and/or reticulation; (2) lung volume reduction, identified through reduction in lung height and/or distortions in fissures, diaphragm, anterior junction line and major airways anatomy, and (3) pleural changes, either thickening and/or effusion.

RESULTS

Six patients were excluded from the analysis due to anatomical changes caused by partial lung collapse and abscess. All remaining 27 patients had radiological evidence of lung damage. The three categories, parenchymal change, shrinkage and pleural change were present in 100%, 96% and 82% respectively. All patients had at least two categories of change present and 72% all three. GGOs, reticulation and traction bronchiectasis were present in 44%, 52% and 37% of patients.

CONCLUSIONS

Parenchymal change, lung shrinkage and pleural change are present in a high proportion of patients and are frequently identified in RILD. GGOs, reticulation and traction bronchiectasis are common at 12 months but not diagnostic.

Scoring of the radiological picture of idiopathic interstitial pneumonia: a study to verify the reliability of the method

Background

Idiopathic pulmonary fibrosis (IPF) is a clinical form of usual interstitial pneumonia (UIP). Computed chest tomography (CT) has a fundamental role in the multidisciplinary diagnostics. However, it has not been verified if and how a subjective opinion of a radiologists or pneumologists can influence the assessment and overall diagnostic summary.

Purpose

To verify the reliability of the scoring system.

Material and Methods

Assessment of conformity of the radiological score of high-resolution CT (HRCT) of lungs in patients with IPF was performed by a group of radiologists and pneumologists. Personal data were blinded and the assessment was performed independently using the Dutka/Vasakova scoring system (modification of the Gay system). The final score of the single assessors was then evaluated by means of the paired Spearman’s correlation and analysis of the principal components.

Results

Two principal components explaining cumulatively a 62% or 73% variability of the assessment of the single assessors were extracted during the analysis. The groups did not differ both in terms of specialty and experience with the assessment of the HRCT findings.

Conclusion

According to our study, scoring of a radiological image using the Dutka/Vasakova system is a reliable method in the hands of experienced radiologists. Significant differences occur during the assessment performed by pneumologists especially during the evaluation of the alveolar changes.

An official American Thoracic Society clinical practice guideline: the clinical utility of bronchoalveolar lavage cellular analysis in interstitial lung disease

BACKGROUND

The clinical utility of bronchoalveolar lavage fluid (BAL) cell analysis for the diagnosis and management of patients with interstitial lung disease (ILD) has been a subject of debate and controversy. The American Thoracic Society (ATS) sponsored a committee of international experts to examine all relevant literature on BAL in ILD and provide recommendations concerning the use of BAL in the diagnosis and management of patients with suspected ILD.

PURPOSE

To provide recommendations for (1) the performance and processing of BAL and (2) the interpretation of BAL nucleated immune cell patterns and other BAL characteristics in patients with suspected ILD.

METHODS

A pragmatic systematic review was performed to identify unique citations related to BAL in patients with ILD that were published between 1970 and 2006. The search was updated during the guideline development process to include published literature through March 2011. This is the evidence upon which the committee's conclusions and recommendations are based.

RESULTS

Recommendations for the performance and processing of BAL, as well as the interpretation of BAL findings, were formulated by the committee.

CONCLUSIONS

When used in conjunction with comprehensive clinical information and adequate thoracic imaging such as high-resolution computed tomography of the thorax, BAL cell patterns and other characteristics frequently provide useful information for the diagnostic evaluation of patients with suspected ILD.