Table 2 Comparison of baseline clinical features between group A (serum IgE level ≤ 60 KU/L) and group B (serum IgE level > 60 KU/L)

Gender (male, %)

39 (65.0%)

252 (63.2%)

0.782

Age at onset (mean ± SD)

51.2 ± 13.2

53.7 ± 12.8

0.152

Disease duration (months, median, IQR)

12 (4.25–36)

12 (4–36)

0.858

Allergic disease (n, %)

16 (26.7%)

185 (46.4%)

0.004**

Allergic disease family history (n, %)

7 (11.7%)

69 (17.3%)

0.274

Autoimmune disease family history (n, %)

4 (6.7%)

30 (7.5%)

0.814

Number of affected organs (median, IQR)

2 (2–4)

3 (2–5)

0.003**

IgG4-RD RI scores (mean ± SD)

9.3 ± 5.5

11.4 ± 5.2

0.002**

 Lacrimal gland

31 (51.7%)

202 (50.6%)

0.881

 Parotid gland

8 (13.3%)

65 (16.3%)

0.559

 Submandibular gland

23 (38.3%)

216 (54.1%)

0.022*

 Pancreas

18 (30.0%)

148 (43.7%)

0.048*

 Bile duct

9 (15.0%)

77 (19.3%)

0.426

 Retroperitoneal tissue

4 (6.7%)

69 (17.3%)

0.088

 Lung

17 (28.3%)

100 (25.1%)

0.588

 Kidney

7 (11.7%)

44 (11.0%)

0.883

 Lymph nodes

22 (36.7%)

188 (47.1%)

0.130

 Liver

2 (3.3%)

9 (2.3%)

0.611

 Paranasal sinus

16 (26.7%)

114 (28.6%)

0.760

 Thyroid

2 (3.3%)

11 (2.8%)

0.802

 Pituitary

2 (3.3%)

5 (1.3%)

0.229

 IgG4 (mg/L)

4680 (2195–13,700)

10,000 (4140–19,225)

0.003**

 IgG (g/L)

16.87 (13.34–21.06)

19.35 (14.93–25.91)

0.011*

 Eosinophils (10⁹/L)

0.15 (0.1–0.29)

0.23 (0.12–0.45)

0.014*

 ESR (mm/h)

14 (5.5–41.5)

22 (10–56.4)

0.023*

 CRP (mg/L)

1.13 (0.71–5.1)

2.17 (0.78–7.16)

0.081

 C3 (g/L)

0.98 (0.74–1.07)

0.93 (0.72–1.11)

0.994

 C4 (g/L)

0.18 (0.14–0.24)

0.16 (0.11–0.23)

0.060