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Objective:To investigate the value of immunoglobulin G4 (IgG4) and IgG4/ immunoglobulin G (IgG) ratio in the differential diagnosis of IgG4-related diseases (IgG4-RD) and other autoimmune diseases.Methods:A total of 35 patients with IgG4-RD and 937 patients with autoimmune diseases who received treatment in Beijing Hospital from January 2021 to July 2022, and 200 subjects who concurrently underwent health checkups in the same hospital were included in this study. The IMMAGE 800 and BN II automatic special protein analyzers were used to detect IgG and IgG4. The receiver operating characteristic (ROC) curve of IgG4 and IgG4/IgG ratio was plotted.Results:Serum IgG4 level and IgG4/IgG ratio in the IgG4-RD group were 2.83 (2.01, 5.07) g/L and 25% (18%, 43%) respectively, which were higher than 0.35 (0.16, 0.72) g/L, 3% (1%, 6%) in the autoimmune disease group and 0.27 (0.14, 0.49) g/L, 2% (1%, 4%) in the healthy control group ( U = 795.50, 82.50, 1 744.50, 205.50, all P < 0.001). Taking IgG4 ≥ 1.35 g/L as the standard, patients with IgG4 ≥ 1.35 g/L in the three groups were screened out. There was a statistically significant difference in IgG4/IgG ratio between the IgG4-RD group and the non-IgG4-RD group ( U = 453.50, P < 0.001). The ROC curve of IgG4 and IgG4/IgG ratio showed that when IgG4 was 1.47 g/L, the sensitivity was 91.7%, the specificity was 83.5%, and the area under the ROC curve was 0.96. When IgG4/IgG was 12.5%, the sensitivity was 91.4%, the specificity was 85%, and the area under the ROC curve was 0.96. Taking IgG4 ≥ 1.47 g/L and IgG4/IgG ≥ 12.5% as the diagnostic criteria of IgG4-RD, the sensitivity was 94.3%, the specificity was 85.9%, and the area under the ROC curve was 0.96, which were higher than the sensitivity (87.2%) and diagnostic specificity (82.6%) provided by IgG4 alone. Conclusion:Because non-IgG4-RD diseases can also have the phenomenon of increased IgG4, when IgG4 ≥ 1.47 g/L is taken as the diagnostic criteria, its diagnostic sensitivity and specificity are the highest. Combined detection of IgG4 and IgG4/IgG ratio can increase the diagnostic efficacy of IgG4-RD.
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Objective To investigate serum vitamin D levels in tuberculosis (TB) patients with different blood glucose status.Methods Two hundred and forty seven TB patients were recruited from tuberculosis clinics in Jilin province and 80 normal subjects who underwent health check up in Beijing Hospital served as controls.Blood samples were collected,fasting blood glucose (FBG) and serum vitamin D [25 (OH)D] levels were measured.Results FBG results showed that there were 95 patients with normal FBG,69 with pre-diabetes (pre-DM) and 83 with diabetes mellitus (DM).Vitamin D measurement showed that 25(OH) D level in TB patients with normal FBG,pre-DM and DM was 16.1 (10.7,26.2) μg/L,12.9 (9.6,20.1) μg/L and 12.4 (10.4,16.9) μg/L,respectively,(x2 =19.608,P ＜ 0.001) and were much lower than that in the normal controls (20.5 μg/L) (x2 =21.701,P ＜ 0.001).Proportion of TB patients with 25 (OH)D sever deficiency(＜ 10.0 μg/L)in patients with normal FBG,pre-DM and DM was 20.0％ (19/95),31.9％ (22/69),and 24.1％ (20/83) respectively (x2 =6.376,P ＜ 0.05);proportion of 25 (OH) D deficiency (10.0-19.9 ng/ml) in three groups was 41.1％ (39/95),40.6％ (28/69),and 57.8 ％ (48/83),respectively (x2 =15.141,P ＜ 0.05);sufficient 25 (OH) D (≥ 30.0 μg/L) was 14.7％ (14/95),7.2％ (5/69),and 1.2％ (1/83),respectively (x2 =19.118;P ＜0.05).While the proportion of TB patient with 25 (OH) D insufficiency (20.0-29.9 ng/ml) was 24.2％ (23/95),20.3％ (14/69),and 16.9％ (14/48) respectively (x2 =0.933,P =0.627).In TB patients with normal FBG,risk factors for 25 (OH) D deficiency were smoking (OR =5.619,95％ CI:1.293-24.424,P =0.021),cold season (OR =14.402,95％CI:4.070-50.965,P ＜ 0.001) and smear negative TB (OR =6.194,95 ％ CI:1.873-20.481,P =0.003).Living in rural area (OR =3.429,95％ CI:1.040-11.299,P =0.043) was the risk factor for 25 (OH) D deficiency in TB patients with pre-DM and age ≥ 60 years (OR =2.474,95％CI:1.086-5.623,P =0.031) was risk factor for 25 (OH) D deficiency in those with DM.Conclusions Vitamin D level is lower in TB patients than that in normal controls.The diabetic TB patients have the lowest 25 (OH) D level and have highest proportion of vitamin D deficiency and sever deficiency,particularly for elderly patients.
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Objective To investigate the influences of age and sex on the expression of serum antinuclear antibody (ANA) and its titer level.Methods The serum ANA in 993 people aged 60 years and over were detected and titer of positive serum were analyzed. They were divided into different groups according to age and sex. Two hundred healthy cases aged less than 60 years were collected as control group. Results The serum ANA positive rate was increased with age and it was significantly higher in people aged 60 years and over than aged less than 60 years (29. 1% vs. 14.0%, x2=5. 074, P=0. 025). The serum ANA positive rates were 24.1%, 30. 5% and 33.6% in people aged 60-69 group, aged 70-79 group and aged above 80 group. Among people aged 60 years and over, the positive rate was 35.8% in female group, which was higher than in male group (22. 4%) (x2= 21. 179, P=0. 05). The titre levels of the positive samples were increased with age. In control group, the samples with 1 : 100 titre was 57.1% among the positive samples, which was higher than in the elderly group (36. 3%). And in control group, the samples with 1 : 3200 titre was 0 among the positive samples, which was lower than in the elderly people group (7.6%). The ANA preliminary screening in people aged 60 years and over showed that the titre level was less than 1 : 320-1: 1000 in female and less than 1 : 100-1: 320 in male. Its specificity could be up to about 90%. Conclusions The serum ANA positive rate in people aged 60 years and over is affected by age and sex. The positive rate is higher in female than in male and it is increased with age. It suggests that 1 : 320 to 1 : 1000 could be taken as ANA preliminary screening critical value in female and 1 : 100 to 1 : 320 in male.