Naoyuki Furuya

High Serum IgG4 Concentrations in Patients with Sclerosing Pancreatitis

BACKGROUND Sclerosing pancreatitis is a unique form of pancreatitis that is characterized by irregular narrowing of the main pancreatic duct, lymphoplasmacytic inflammation of the pancreas, and hypergammaglobulinemia and that responds to glucocorticoid treatment. Preliminary studies suggested that serum IgG4 concentrations are elevated in this disease but not in other diseases of the pancreas or biliary tract. METHODS We measured serum IgG4 concentrations using single radial immunodiffusion and an enzyme-linked immunosorbent assay in 20 patients with sclerosing pancreatitis, 20 age- and sex-matched normal subjects, and 154 patients with pancreatic cancer, ordinary chronic pancreatitis, primary biliary cirrhosis, primary sclerosing cholangitis, or Sjögrens syndrome. Serum concentrations of immune complexes and the IgG4 subclass of immune complexes were determined by means of an enzyme-linked immunosorbent assay with monoclonal rheumatoid factor. RESULTS The median serum IgG4 concentration in the patients with sclerosing pancreatitis was 663 mg per deciliter (5th and 95th percentiles, 136 and 1150), as compared with 51 mg per deciliter (5th and 95th percentiles, 15 and 128) in normal subjects (P<0.001). The serum IgG4 concentrations in the other groups of patients were similar to those in the normal subjects. In patients with sclerosing pancreatitis, serum concentrations of immune complexes and the IgG4 subclass of immune complexes were significantly higher before glucocorticoid therapy than after four weeks of such therapy. Glucocorticoid therapy induced clinical remissions and significantly decreased serum concentrations of IgG4, immune complexes, and the IgG4 subclass of immune complexes. CONCLUSIONS Patients with sclerosing pancreatitis have high serum IgG4 concentrations, providing a useful means of distinguishing this disorder from other diseases of the pancreas or biliary tract.

Characteristic pancreatic duct appearance in autoimmune chronic pancreatitis: A case report and review of the Japanese literature

We report a case demonstrating the progressive narrowing of the pancreatic duct, which is presumed to be characteristic of autoimmune pancreatitis, and we review the 37 cases of chronic pancreatitis in which autoimmunity was suggested as an etiological factor in the Japanese literature. A 55-year-old man presented with abdominal discomfort, jaundice, and diffuse swelling of the pancreas on ultrasonography. Serial endoscopic retrograde pancreatography demonstrated the progression of an irregular narrowing of the main pancreatic duct forming diffusely over the course of 2 months. Because the patient had hyperglobulinemia and tested positive for autoantibodies, he was diagnosed as a case of autoimmune chronic pancreatitis. Steroid therapy was carried out with excellent success.

Gastric schwannoma exhibiting increased fluorodeoxyglucose uptake.

This is the first case of gastric schwannoma that exhibited increased accumulation of [(18)F] fluorodeoxyglucose (FDG) on positron emission tomography (PET) imaging. The patient was a 60-year-old woman in whom esophagogastroduodenoscopy showed a submucosal tumor, about 25 mm in size, in the upper body of the stomach, with ulceration at the top of the tumor. Endoscopic ultrasonography revealed a well-defined hypoechoic mass located in the proper muscle layer of the stomach. The specimen taken from the tumor showed only inflammatory degenerative tissue. Abdominal computed tomography revealed a tumor in the upper body of the stomach. FDG-PET showed FDG uptake (standardized uptake value [SUV] max 5.8) coincident with the tumor. Hence, the tumor was diagnosed initially as a gastrointestinal stromal tumor of the stomach. Laparoscopic partial gastrectomy was performed. Pathological examination showed that the tumor consisted of spindle cells with large nuclei, and mitosis was absent. The Ki-67 labeling index of the tumor cells was 4%. Immunohistochemically, the tumor cells showed a positive reaction for S-100 protein, whereas they were negative for KIT, CD 34, and alpha-smooth muscle actin protein. The tumor was diagnosed as a benign gastric schwannoma. Gastric schwannoma should be included in the differential diagnosis of submucosal tumors of the stomach with FDG uptake.

Local Gastric and Serum Concentrations of Rebamipide Following Oral Ingestion in Healthy Volunteers

The purpose of this study was to investigate whether sufficient concentrations of rebamipide (COR) are actually present in the stomach after its oral ingestion at an ordinary clinical dose. Twenty healthy volunteers (total 42 man-days) participated in the study. After ingestion of 100, 200, or 300 mg of rebamipide, endoscopy was performed at 1, 2, 4, and 6 hr, and gastric mucosa or gastric mucus was taken from the antrum. Venous blood samples were taken simultaneously. Samples were analyzed by high-performance liquid chromatography. The COR in the gastric mucosa and gastric mucus did not depend on the original amount ingested. After ingestion of rebamipide, each COR was higher than 10−4 M(37 μg/g tissue) at 1 or 2 hr. On the other hand, the COR in serum did depend on the amount ingested and was lower than 10−6 M(0.37 μg/ml) at every time tested. These results suggest that the COR in the stomach exceeds the levels that are needed for various antiulcer actions and that the rebamipide levels present in the gastric mucosa and gastric mucus result from local penetration.

Comparative study of CA242 and CA19-9 in chronic pancreatitis

CA242 has been proved to be useful in the diagnosis of pancreatic cancer. The aim of the present study was to clarify the mechanisms contributing to the high specificity of CA242 as compared with CA19-9 resulting from scarce serum elevation of this antigen in patients with chronic pancreatitis by correlating serum levels and endoscopic retrograde choledocho-pancreatography (ERCP) findings and by immunohistochemical analysis. Serum CA19-9 levels were significantly elevated in patients with calcification and with main pancreatic duct (MPD) stenosis or obstruction. On the other hand, serum CA242 levels showed no significant elevation in patients with such factors. Even though such pathological conditions were considered to lead to the stagnation of pancreatic juice, serum CA242 levels seemed to be less affected than serum CA19-9 levels. Immunohistochemical studies of chronic pancreatitis tissues revealed that CA242 was expressed less frequently and less intensely than CA19-9, and the difference in expression was more prominent in the centroacinar cells and terminal ductules. From the results of the present study, it is conceivable that CA242 is less influenced by the stagnation of the pancreatic juice than CA19-9 because of the low levels of expression in ductal systems, which results in the release of this antigen into the circulation in lower amounts than that of CA19-9.