High Incidence of Positive Autoantibodies against Thyroid Peroxidase and Thyroglobulin in Patients with Sarcoidosis

• Published in: Clinical endocrinology (Oxford) 1997-04, Vol.46 (4), p.467-472
• Main Authors: Nakamura, Hirotoshi, Genma, Rieko, Mikami, Tomoko, Kitahara, Akira, Natsume, Hiroko, Andoh, Shinichiro, Nagasawa, Shinsuke, Nishiyama, Kozo, Chida, Kingo, Sato, Atsuhiko, Yoshimi, Teruya
• Format: Article
• Language: English
• Subjects: Age Factors; Autoantibodies - blood; Biological and medical sciences; Endocrinopathies; Female; Humans; Incidence; Iodide Peroxidase - immunology; Male; Medical sciences; Middle Aged; Non tumoral diseases. Target tissue resistance. Benign neoplasms; Prevalence; Sarcoidosis - complications; Sarcoidosis - immunology; Sex Factors; Thyroglobulin - immunology; Thyroid. Thyroid axis (diseases); Thyroiditis, Autoimmune - complications
• ISSN: 0300-0664; 1365-2265
• DOI: 10.1046/j.1365-2265.1997.1630976.x

OBJECTIVE Although abnormalities of the humoral immune system, such as increased immunoglobulin production, are known in sarcoidosis, the relationship between sarcoidosis and autoimmune disorders is uncertain. We studied the incidence of thyroid autoantibodies and the prevalence of Hashimoto’s thyroiditis in patients with sarcoidosis. PATIENTS AND MEASUREMENTS Sixty‐two patients with pulmonary sarcoidosis, diagnosed by a combination of clinical, radiographic and histological findings, were studied. As controls, three groups of subjects aged 40 and over without a known history of thyroid disease (60 patients with pulmonary diseases other than sarcoidosis, 88 hospital employees and 82 company workers), were also analysed. Antibodies against thyroid peroxidase (TPO‐Ab) and purified thyroglobulin (Tg‐Ab) were measured by radioimmunoassay and antibodies against microsomal antigen (MCHA) and thyroglobulin (TGHA), by haemagglutination. RESULTS Seventeen of 62 patients (27.4%) had either positive TPO‐Ab or Tg‐Ab or both. All the patients with positive thyroid autoantibodies were of middle or advanced age, and the incidence of positive TPO‐Ab/Tg‐Ab in patients with sarcoidosis aged 40 and over was 54.5% in males, 32.4% in females and 37.8% overall. The prevalence was significantly higher in males compared to age‐matched control males (0–7.7% in the controls), and in female patients was twice that found in controls (11.8–16.3%). Seven patients had Hashimoto's thyroiditis, indicating that the prevalence was 11.3%, and much higher than that previously reported. CONCLUSIONS The data show a remarkably high incidence of thyroid autoantibodies in patients of middle or advanced age with sarcoidosis, especially in males, and a higher prevalence of Hashimoto's thyroiditis than in previous reports.