Systemic Lupus Erythematosus and ANCA-Associated Vasculitis Overlap Syndrome: A Case Report

Abstract

Concomitant lupus nephritis and antineutrophil cytoplasmic antibody-positive crescentic glomerulonephritis is rare, and there is little guidance on the management and outcomes of these patients. A Hispanic woman in her early 40s with no contributory medical history presented with 3 weeks of cough, shortness of breath, fever, and malaise. Laboratory test results were notable for serum creatinine level of 17.4 mg/dL (previously normal), urinalysis with a high hemoglobin level, >182 red blood cell count, and urinary protein-creatinine ratio of 5.72 g/g. Serologies showed elevated dsDNA, ribonucleoprotein antibody, Smith antibody, myeloperoxidase antibody, positive antinuclear antibody, and low complement levels. She was urgently started on hemodialysis and solumedrol 1 g for 3 days. On day 2, she had a kidney biopsy, which showed necrotizing crescentic glomerulonephritis and immunofluorescence with "full house" pattern, immune complex deposits, and strong antinuclear antibody staining of nuclei. She developed diffuse alveolar hemorrhage and was initiated on plasmapheresis and cyclophosphamide. She improved and was discharged without needing further dialysis. Clinicians should consider systemic lupus erythematosus and antineutrophil cytoplasmic antibody disease overlap syndrome when a young, female patient presents with new kidney failure and alveolar hemorrhage. Early biopsy and aggressive treatment are essential in preserving kidney function, and plasmapheresis should be considered in severe cases. This is a severe case with a positive outcome.

Keywords: antineutrophil cytoplasmic antibody-associated vasculitis; glomerulonephritis; overlap syndrome; systemic lupus erythematosus.

Figure 1

Periodic acid–Schiff stained sections of the kidney biopsy illustrate 2 representative glomeruli with relatively mild mesangial and endocapillary proliferation. However, both have cellular crescents. A crescent compresses the right side of bottom glomerulus. In the upper glomerulus, the arrow points to fibrin in Bowman’s space, and a developing crescent surrounds the fibrin. Immunofluorescence microscopy demonstrates IgG-dominant immune deposits, in a mesangial and capillary wall distribution. IgG also highlights glomerular and tubulointerstitial nuclei, which is typically associated with high serum antinuclear antibody levels. C3, IgA, IgM, and C1q staining is weaker, segmental, and predominantly mesangial granular. Abbreviations: Ig, immunoglobulin; PAS, Periodic acid– Schiff.

Figure 2

Trend of serum creatinine levels by hospital date and date of interventions, including dialysis, immunosuppression, steroids, and plasmapheresis. Abbreviations: Cr, creatinine.