Student University of Utah School of Medicine Provo, Utah
Objective: Granulomatosis with polyangiitis (GPA) is a potentially fatal condition which often manifests in the head and neck. Currently, diagnosis relies on antineutrophil cytoplasmic autoantibody (c-ANCA) and proteinase 3 (PR3) serology and mucosal or renal biopsy. However, a significant proportion of patients with a form of GPA limited to the head and neck are seronegative and often biopsy negative. This study evaluates the role for a clinical diagnosis of GPA in the absence of positive laboratory findings.
Method: This was a retrospective review of 143 patients treated in an outpatient otolaryngology clinic at a tertiary care hospital for known or suspected GPA from 1998-2021. Presenting symptoms, C-ANCA/ PR3 status at initial presentation, biopsy results, long term serology results, and time to initiation of treatment were analyzed.
Results: 26 of 143 (18.2%) patients were seronegative; only 3 of these patients (12%) had positive biopsies. 21 (81%) presented with nasal and sinus disease and 5 (19%) presented with airway involvement. Only 4 (15%) patients had renal involvement. Delay in treatment of patients with a negative laboratory workup ranged from 0 months to 11 years. All patients who were seronegative and/or biopsy negative at presentation responded clinically to immunosuppressive therapy.
Conclusion: GPA often presents solely in the upper respiratory tract which can make diagnosis of these limited cases difficult, particularly in seronegative patients. These results suggest that, when GPA is suspected despite negative serology, the diagnosis of GPA should be made on clinical grounds and empiric therapy encouraged to prevent delay in treatment.