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Detection of serum IgG4 levels in patients with IgG4-related disease and other disorders.

Su Y, Sun W, Wang C, Wu X, Miao Y, Xiong H, Bai L, Dong L - PLoS ONE (2015)

Bottom Line: High levels of IgG4 were observed in IgG4-RD.However, this phenomenon could also be observed in other diseases, such as carcinomas and other autoimmune diseases.Thus, a diagnosis of IgG4 disease cannot only be dependent on the detection of elevated serum IgG4 levels.

View Article: PubMed Central - PubMed

Affiliation: Department of Rheumatology and Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.

ABSTRACT

Objective: Elevated serum IgG4 levels are an important hallmark for diagnosing IgG4-related disease (IgG4-RD), but can also be observed in other diseases. This study aimed to compare two different testing methods for IgG4: ELISA and nephelometric assay. Both assays were used to measure serum IgG4 concentrations, and to assess the prevalence of high serum IgG4 levels in both IgG4-RD and non-IgG4-RD diseases.

Methods: A total of 80 serum samples were tested using the nephelometric assay and ELISA method that we established. Serum IgG4 concentrations were determined by ELISA for 957 patients with distinct diseases, including 12 cases of IgG4-RD and 945 cases of non-IgG4-RD.

Results: IgG4 levels from 80 selected serum samples examined by ELISA were in agreement with those detected using the nephelometry assay. Meanwhile, the serum IgG4 concentrations measured by ELISA were also consistent with the clinical diagnoses of patients with IgG4-RD during the course of disease. The Elevated levels of serum IgG4 (>1.35 g/L) were detected in all IgG4-RD (12/12) patients, and the prevalence of high IgG4 serum levels was 3.39% in non-IgG4-RD cases. Among them, the positive rates of serum IgG4 were 2.06% in patients with carcinoma and 6.3% in patients with other non-IgG4 autoimmune diseases.

Conclusion: Our established ELISA method is a reliable and convenient technique, which could be extensively used in the clinic to measure serum IgG4 levels. High levels of IgG4 were observed in IgG4-RD. However, this phenomenon could also be observed in other diseases, such as carcinomas and other autoimmune diseases. Thus, a diagnosis of IgG4 disease cannot only be dependent on the detection of elevated serum IgG4 levels.

No MeSH data available.


Related in: MedlinePlus

Serum IgG4 levels in patients with different types of tumors.(mean±SD = 0.48±0.49g/L vs. 0.40±0.31g/L vs. 0.40±0.29g/L vs. 0.43±0.39g/L vs. 0.51±0.69g/L vs. 0.57±0.69g/L vs. 0.49±0.38g/L vs. 0.44±0.35g/L vs. 0.42±0.26g/L vs. 0.35±0.37g/L vs. 0.58±0.36g/L vs. 0.55±0.46g/L vs. 0.40±0.25g/L vs. 0.30±0.32g/L vs. 0.31±0.34g/L vs. 0.47±0.37g/L).
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pone.0124233.g004: Serum IgG4 levels in patients with different types of tumors.(mean±SD = 0.48±0.49g/L vs. 0.40±0.31g/L vs. 0.40±0.29g/L vs. 0.43±0.39g/L vs. 0.51±0.69g/L vs. 0.57±0.69g/L vs. 0.49±0.38g/L vs. 0.44±0.35g/L vs. 0.42±0.26g/L vs. 0.35±0.37g/L vs. 0.58±0.36g/L vs. 0.55±0.46g/L vs. 0.40±0.25g/L vs. 0.30±0.32g/L vs. 0.31±0.34g/L vs. 0.47±0.37g/L).

Mentions: Unexpectedly, the highest positive rate of serum IgG4 levels in non-IgG4-RD was 8.33% in neurological disorders,which represented 2 patients with cerebral infarction. The second highest group in this study was 6.67% of patients with digestive diseases, including 3 patients with cirrhosis and 1 with colon polyps. The positive rate of serum IgG4 concentrations in other autoimmune diseases was 6.3%, including 2 patients with ankylosing spondylitis, 2 patients with rheumatoid arthritis, 3 patients with myositis, and 1 patient with suspected connective disease who had elevated serum IgG4 levels (>1.35 g/L). Instead, the positive rate of serum IgG4 in carcinoma was 2.06%, as elevated serum IgG4 levels were determined in 2 lung carcinoma cases (1.39 and 3.84 g/L), 2 rectal carcinoma cases (1.58 and 3.8 g/L), 1 hepatoma case (2.13 g/L), 1 gallbladder carcinoma case (1.63 g/L), 1 cholangiocarcinoma case (2.85 g/L), 1 penile cancer case (1.54 g/L), 2 Acute Myelocytic Leukemia cases (1.36 g/L, 2.49 g/L), and 1 left elbow pleomorphic undifferentiated sarcoma case (1.435 g/L) (Table 2 and Fig 4). Other non-IgG4-RD, such as respiratory disorders and hematological diseases, had a low false positive rate of serum IgG4, ranging from 1.25% to 2.63%. Moreover, no patients with high levels of IgG4 (>1.35 g/L) were found among infectious diseases patients, especially among pulmonary infection and cardiovascular disorder cases (Table 1). Although the cardiovascular system can be involved in IgG4-RD, as reported in the literature, there were no patients with cardiovascular disease who exhibited high serum IgG4 concentrations in our cohort, so we speculate that cardiovascular involvement in IgG4-RD is rare. Our observation of serum IgG4 levels in non-IgG4-RD will help us make a better differential diagnosis in the clinic.


Detection of serum IgG4 levels in patients with IgG4-related disease and other disorders.

Su Y, Sun W, Wang C, Wu X, Miao Y, Xiong H, Bai L, Dong L - PLoS ONE (2015)

Serum IgG4 levels in patients with different types of tumors.(mean±SD = 0.48±0.49g/L vs. 0.40±0.31g/L vs. 0.40±0.29g/L vs. 0.43±0.39g/L vs. 0.51±0.69g/L vs. 0.57±0.69g/L vs. 0.49±0.38g/L vs. 0.44±0.35g/L vs. 0.42±0.26g/L vs. 0.35±0.37g/L vs. 0.58±0.36g/L vs. 0.55±0.46g/L vs. 0.40±0.25g/L vs. 0.30±0.32g/L vs. 0.31±0.34g/L vs. 0.47±0.37g/L).
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4401680&req=5

pone.0124233.g004: Serum IgG4 levels in patients with different types of tumors.(mean±SD = 0.48±0.49g/L vs. 0.40±0.31g/L vs. 0.40±0.29g/L vs. 0.43±0.39g/L vs. 0.51±0.69g/L vs. 0.57±0.69g/L vs. 0.49±0.38g/L vs. 0.44±0.35g/L vs. 0.42±0.26g/L vs. 0.35±0.37g/L vs. 0.58±0.36g/L vs. 0.55±0.46g/L vs. 0.40±0.25g/L vs. 0.30±0.32g/L vs. 0.31±0.34g/L vs. 0.47±0.37g/L).
Mentions: Unexpectedly, the highest positive rate of serum IgG4 levels in non-IgG4-RD was 8.33% in neurological disorders,which represented 2 patients with cerebral infarction. The second highest group in this study was 6.67% of patients with digestive diseases, including 3 patients with cirrhosis and 1 with colon polyps. The positive rate of serum IgG4 concentrations in other autoimmune diseases was 6.3%, including 2 patients with ankylosing spondylitis, 2 patients with rheumatoid arthritis, 3 patients with myositis, and 1 patient with suspected connective disease who had elevated serum IgG4 levels (>1.35 g/L). Instead, the positive rate of serum IgG4 in carcinoma was 2.06%, as elevated serum IgG4 levels were determined in 2 lung carcinoma cases (1.39 and 3.84 g/L), 2 rectal carcinoma cases (1.58 and 3.8 g/L), 1 hepatoma case (2.13 g/L), 1 gallbladder carcinoma case (1.63 g/L), 1 cholangiocarcinoma case (2.85 g/L), 1 penile cancer case (1.54 g/L), 2 Acute Myelocytic Leukemia cases (1.36 g/L, 2.49 g/L), and 1 left elbow pleomorphic undifferentiated sarcoma case (1.435 g/L) (Table 2 and Fig 4). Other non-IgG4-RD, such as respiratory disorders and hematological diseases, had a low false positive rate of serum IgG4, ranging from 1.25% to 2.63%. Moreover, no patients with high levels of IgG4 (>1.35 g/L) were found among infectious diseases patients, especially among pulmonary infection and cardiovascular disorder cases (Table 1). Although the cardiovascular system can be involved in IgG4-RD, as reported in the literature, there were no patients with cardiovascular disease who exhibited high serum IgG4 concentrations in our cohort, so we speculate that cardiovascular involvement in IgG4-RD is rare. Our observation of serum IgG4 levels in non-IgG4-RD will help us make a better differential diagnosis in the clinic.

Bottom Line: High levels of IgG4 were observed in IgG4-RD.However, this phenomenon could also be observed in other diseases, such as carcinomas and other autoimmune diseases.Thus, a diagnosis of IgG4 disease cannot only be dependent on the detection of elevated serum IgG4 levels.

View Article: PubMed Central - PubMed

Affiliation: Department of Rheumatology and Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.

ABSTRACT

Objective: Elevated serum IgG4 levels are an important hallmark for diagnosing IgG4-related disease (IgG4-RD), but can also be observed in other diseases. This study aimed to compare two different testing methods for IgG4: ELISA and nephelometric assay. Both assays were used to measure serum IgG4 concentrations, and to assess the prevalence of high serum IgG4 levels in both IgG4-RD and non-IgG4-RD diseases.

Methods: A total of 80 serum samples were tested using the nephelometric assay and ELISA method that we established. Serum IgG4 concentrations were determined by ELISA for 957 patients with distinct diseases, including 12 cases of IgG4-RD and 945 cases of non-IgG4-RD.

Results: IgG4 levels from 80 selected serum samples examined by ELISA were in agreement with those detected using the nephelometry assay. Meanwhile, the serum IgG4 concentrations measured by ELISA were also consistent with the clinical diagnoses of patients with IgG4-RD during the course of disease. The Elevated levels of serum IgG4 (>1.35 g/L) were detected in all IgG4-RD (12/12) patients, and the prevalence of high IgG4 serum levels was 3.39% in non-IgG4-RD cases. Among them, the positive rates of serum IgG4 were 2.06% in patients with carcinoma and 6.3% in patients with other non-IgG4 autoimmune diseases.

Conclusion: Our established ELISA method is a reliable and convenient technique, which could be extensively used in the clinic to measure serum IgG4 levels. High levels of IgG4 were observed in IgG4-RD. However, this phenomenon could also be observed in other diseases, such as carcinomas and other autoimmune diseases. Thus, a diagnosis of IgG4 disease cannot only be dependent on the detection of elevated serum IgG4 levels.

No MeSH data available.


Related in: MedlinePlus