Shrinking lung syndrome in systemic lupus erythematosus

Abstract

Shrinking lung syndrome (SLS) is a rare and less known complication mainly associated with systemic lupus erythematosus (SLE). In this study, we analyze the clinical features, investigation findings, approaches to management, and outcome in a case series of 9 adult patients with SLE and SLS diagnosed during a 35-year period in 3 referral tertiary care hospitals in Spain. Additionally, we reviewed 80 additional cases previously reported (PubMed 1965–2015). These 80 cases, together with our 9 patients, form the basis of the present analysis.The overall SLS prevalence in our SLE population was 1.1% (9/829). SLS may complicate SLE at any time over its course, and it usually occurs in patients without previous or concomitant major organ involvement. More than half of the patients had inactive lupus according to SELENA-systemic lupus erythematosus disease activity index (SLEDAI) scores. Typically, it presents with progressive exertional dyspnea of variable severity, accompanied by pleuritic chest pain in 76% of the cases.An important diagnostic delay is common. The diagnostic tools that showed better yield for SLS detection are the imaging techniques (chest x-ray and high-resolution computed tomography) along with pulmonary and diaphragmatic function tests. Evaluation of diaphragm dome motion by M-mode ultrasonography and phrenic nerve conduction studies are less useful.There are no standardized guidelines for the treatment of SLS in SLE. The majority of patients were treated with medium or high doses of glucocorticoids. Several immunosuppressive agents have been used in conjunction with steroids either if the patient fails to improve or since the beginning of the treatment. Theophylline and beta-agonists, alone or in combination with glucocorticoids, have been suggested with the intent to increase diaphragmatic strength.The overall long-term prognosis was good. The great majority of patients had significant clinical improvement and stabilization, or mild to moderate improvement on pulmonary function tests. The mortality rate was very low.

Shrinking Lung Syndrome – A rare cause of recurrent dyspnoea in SLE

“…The prevalence of SLS varies according to different studies. The most recent review in 2016 reported only 1.1% cases of SLS (9 of 829 SLE) over 35 years from three rheumatology referral centres in Spain [2], while another study in Canada reported 10% SLS cases among 110 patients [3]. Here we present a young lady with SLE, whose recurrent dyspnoea was due to SLS.…”

“…The finding of anti-Ro antibodies in various reports wase conflicting. Two case series reported that it is found in the majority of patients with SLS (10 of 13 [5] and 6 of 7 patients [6]), while another case series of 31 SLE patients, reported the presence of anti-Ro antibodies in 35% patients only [2]. Seropositivity for anti-RNP had also been reported to be significantly associated with SLS [3].…”

“…The main presentation of SLS is dyspnoea, which was reported to be present in more than 98% [2,5] of patients with SLS. Majority presented with exertional dyspnoea and later progressed to dyspnoea at rest [5], which was the main feature of SLS in our patient and this was one of the basis of her diagnosis.…”

Dyspnoea in lupus

“…Because it is rare, diagnosis is often missed or delayed as physicians search for other causes of dyspnoea. As already discussed, management is largely based on case series and includes glucocorticoids and immunosuppressive agents such as azathioprine, cyclophosphamide and, more recently, rituximab 6. Eighteen per cent of patients return to baseline function with no functional sequelae while 80% showed mild/moderate improvement in pulmonary function test (PFTs) but persistence of a restrictive defect 6…”

“…A literature review found that 95% of patients were given glucocorticoids 6. Just over 50% of patients were given additional immunosuppressive agents, the most popular were azathioprine and cyclophosphamide while methotrexate and mycophenolate mofetil have also been used with variable outcomes; however, more recently, a number of cases have been treated successfully with rituximab 6…”