Successful treatment of patients with lipoprotein glomerulopathy by protein A immunoadsorption: a pilot study.

BACKGROUND No established therapy is available for patients with lipoprotein glomerulopathy (LPG). Protein A immunoadsorption has been proved to be effective in reducing proteinuria in patients with nephrotic syndrome. In this uncontrolled pilot study, we investigated the efficiency of immunoadsorption onto staphylococcal protein A as treatment for LPG. METHODS Thirteen patients with renal biopsy-proven LPG were treated with staphylococcal protein A immunoadsorption. Immunoadsorption was administered for 10 cycles per session and 10 sessions as a course. A total of 30 l of plasma was regenerated in each course. RESULTS Single immunoadsorption course led to a rapid decline in proteinuria from 4.01 +/- 3.09 g/24 h to 1.21 +/- 0.97 g/24 h (mean +/- SD) (n = 13, P = 0.001), along with a dramatic decline in apolipoprotein E (apo E) from 9.79 +/- 5.04 mg/dl to 6.20 +/- 2.22 mg/dl (P = 0.004). A repeated renal biopsy (n = 12) showed that intraglomerular lipoprotein thrombi almost disappeared. Six patients were enrolled in the investigation of long-term outcome, and proteinuria returned to baseline levels within 12 months. Four recurrent patients received repeat immunoadsorption treatment; proteinuria decreased from 5.02 +/- 1.85 g/24 h to 1.64 +/- 0.55 g/24 h at the end of the treatment, serum apo E decreased from 14.65 +/- 11.17 mg/dl to 7.90 +/- 1.72 mg/dl. No patients suffered from severe complications. CONCLUSION Our observations suggest that immunoadsorption onto protein A might be an effective treatment for resolving intraglomerular thrombi and improving nephrotic syndrome in patients with LPG. Further studies are required to define the influence of immunoadsorption on long-term effects in LPG patients.