Abstract

Study Objectives: To assess the major difficulties in applying the updated classification on idiopathic interstitial pneumonia patterns and to define the minor features of each category in our patient population.

Design:

Retrospective study on cases who have been diagnosed as interstitial pneumonia/fibrosis.

Setting:

Our study group comprised 18 thoracoscopic or open lung wedge biopsy specimens,! lobectomy specimen, and 6 consultation cases.

Interventions:

According to the revised criteria on the histologic pattern analysis we subclassified cases into usual interstitial pneumonia (UIP), desquamative interstitial pneumonia (DIP), acute interstitial pneumonia (AIP), bronchiolitis obliterans organizing pneumonia (BOOP), respiratory bronchiolitis associated lung disease (RB-ILD), and nonspesific interstitial pneumonia (NSIP) patterns. In all of these pattern groups we determined the minor histological features. In addition, we tried to ascertain if there is any difference in the fibroblastic foci between BOOP, NSIP, and UIP in terms of new capillary formation.

Results:

The distribution of cases according to histologic pattern analysis was as follows: NSIP- cellular= 3, NSIP- fibrosing= 5, AIP= 2, BOOP= 4, UIP= 8, and RB-ILD=3.

Conclusions:

Our study revealed that, with a systematic approach to the lung biopsy, vast majority of the idiopathic interstitial pneumonia (IIP) cases could be classified into patterns with prognostic implications.