Lupus Nephritis Diagnosis and Management

Diagnostic Features

Elevated creatinine indicates impaired glomerular filtration, a hallmark of lupus nephritis, with a level of 150 μmol/L in this patient 2
Severe hypoalbuminemia reflects nephrotic-range proteinuria, which is strongly associated with active lupus nephritis, with a level of 28 g/L in this patient 2
Low complement C3 and C4 are significantly associated with active renal disease in SLE, with levels of 0.5 g/L and 0.1 g/L, respectively, in this patient 2, 3
The combination of elevated creatinine, severe hypoalbuminemia, and low complement levels has established predictive value for kidney involvement and survival at 5 years 2
A 3-month progressive course is consistent with untreated or undertreated lupus nephritis 1

Quantify proteinuria with urine protein-to-creatinine ratio to confirm nephrotic-range proteinuria (>3.5 g/day) 1
Perform urine sediment analysis looking for red blood cell casts, white blood cell casts, or acanthocytes (≥5%) 1
Consider kidney biopsy to classify the lupus nephritis according to ISN/RPS criteria and guide immunosuppressive therapy 1, 5
Initial therapy should combine corticosteroids with either cyclophosphamide or mycophenolate mofetil (MMF) for proliferative lupus nephritis 1, 5
Hydroxychloroquine should be initiated unless contraindicated, as it reduces disease flares and improves outcomes 1
The risk of doubling serum creatinine is 7.4-8.5% at 5 years, emphasizing the need for aggressive early treatment 2, 4
Renal disease relapses are common (up to 45% of patients) and early aggressive treatment improves long-term kidney survival 2, 6