The Patient With ANCA-Associated Vasculitis
A 27-year-old women presents to the office with a 5-week history of purulent nasal secretions, diffuse joint pains and a nonproductive cough. She takes no medications and her family history is negative.
Her physical examination reveals a temperature of 101.5°F, blood pressure of 140/86 bilaterally; pulse is 101 bpm; and her respiratory rate is 19 per minute. The nasal turbinates are inflamed with purulent, blood-streaked secretions. Diffuse rhonchi were noted bilaterally. No joint swelling, tenderness or rashes were noted. Neurological exam was normal.
Her lab studies were: hemoglobin = 11.4 g/dL; white blood cell count = 12,500/mL; platelet count = 427,000/mL; antinuclear antibodies = positive; p-antineutrophil cytoplasmic antibodies = positive; antimyeloperoxidase antibodies = positive; and renal function and urinalysis are normal. Chest radiographs show nodular infiltrates, while a CT scan of the paranasal sinuses demonstrates diffuse opacifications. Sputum culture, gram stain and QuantiFERON gold testing are negative.
Key Supporting Information
The ANCA antigen is of vital importance in determining the disease process and prognosis for systemic vasculitis. ANCA-associated vasculitides (AAV) comprise three types: granulomatosis with polyangiitis (GPA; Wegener’s), eosinophilic granulomatosis with polyangiitis (EPGA; Churg-Strauss syndrome), and microscopic polyangiitis (MPA). Their common pathologic feature is a necrotizing small-vessel vasculitis commonly affecting multiple organs, including lungs and kidneys (pulmonary–renal syndromes). The clinical phenotype is highly variable and reflects the pattern of vessels affected by inflammation. The association of p-ANCA positivity, along with the presence of antimyeloperoxidase (anti-MPO) antibodies, is associated with microscopic polyangiitis. This is characterized by rapidly progressive glomerulonephritis or pulmonary hemorrhaging, arthralgias, fevers, purpura and mononeuritis multiplex.
The overall annual incidence of AAV is approximately 10 to 20 per million people, with a peak age of onset in those aged 65 years to 74 years. Untreated AAV carries a dismal prognosis. A natural history study found average patient survival was approximately 5 months post-diagnosis; more than 90% died within 2 years. In 2011, the FDA approved rituximab (Rituxan, Genetech) in combination with glucocorticoids for the treatment of GPA and MPA, making it the first FDA-approved agent for the treatment of AAV. This addition to the AAV armamentarium has expanded treatment options while adding more complexity.
The definitive and timely diagnosis of AAV is challenging. The disease presents with diverse symptoms with a wide spectrum of organ involvement and severity. In the absence of overt hematuria, which is uncommon, patients frequently do not notice symptoms or seek treatment until severe chronic damage has ensued. Disease manifestations may involve the lungs, upper respiratory tract, peripheral nerves, skin, and joints. Constitutional symptoms such as fever, weight loss, joint and muscle aches, and flu-like illness broaden the differential diagnosis. There are still no validated diagnostic criteria for AAV.
Delays in the diagnosis of AAV may occur based on absent or nonspecific symptoms. A 2013 study assessed symptoms and number of physicians seen prior to renal biopsy in 127 patients with an AAV diagnosis. Delayed diagnosis was common, especially in patients who presented with non-renal manifestations of disease. Among patients who sought direct care, 71% experienced a delay in referral to a nephrologist. More than half of patients presenting with prodromal flu or upper respiratory involvement waited more than a month to see a physician or had delayed specialist referral. Patients with a severe loss of renal function were more likely to have a direct referral to a nephrologist.
Once treatment is underway, it is important for physicians to recognize that not all manifestations of vasculitis, particularly the damage inflicted by low disease activity and the toxic effects of therapy, will respond to immunosuppression. Learning to identify which manifestations of vasculitis are unlikely to respond to immunosuppression is essential to avoid the toxicities brought about by overtreatment.
In a recent online CME activity describing a patient with a symptom complex and findings of the physical examination, biopsy and laboratory workup consistent with seronegative granulomatosis with polyangiitis and Wegener’s granulomatosis (GPA/WG), 34% of physicians failed to make the correct diagnosis. In addtion, when determining next steps for a patient with symptoms suggestive of GPA/WG and pulmonary-renal syndrome, fewer than 50% of physicians recognized that hospital admission was necessary to monitor the rate of disease progression and to initiate aggressive therapy
Upon successful completion of this educational activity, participants should be better able to assess ankylosing spondylitis.
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Author(s)/Faculty: Ronald A. Codario, MD, FACP, FNLA, RPVI, CCMEP
Source: Healio Rheumatology Education Lab
Release Date: 9/15/2015
Expiration Date: 9/15/2016
Credit Type: CME
Number of Credits: 1
Provider: Vindico Medical Education
Provider Statement: This continuing medical education activity is provided by Vindico Medical Information.
Support Statement: No commercial support for this activity.
Target Audience: This activity is designed for this activity is rheumatologists and other health care professionals involved in the treatment of patients with rheumatological disorders.