Event Title
A case of double-positive anti-GBM and MPO-ANCA vasculitis with no pulmonary involvement
Location
Philadelphia, PA
Start Date
3-5-2023 1:00 PM
End Date
3-5-2023 4:00 PM
Description
Introduction
Anti-glomerular basement membrane (anti-GBM) disease is a small vessel vasculitis caused by autoantibodies directed at the glomerular and alveolar basement membranes. Anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis is pauci-immune with no immune deposits. Both vasculitides can lead to precipitation of rapidly progressive glomerulonephritis and diffuse alveolar hemorrhage. We report a case of a 58 year-old male who presented with acute renal failure with double positive anti-GBM and myeloperoxidase-anti neutrophil cytoplasmic antibodies (MPO-ANCA) but no pulmonary involvement.
Case Presentation
Patient is a 58-year-old male with a past medical history of nicotine dependence who presented to the hospital with abnormal blood work. Three weeks before this presentation, he developed malaise, weakness, and vomiting and was admitted for acute kidney injury with a creatinine of 6.3 mg/dL and BUN of 104 mg/dL. Patient was discharged to follow up with outpatient nephrology. Two weeks later, the patient developed a diffuse macular rash involving his trunk and all four extremities. Initial work-up by his nephrologist revealed an elevated anti-MPO titer (10.6) and positive p-ANCA (1:80). The patient was started on a tapered steroid dose.
During this hospital admission, the patient’s blood work showed significantly elevated creatinine of 24.2 mg/dL and BUN of 162 mg/dL. He also had metabolic acidosis with a bicarbonate level of 13 mmol/L and hyperkalemia of 5.7 mmol/L. The patient was started on pulse dose steroids and required initiation of dialysis. Despite no confirmed diagnosis, plasmapheresis was started and continued every other day for 7 treatments. Renal biopsy was obtained and demonstrated crescentic glomerulonephritis with linear staining of the glomerular basement membrane by IgG, consistent with anti-GBM disease. Biopsy results confirmed concurrent ANCA-mediated glomerulonephritis. Chest x-ray was obtained and showed clear lungs without pneumothorax, effusion, or any lung involvement.
Patient clinically improved after completion of plasmapheresis. Anti-GBM antibody was less than 1 AI on the last day of treatment. Patient remained dependent on dialysis and started on cyclophosphamide. If anti-GBM titer is still positive after 6 months of cyclophosphamide, rituximab or mycophenolate will be considered. If renal function does not improve, he will be placed on the transplant list.
Discussion
Approximately half of anti-GBM disease patients are double positive for anti-GBM and ANCA and up to 10% of ANCA-vasculitis patients are also positive for anti-GBM. This subgroup of patients is found mainly in males ages 60-70. Renal manifestation of anti-GBM disease typically presents as acute kidney injury with urinalysis showing proteinuria, dysmorphic red cells, white blood cells, and granular casts. Pulmonary involvement includes complaints of shortness of breath, cough, hemoptysis, and pulmonary infiltrates on chest radiographs. ANCA-vasculitis is systemic and can result in pulmonary hemorrhage and renal involvement ranging from asymptomatic hematuria with normal function to end-stage renal disease. However, as seen in this case, absence of pulmonary involvement cannot rule out anti-GBM disease in a patient with concurrent ANCA-vasculitis.
Embargo Period
6-28-2023
Included in
A case of double-positive anti-GBM and MPO-ANCA vasculitis with no pulmonary involvement
Philadelphia, PA
Introduction
Anti-glomerular basement membrane (anti-GBM) disease is a small vessel vasculitis caused by autoantibodies directed at the glomerular and alveolar basement membranes. Anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis is pauci-immune with no immune deposits. Both vasculitides can lead to precipitation of rapidly progressive glomerulonephritis and diffuse alveolar hemorrhage. We report a case of a 58 year-old male who presented with acute renal failure with double positive anti-GBM and myeloperoxidase-anti neutrophil cytoplasmic antibodies (MPO-ANCA) but no pulmonary involvement.
Case Presentation
Patient is a 58-year-old male with a past medical history of nicotine dependence who presented to the hospital with abnormal blood work. Three weeks before this presentation, he developed malaise, weakness, and vomiting and was admitted for acute kidney injury with a creatinine of 6.3 mg/dL and BUN of 104 mg/dL. Patient was discharged to follow up with outpatient nephrology. Two weeks later, the patient developed a diffuse macular rash involving his trunk and all four extremities. Initial work-up by his nephrologist revealed an elevated anti-MPO titer (10.6) and positive p-ANCA (1:80). The patient was started on a tapered steroid dose.
During this hospital admission, the patient’s blood work showed significantly elevated creatinine of 24.2 mg/dL and BUN of 162 mg/dL. He also had metabolic acidosis with a bicarbonate level of 13 mmol/L and hyperkalemia of 5.7 mmol/L. The patient was started on pulse dose steroids and required initiation of dialysis. Despite no confirmed diagnosis, plasmapheresis was started and continued every other day for 7 treatments. Renal biopsy was obtained and demonstrated crescentic glomerulonephritis with linear staining of the glomerular basement membrane by IgG, consistent with anti-GBM disease. Biopsy results confirmed concurrent ANCA-mediated glomerulonephritis. Chest x-ray was obtained and showed clear lungs without pneumothorax, effusion, or any lung involvement.
Patient clinically improved after completion of plasmapheresis. Anti-GBM antibody was less than 1 AI on the last day of treatment. Patient remained dependent on dialysis and started on cyclophosphamide. If anti-GBM titer is still positive after 6 months of cyclophosphamide, rituximab or mycophenolate will be considered. If renal function does not improve, he will be placed on the transplant list.
Discussion
Approximately half of anti-GBM disease patients are double positive for anti-GBM and ANCA and up to 10% of ANCA-vasculitis patients are also positive for anti-GBM. This subgroup of patients is found mainly in males ages 60-70. Renal manifestation of anti-GBM disease typically presents as acute kidney injury with urinalysis showing proteinuria, dysmorphic red cells, white blood cells, and granular casts. Pulmonary involvement includes complaints of shortness of breath, cough, hemoptysis, and pulmonary infiltrates on chest radiographs. ANCA-vasculitis is systemic and can result in pulmonary hemorrhage and renal involvement ranging from asymptomatic hematuria with normal function to end-stage renal disease. However, as seen in this case, absence of pulmonary involvement cannot rule out anti-GBM disease in a patient with concurrent ANCA-vasculitis.