AISP - 29th National Congress. Bologna (Italy). September 15-17, 2005
JOP. J Pancreas (Online) 2004; 6(5 Suppl):482.

IgG Type 4 Are not Specific for Autoimmune Pancreatitis

Coato E, Frulloni L, Bernardoni L, Brunelli S, Vaona B, Bovo P, Faitini K, Bonzanini O, Prandelli C, Cavallini G

Department of Surgical and Gastroenterological Sciences, University of Verona. Verona, Italy

ABSTRACT

Background High serum levels of IgG type 4 (IgG4) have been proposed as a marker for the diagnosis of autoimmune pancreatitis (AIP).

Aim To evaluate whether the serum levels of IgG4 may be useful in the diagnosis of AIP.

Materials and methods We studied 27 patients suffering from AIP (13 males, 14 females, mean age 45.416 years). As control group, we studied 24 patients with a diagnosis of recurrent pancreatitis (RP), 46 of chronic pancreatitis (CP) and 34 of pancreatic cancer (PC). A commercial available immuno-nephelometric kit (Dade Behring, Marburg, Germany) was used to dose the serum levels of IgG and IgG subclasses. The normal serum IgG4 levels range in our laboratory from 0.07 to 0.64 g/L.

Results We observed an increase of serum levels of IgG4 subclass in patients suffering from autoimmune pancreatitis, but not statistically different from other groups of pancreatic diseases (Kruskal Wallis test) (Table: value are expressed as g/L).

 

AIP
(n=27)

RP
(n=24)

CP
(n=46)

PC
(n=34)

Total IgG

12.94.8

12.23.8

11.43.8

12.34.2

IgG I

7.73.1

7.22.2

6.72.3

7.63.4

IgG II

3.91.5

3.91.7

3.61.9

3.71.8

IgG III

0.510.3

0.530.3

0.510.3

0.540.3

IgG IV

0.841.2

0.560.5

0.640.6

0.610.5

We did not observe differences in serum levels of total IgG and IgG subclasses in the different groups of patients. Nine out of 27 patients in AIP group (33%), 9 out of 24 in RP group (38%), 16 out of 46 in CP group (35%) and 15 out of 34 in PC group (44%), had serum levels of IgG4 higher than the upper normal limit.

Conclusions These data do not support the use of IgG4 in the diagnosis of AIP in an Italian population.

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