Immunofluorescence-based reclassification of idiopathic membranoproliferative glomerulonephritis: Insights from a single-center cohort

Table 1 Comparison of baseline demographic, clinical, and laboratory features by immunofluorescence classification, median (interquartile rage)/n (%)/mean ± SD

	IC-MPGN (n = 100)	C-MPGN (n = 28)	P value
Age at biopsy (years)	33.5 (22-45)	38 (28.3-53)	0.029
Gender			0.978
Male	64 (64.0)	18 (64.3)
Female	36 (36.0)	10 (35.7)
Blood pressure (mmHg)
Systolic	150 (135-160)	145 (139.2-159)	0.394
Diastolic	93.5 (80.5-100)	89 (80-100)	0.293
First clinical manifestation			0.298
Nephrotic syndrome	34 (34)	10 (35.7)
Acute GN	53 (53)	16 (57.1)
RPGN	13 (13)	2 (7.1)
Microscopic hematuria			0.018
< 2 (trace)	8 (8)	7 (25)
2-4 (+1)	17 (17)	3 (10.7)
5-10 (+2)	10 (10)	6 (21.4)
≥ 11 (+3)	65 (65)	12 (42.9)
Proteinuria (dipstick)			0.760
Trace	1 (1)	0 (0)
+1	3 (3)	0 (0)
+2	10 (10)	2 (7.1)
+3	65 (65)	18 (64.3)
+4	21 (21)	8 (28.6)
Serum creatinine (mg/dL)	2.25 (1.6-3.7)	2.55 (1.6-5.3)	0.537
eGFR (ml/minute/1.73 m2)	62.6 (40-108)	57 (20-99.8)	0.208
Total serum protein (g/dL)	5.37 ± 1.03	5.88 ± 0.99	0.020
Serum albumin (g/dL)	2.40 ± 0.60	2.68 ± 0.70	0.036
Serum C3 levels			0.084
Low (< 0.8 g/L)	65 (65)	23 (82.1)
Normal (> 0.8 g/L)	35 (35)	5 (17.9)
Serum C4 levels			0.965
Low (< 0.16 g/L)	29 (29)	8 (28.6)
Normal (> 0.16 g/L)	71 (70)	20 (71.4)
24 hours urinary protein (g/day)	3.1 (2-4.4)	3.01 (2-4.9)	0.753

Continuous variables were compared using the Mann-Whitney U test (or Student’s t-test for normally distributed data). Categorical variables were analyzed using χ² or Fisher’s exact test, as appropriate. GN: Glomerulonephritis; RPGN: Rapidly progressive glomerulonephritis; eGFR: Estimated glomerular filtration rate; IC-MPGN: Immune complex-mediated membranoproliferative glomerulonephritis; C-MPGN: Complement-mediated membranoproliferative glomerulonephritis.