Clinical–Morphological Features and Outcomes of Lupus Podocytopathy

Abstract

Background and objectives Lupus podocytopathy, which is characterized by diffuse foot process effacement without peripheral capillary wall immune deposits and glomerular proliferation, has been described in SLE patients with nephrotic syndrome in case reports and small series. This study aimed to better characterize the incidence, clinical-morphologic features, and outcomes of such patients from a large Chinese cohort.Design, setting, participants, & measurements Lupus podocytopathy was identified from 3750 biopsies of SLE patients obtained from 2000 to 2013 that showed mild glomerular histology in patients with a clinical sign of nephrotic syndrome. The biopsy results were divided into three groups: glomerular minimal change, mesangial proliferation, and FSGS.Results Fifty (1.33%) cases were identified as lupus podocytopathy and included minimal change in 13 cases, mesangial proliferation in 28 cases, and FSGS in nine cases. Extensive foot process effacement appeared in all the biopsies and mesangial electron-dense deposits were present in 47 biopsies. All patients demonstrated nephrotic syndrome, and the median proteinuria was 5.72 g/24 h (interquartile range [IQR], 3.82, 6.92). Seventeen (34%) cases presented with AKI. Forty-seven (94%) patients achieved remission after immunosuppressive therapy for a median time of 4 weeks (IQR,2,8). Compared with the patients with minimal change and mesangial proliferation, patients with FSGS showed significantly higher incidence of AKI and severe tubule-interstitial injury and a much lower complete remission rate. During follow-up of a median of 62 (IQR, 36, 84) months, renal relapses occurred in 28 (59.6%) patients. No patient died or developed ESRD. ConclusionsThe findings from this cohort study suggest that lupus podocytopathy may represent a special entity of lupus nephritis with distinct clinical-morphologic features. The differences in AKI incidence, tubular injury severity, and response to treatment between the patients with minimal change/mesangial proliferation and those with FSGS patterns indicate two different subtypes of lupus podocytopathy.

Recurrent podocytopathy in a patient with systemic lupus erythematosus

“…1 Immune deposits were present only in the mesangium of our patient as is found in most SLE patients. There were no capillary wall deposits on EM and podocyte foot process effacement was extensive/subtotal.…”

Update on Lupus Nephritis

“…Although immune-complex-mediated GN is the most common cause of kidney disease in SLE, there are other mechanisms that result in renal injury which can only be diagnosed with a biopsy, and require a different approach to management than immune-complex LN. Examples include thrombotic microangiopathy and lupus podocytopathy (defined as nephrotic syndrome in SLE that on kidney biopsy shows diffuse foot process effacement and no subendothelial or subepithelial immune deposits), which can be seen in up to 24% and 1.3% of LN patients, respectively (50,51). The finding of isolated tubulointerstitial nephritis is rare (52).…”

Lupus nephritis: When and how often to biopsy and what does it mean?

“…The few patients with class II and nephrotic syndrome, should be treated with high doses of corticosteroids (0.5e1 mg/kg/ day) for 1 month and then gradually tapered. The association of corticosteroids and immunosuppressive drugs is reported to be of benefit in non responsive patients [55].…”