A Case of Pulmonary Amyloidosis With Progressive Systemic Involvement

Abstract

INTRODUCTION: Amyloidosis is a group of disorders characterized by abnormal deposition of fibrillar proteins into betapleated sheet configuration. Clinical presentation is heterogenous and depends on the organ involvement. Pulmonary manifestation of amyloidosis may be localized to the lungs or may be a part of the systemic disease. Below, we describe a case of pulmonary nodular amyloidosis with eventual development of widespread multi-organ involvement.CASE PRESENTATION: 79-year-old female with a past medical history of Sjögren Syndrome, Discoid Lupus and Ramsay-Hunt syndrome was found to have numerous bilateral pulmonary nodules as incidental findings on chest x-ray and computed tomography (CT) of the chest. She has no history of tobacco use. Initial CT-guided lung biopsy was inconclusive, showing only interstitial fibrosis and chronic inflammation. She subsequently underwent wedge resections and tissue pathology with Congo red stain, which demonstrated apple-green birefringence of the eosinophilic material under polarized microscopy. Serum electrophoresis revealed a spike in the gamma region, consistent with IgG monoclonal gammopathy. Bone marrow biopsy was negative for plasma cell neoplasm and amyloid infiltration. As the patient was asymptomatic with no evidence of systemic involvement, the treatment plan was focused on surveillance with CT/PET scans. A year later, CT chest revealed increased size of bilateral pulmonary nodules. Repeat CT five months later noted enlarging mediastinal lymph node. Patient subsequently underwent transbronchial needle aspiration, which was negative for malignancy. Repeat CT imaging again noted increased size of bilateral pulmonary nodules and patient underwent right lung core needle biopsy to differentiate between AL amyloidosis and AA amyloidosis. Biopsy confirmed pulmonary nodular amyloidosis with mass spectrometry further classifying as AL amyloidosis. Due to rising NT-proBNP suggesting cardiac involvement, patient was started on bortezomib-based chemotherapy for systemic amyloidosis approximately 26 months into diagnosis. Patient has been responding to treatment with reduction in free light chain and NT-proBNP. Additionally, she is undergoing evaluation at Hershey Penn State for autologous stem cell transplant.DISCUSSION: Diagnosis of amyloidosis is challenging as amyloid proteins can infiltrate virtually any organ system and have diverse clinical presentation. Patients who are asymptomatic with localized amyloidosis do not require chemotherapy. However, patients with localized amyloidosis need complete assessments to confirm the absence of systemic amyloidosis and follow with active surveillance to evaluate for progression. Treatment varies based on the type of amyloidosis, therefore testing for amyloid typing is imperative.CONCLUSIONS: Awareness of systemic amyloidosis is essential as these patients benefit from autologous stem cell transplant and chemotherapy.