Severe Mononeuritis Multiplex in Eosinophilic Granulomatous Polyangiitis: A Case Report

This report describes a 48-year-old man who presented with a month history of weakness and paraesthesia associated with severe pain of all four limbs. Initially diagnosed and treated as Guillain Barre syndrome due to the severity of his extremity weakness, it was later discovered to be eosinophilic granulomatous polyangiitis (EGPA). Mononeuritis multiplex should not be underestimated or overlooked in the setting of diagnosing EGPA and requires prompt treatment with biologics to limit the permanent consequences on patient's quality of life with regard to developing limb weakness and pain.  Although peripheral neuropathy, namely, mononeuritis multiplex, is not the most common feature of EGPA, it is important to consider it in order not to delay treatment with biologic agents that as seen in our patient can both halt the progress of the disease as well as give the patient a better quality of life.

ANCA-negative ANCA-associated vasculitis: pitfalls of the 'vasculitis screen'

Despite its recognition as an 'ANCA-associated vasculitis' (AAV), eosinophilic granulomatosis with polyangiitis (EGPA) is ANCA negative in up to 60% of cases. Herein, we report the case of a young man with a clinical syndrome highly suggestive of EGPA but with repeated negative ANCA serology, ultimately presenting with cardiac arrest before recognition of the primary systemic vasculitis, whereupon he received successful induction therapy with high dose glucocorticoids and cyclophosphamide. The case illustrates the importance of awareness of ANCA negative AAV among general physicians in order to minimise morbidity and mortality.

A case of renal vein thrombosis associated with autoimmune hemolytic anemia and eosinophilic granulomatous polyangiitis

Only a few cases of renal vein thrombosis (RVT) occurring in patients with vasculitis have been reported. RVT associated with vasculitis and hemolytic anemia has not been reported yet. We describe here a patient with RVT complicated by pulmonary embolism, autoimmune hemolytic anemia, and eosinophilic granulomatous polyangiitis. A 69-year-old Japanese man who had been treated with corticosteroids was referred to our department for severe proteinuria (4.32 g/gCr). Abdominal ultrasonography showed bilateral RVT, and contrast-enhanced computed tomography showed bilateral pulmonary embolism. Therefore, the patient was diagnosed with RVT complicated by pulmonary embolism. Anticoagulation therapy with heparin followed by apixaban was started. Thereafter, the D-dimer concentration decreased from 8.3 to 1.2 μg/mL, and urinary protein excretion improved to 0.62 g/gCr. Renal function was unchanged with an estimated glomerular filtration rate of 68.8 mL/minute/1.73 m2. The thrombi in both renal veins and pulmonary arteries gradually regressed. Clinicians should be aware of this complication when worsening proteinuria is observed during steroid therapy in patients with autoimmune hemolytic anemia and eosinophilic granulomatous polyangiitis.

Incidence of PR3- and MPO-ANCA autoantibody specificity changes in ANCA-associated vasculitis

BACKGROUND

Monitoring of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in remission usually includes indirect immunofluorescence (IIF), proteinase 3 (PR3)-ANCA and myeloperoxidase (MPO)-ANCA. Typically, PR3 and MPO-ANCA are both performed because patients sometimes switch specificity during follow up. Published data are limited to case reports and incidence of change is not reported. The aim of this study was to quantify the incidence of antibody switching.

METHODS

Hull and East Yorkshire Hospitals National Health Service Trust serves a population of 720,000 for ANCA testing. We reviewed all ANCA results from January 2000 to August 2012 to quantify incidence of antibody switching. A total of 22,002 IIF screens (14,518 patients) were performed. A total of 9838 (45%) also had PR3- and MPO-ANCA (6439, 44% of patients). Patients that changed specificity from PR3- to MPO-ANCA and vice versa were identified and case notes reviewed.

RESULTS

A total of 218 patients with confirmed AAV positive for PR3/MPO-ANCA were followed for a mean of 2.6 years (range <0.1 to 12.4 years; with 113 (52%) patients followed for >1 year). Five patients (2%) changed specificity during follow up (3 GPA, 1 MPA & 1 EGPA). In two patients this was associated with relapse. Incidence of specificity change was 1 per 82 years (including two reversions to presenting specificity) and one per 286 years for changes associated with relapse. Monitoring using only the initial antibody specificity would have resulted in missed relapse in one patient.

CONCLUSION

Antibody specificity changes in AAV are rare. Monitoring only the initial antibody specificity would have missed clinical events but rising C-reactive protein presaged relapse in these cases.