Table 4

Pulmonary Lymphangiectasia: diagnostic work-up

Diagnostic test
Main features
Comment

Chest x-ray
Hyperinflation with interstitial markings
Radiological findings in PL may improve over time. Longitudinal follow-up pointed to the possible progression of hazy infiltrates, that are usually seen during the neonatal period, to a more perihilar interstitial pattern with varying degrees of lung inflation
High Resolution Computed Tomography (HRCT)
Diffuse thickening of the interstitium, both of the peribronchovascular interstitium and the septa surrounding the lobules
HRCT is the technique of choice for diagnosing PL
Magnetic Resonance Imaging (MRI)
Coronal MRI T1 may permit to show thickening of the interstitium, pleural fluid effusion, and atelectasia. Axial MRI T2 usually shows high-signal material within the pulmonary interstitium, which is very often associated with pleural effusion.
HRCT is better than MRI not only in diagnosing PL, but, more in geeral, for the diagnosis of pediatric interstitial lung disease.
Lung biopsy
Useful for demonstrating the presence of dilated lymphatic spaces in the sub-pleural connective tissue, along thickened interlobar septa, and around bronchovascular axes
Great caution must be taken when preparing histological specimens and when interpreting lung biopsies or autopy samples
Lymphoscintigraphy
Useful for evaluating lung lymph vessel involvement by showing radiotracer accumulation in the lung and by providing evidence of back-flow within the thoracic duct
It provides valuable morpho-functional information regarding the lymphatic system
Bronchoscopic evaluation and lung function tests
Not specific
They may be useful for ruling out other pulmonary pathologies and for carrying out bronchial lavage in order to identify and isolate respiratory pathogens

Bellini et al. Orphanet Journal of Rare Diseases 2006 1:43   doi:10.1186/1750-1172-1-43