Fibred confocal fluorescence microscopy in the diagnosis of interstitial lung diseases.
BACKGROUND
Accurate diagnosis is critical to both therapeutic decisions and prognostication in interstitial lung diseases (ILD). However, surgical lung biopsies carry high complication rates. Fibred confocal fluorescence microscopy (FCFM) offers an alternative as it can visualize lung tissuein vivoat the cellular level with minimal adverse events. We wanted to investigate the diagnostic utility, and safety of using FCFM for patients with ILD.


METHODS
In patients with suspected ILD, FCFM images were obtained from multiple bronchopulmonary segments using a miniprobe inserted through the working channel of a flexible bronchoscope. The procedure was performed under moderate sedation in an outpatient setting. Morphometric measurements and fibre pattern analyses were co-related with computed tomography (CT) findings and patients' final diagnoses based on multi-disciplinary consensus.


RESULTS
One hundred and eighty four segments were imaged in 27 patients (18 males) with a median age of 67 years (range, 24-79 years). They were grouped into chronic fibrosing interstitial pneumonia (16 patients) and other ILDs. Six distinct FCFM patterns were observed: normal, increased fibres, densely packed fibres, hypercellular, thickened fibres and others/non-specific. The pattern resembling densely packed fibres was seen in at least one segment in 68.8% patients with chronic fibrosing interstitial pneumonia, but only 36.4% in other ILD (P=0.097). An association between inflammatory patterns on CT and a hypercellular pattern on FCFM was also found (P<0.001).


CONCLUSIONS
Our study shows the potential of FCFM in classifying ILD, but its role in further diagnosis remains limited.
Duke-NUS Medical School, Singapore, Singapore.
Peng
P
Meng
Department of Respiratory and Critical Care Medicine, Singapore General Hospital, Singapore, Singapore.
Gan Liang
GL
Tan
Duke-NUS Medical School, Singapore, Singapore;; Department of Respiratory and Critical Care Medicine, Singapore General Hospital, Singapore, Singapore.
Su Ying
SY
Low
Department of Pathology, Singapore General Hospital, Singapore, Singapore.
Angela
A
Takano
Department of Diagnostic Radiology, Singapore General Hospital, Singapore, Singapore.
Yuen Li
YL
Ng
Duke-NUS Medical School, Singapore, Singapore;; Department of Respiratory and Critical Care Medicine, Singapore General Hospital, Singapore, Singapore.
Devanand
D
Anantham
Fluorescence; confocal; idiopathic pulmonary fibrosis (IPF); interstitial; lung disease; microscopy