J Korean Soc Endocrinol.  1996 Mar;11(1):68-74.

Clinical Characteristics of Graves' Disease Patients with Undetectable Thyrotropin Binding Inhibitor Immunoglubulin (TB2)

• Cho BY
• Kim WB
• Lee HG
• Koh CS
• Kim SY
• Lee SI
• Chun JS
• Park KS

Abstract

Background
Graves disease is an autoimmune disease caused by TSH receptor antibodies. Thyrotropin binding inhibitor immunoglobulins(TBII) are detected in most Graves patients, but some patients have no TBII activities in their sera. It is unknown whether the clinical features of TBII-positive patients are different from those of TBII-negative patients. Methods: To evaluate the prevalence of TBII-negative Graves' patients and its clinical differences from TBII-positive patients, we examined TBII by radioreceptor assay in 686 consecutive untreated Graves patients. We found 84 TBII-negative patients(15 men and 69 women, mean age ±EM: 40.9±.4 years) and compared their clinical characteristics with 87 TBII-positive patients (22 men and 65 women, mean age±EM: 39.9±.5 years) who were selected randomly from the same patients group. Results: In this study, TBII was undetectable in 12.2% of patients with Graves' disease(84 of 686). TBII-negative group had a less weight loss than TBII-positive group. However, there was no significant differences in age, sex ratio, prevalence of ophthalmopathy, duration of illness and positive rate of family history for thyroid diseases between TBII-negative and -positive groups. Serum total T or T levels were not different from each other, but T3-uptake was significantly higher in TBII-positive group than that in TBII-negative group, suggesting that the free hormone levels in TBII-negative group might be lower. The thyroid uptake of 99mTcO4 was significantly higher in TBII positive group than that in TBII-negative group. Thyroid autoantibodies, including antimicrosomal and antithyroglobulin antibodies were detected in almost all patients but there were no differences in titers and positive rate between TBII-negative and -positive groups. Conclusion: Although TBII-negative Graves patients showed less weight loss and low 99mTc04 thyroidal uptake compare to TBII-positive patients, the clinical and immunological characteristics of TBII-negative patients are not different from TBII-positive one.

MeSH Terms

Antibodies
Autoantibodies
Autoimmune Diseases
Female
Graves Disease*
Humans
Male
Prevalence
Radioligand Assay
Receptors, Thyrotropin
Sex Ratio
Sodium Pertechnetate Tc 99m
Thyroid Diseases
Thyroid Gland
Thyrotropin*
Weight Loss
Antibodies
Autoantibodies
Receptors, Thyrotropin
Sodium Pertechnetate Tc 99m
Thyrotropin