[Low-dose CT-guided transthoracic lung biopsy for evaluation of non-infectious chronic interstitial lung disease in children].

BACKGROUND

Children with interstitial pneumonitis (IP) of unknown origin often have to undergo open lung biopsy to establish a final diagnosis. Open lung biopsy is an invasive procedure with major potential complications. In the meantime, CT-guided transthoracic lung biopsy (TLB) has become a common diagnostic procedure in adults.

OBJECTIVE

The aim of this study was to retrospectively evaluate the efficacy and radiation exposure of low-dose CT-guided TLB in children with non-infectious IP of unknown origin.

METHODS

Twelve children (7-males, age range: 7 months-15 years) with non-infectious IP of unknown origin and inconclusive clinical tests underwent CT-guided TLB with a 20-gauge biopsy instrument. A low-dose protocol with acquisition of single slices was used on a 16-row CT scanner: 80 kVp, 20 mAs, slice thickness 10 mm. Biopsy specimens were processed by standard histopathological and immunohistochemical techniques and effective doses were individually calculated.

RESULTS

All biopsies were performed without major complications. Two children (17 %) developed a small pneumothorax/pulmonary haemorrhage that resolved spontaneously. A final diagnosis could be established in 9/12 patients (75 %) by CT-guided TLB. In 2 patients (17 %) the results of TLB were inconclusive; however, the clinical suspicion could be disproved. Open lung biopsy was performed in 1 patient (8 %), which demonstrated idiopathic pulmonary fibrosis. On average, the effective dose of CT-guided TLB was 0.78 mSv (0.4 - 1.1 mSv).

CONCLUSION

Low-dose CT-guided TLB can be a helpful method for investigating children with non-infectious IP of unknown origin thus making open lung biopsy unnecessary. Application of a low-dose protocol leads to a significant reduction of radiation exposure in CT-guided TLB.