Table 1.

Background information on 23 patients with systemic lupus erythematosus and proliferative lupus nephritis and 21 matched controls without lupus nephritis

CharacteristicPatients with SLE and PLNControls with SLE without LN
Median age (yr)25 (23, 41)25 (23, 41)
Race (%)
 White1515
 African American6060
 Other2525
Women (%)6565
History of hypertension (%)83 (19/23)36
History of diabetes mellitus (%)0 (0/23)9
Arthralgia (%)70 (16/23)0
Dermatologic (%)48 (11/23)73
Hematologic (%)53 (12/23)46
Cardiac involvement (%)35 (8/23)41
CNS involvement (%)9 (2/23)23
Lung involvement (%)35 (8/23)9
Liver involvement (%)9 (2/23)5
Hematuria (>3 RBCs per high-power field)100 (23/23)
Proteinuria (>300 mg)100 (23/23)
Nephrotic-range proteinuria (>3.5 g)35 (8/23)
Median proteinuria (g)1.60 (0.63, 3.40)
Median serum creatinine (mg/dl)1.0 (0.8, 1.2)
Antinuclear antibody (% positive)96 (22/23)
dsDNA antibody (% positive)78 (18/23)
 Median titer (n=18)1:320 (1:160, 1:640)
 Median level (U/ml; n=6)200 (147, 228)
dsDNA antibody or antinuclear antibody (% positive)100 (23/23)
Antiphospholipid antibody (% positive)38 (8/23)
Anti-SM antibody (% positive)38 (6/16)
Anti-RNP antibody (% positive)50 (8/16)
Median CRP level (mg/dl)1.37 (0.83,3.88)
CRP level >0.8 mg/dl (%)79 (11/14)
Biopsy (%)
 WHO class III22 (5/23)
 WHO class IV78 (18/23)
 WHO class IV and V35 (8/23)
 Crescent formation23 (6/23)
Median NIH Activity Index8 (5, 10)
Median NIH Chronicity Index3 (1, 3)
Median SLE Disease Activity Index16 (12, 22)10 (4, 14)
Immunosuppression before biopsy (%)
 Prednisone22 (5/23)
 Hydroxychloroquine39 (9/23)
 Other (cyclophosphamide, mycophenolate mofetil, rituximab)9 (2/23)
  • Data on patients with lupus nephritis were based on review of electronic medical record charts. Data on controls without lupus nephritis are based on International Classification of Diseases, Ninth Revision, codes provided by the Department of Defense Serum Repository. Medians are presented with 25% and 75% values in parentheses for continuous data because they were not normally distributed. Prednisone dose was ≤10 mg/d. Some percentages are accompanied by n/n in parentheses. Other immunosuppression was discontinued at least 6 months before confirmatory kidney biopsy. Not all patients had information available for each laboratory measurement. Laboratory data were not available for the control patients. SLE, systemic lupus erythematosus; PLN, progressive lupus nephritis; LN, lupus nephritis; CNS, central nervous system; RBC, red blood cell; dsDNA, double-stranded DNA; SM, smooth muscle; RNP, ribonucleoprotein; CRP, C-reactive protein; NIH, National Institutes of Health.