Granulomatosis with Polyangiitis: A Case of Nasal Mass, Necrotic Lung, and Normal Kidneys

Abstract

A diagnosis of granulomatosis with polyangiitis (GPA) can be challenging given various clinical manifestations. We report an incident case of GPA presenting with chronic sinusitis and mimicking an early lung abscess without renal involvement. A 51 year-old woman with chronic obstructive sinusitis presented with subacute dyspnea, pleuritic chest pain and fever. Physical examination revealed a right nasal mass without discharge or bleeding. Decreased to absent breath sounds and dullness to percussion were noted at the left lung base. Laboratory findings were significant for leukocytosis but normal renal function. The chest CT demonstrated dense consolidation with hypo-enhancement of the lingula. The sinus CT revealed an enhancing mass in the right nasal cavity and anterior ethmoid sinuses with associated bony destruction. Patient did not improve with empiric antibiotics for lung abscess. Aspiration of the lingular fluid showed purulent material, however, microbes did not grow in culture. A positive C-ANCA screen was confirmed. A right nasal biopsy was performed which revealed granulomatous inflammation with focal necrosis and vasculitis. The final diagnosis was GPA. Given various clinical manifestations, the diagnosis of GPA can be difficult to distinguish from infectious etiologies. This can delay the treatment, which may be life-saving and organ sparing. We emphasize that an initial screening ANCA serology test is recommended in patients with suggestive clinical findings of GPA. Biopsy of an affected organ is paramount for the definitive diagnosis.

Introduction

Granulomatosis with polyangiitis (GPA), previously known as Wegener's granulomatosis, is one of the ANCA-associated vasculitides (AAV). The prevalence and incidence is approximately 30,000 and 2,600 per 300 million people respectively.[1] Clinical manifestations commonly involve multiple organ systems including ear-nose-throat (upper respiratory), pulmonary (lower respiratory system,) and renal systems. Given various manifestations, a diagnosis can be challenging. Antineutrophil cytoplasmic antibody (ANCA) serologies including proteinase-3 (PR-3) and myeloperoxidase (MPO) antibodies and histologic examination of the affected organs are generally required to make the diagnosis of GPA. We report an incident case of GPA presenting with chronic sinusitis and mimicking an early lung abscess without renal involvement.

Case Report

The patient is a 51 year-old Chinese-American woman with history of chronic obstructive sinusitis with right nasal mass who presented with progressive pleuritic chest pain, exertional dyspnea, non-productive cough and fever for two weeks. Upon admission, vital signs include body temperature 38.0 C, blood pressure 130/80 mmHg, pulse rate 105 per minute, respiratory rate 18 per minute and oxygen saturation was 97% on room air. Physical examination revealed a right nasal mass without discharge or bleeding. Decreased to absent breath sounds and dullness to percussion were noted at the left lung base. Bilateral fine crackles were also present in the right lung and left upper lung zone. The exam was otherwise unremarkable. Initial laboratory findings were significant for leukocytosis, WBC 13,000/mm³ with 75% neutrophils, no bands, BUN 12 mg/dL and creatinine 0.5 mg/dl. Urinalysis was unremarkable and without active sediment or proteinuria. The computer tomography (CT) of thorax demonstrated dense consolidation with hypo-enhancement of the lingula which suggested an early lung abscess. A small left pleural effusion was noted (Figure 1). The right lung was without infiltrative lesion. CT of the sinuses revealed a 2.5 × 1.5 cm heterogeneously enhancing mass-like lesion in the upper right nasal cavity and anterior ethmoid sinuses with associated destruction of the anterior body septum and nasal bone. Patient was empirically treated for lung abscess with vancomycin, piperacillin-tazobactam, and azithromycin (Figure 2). The CT-guided needle aspiration of the potential lingular abscess drained purulent material. However, the culture showed no growth. Left pleural fluid was also sterile. Given no response to the empiric treatment for potential lung abscess, non-infectious causes including GPA were suspected. Erythrocyte sedimentation rate and anti-neutrophilic antigen were later obtained which showed 77 mm/hr and <40 respectively. A positive C-ANCA screen was confirmed by positive PR-3 antibody but negative MPO antibody. A right nasal biopsy was performed which revealed granulomatous inflammation with focal necrosis and vasculitis. The patient was diagnosed with GPA (Figure 3).

Figure 1.

CT of thoracic abdominal aorta showed dense consolidation with hypo-enhancement present in the lingula.

Figure 2.

CT of facial and soft tissue showed heterogeneously enhancing mass like lesion in the upper right nasal cavity and anterior ethmoid sinuses with associated destruction of the anterior body septum and nasal bone.

Figure 3.

pathology of right nasal showed diffuse chronic inflammation and coagulative necrosis with multinucleated giant cells forming granulomas which are surrounded by plasma cells, lymphocytes and neutrophils. A number of large vessels showed infiltration by lymphocytes.

Discussion

In regard to various clinical manifestation of GPA due to multiple organ involvement, the upper and lower respiratory and genitourinary systems are commonly affected. Although renal involvement is common in the disease course, only 18 percent of patients have glomerulonephritis at presentation. Glomerulonephritis does subsequently develop in 77 to 85 percent of patients, usually within the first two years of disease onset.^{[2, 3, 4, 5]} Accordingly, normal renal function at presentation cannot rule out GPA as in our patient with chronic sinusitis and pulmonary symptoms without renal involvement. Given various clinical presentations, the diagnosis of GPA can be challenging and difficult to distinguish from infectious etiologies. Most of the time, work up for GPA is started after failure of improvement with empirical antibiotic therapy as in our patient who presented with the early abscess-like lesion, but did not respond to the empiric antibiotics and drainage of the potential lung abscess. This can delay the diagnosis and further delay treatment.

In patients with clinical manifestations suspicious for GPA, ANCA serologies should be tested. Cytoplasmic localization of ANCA (c-ANCA) is 90–95% sensitive in acute generalized GPA and 60% sensitive in early or localized disease.[6] A positive ANCA serologies should be confirmed with PR-3 and MPO antibodies which are more specific. A tissue biopsy of an affected organ is required to cinch the diagnosis of GPA[7] which may show specific abnormalities, such as vasculitis, granulomas, giant cells and necrosis. The sensitivity and specificity of tissue biopsy varies depending on a site of active disease. Even though nasal biopsy has higher rate of false negativity when compares to biopsy at other affected sites, it is less invasive and should be considered early in the evaluation. Prompt diagnosis is important to initiate therapy which may be life -saving and organ sparing.

Therapy of GPA is comprised of two components which are induction of complete remission and maintenance therapy. Induction phase treatment includes combination of glucocorticoids plus cyclophosphamide for three to six months to achieve remission. Plasma exchange therapy is suggested in the presence of diffuse pulmonary hemorrhage, rapidly worsening kidney function or overlap syndrome of AAV and anti-glomerular basement membrane antibody glomerulonephritis as in Goodpasture syndrome. Remission is defined as a clearing of active lesions or resolution of organ dysfunction. For the maintenance therapy, azathioprine or methotrexate is recommended for greater than 18 months.

Promt initiation of treatment for AAV can achieve remission at 6 months in >90% of patients, however, relapse rates approach 50%. Severe vital organ-threatening damage and treatment related adverse events may develop in approximately 25% of patients. Without treatment, the average survival rate is 5 months with one and two year mortality rates of 82% and 90% respectively.

Conclusion

We emphasize that the initial screening ANCA serology test is recommended in patients with suggestive clinical findings of GPA. Biopsy of an affected organ is paramount for the definitive diagnosis. Early initiation of treatment is crucial once the diagnosis is established.

Conflict of Interest

None of the authors identify a conflict of interest.