SESSION TYPE: Miscellaneous Case Report Posters II
PRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM
INTRODUCTION: Previously known as Wegener’s granulomatosis, granulomatosis with polyangiitis (GPA) is an antineutrophil cytoplasmic antibody (ANCA) associated vasculitis characterized by necrotizing granulomatous inflammation of small vessels . This disease process often affects the lungs, nose, sinuses, kidneys, and other sites throughout the body. Diagnosis is typically made through a combination of clinical, radiographic, biopsy, and laboratory findings. The presence of ANCA is one of the most important elements of the diagnostic process, and approximately 90% of patients with GPA will be ANCA positive. Of these, the majority will have anti-PR3 antibodies. The presence of ANCA can be assessed via two methods. The more sensitive and less specific method is immunofluorescence. While sensitivity can vary greatly between labs, a general estimate is 70%. ELISA, on the other hand, tends to be less sensitive and more specific, with an estimated sensitivity of 50%. Therefore, most diagnostic algorithms suggest initial testing with immunofluorescence, and confirmatory testing with ELISA. We report a patient with GPA diagnosed with negative immunofluorescence and positive ELISA for PR3.
CASE PRESENTATION: After presenting with several weeks of hemoptysis and dyspnea, this 43-year-old woman had a chest CT, which revealed diffuse mass-like consolidation, associated with bronchovascular bundles. Routine laboratory evaluation revealed a creatinine of 1.4 and a urinalysis with RBC casts. Bronchoscopy was performed which showed normal airways, a bloody broncho-alveolar lavage, and transbronchial biopsies revealing acute and chronic inflammation with hemorrhage. A VATS lung biopsy was performed but was non-diagnostic. All stains and cultures for infection were negative. Immunofluorescence was negative for C-ANCA or P-ANCA, however, an ELISA was also performed and was positive for PR3. Based on the clinical, radiographic, and ELISA findings a diagnosis of GPA was made. The patient was started on Cytoxan and prednisone and her symptoms quickly improved. The previously demonstrated radiographic findings resolved on repeat imaging.
DISCUSSION: This case highlights the fact that there is no test for GPA that has 100% sensitivity, including surgical biopsy.
CONCLUSIONS: When clinical suspicion is high, immunofluorescence for ANCA and ELISA testing for proteinase III antibodies should be ordered to improve the diagnostic yield for this life threatening but treatable disease .
1) Falk RJ, Gross WL, Guillevin L, et al. Granulomatosis with polyangiitis (Wegener's): an alternative name for Wegener's granulomatosis. Arthritis Rheum 2011; 63: 863.
2) Jayne D. The diagnosis of vasculitis. Best Practice and Research Clinical Immunology 2009; 23: 445.
DISCLOSURE: The following authors have nothing to disclose: Travis Greer, Nicholas Pastis
No Product/Research Disclosure InformationMedical University of South Carolina, Charleston, SC