Abstract

Background

Apart from surgical lung biopsy (SLB), transbronchial cryobiopsy (TCB) is an alternative diagnostic tool for tissue sampling in fibrosing interstitial lung disease (ILD). It is unclear whether the findings contribute substantially to a conclusive clinical diagnosis and whether SLB may represent an additional optional step up procedure.

Methods

Prospective trial in 61 consecutive fibrotic ILD subjects (25 female, 66±11 years, BMI 29±6 kg/m²) with the indication for lung tissue sampling. The rate of conclusive findings after TCB (i.e. sufficient clinical confidence after interdisciplinary case evaluation) and the impact of an additional SLB in case of inconclusive findings were determined. Complication rates before and after modification of the TCB procedure were analyzed.

Results

A conclusive clinical diagnosis could be elaborated in 44/61 subjects (72%) based on TCB results and in 12/13 subjects after additional SLB. In case of inconclusive findings after TCB, after SLB the histopathological diagnosis changed in 3 subjects (23%) and the diagnostic confidence improved in 6 subjects (46%). By modification of the TCB procedure complication rates could be reduced (pneumothorax from 26% to 12%, bleeding from 79% to 0%). 30-day-mortality was 2/61 subjects, deaths occurred due to ILD exacerbation and were potentially procedure-associated.

Conclusions

In fibrosing ILD, TCB contributes to a conclusive clinical diagnosis in about 70%. In case of inconclusive findings SLB remains an optional step up procedure leading to a conclusive diagnosis in nearly all cases. Modifications of the TCB procedure can reduce complication rates. There may be a relevant risk of procedure-associate exacerbations with potentially lethal outcome.