Renal amyloidosis secondary to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is extremely rare. Here, we reported a 77-year-old woman with ANCA-associated vasculitis. Renal biopsy with Masson trichrome staining showed pauci-immune crescentic glomerulonephritis, and electron microscopy showed amyloid deposition in the mesangial area. Immunofluorescence revealed kappa light chain and lambda light chain negative. Bone marrow biopsy revealed no clonal plasma cell. Finally, she was diagnosed as ANCA-associated vasculitis with secondary renal amyloid A amyloidosis.
Female ; Humans ; Aged ; Glomerulonephritis/diagnosis* ; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/pathology* ; Antibodies, Antineutrophil Cytoplasmic ; Kidney/pathology* ; Amyloidosis/complications*

OBJECTIVEAnti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a disorder with poor prognosis. This study aimed to improve the diagnosis and treatment of ANCA associated vasculitis of children, to analyze the clinical features, pathological characteristics and the prognosis of children with ANCA-associated vasculitis.

METHODFifteen children with ANCA associated vasculitis who were hospitalized from 2003 to 2012 in our hospital were included. Their data of pre-diagnosis status, clinical manifestations, renal pathology, treatment and prognosis were reviewed retrospectively.

RESULTOf the 15 children, 11 were girls and 4 boys with a mean age of 10.7 years. Fourteen children were categorized as microscopic polyangitis. The time to diagnosis varied from 0.5 month to 40 months. Hematuria and proteinuria were revealed by urine analysis in all of them, only 6 children complained with gross hematuria or edema of oliguria. Decreased glomerular filtration rate was revealed in 13 children, 8 of whom had a creatinine clearance rate of less than 15 ml/(min·1.73 m(2)). Twelve children underwent renal biopsy, crescent formation was found in 11 children. Most of the crescents were cellular fibrous crescents or fibrous crescents. Six children were diagnosed as crescentic nephritis; the process of rapidly progressive nephritis was only observed in 2 children. Segmental glomerulosclerosis or global glomerulosclerosis were found in 10 children, 3 of them were diagnosed as sclerotic glomerulonephritis. Anemia and pulmonary injury were the most common extra renal manifestations. Other extra renal manifestations included rash, pain joint, gastrointestinal symptoms, abnormal findings of cardiac ultrasonography and headache. Eight children were treated with steroid combined with cyclophosphamide, 4 were treated with steroid and mycophenolate mofetil, 2 were treated with steroid, cyclophosphamide and mycophenolate mofetil, 3 children were treated with plasma exchange. Fourteen children were followed up for 0.5 month to 4 years. The renal function did not recover in children with creatinine clearance rate of less than 30 ml/(min·1.73 m(2)), who showed crescentic glomerulonephritis or sclerotic glomerulonephritis. The children who had creatinine clearance rate of more than 30 ml/(min·1.73 m(2))had better prognosis.

CONCLUSIONMore attention should be paid to ANCA-associated vasculitis among school age girls with anemia or pulmonary diseases. The renal damage was serious in children; however, the clinical manifestations were not obvious. Children with a creatinine clearance rate of less than 30 ml/(min·1.73 m(2)) had poor prognosis. Early accurate diagnosis is very important.

Adolescent ; Anemia ; etiology ; pathology ; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis ; complications ; diagnosis ; pathology ; Antibodies, Antineutrophil Cytoplasmic ; blood ; immunology ; Biopsy ; Child ; Child, Preschool ; Creatinine ; blood ; Female ; Glomerulonephritis ; pathology ; Hematuria ; etiology ; pathology ; Humans ; Kidney ; pathology ; physiopathology ; Kidney Function Tests ; Male ; Nephritis ; diagnosis ; etiology ; pathology ; Prognosis ; Proteinuria ; etiology ; pathology ; Retrospective Studies

BACKGROUNDPrimary anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a chronic autoimmune disease associated with multisystem dysfunction. Renal involvement is common and closely associated with outcome. The purpose of this study was to investigate the clinical determinants of mortality of patients with AAV-related renal injury in the first 2 years after diagnosis in a single West Chinese center.

METHODSDemographic and laboratory parameters of 123 consecutive patients with AAV-related renal injury diagnosed in Renal Division and Institute of Nephrology, Sichuan Provincial People's Hospital between 2004 and 2012 were collected retrospectively. All patients were followed up for 2 years after diagnosis. Survivors were compared with nonsurvivors to identify the clinical baseline variables associated with mortality. Multivariate Cox regression model was used to determine the independent predictors of mortality.

RESULTSOf the 123 patients, 46 (37.4%) died by the end of 2 years after diagnosis, with 41 (33.3%) patients dying within the first 12 months. In comparison with the survivors, Birmingham Vasculitis Activity Score (BVAS), the incidence of pulmonary hemorrhage and digestive system (DS) involvement, serum creatinine, and erythrocyte sedimentation rate were significantly higher in nonsurvivors, whereas lymphocyte counts, hemoglobin, and complement 3 (C3) were significantly lower. Renal replacement therapy was more common in nonsurvivors. High BVAS (hazard ratio [HR] = 1.058, 95% confidence interval [CI]: 1.002-1.117; P = 0.042), pulmonary hemorrhage (HR = 1.970, 95% CI: 1.033-3.757; P = 0.04), DS involvement (HR = 2.911, 95% CI: 1.212-6.911; P = 0.017), and serum creatinine >400 μmol/L (HR = 2.910, 95% CI: 1.271-6.664; P = 0.012) were independent predictors of death in patients with AAV-related renal injury.

CONCLUSIONSPatients with AAV-related renal injury have high early mortality. Those with high BVAS (particularly with pulmonary or DS involvement) and serious renal dysfunction should receive aggressive therapy and careful monitoring to reduce the occurrence of adverse events and improve prognosis.

Adult ; Aged ; Aged, 80 and over ; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis ; drug therapy ; immunology ; pathology ; Autoantibodies ; immunology ; Autoimmune Diseases ; drug therapy ; immunology ; pathology ; Cyclophosphamide ; therapeutic use ; Humans ; Immunosuppressive Agents ; therapeutic use ; Middle Aged ; Mycophenolic Acid ; therapeutic use ; Neutrophils ; immunology ; Proportional Hazards Models ; Retrospective Studies