Abstract: TH-PO585
A Case Report of Pulmonary Alveolar Proteinosis in a Renal Transplant Recipient
Session Information
- Trainee Case Reports - II
October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Reports
- 1802 Transplantation: Clinical
Authors
- Khor, Candice, Gosford Hospital, Sydney, New South Wales, Australia
- Kumar, Subramanian K., Gosford Nephrology, TERRIGAL, New South Wales, Australia
Introduction
Pulmonary alveolar proteinosis (PAP) is a diffuse lung disease characterised by accumulation of surfactant. Clearance of surfactant by alveolar macrophages is regulated by granulocyte macrophage colony stimulating factor (GM-CSF). Autoimmune PAP due to GM-CSF antibodies is the most common cause of PAP in adults. Secondary causes include dust exposure, haematological malignancy and immunosuppressive medications.
Case Description
A 52 year old man developed progressive shortness of breath, hypoxia and productive cough one year post living unrelated renal transplant for polycystic kidney disease. This is in the context of BK virus nephropathy at three months post-transplant requiring a change in immunosuppressants from tacrolimus and mycophenolate to cyclosporine and leflunomide. A high resolution computed tomography (HRCT) of the chest demonstrated bilateral peri-hilar ground glass opacities. Pneumocystis jiroveci pneumonia (PJP) treatment was commenced with no clinical improvement. Bronchoscopy with bronchoalveolar lavage was inconclusive. The patient underwent a transbronchial biopsy which was positive for periodic acid-Schiff (PAS) proteinaceous material confirming the diagnosis of pulmonary alveolar proteinosis.
There was no evidence of haematological malignancy clinically and on bone marrow biopsy. Immunosuppression was changed to tacrolimus and mycophenolate with no improvement in respiratory symptoms. Serum GM-CSF antibodies subsequently returned positive with titres rising from 0.50 to 0.66 suggestive of autoimmune PAP. Rituximab, intravenous immunoglobulin and plasma exchange were considered however patient responded clinically and radiologically after a total lung lavage.
Discussion
Pulmonary alveolar proteinosis is a rare but important differential diagnosis to consider in patients with subacute onset of dyspnoea and hypoxia with the typical radiological changes of ground glass opacity and interlobular and intralobular septal thickening. Importantly PJP can mimic PAP and must be excluded in an immunosuppressed patient. Primary PAP due to GM-CSF antibodies accounts for the vast majority of adult PAP with whole lung lavage as the gold standard of treatment. Secondary PAP due to haematological malignancy, dust exposure and immunosuppressants must be considered and excluded.