Renal-Limited "Lupus-Like" Nephritis: How Much of a Lupus?

Treatment of HIV-Associated Lupus-like Membranous Nephropathy with Tacrolimus: A Case Report and Review of the Literature

Renal complications of HIV infection are common and histologically diverse. Besides HIV-associated nephropathy, which is the most well-defined glomerular disorder, immune-complex-mediated glomerulonephritis (HIVICK) is also encountered in the setting of HIV infection and may occasionally present with “lupus-like” features by light microscopy and immunofluorescence. Management of HIVICK remains controversial and mainly focuses on HIV viremia suppression with combined antiretroviral therapy. Immunosuppressive therapy may be used in order to mitigate the renal inflammation induced by the immune complex deposition. Data regarding the use of immunosuppressants in HIVICK are very limited, mostly including corticosteroids and mycophenolate acid analogues. Herein, we present the case of a 40-year-old HIV-infected Caucasian man with nephrotic syndrome, renal impairment, and a “lupus-like” membranous pattern in the kidney biopsy, who achieved a partial response of his proteinuria with a tacrolimus-based regimen in combination with antiretroviral therapy.

Seronegative Full-house Nephropathy with Crohn's Disease

Systemic lupus erythematosus (SLE) is a chronic autoimmune inflammatory disease. Lupus nephritis (LN) is a major risk factor for mortality in SLE, and glomerular "full-house" immunofluorescence staining is a well-known characteristic of LN. However, some cases of non-lupus glomerulonephritis can also present with a "full-house" immunofluorescence pattern. We recently encountered a patient with full-house nephropathy (FHN) during adalimumab administration for Crohn's disease. IgA nephropathy or idiopathic FHN was diagnosed, and treatment with steroids was started, after which there was improvement in proteinuria. The prognosis of FHN has been reported to be poor; therefore, aggressive treatment is required for such patients.

Lupus-like membranous nephropathy. Is it lupus? Report of 5 cases in a reference hospital in Mexico

INTRODUCTION

Lupus nephritis requires antinuclear antibodies as classification criteria. There is a group of patients with nephrotic syndrome and conclusive histopathological findings for lupus nephritis, without classification criteria for systemic lupus erythematosus (SLE) or extrarenal manifestations. These groups of patients have been described as "lupus-like" nephritis or "renal-limited lupus nephritis".

METHODS

Renal biopsy with histopathological evaluation with "full-house" immune-reactants in patients with negative antinuclear antibodies.

RESULTS

We report four cases with nephrotic syndrome and one with hematuria-proteinuria syndrome: two with impaired glomerular filtration rate and three with preserved renal function; urinary sediment with hematuria without dysmorphia and without extrarenal manifestations for autoimmune disease, negative antinuclear antibodies (ANA) and anti-double stranded DNA (anti-dsDNA); normal C3 and C4 complement levels. Renal biopsy in all cases was consistent for lupus nephritis class V. All patients received treatment as lupus nephritis protocol; only one case received induction with cyclophosphamide and methylprednisolone boluses, the rest received mycophenolic acid and prednisone as induction and maintenance. Two of the cases induced with mycophenolic acid relapsed, requiring cyclophosphamide for 6 months, achieving complete remission. All patients received renin-angiotensin-aldosterone system blockade and hydroxychloroquine. At follow-up, 4 cases still have negative antibodies and are without extrarenal manifestations for SLE classification criteria. The other case, during pregnancy several years after initial diagnosis, had preeclampsia with nephrotic proteinuria and a new determination of positive ANA and anti-dsDNA antibodies, complement levels below normal limits.

CONCLUSION

The follow-up of patients with membranous glomerulopathy must be close; lupus like nephritis may be the first manifestation of the disease.

Sensitivity and Specificity of Pathologic Findings to Diagnose Lupus Nephritis

BACKGROUND AND OBJECTIVES

In 2012, the Systemic Lupus International Collaborating Clinics proposed that lupus nephritis, in the presence of positive ANA or anti-dsDNA antibody, is sufficient to diagnose SLE. However, this "stand-alone" kidney biopsy criterion is problematic because the ISN/RPS classification does not specifically define lupus nephritis. We investigated the combination of pathologic features with optimal sensitivity and specificity for the diagnosis of lupus nephritis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Three hundred consecutive biopsies with lupus nephritis and 560 contemporaneous biopsies with nonlupus glomerulopathies were compared. Lupus nephritis was diagnosed if there was a clinical diagnosis of SLE and kidney biopsy revealed findings compatible with lupus nephritis. The control group consisted of consecutives biopsies showing diverse glomerulopathies from patients without SLE, including IgA nephropathy, membranous glomerulopathy, pauci-immune glomerulonephritis, membranoproliferative glomerulonephritis (excluding C3 GN), and infection-related glomerulonephritis. Sensitivity and specificity of individual pathologic features and combinations of features were computed.

RESULTS

Five characteristic features of lupus nephritis were identified: "full-house" staining by immunofluorescence, intense C1q staining, extraglomerular deposits, combined subendothelial and subepithelial deposits, and endothelial tubuloreticular inclusions, each with sensitivity ranging from 0.68 to 0.80 and specificity from 0.8 to 0.96. The presence of at least two, three, or four of the five criteria had a sensitivity of 0.92, 0.8, and 0.66 for the diagnosis of lupus nephritis, and a specificity of 0.89, 0.95, and 0.98.

CONCLUSIONS

In conclusion, combinations of pathologic features can distinguish lupus nephritis from nonlupus glomerulopathies with high specificity and varying sensitivity. Even with stringent criteria, however, rare examples of nonlupus glomerulopathies may exhibit characteristic features of lupus nephritis.