Abstract: PO1512
C2 Deficiency Associated with Severe Recurrent ANA-Negative Lupus and Microangiopathy
Session Information
- Glomerular Diseases: The Excitement of Clinical Cases
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Llanos, Maria, NewYork-Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York, United States
- Marino, Daniel, NewYork-Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York, United States
- Menon, Sanjay K., NewYork-Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York, United States
- Neelakantappa, Kotresha, NewYork-Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York, United States
- Malekan, Michael, NewYork-Presbyterian Brooklyn Methodist Hospital, Brooklyn, New York, United States
Introduction
Deficiencies in the classical complement pathway have been associated with the development of systemic lupus erythematosus (SLE) and lupus-like disease in 10-20% of affected patients. In fact, SLE patients deficient in classical complement present at an earlier age, with severe manifestations and a worse prognosis. Several mechanisms have been described to explain these immune phenomena including impaired clearance of immune complexes, impaired handling of apoptotic cells, or changes in regulation of cytokines. Here, we present a case of a young female with ANA-negative lupus presenting with dyspnea and acute renal failure responsive to immunosuppressive therapy found to have C2 Complement deficiency.
Case Description
44 year old female with sickle cell trait, ANA-negative SLE, ESRD due to biopsy-proven class IV lupus nephritis briefly requiring HD, pulmonary HTN, presented with signs of fluid overload, acute on chronic renal failure in the setting of malignant hypertension. Labs revealed thrombocytopenia of 52 with a creatinine of 2.66 (prior 1.61), hypocomplementemia and undetectable CH50 levels concerning for acute flare of SLE and an underlying functional complement deficiency. Low haptoglobin and peripheral smear with schistocytes raised concerns for microangiopathy. Hospital course was complicated by encephalopathy and possible CNS involvement of lupus. Renal biopsy confirmed chronic sclerosing immune complex glomerulonephritis with minimal activity. The patient responded well to high dose corticosteroids, plasma exchange and mycophenolate mofetil. Final serology confirmed persistent C2 complement deficiency.
Discussion
There is a well-studied link between immune-complex mediated disease and complement deficiency. Of these, C2 deficiency is the most common. In our case, a C2 deficiency was found in the setting of ANA-negative SLE with severe clinical manifestations. Our case raises the question of whether testing to exclude underlying complement deficiency is particularly indicated in patients with ANA-negative SLE. It also remains to be seen whether clinical manifestations of microangiopathy are prevalent in these patients, and whether therapeutics targeting complement may be effective in their treatment.