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An Immunohistopathologic Study to Profile the Folate Receptor Beta Macrophage and Vascular Immune Microenvironment in Giant Cell Arteritis
Published on: February 8, 2019
Microscopic polyangiitis: a large single-center series
Leslie Wilke1, Marilynn Prince-Fiocco, Guy Peter Fiocco
1From the Division of Pulmonary/Critical Care, Department of Internal Medicine, Scott & White Healthcare/Texas A&M Health Science Center College of Medicine, Temple, Texas.
Objective:
Microscopic polyangiitis (MPA) is a rare systemic vasculitis, antineutrophil cytoplasmic antibody associated, characterized by necrotizing small vessel involvement with few or no immune complex deposits. Necrotizing glomerulonephritis is common. Pulmonary capillaritis causing alveolar hemorrhage and hemoptysis is well recognized, but most case series are reported in the nephrology literature and emphasize renal considerations. We present a single-center 10-year retrospective review of 40 patients meeting the 2012 Revised Chapel Hill Nomenclature of MPA, with specific p-antineutrophil cytoplasmic antibody and myeloperoxidase positivity, emphasizing initial and subsequent pulmonary manifestations.
Methods:
We searched the electronic database of our large integrated clinic-hospital system and reviewed charts of all patients with related International Classification of Diseases, Ninth Revision codes for vasculitis in the last 10 years. Several variables were reviewed.
Results:
Onset of illness was usually abrupt and included respiratory symptoms, and the most common presenting complaint was cough. Hemoptysis occurred during the course of illness in 40%. Pulmonary complaints were found in 80% of patients upon presentation, whereas pulmonary infiltrates were noted in 92%. Managing subspecialty and treatment modalities were quite variable.
Conclusions:
Pulmonary involvement is much more frequent than the currently reported 25% to 50% when features in addition to hemorrhage are recorded. No clear guidelines direct the evaluation and management of MPA patients. Consistent communication between pulmonary, nephrology, and rheumatology services could improve our understanding of the disease process.
Insights
Microscopic polyangiitis (MPA) frequently involves the lungs, often presenting with respiratory symptoms like cough and infiltrates. This study highlights the high prevalence of pulmonary issues in MPA patients, urging better interdisciplinary care.
Area of Science:
- Rheumatology
- Pulmonology
- Nephrology
Background:
- Microscopic polyangiitis (MPA) is a rare systemic vasculitis associated with antineutrophil cytoplasmic antibodies.
- Characterized by necrotizing small vessel vasculitis, MPA commonly affects the kidneys and lungs.
- Pulmonary capillaritis leading to alveolar hemorrhage and hemoptysis is recognized, but often underemphasized in literature focused on renal aspects.
Purpose of the Study:
- To review pulmonary manifestations in microscopic polyangiitis (MPA) over a decade.
- To emphasize initial and subsequent pulmonary involvement in MPA patients with specific antibody positivity.
- To highlight the frequency of pulmonary symptoms beyond alveolar hemorrhage.
Main Methods:
- A single-center, 10-year retrospective review of 40 patients meeting the 2012 Revised Chapel Hill Nomenclature for MPA.
- Patient charts were reviewed using International Classification of Diseases, Ninth Revision codes for vasculitis.
- Data on initial presentation, pulmonary manifestations, and treatment were analyzed.
Main Results:
- The onset of MPA was typically abrupt, with respiratory symptoms being common, and cough the most frequent initial complaint.
- Pulmonary complaints were present in 80% of patients at presentation, with 92% showing pulmonary infiltrates.
- Hemoptysis occurred in 40% of patients during the illness course.
Conclusions:
- Pulmonary involvement in MPA is significantly more common than previously reported (25-50%), especially when considering symptoms beyond hemorrhage.
- Current evaluation and management guidelines for MPA are lacking.
- Improved communication among pulmonary, nephrology, and rheumatology services is crucial for better disease understanding and patient care.
