Autori: A. Cappoli1, I. Umbro2, F. Fiacco1, A. Zavatto1, B. Cerbelli2,, G. D’Amati2, L. Dello Strologo3, A.P. Mitterhofer1
Affiliazioni: 1. Department of Clinical Medicine, 2. Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, Policlinico Umberto I, Sapienza, University of Rome, 3. Ospedale Pediatrico Bambino Gesù
INTRODUCTION: Full house nephropathy (FHN) is a term recently used to define histologic lesions similar to those found in lupus nephropathy (LN) with a full-house immunofluorescence pattern, characterized by a positive staining for IgG, IgA, IgM, C3 and C1q, in patients without serum autoantibodies and other signs or symptoms of systemic lupus erythematosus (SLE). Non-lupus FHN can be idiopathic or secondary to other renal diseases. Idiopathic FHN is usually characterized by erythrocyturia, proteinuria, often in nephrotic range, with complement consumption. There are only few observational studies in literature and only a minority of patients develop lupus autoantibodies or clinical symptoms of systemic lupus erythematosus.
Positive stain for IgG
Here we describe the case of a now 30 years old woman who presented with increased serum creatinine (sCr) and proteinuria in 1992 at the age of 11. Kidney biopsy showed diffuse proliferative glomerulonephritis with a full-house immunoflourescence pattern. Despite lupus serology was negative and she had no other signs other than renal involvement, she was treated with steroid pulses and cyclophosphamide without results. In 1995 she underwent a kidney transplantation. During follow-up renal function was normal with sCr around 0.8 mg/dL until February 2015. In 2003 she was diagnosed with plasmocitoma-like PTLD and was treated with reduction of immunosuppressors and chemiotheraphy with R-CHOP. In 2015 she had a biopsy-proven relapse of PTLD treated with Rituximab. During immunotheraphy we observed a progressive increase of sCr up to 5 mg/dL with nephrotic range proteninuria, consumption of C3 (800 mg/dL) and microhematuria. A biopsy of the transplanted kidney showed diffuse glomerulosclerosis, one fibrocellular crescent and positive staining for IgG, IgA, IgM, C3, C1q, kappa and lambda chains. Lupus serology was still negative.
Positive stain for C3
CONCLUSION: As proven by biopsy of the transplanted kidney this is the first case describing a relapse of FHN after kidney transplantation. FHN is a pattern of kidney damage often observed in LN, but it may also be idiophatic, as in this case. In literature few cases of idiopathic FHN are described. Currently we can’t say if the relapse in our patient is due to discontinuation of immunosuppressors secondary to PTLD. Lupus serology has always been negative, although the patient was always under immunosuppressors. The pathogenesis of idiopathic non-lupus FHN is still unknown, as well as therapeutic strategies.
Positive stain for lambda chains
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