Idiopathic lymphocytic pleuritis: radiographic and high-resolution CT appearances and changes in response to therapy in two adults.

Inflammatory conditions of the pleura characterized by a predominantly lymphocytic infiltrate are described in several disorders. The commonest underlying aetiologies include tuberculous infection, autoimmune disorders (particularly Sjogren's syndrome), and post coronary artery bypass graft surgery. Idiopathic lymphocytic pleuritis (ILP) is a rare form of diffuse pleural inflammation characterized by extensive lymphocytic infiltration for which no cause is found. Radiological descriptions of ILP are limited. We describe the radiographic and high-resolution computed tomography (HRCT) imaging features and response to corticosteroid therapy of ILP in two adults. Both patients presented with bilateral diffuse pleural thickening of >10 mm thickness extending >10 cm craniocaudally with small focal areas of atelectasis. Both cases demonstrated marked improvement in the degree and extent of pleural thickening and rounded atelectasis following corticosteroid therapy. HRCT provided a useful noninvasive method of assessing disease response to therapy.