Elaine Tozman

BACKGROUND: Long-term therapy with cyclophosphamide enhances renal survival in patients with proliferative lupus nephritis; however, the beneficial effect of cyclophosphamide must be weighed against its considerable toxic effects. METHODS: Fifty-nine patients with lupus nephritis (12 in World Health Organization class III, 46 in class IV, and 1 in class Vb) received induction therapy consisting of a maximum of seven monthly boluses of intravenous cyclophosphamide (0.5 to 1.0 g per square meter of body-surface area) plus corticosteroids. Subsequently, the patients were randomly assigned to one of three maintenance therapies: quarterly intravenous injections of cyclophosphamide, oral azathioprine (1 to 3 mg per kilogram of body weight per day), or oral mycophenolate mofetil (500 to 3000 mg per day) for one to three years. The base-line characteristics of the three groups were similar, with the exception that the chronicity index was 1.9 points lower in the cyclophosphamide group than in the mycophenolate mofetil group (P=0.009). RESULTS: During maintenance therapy, five patients died (four in the cyclophosphamide group and one in the mycophenolate mofetil group), and chronic renal failure developed in five (three in the cyclophosphamide group and one each in the azathioprine and mycophenolate mofetil groups). The 72-month event-free survival rate for the composite end point of death or chronic renal failure was higher in the mycophenolate mofetil and azathioprine groups than in the cyclophosphamide group (P=0.05 and P=0.009, respectively). The rate of relapse-free survival was higher in the mycophenolate mofetil group than in the cyclophosphamide group (P=0.02). The incidence of hospitalization, amenorrhea, infections, nausea, and vomiting was significantly lower in the mycophenolate mofetil and azathioprine groups than in the cyclophosphamide group. CONCLUSIONS: For patients with proliferative lupus nephritis, short-term therapy with intravenous cyclophosphamide followed by maintenance therapy with mycophenolate mofetil or azathioprine appears to be more efficacious and safer than long-term therapy with intravenous cyclophosphamide.

The objective of this study was to identify the factors associated with important clinical outcomes in a case-control study of 213 patients with lupus nephritis. Included were 47% Hispanics, 44% African Americans and 9% Caucasians with a mean age of 28 years. Fifty-four (25%) patients reached the primary composite outcome of doubling serum creatinine, end-stage renal disease or death during a mean follow-up of 37 months. Thirty-four percent African Americans, 20% Hispanics and 10% Caucasians reached the primary composite outcome (P < 0.05). Patients reaching the composite outcome had predominantly proliferative lupus nephritis (WHO classes: 30% III, 32% IV, 18% V and 5% II, P < 0.025) with higher activity index score (7 +/- 6 versus 5 +/- 5, P < 0.05), chronicity index (CI) score (4 +/- 3 versus 2 +/- 2 unit, P < 0.025), higher baseline mean arterial pressure (MAP) (111 +/- 21 versus 102 +/- 14 mmHg, P < 0.025) and serum creatinine (1.9 +/- 1.3 versus 1.3 +/- 1.0 mg/dL, P < 0.025), but lower baseline hematocrit (29 +/- 6 versus 31 + 5%, P < 0.025) and complement C3 (54 +/- 26 versus 65 + 33 mg/dL, P < 0.025) compared to controls. More patients reaching the composite outcome had nephrotic range proteinuria compared to controls (74% versus 56%, P < 0.025). By multivariate analysis, CI (hazard ratio [95% CI] 1.18 [1.07-1.30] per point), MAP (HR 1.02 [1.00-1.03] per mmHg), and baseline serum creatinine (HR 1.26 [1.04-1.54] per mg/dL) were independently associated with the composite outcome. We concluded that hypertension and elevated serum creatinine at the time of the kidney biopsy as well as a high CI are associated with an increased the risk for chronic renal failure or death in patients with lupus nephritis.

Thrombocytopenia frequently complicates malarial infections but the mechanism has not been elucidated. We studied 28 patients with malarial infections and noted that 16 of 17 thrombocytopenic patients had elevated levels of platelet-associated IgG (PAIgG). In all thrombocytopenic patients studied, the level of PAIgG returned to normal as the platelet count rose to normal levels. To study the mechanism of the elevated platelet-bound IgG, IgG and F(ab')2 from patients with recurrent Plasmodium falciparum infections was purified and radiolabeled. Labeled and unlabeled P. falciparum antigen was also prepared. IgG did not nonspecifically bind to malaria-damaged platelets. Binding studies with 3H-malarial antigen demonstrated platelets have saturable binding sites for malarial antigen. Increasing concentrations of malarial antigen displaced the 125I-IgG antimalarial antibody from the platelets. The binding of 125I-IgG and 125I-F(ab')2 was similar and this excluded significant immune complex binding. The thrombocytopenia that complicates at least some malarial infections is caused by immune mechanisms; specific IgG binds to platelet-bound malaria antigen through the Fab portion of the immunoglobulin molecule.

For the treatment of proliferative lupus nephritis, long-term cyclophosphamide (CY) regimens are efficacious, however, at the expense of substantial toxicity. In the last decade, sequential regimens of short-term CY induction followed by either mycophenolate mofetil (MMF) or azathioprine (AZA) maintenance have shown to be efficacious and safe reducing the long-term exposure to CY. In a maintenance study including predominantly Hispanics and African-Americans, the patients who received MMF and AZA maintenance had a higher cumulative probability of remaining free of the composite of death or chronic renal failure (CRF) compared to quarterly intravenous CY (IVCY) maintenance (89% in MMF, 80%, in AZA and 45% in IVCY). Likewise, MMF and AZA maintenance were associated with significantly lower incidence of severe infections (2% in each MMF or AZA, and 25% in IVCY), sustained amenorrhea (6% in MMF, 8% in AZA, and 32% in IVCY), and hospitalizations (one hospital-days per patient-year in each MMF or AZA, and 10 in IVCY). In a European induction study including predominantly Caucasians, patients who received any of two sequential regimens, low dose versus high dose IVCY induction both followed by AZA maintenance, had a high cumulative probability of remaining free of treatment failure (84% in low dose IVCY and 80% in high dose IVCY; treatment failure defined as a composite of free of corticosteroid resistant flare, nephrotic syndrome, doubling creatinine, and persistent elevated creatinine). Low dose IVCY and high dose IVCY induction were associated with low incidence of sustained amenorrhea (4% in each group) and severe infections (11% in low dose and 22% in high dose IVCY induction). Of interest, most of the severe infection episodes occurred while patients were receiving IVCY induction. Finally an Asian study demonstrated that patients with proliferative lupus nephritis could be effectively treated with short-term oral CY induction followed by AZA maintenance. The cumulative probability of complete remission was 76%. The relapse rate was only 11%. The incidence of permanent amenorrhea and infection were 8% and 33%, respectively. None of the Asian patients had an increase in serum creatinine level to double the baseline value. Maintenance therapies with MMF or AZA following short-term CY induction in a sequential regimen are efficacious and safe for the treatment of high-risk patients with proliferative lupus nephritis.

For the treatment of proliferative lupus nephritis, long-term cyclophosphamide (CY) regimens are efficacious, however, at the expense of substantial toxicity. In the last decade, sequential regimens of short-term CY induction followed by either mycophenolate mofetil (MMF) or azathioprine (AZA) maintenance have shown to be efficacious and safe reducing the long-term exposure to CY. In a maintenance study including predominantly Hispanics and African-Americans, the patients who received MMF and AZA maintenance had a higher cumulative probability of remaining free of the composite of death or chronic renal failure (CRF) compared to quarterly intravenous CY (IVCY) maintenance (89% in MMF, 80%, in AZA and 45% in IVCY). Likewise, MMF and AZA maintenance were associated with significantly lower incidence of severe infections (2% in each MMF or AZA, and 25% in IVCY), sustained amenorrhea (6% in MMF, 8% in AZA, and 32% in IVCY), and hospitalizations (one hospital-days per patient-year in each MMF or AZA, and 10 in IVCY). In a European induction study including predominantly Caucasians, patients who received any of two sequential regimens, low dose versus high dose IVCY induction both followed by AZA maintenance, had a high cumulative probability of remaining free of treatment failure (84% in low dose IVCY and 80% in high dose IVCY; treatment failure defined as a composite of free of corticosteroid resistant flare, nephrotic syndrome, doubling creatinine, and persistent elevated creatinine). Low dose IVCY and high dose IVCY induction were associated with low incidence of sustained amenorrhea (4% in each group) and severe infections (11% in low dose and 22% in high dose IVCY induction). Of interest, most of the severe infection episodes occurred while patients were receiving IVCY induction. Finally an Asian study demonstrated that patients with proliferative lupus nephritis could be effectively treated with short-term oral CY induction followed by AZA maintenance. The cumulative probability of complete remission was 76%. The relapse rate was only 11%. The incidence of permanent amenorrhea and infection were 8% and 33%, respectively. None of the Asian patients had an increase in serum creatinine level to double the baseline value. Maintenance therapies with MMF or AZA following short-term CY induction in a sequential regimen are efficacious and safe for the treatment of high-risk patients with proliferative lupus nephritis.