AB0475 Shrinking Lung Syndrome in Systemic Lupus Erythematosus – A Rare Complication

BackgroundPleuropulmonary involvement in Systemic Lupus Erythematosus (SLE) occurs in 60 to 80% of patients. Shrinking lung syndrome (SLS) is a non-exclusive, rare manifestation of SLE. The pathogenesis and treatment of SLS are not well established.ObjectivesWe describe the clinical, immunological and radiological features and the therapeutic management of a series of 8 cases of SLS.MethodsThis study is a retrospective, descriptive study of a series of 8 cases of patients diagnosed with SLE in the Rheumatology Unit of Ramόn y Cajal Hospital and Severo Ochoa Hospital.ResultsOf the 8 patients, 7 were women with a mean age at diagnosis of 40 years. Only 2 patients had severe visceral involvement. All patients had a history of serositis. All patients had positive ANA, 87.5% anti-DNA positive and 100% had low complement at some point in the evolution of the disease. 62.5% had anti-Ro and 50% had anti-RNP. 37.5% of patients were already in treated with low or intermediate doses of corticosteroids at the time of diagnosis, 37.5% received dolquine, 25% were treated with azathioprine and one patient had epratuzumab.In relation to diagnostic studies, 100% of patients had elevating one hemidiaphragm or both on chest radiography and basal atelactasis. The most common findings on the CT scan were: elevation of the diaphragm, pleural effusion and the presence of basal atelectasis. All cases had a restrictive pattern in PFT and in the cases in which the results were available, the carbon monoxide gas transfer capacity was reduced. Regarding the therapeutic management, 62.5% were treated initially with intermediate-high doses of oral corticosteroids (mean dose 17.5 mg/day), in 25% was added Chloroquine, in 25% of cases Azathioprine and MMF in one patient. Only one patient received treatment with Beta-2 agonists. The evolution was favorable only in the patient receiving MMF with clinical and radiological improvement of stabilization on clinical and radiological findings over the time. In 62.5% of patients the pleuritic chest pain persisted and 37.5% presented later infectious respiratory complications.ConclusionsSLS is a rare complication in patients with SLE. The pathogenesis of SLS is unknown. It was suggested the possible involvement of the anti-Ro antibody. In our series, 62.5% had anti-Ro positive and 50% anti-RNP positive. The SLS must be suspected when a SLE patient star with unexplained dyspnea and/or pleuritic chest pain and a loss of lung volume in the imaging st