1 Introduction
IgG4-related disease (IgG4-RD) is a condition in which the immune system
causes inflammation and the formation of masses in various organs,
including the pancreas and bile duct[1].
Nonetheless, encountering IgG4-RD involving the digestive system
(identified as IgG4-related gastrointestinal disease; IgG4-GID) is rare.
To date, a mere 19 instances of IgG4-GID manifesting as an isolated mass
in the stomach have been recorded in medical studies. This article
details the experience of a 44-year-old Asian male who received a
diagnosis of IgG4-GID that appeared as an solitary gastric mass. The
patient underwent surgery and showed no signs of recurrence six months
post-operation.
2 Case history /
examination
A 44-year-old Asian man was admitted to the hospital with chest
tightness, abdominal distension, and belching. The C13 breath test
yielded positive results, and a follow-up examination after 2 weeks of
quadruple anti-Helicobacter pylori treatment showed negative results.
Gastroscopy revealed a gastric mass(Figure 1).Endoscopic
Ultrasonography(EUS) identified a hypoechoic submucosal mass measuring
2.3x1.6cm in the gastric body, originating from the fourth layer, with
insufficient blood flow signal(Figure 2). Enhanced gastric Computer scan
confirmed the presence of the mass tumor growing both inside and outside
the gastric body,and other organs weren’t be involved. Gastric stromal
tumor was firstly considered as diagnosis and ectopic pancreas or
gastric lipoma was considered in the differential diagnosis.The patient
underwent endoscopic submucosal dissection (ESD), which revealed that
the tumor was adherent, unencapsulated, highly vascularized, and
difficult to remove so converted to laparoscopic surgery. Pathological
examination of the resected tissue showed submucosal nodular lesions
primarily located in the gastric submucosa and muscularis. The lesions
exhibited infiltration of IgG4-positive plasma cells (up to 80/HPF,
Figure 3) and more than 40% of IgG4+/IgG+ plasma cells (Figure 4).
Additionally, regional proliferation of vascular endothelium and
inflammatory cell infiltration of nerves was observed (Figure 5).These
pathological evidences pointed to IgG4-RD.
Other laboratory test results showed an elevated creatinine level of
107umol/L(normal is less than 97umol/l). However, the blood routine,
coagulation function, liver function, serum IgG4 level, tumor markers,
high-sensitivity C-reactive protein level, antinuclear antibodies,
antineutrophils Cytoplasmic antibodies, and immunoglobulin
G,immunoglobulin M and immunoglobulin A were all within normal
ranges.Additional laboratory test results indicated a raised creatinine
concentration, registering at 107umol/L(normal is less than 97umol/L).
Yet, other tests encompassing serum IgG4 were all within acceptable
limits. The food-intolerance IgG4 test showed that the serum IgG4 level
of eggs was higher than 1000 U/ml.