Pulmonary light chain deposition disease: a case series and literature review

Background Light chain deposition disease (LCDD) is a systemic disorder typically characterized by non-amyloid monoclonal immunoglobulin light chain deposition in tissues. LCDD is recognized as a multisystem disease, in which the kidneys and liver are often affected. However, it is rarely encountered as a localized pulmonary disease. This study set out to characterize the clinical manifestations and features of pulmonary light-chain deposition disease (PLCDD) by conducting a retrospective analysis of clinical data obtained from patients, with the aim of improving clinical understanding of PLCDD. Methods Data from inpatients diagnosed with PLCDD at Shanghai Pulmonary Hospital (Shanghai, China) between January 2010 and December 2018 were retrospectively collected and analyzed. Results A total of 4 PLCDD patients confirmed with PLCDD by pulmonary tissue biopsy were analyzed. All of the patients were female and were found by physical examination. Chest images of each patient's lungs showed multiple cystic cavities with nodules. A history of Sjogren's syndrome was present with 1 patient, 2 patients were diagnosed with Sjogren's syndrome after surgery (including 1 diagnosed with Sjogren's syndrome in the 8th year of follow up), and 3 patients had leukopenia. The longest follow-up period was 8 years. During the follow-up period, 2 patients developed pulmonary lesions (1 patient had an enlarged original cystic lesion in basal segment of right lower lobe 2 years after surgery, while the other developed new nodules 7 years after surgery). Conclusions PLCDD is characterized by multiple cystic changes with nodules in both lungs and can be easily complicated by lymphoid diseases such as Sjogren's syndrome. The clinical symptoms cannot be characterized, and the diagnosis depends on lung biopsy.