Association between autoimmune pancreatitis and systemic autoimmune diseases.
OBJECTIVE
To investigate the association between autoimmune pancreatitis (AIP) and systemic autoimmune diseases (SAIDs) by measurement of serum immunoglobulin G4 (IgG4).


METHODS
The serum level of IgG4 was measured in 61 patients with SAIDs of different types who had not yet participated in glucocorticosteroid treatment. Patients with an elevated IgG4 level were examined by abdominal ultrasonography (US) and, in some cases, by computer tomography (CT).


RESULTS
Elevated serum IgG4 levels (919 ± 996 mg/L) were detected in 17 (28%) of the 61 SAID patients. 10 patients had Sjögren's syndrome (SS) (IgG4: 590 ± 232 mg/L), 2 of them in association with Hashimoto's thyroiditis, and 7 patients (IgG4: 1388 ± 985.5 mg/L) had systemic lupus erythematosus (SLE). The IgG4 level in the SLE patients and that in patients with SS were not significantly different from that in AIP patients (783 ± 522 mg/L). Abdominal US and CT did not reveal any characteristic features of AIP among the SAID patients with an elevated IgG4 level.


CONCLUSIONS
The serum IgG4 level may be elevated in SAIDs without the presence of AIP. The determination of serum IgG4 does not seem to be suitable for the differentiation between IgG4-related diseases and SAIDs.
First Department of Medicine, University of Szeged, H-6701 Szeged, Hungary.
Viktória
V
Terzin
Imre
I
Földesi
László
L
Kovács
Gyula
G
Pokorny
Tibor
T
Wittmann
László
L
Czakó
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001327:Autoimmune Diseases / Q000097:blood / Q000150:complications* / Q000276:immunology*; D005260:Female; D050031:Hashimoto Disease / Q000150:complications / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008180:Lupus Erythematosus, Systemic / Q000150:complications / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010195:Pancreatitis / Q000097:blood / Q000150:complications* / Q000276:immunology*; D010865:Pilot Projects; D012859:Sjogren's Syndrome / Q000150:complications / Q000276:immunology; D014057:Tomography, X-Ray Computed / Q000379:methods; D014463:Ultrasonography / Q000379:methods
D007074:Immunoglobulin G