Pediatric Non-Lupus Full House Nephropathy: Case Report and Review of Literature.

Lupus nephritis is a severe manifestation of systemic lupus erythematosus (SLE) typically characterized by glomerular "full-house" immunofluorescence. However, non-lupus nephropathies may occasionally exhibit similar patterns, creating diagnostic uncertainty. Non-lupus full-house nephropathy (FHN) is a recently recognized entity in which a full-house immunofluorescence pattern occurs in the absence of serological or clinical evidence of SLE. We report a 4-year-old girl who presented with generalized edema, hematuria, hypertension, and nephrotic-range proteinuria. Laboratory evaluation revealed anemia, elevated serum creatinine, and low complement C3 levels but negative antinuclear antibody (ANA) and anti-double-stranded DNA (anti-dsDNA) tests. Renal biopsy demonstrated diffuse proliferative glomerulonephritis consistent with lupus nephritis Class IV, with full-house immunofluorescence positivity for IgG, IgA, IgM, C3, and C1q. In the absence of systemic or serologic lupus features, a diagnosis of non-lupus full-house nephropathy was made. The patient was treated with pulse methylprednisolone followed by oral prednisolone, monthly cyclophosphamide for 6 months, and maintenance therapy with azathioprine and low-dose steroids. Hydroxychloroquine and antihypertensive agents were added. She achieved clinical and biochemical remission on follow-up.