Background: Postpartum thyroiditis is a painless, destructive lymphocytic inflammation of the thyroid gland that occurs during the postpartum period and is associated with a high prevalence of serum thyroid autoantibodies. Clinical symptoms and laboratory fi#ndings of postpartum thyroiditis vary widely during the course of illness and the final outcome of this disease remains unpredictive in some patients. The purpose of this study is to investigate the clinical course and the predictors of the outcome of the disease. Methods: Thirty-eight patients proven to have postpartum thyroiditis at the Ewha Womans University Hospital were studied. We analyzed their clinical features, laboratory findings and duration of recovery to characterize the course of the disease. Results: Their mean age was 29.0±3.3 years and the time of diagnosis was 4.9±1.9 months after delivery. The prevailed months of delivery were November through January in this study. Twenty six patients were hypothyroid and 12 were thyrotoxic at initial thyroid function. The positive rates of antithyroglobulin and anitmicrosomal antibodies were 92%, 67% in the hypothyroid group and 75%, 67% in th thyrotoxic group respectively. TSH receptor antibodies were negative in all patients. In the hypothyroid group the titers of antimicrosomal antibodies were significantly higer than the thyrotoxic group. The titers of antimicrosomal antibodies were positively correlated with serum TSH and negatively correlated with serum T4. In all patients, the titers in thyroid function tests returned to the normal range without long-term hypothyroidism. Conclusion: The titers of antimicrosomal antibodies were significantly higher in the hypothyroid group than the thyrotoxic group. Thus the titers of antimicrosomal antibodies can help guide the physician in the care of patients with postpartum thyroiditis who will probably be hypothyroid. In this study, we were surprised that all patients became euthyroid without permanent hypothyroidism.
Antibodies ; Autoantibodies ; Clinical Study ; Diagnosis ; Female ; Humans ; Hypothyroidism ; Inflammation ; Postpartum Period ; Postpartum Thyroiditis ; Prevalence ; Receptors, Thyrotropin ; Reference Values ; Thyroid Function Tests ; Thyroid Gland ; Thyroiditis

BACKGROUND: It is known that pregnancy markedly influences the clinical course of autoimmune thyroid diseases. In the postpartum period, various kinds of autoimmune thyroid dysfunctions can be observed. Thyroid dysfunction is found in 5.5-7.1% of postpartum women in the general population. Among those who show thyroid dysfunction after delivery, some will develop Graves' disease and others will develop postpartum thyroiditis. It is also known that patients with Graves' disease may manifest thyrotoxicosis in the postpartum period because of postpartum thyroiditis or relapse of the Graves' disease itself. We evaluated the clinical features of postpartum thyrotoxicosis in Graves' disease patients to find diagnostic indices that could be used in differentiating between postpartum thyroiditis and relapse of Graves' disease. METHOD: We reviewed the cases with postpartum thyrotoxicosis in patients that had a history of Graves' disease between 1995 and 2000. The diagnosis of postpartum thyroiditis had been made by means of a 99mTc thyroid scan or by the observation of a typical triphasic thyroid function change, in cases where a 99mTc thyroid scan was not possible because of breast feeding. We measured the serum TSH, free T4, free T3, TSH binding inhibiting immunoglobulin (TBII), anti-thyroid peroxidase (TPO) antibody, and anti- thyroglobulin (Tg) antibody serially from the time of the diagnosis of Graves' disease to the time of postpartum thyroid dysfunction. RESULTS: Eleven patients, 5 patients in the postpartum thyroiditis (PPT group) and 6 patients with relapse of the Graves' disease (GD group), were identified. The mean values of TBII of two groups at the time of diagnosis of Graves' disease were 40.9+/-4.8 IU/mL (PPT group), 58.9+/-23.5 IU/mL (GD group) respectively, which were insignificant. The mean values of TBII of the two groups at early pregnancy were 3.2+/-1.9 IU/mL (PPT group), 41.6+/-22.6 IU/mL (GD group) and this difference was statistically significant (p=0.009). The mean values of TBII of the two groups at the time of postpartum thyrotoxicosis were 1.9+/-1.6 IU/mL (PPT group), 51.5+/-23.2 IU/mL (GD group) which were also statistically significant (p=0.003). The mean values of anti-TPO antibody, anti-Tg antibody, disease duration, and treatment duration between the two groups were not significantly different. The onsets of thyroid dysfunction after delivery in the two groups were 2.6+/-2.0 (PPT group), 4.0+/-3.9 (GD group) months which were statistically insignificant. CONCLUSION: These data suggest that the measurement of TBII at the time of the postpartum thyrotoxic period, could help to differentiate postpartum thyroiditis from a relapse of Graves' disease in those patients that have a history of Graves' disease especially when thyroid scan is not possible because of breast feeding.
Breast Feeding ; Diagnosis ; Graves Disease* ; Humans ; Immunoglobulins ; Peroxidase ; Postpartum Period* ; Postpartum Thyroiditis ; Pregnancy ; Receptors, Thyrotropin* ; Recurrence ; Thyroglobulin ; Thyroid Diseases ; Thyroid Gland ; Thyrotoxicosis

BACKGROUND: Pregnancy affects the course of Graves' Disease (GD), and patients who initially maintain euthyroid function into their middle trimester with minimum doses of antithyroid drugs become exacerbated after delivery. Even patients who are completely cured, requiring no treatment during pregnancy, can relapse after delivery. In this study, we examined the postpartum changes in the thyroid functions of patients with GD, and attempted to determine the factors contributing to these changes. METHODS: The study subjects were recruited from pregnant women visiting our outpatient clinic for routine prenatal evaluations. 45 women previously diagnosed with GD, who had been treated and cured with hyperthyroidism, and were no longer taking any thyroid medications, were evaluated for 1 year post delivery. RESULTS: Among 45 patients, 20 (44.4%) developed thyroid disorders following delivery. Postpartum thyroiditis (PPT) developed in 8 patients (17.8%), and GD developed in 12 (26.0%). The onset of the PPT disease 3.1 +/- 1.4 months following delivery, which was significantly earlier than the 6.7 +/- 2.7 months required for the post delivery onset of GD (p=0.003). The TBII values, measured during the thyrotoxic state in each womaen, were negative in women with PPT and positive in 71.4% of women with GD (p=0.030). The duration of treatment for hyperthyroidism prior or pregnancy, the number of recurrences, and the time interval without treatment, were not associated with the development of postpartum thyroid disorders. Whereas, the mean number of past pregnancies for women who developed PPT was 3.9 +/- 2.1, and was significantly higher than the 2.2+/- 1.7 for women developing no thyroid dysfunctions (p=0.044). In 13 women their initial onset of GD occurred within one year postpartum, 7 (53.8%) having had a recurrence, which was significantly higher than in women whose disease onset occurred unrelated to delivery (5 of 32 women: 15.6%). CONCLUSION: Women with GD developed postpartum thyroid dysfunctions in 44.4% of cases. Women whose initial disease onset occurred within one year postpartum had higher recurrences of GD, and women who developed PPT had a history of higher gravidity compared to the euthyroid women postpartum. Therefore, if women with GD develop postpartum thyroid dysfunctions, the diagnosis should be made, and a treatment modality planned, following careful considerations of the patients' past obstetric history, changes in clinical manifestations and the TBII values.
Ambulatory Care Facilities ; Antithyroid Agents ; Diagnosis ; Female ; Graves Disease ; Gravidity ; Humans ; Hyperthyroidism ; Postpartum Period* ; Postpartum Thyroiditis ; Pregnancy ; Pregnant Women ; Recurrence* ; Thyroid Gland

BACKGROUND/AIMS: Graves' disease (GD) is caused by thyroid-stimulating hormone receptor (TSHR) and thyroid-stimulating immunoglobulin (TSI). We used a recently introduced, technically enhanced TSI bioassay to assess its diagnostic value and determine the cut-off in patients in high iodine intake area. METHODS: In a cross-sectional setting, we collected serum from 67 patients with untreated GD, 130 with GD under treatment, 22 with GD in remission, 42 with Hashimoto's thyroiditis, 12 with subacute thyroiditis, 20 with postpartum thyroiditis, and 93 euthyroid controls. TSI was measured using the Thyretaintrade mark bioassay, which is based on Chinese hamster ovary cells transfected with chimeric TSHR (Mc4). TSI levels are reported as a specimen-to-reference ratio percentage (SRR%). RESULTS: The TSI levels in patients with GD (either treated or not) were significantly higher than those of the remaining patients (p < 0.05). The new bioassay showed a sensitivity of 97.0% and a specificity of 95.9% with a cut-off value of 123.0 SRR% for GD. A weak correlation was found between TSI and thyrotropin-binding inhibiting immunoglobulin (TBII) (rs = 0.259, p = 0.03), but no correlation was found between TSI and tri-iodothyronine or free thyroxine. CONCLUSIONS: The Mc4-CHO bioassay showed comparable diagnostic value for GD with the conventional TBII assay. We propose a cut-off of 123.0 SRR% in areas where iodine intake is high.
Adult ; Animals ; *Biological Assay ; Biological Markers/blood ; CHO Cells ; Case-Control Studies ; Cricetinae ; Cricetulus ; Cross-Sectional Studies ; Female ; Genes, Reporter ; Graves Disease/*diagnosis/immunology/therapy ; Hashimoto Disease/diagnosis ; Humans ; Immunoglobulins, Thyroid-Stimulating/*blood ; Luciferases/genetics/metabolism ; Male ; Middle Aged ; Postpartum Thyroiditis/diagnosis ; Predictive Value of Tests ; Protein Binding ; Radioimmunoassay ; Receptors, Thyrotropin/genetics/*metabolism ; Recombinant Fusion Proteins/metabolism ; Republic of Korea ; Sensitivity and Specificity ; Thyroiditis, Subacute/diagnosis ; Transfection