A Malady with Many Manifestations: A Case of Eosinophilic Granulomatosis with Polyangiitis

Summary: Background: Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare ANCA-associated small vessel vasculitis. The disease often begins with a prodromal phase involving symptoms such as asthma, allergic rhinitis, and sinusitis. Later, patients may develop cutaneous, sinus, pulmonary, renal, cardiac, GI, or neurologic manifestations of vasculitis. This case of EGPA features inflammatory arthritis and tenosynovitis among the primary presenting symptoms. Case: A 49-year-old female with a history of sinusitis and eosinophilia presented to our hospital with complaints of joint pain, swelling, and rash involving her arms and legs for 2 weeks. She initially had pain in her left ankle, then later in both wrists. She also described a migratory burning, stabbing pain in her extremities. She was unable to ambulate due to pain. She had already been treated with antibiotics for cellulitis with no improvement, and with indomethacin for presumed gout with minimal improvement. The patient reported a hospital admission one year earlier for pseudomonas pneumonia. She was noted to have elevated eosinophils and IgE levels at that time. Ten months later she was admitted for hypoxic respiratory failure. A bronchoscopy reportedly showed nonspecific inflammation, but no organisms. She was treated with steroids for several weeks and her symptoms improved. A physical exam demonstrated prominent edema and erythema of the right dorsal hand (Figure 1A). She had swelling of both wrists and the left ankle. There was non-pitting edema in the lower extremities. She was exquisitely tender to palpation of right hand, bilateral wrists, bilateral lower legs, ankles, and feet. Several small purpuric papules were present on the arms and legs, with the majority located on the elbows. She additionally had ulcers on the roof of her mouth. Her lungs were clear to auscultation. Cardiac and abdominal exams were normal. Laboratory evaluation showed eosinophilia of 2.04 x 10*3/uL. Her ESR was 22 mm/hr and CRP was 2.86 mg/dL. Rheumatoid factor was 55 IU/mL. CCP was negative. Uric acid was 1.9 mg/dL. IgE was 659 kU/L (Reference <114 kU/L). She had a positive MPO ANCA of 28.2. X-rays of the hands and feet showed some mild degenerative changes. Though she had no respiratory symptoms, a CT scan of the chest showed a collapsed left lung concerning for pneumonia. She also had pansinusitis on a CT of the sinuses. An MRI of the right hand was notable for extensor compartment 4 tenosynovitis, soft tissue edema, and synovitis of the wrist (Figure 1B). An echocardiogram was normal. Infectious workup, including for causes of eosinophilia, was negative. Evaluation by neurology indicated the pain and hyperesthesia in her extremities was likely a peripheral sensory neuropathy. A skin biopsy of one of the lesions on the patient’s elbow showed leukocytoclastic vasculitis with prominent eosinophils (Figure 2). Discussion: The patient was diagnosed with EGPA with evidence of skin, joint/tendon, lung, sinus, and nerve involvement. She was started on prednisone 60mg daily with rapid improvement in her joint pain and swelling, though her neuropathic pain persisted. Due to the severity of her neuropathy, she was offered cyclophosphamide, but declined due to concern for side effects and requested to be discharged. A close follow-up was arranged to start steroid-sparing therapy but the patient chose to establish with a different provider. While arthralgias and myalgias are commonly documented among the constitutional symptoms seen in EGPA, frank synovitis and tenosynovitis are unusual. This patient did have a positive rheumatoid factor, so an overlap syndrome between rheumatoid arthritis (RA) and EGPA is a possibility. However, the oligoarticular nature and rapid onset of the symptoms is less consistent with RA. The joint pain combined with the patient’s peripheral neuropathy were very debilitating such that she was non-ambulatory. This may have influenced the distribution of her palpable purpura, which was unusually concentrated on her elbows. These lesions may have been provoked by friction or pressure from the patient using her elbows to reposition and transfer in bed because of the pain in her legs and hands. Conclusions: This case demonstrates features inflammatory arthritis and tenosynovitis as prominent symptoms in a patient with EGPA which could represent a rare manifestation of the vasculitis or possibly an overlap syndrome with RA.