These Aren't the Paraproteins You Have Been Looking for: A Case of Light Chain Deposition Disease

Abstract

SESSION TITLE: Pulmonary Manifestations of Systemic Disease SESSION TYPE: Affiliate Case Report Slide PRESENTED ON: Tuesday, October 31, 2017 at 08:45 AM - 10:00 AM INTRODUCTION: Light chain deposition disease (LCDD) is a rare paraproteinemia with primarily renal involvement characterized most commonly by kappa light chain deposits in the kidney. While case reports exist, lung involvement continues to be a rare finding. CASE PRESENTATION: 73 year old male with a past medical history of osteoporosis presented with a two month history of back pain and generalized weakness. Initial presentation was notable for pancytopenia as well as acute kidney injury. Serum protein electrophoresis showed an M-spike in the beta region as well as elevated IgA monoclonal protein with light chain specificity. A bone marrow biopsy was performed and showed extensive serous atrophy and markedly hypocellular marrow. Extensive work-up for multiple myeloma remained non-diagnostic. The patient developed respiratory failure requiring intubation. CTA of chest demonstrated diffuse ground glass opacification throughout all lung fields. There was concern for infection, but all cultures including bronchoalveolar lavage were negative. The patient had worsening respiratory and renal function despite aggressive care. Ultimately, family decided to pursue comfort directed care in accordance with patient’s previously stated wishes regarding prolonged mechanical ventilation and dialysis. Renal specimens obtained at autopsy revealed congo red negative fractured intratubular eosinophilic casts with kappa staining on immunofluorescence consistent with light chain deposition disease. Lung pathology revealed diffuse bronchiolitis obliterans with organizing pneumonia as well as congo red negative amorphous eosinophilic material within alveoli consistent with LCDD. DISCUSSION: Light chain deposition disease remains an important differential in plasma cell dyscrasias, particularly AL amyloidosis. Lung involvement of LCDD is an especially rare finding of an already rare disease. While organizing pneumonia is described with hematologic malignancy, it has not been described with LCDD which typically is characterized by nodules and/or cysts. CONCLUSIONS: This case demonstrates an unusual presentation of a rare manifestation of light chain deposition disease. Recognition of secondary bronchiolitis obliterans as a potential manifestation may help avoid critical delays in treatment. Reference #1: Sayed, RH, et al. “Natural history and outcome of light chain deposition disease.” Blood (2015);126:2805-2810 Reference #2: Sheard, S, et al. “Pulmonary light-chain deposition disease: CT and pathology findings in nine patients.” Clinical Radiology (2015); 70;515-522 DISCLOSURE: The following authors have nothing to disclose: Aaron Lampkin, Peter Miller, Tim Gallagher No Product/Research Disclosure Information