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Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by development of autoantibodies to nuclear and cytoplasmic antigens. A small subset of SLE patients who had the typical clinical features of SLE was reported to show persistently negative antinuclear antibody tests. Our report describes a 5-year-old male who presented with histopathological findings suggestive of lupus nephritis with no clinical signs or symptoms of SLE and negative autoantibodies. He was treated with corticosteroids, mycophenolate mofetil, and monthly intravenous cyclophosphamide. During the 2-year follow-up period, the proteinuria resolved and kidney function improved with continued negative autoantibody workup. This case presents a category of renal-limited “lupus-like” glomerulonephritis which can be challenging to treat and carries a poor prognosis.

Tubuloreticular inclusions (TRIs) are subcellular structures located within the cisternae of endoplasmic reticulum. Formation of TRIs has been linked to the exposure of excess interferon (IFN), either from endogenous or exogenous sources. In renal disease, TRIs have been most commonly associated with systemic lupus erythematosus (SLE), and human immunodeficiency virus-associated nephropathy (HIVAN). Case reports of patients with renal biopsies showing TRIs without underlying SLE or HIV are infrequent in adults, and to our knowledge none have been reported in children. We report 3 pediatric cases in which the renal biopsy showed TRIs on electron microscopy without underlying SLE or HIV infection. The first patient presented at 2 years of age with nephrotic syndrome and renal failure. His renal biopsy revealed focal segmental glomerulosclerosis and TRIs. The second patient presented at 6 months of age with infantile nephrotic syndrome, and his renal biopsy revealed membranous glomerulopathy and TRIs. The last patient presented at 4 years of age with acute kidney injury of unclear etiology leading to chronic kidney disease. Her biopsy revealed acute and chronic tubulointerstitial nephritis with TRIs. Despite extensive evaluation in all 3 patients, including testing for HIV infection and SLE, we could not identify an underlying etiology to explain the presence of TRIs. In conclusion, renal biopsy with TRIs in the absence of underling SLE and HIV remains obscure. We propose a possible role for excess IFN triggered by an abnormal immune response to common viral infections in the formation of TRIs and renal injury.