Systemic lupus erythematosus (SLE) is a multiorgan-involved autoimmune disease, and it can overlap organ-specific autoimmune diseases such as autoimmune thyroid diseases, autoimmune hepatitis and inflammatory bowel disease. There may be some association between SLE and these autoimmune diseases, such as common immunological and genetic basis, but the pathogenic mechanism is still unclear. This review focuses on current knowledge regarding the prevalence and possible pathogenesis of SLE overlapping the above three autoimmune diseases.
Autoimmune Diseases ; complications ; epidemiology ; Hepatitis, Autoimmune ; complications ; epidemiology ; Humans ; Inflammatory Bowel Diseases ; complications ; epidemiology ; Lupus Erythematosus, Systemic ; complications ; epidemiology ; Prevalence ; Research ; trends ; Thyroiditis, Autoimmune ; complications ; epidemiology

Subclinical hypothyroidism (SCH) is a common clinical condition, whereas it's natural course has not been identified distinctly. We evaluated the natural history of 169 SCH patients over 5-yr and the prognostic factors including thyroid autoantibodies and thyroid ultrasonographic (USG) findings related to develop overt hypothyroidism. After 5 yr, 47.3% of patients showed normalization of TSH, while 36.7% of patients remained persistence of high level of TSH, and overt hypothyroidism developed in 11.2% of patients. There were painless thyroiditis (2.9%) and hyperthyroidism (1.7%) during 5 yr follow-up. The thyroid nodule was seen in 48.6% of patients. Most of patients had 1 to 2 nodules whereas only 3% of patients with thyroid nodule had more than 6 nodules. Overt hypothyroidism patients had more heterogenous echogenecity in USG compared to patients with normalization or persistent SCH (76.5% vs 50.0% vs 35.0%, P = 0.048) and higher prevalence positive anti-thyroid peroxidase (anti-TPO Ab) and anti-thyroglobulin antibody (anti-Tg Ab) and titer of anti-TPO Ab than other two groups. The cut off values for prediction of overt hypothyroidism were TSH > 7.45 microIU/mL, free T4 < 1.09 ng/dL and Anti-TPO Ab > 560 IU/mL. SCH has various courses and initial TSH, free T4, presence of thyroid autoantibody, titer of thyroid autoantibody; and thyroid USG findings can serve as a prognostic factor for progression of overt hypothyroidism. These parameters suggest consideration to initiate thyroid hormone treatment in SCH.
Asymptomatic Diseases/*epidemiology ; Autoantibodies/blood/immunology ; Disease Progression ; Female ; Humans ; Hyperthyroidism/epidemiology ; Hypothyroidism/*epidemiology ; Male ; Middle Aged ; Prevalence ; Prospective Studies ; Republic of Korea/epidemiology ; Thyroglobulin/immunology ; Thyroid Function Tests ; Thyroid Gland/immunology ; Thyroid Nodule/epidemiology ; Thyroiditis/epidemiology ; Thyrotropin/*blood

Epidemiological studies have reported an increasing incidence of thyroid cancer worldwide. This phenomenon is unclear whether it is apparent increase or true increase. In Korea, the incidence rate of thyroid cancer in both men and women showed abrupt increase from 1999 through 2011. The possible reason of this increase is suggested as improved screening with sensitive diagnostic procedures. If the incidence increase is real, there are risk factors such as ionizing radiation, obesity, diabetes mellitus, genetic predisposition, hormones, iodine diet, Hashimoto's thyroiditis, and pollutants contributing to this increased incidence. Exposure to ionizing radiation is a well-known risk factor for thyroid cancer. This was verified by epidemiological studies from survivors after Hiroshima and Nagasaki and the Chernobyl accident. The studies demonstrated that the dose-response relationship seems to be linear. However, a statistically significant increase has hardly been described with exposure to low dose radiation (<100 mSv). In addition, with respect to the data on adult exposure, there was no proven radiation related increase of the thyroid cancer incidence. Therefore, a clear understanding for the pathogenesis of radiation induced thyroid cancer is essential. Like other cancers, there are several gene alterations thought to be involved in pathogenesis of sporadic thyroid cancer. Whereas, the exact pathogenesis of radiation induced thyroid cancer by genetic alteration has not been demonstrated until now. Recently, gene expression profiling by microarray analysis has been applied to investigate the possible pathogenesis.
Adult ; Diabetes Mellitus ; Diet ; Epidemiologic Studies ; Epidemiology ; Female ; Gene Expression Profiling ; Genetic Predisposition to Disease ; Humans ; Incidence ; Iodine ; Korea ; Male ; Mass Screening ; Microarray Analysis ; Obesity ; Radiation, Ionizing ; Risk Factors ; Survivors ; Thyroid Gland ; Thyroid Neoplasms* ; Thyroiditis