#2139 Non-lupus full house nephropathy: a debatable entity

Abstract Background and Aims The presence of a full house (FH) pattern at immunofluorescence on kidney biopsy in a patient without clinical and laboratory features of systemic lupus erythematosus (SLE) has led to the descriptive term non-lupus full house nephropathy (NLFHN). This systematic review and meta-analysis focus on NLFHN nomenclature, clinical findings and outcomes. Method In a reiterative process, all identified terms for NLFHN and other MeSH terms were searched in PubMed. Out of 344 results, 57 records published between 1982 and 2022 were included in the analysis. Clinical data of single patients from different reports were collected and analysed. Results Out of the 57 records, 61% were case reports. NLFHN was addressed with 17 different names; the same name used by different authors could refer to different entities. We identified 148 patients: 75 (51%) were males; median age 35 (23-58) years. Serum creatinine and proteinuria at onset were 1.4 (0.8-2.5)mg/dL and 5.7 (2.7-8.8)g/day. Overall, about half of patients achieved complete response. A causative agent was identified in 51 (44%) patients, predominantly infections(41%). Secondary NLFHN was mostly non-relapsing with worse kidney function at onset compared to idiopathic NLFHN (P = 0.001). Among the 57 (50%) patients with idiopathic NLFHN, complete response was comparable between patients treated with immunosuppression and supportive therapy; however, proteinuria and creatinine at onset were higher in patients treated with immunosuppression (P = 0.089 and P = 0.066). The remaining 7 (6%) patients developed SLE after a median follow-up of 5.0 (1.9-9.0) years. Conclusion The place of NLFHN among glomerular diseases is still uncertain, due to the lack of high-quality evidence and consensus on nomenclature. NLFHN can be evaluated as initial manifestation of SLE, isolated manifestation of SLE or a new disease unrelated to SLE. Data support the classification of SLE and NLFHN as distinct clinical entities, with comparable outcome. However, RCTs are needed to drive strong conclusions on treatments and outcomes.