Recurrent Painless Thyroiditis in Patients with History of Postpartum Thyroiditis

It is well known that the long-term prognosis of postpartum thyroiditis (PPT) is excellent except recurrent PPT in subsequent pregnancies and risk of progression to permanent hypothyroidism in some patients. However, the prospective observation of PPT patients who have neither consecutive gestation nor any evidence of hypothyroidism were limited. We describe three patients who have history of PPT and showed repeated painless thyroiditis in the span of more than ten years. The clinical courses of repeated painless thyroiditis were the transient thyrotoxicosis, self-limited, and not related to pregnancy. Based on the clinical courses of our three patients, it is recommended to remember that transient painless thyroiditis could be repeated as a possible long-term course of the patients with history of PPT.

Subacute Thyroiditis and Painless Thyroiditis: Clinical Characteristics of 221 Patients Diagnosed between 2009 and 2015

BACKGROUND AND OBJECTIVES: In the past, subacute thyroiditis causing thyrotoxicosis included both painful and painless subgroup, but it is representative for the painful subacute thyroiditis these days. So we evaluated the clinical and laboratory characteristics of subacute thyroiditis and compared with the painless (silent) thyroiditis, and identified predictive factors of permanent hypothyroidism and recurrence. MATERIALS AND METHODS: This was a retrospective case series study analyzing clinical data of 221 consecutive patients diagnosed between 2009 and 2015. Medical records were reviewed for diagnostic route, age distribution, laboratory data, clinical course and long-term follow up outcome. RESULTS: The mean age was 48 years; female v/s male ratio 3.4:1. Median disease duration was 110 days; mean peak free T4 level was 2.9 ng/dL. 56.7% of painless thyroiditis patients were diagnosed on health checkup or routine thyroid function test with symptoms not typically associated with thyrotoxicosis. Permanent hypothyroidism was not uncommon (11/221; 5.0%). Higher peak thyroid-stimulating hormone (TSH) was associated with permanent hypothyroidism in painless thyroiditis. Lower peak TSH was associated with recurrence rate in both subacute and painless thyroiditis. In painless thyroiditis, short duration of thyrotoxicosis phase was also associated with recurrence rate. CONCLUSION: Considerable numbers of painless thyroiditis without symptoms were diagnosed on health checkup. Higher peak TSH was associated with permanent hypothyroidism in painless thyroiditis. Recurrence rate was related with lower peak TSH in both groups.

Subacute Thyroiditis and Painless Thyroiditis: Clinical Characteristics of 221 Patients Diagnosed between 2009 and 2015

BACKGROUND AND OBJECTIVES: In the past, subacute thyroiditis causing thyrotoxicosis included both painful and painless subgroup, but it is representative for the painful subacute thyroiditis these days. So we evaluated the clinical and laboratory characteristics of subacute thyroiditis and compared with the painless (silent) thyroiditis, and identified predictive factors of permanent hypothyroidism and recurrence. MATERIALS AND METHODS: This was a retrospective case series study analyzing clinical data of 221 consecutive patients diagnosed between 2009 and 2015. Medical records were reviewed for diagnostic route, age distribution, laboratory data, clinical course and long-term follow up outcome. RESULTS: The mean age was 48 years; female v/s male ratio 3.4:1. Median disease duration was 110 days; mean peak free T4 level was 2.9 ng/dL. 56.7% of painless thyroiditis patients were diagnosed on health checkup or routine thyroid function test with symptoms not typically associated with thyrotoxicosis. Permanent hypothyroidism was not uncommon (11/221; 5.0%). Higher peak thyroid-stimulating hormone (TSH) was associated with permanent hypothyroidism in painless thyroiditis. Lower peak TSH was associated with recurrence rate in both subacute and painless thyroiditis. In painless thyroiditis, short duration of thyrotoxicosis phase was also associated with recurrence rate. CONCLUSION: Considerable numbers of painless thyroiditis without symptoms were diagnosed on health checkup. Higher peak TSH was associated with permanent hypothyroidism in painless thyroiditis. Recurrence rate was related with lower peak TSH in both groups.

The High Proportion of Painless Thyroiditis as a Cause of Thyrotoxicosis in Korea / 대한갑상선학회지

BACKGROUND AND OBJECTIVES: The most common cause of thyrotoxicosis is Graves' disease (GD), while painless thyroiditis (PT) comes in second. In Korea, the treatment of choice for GD is antithyroid drugs (ATDs). Since most cases of PT spontaneously improve, an accurate diagnosis is very important for the proper management of patients presenting with thyrotoxicosis. MATERIALS AND METHODS: Ninety-nine thyrotoxic patients were routinely checked with 99m Technetium (99mTc) thyroid scan except in pregnant or lactating women. We assessed the patients' clinical characteristics, serum levels of free T4 (FT4), thyroid stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb), thyrotropin-binding inhibitory immunoglobulin (TBII), and findings of 99mTc thyroid scan. RESULTS: Among the 99 thyrotoxic patients, 69 were diagnosed with GD and 30 had PT. All of the patients with GD, diagnosed by scan, improved clinically and the thyroid hormone returned to normal with ATDs. All patients with PT improved spontaneously without ATDs. TPOAb and TGAb were positive in 13 (43.3%) and 20 (66.7%) patients with PT, respectively. TPOAb and TGAb were positive in 45 (65.2%) and 44 (63.8%) patients with GD, respectively. TBII was positive in only 73.5% of GD, and was entirely negative in the PT group. Mean FT4 level in GD was higher than in PT, but some patients with PT showed the highest level of FT4. CONCLUSION: PT accounted for a very high proportion of thyrotoxicosis in this study. All parameters investigated such as age, sex, goiter size or nature, level of FT4, TPOAb or TGAb, and TBII were unable to differentiate GD from PT. Considering the increased proportion of PT in the current study, we recommend routine thyroid scan in all thyrotoxic patients except in pregnant or lactating women.

Thyroid Dysfunction Associated with Administration of the Long-Acting Gonadotropin-Releasing Hormone Agonist

Gonadotropin-releasing hormone (GnRH) agonist has been used in the treatment of a wide variety of sex-hormone-related diseases, as the administration of GnRH agonist can alter the secretion of gonadotropin and sex hormones. Recently, we found that the long-acting GnRH agonist aggravated hyperthyroidism and induced painless thyroiditis. This is the first report to demonstrate the association of thyroid dysfunction with GnRH agonist injection in Korea. Here, we report three cases and emphasize the clinical importance of this aggravating factor in autoimmune thyroid disease.

Thyrotoxic Periodic Paralysis Associated with Transient Thyrotoxicosis Due to Painless Thyroiditis

Thyrotoxic periodic paralysis (TPP) is a rare manifestation of hyperthyroidism characterized by muscle weakness and hypokalemia. All ethnicities can be affected, but TPP typically presents in men of Asian descent. The most common cause of TPP in thyrotoxicosis is Graves' disease. However, TPP can occur with any form of thyrotoxicosis. Up to our knowledge, very few cases ever reported the relationship between TPP and painless thyroiditis. We herein report a 25-yr-old Korean man who suffered from flaccid paralysis of the lower extremities and numbness of hands. The patient was subsequently diagnosed as having TPP associated with transient thyrotoxicosis due to painless thyroiditis. The paralytic attack did not recur after improving the thyroid function. Therefore, it is necessary that early diagnosis of TPP due to transient thyrotoxicosis is made to administer definite treatment and prevent recurrent paralysis.

Differential Diagnostic Value of Total T3/Free T4 Ratio in Graves' Disease and Painless Thyroiditis Presenting Thyrotoxicosis

BACKGROUND: It is important to differentiate Graves' disease from that of painless thyroiditis in patients with thyrotoxicosis. In this study, we evaluated the usefulness of total T3 to free T4 ratio in making a differential diagnosis between Graves' disease and painless thyroiditis. METHODS: We reviewed medical records of thyrotoxic patients, who had been diagnosed with Graves' disease or painless thyroiditis, from October 2009 to July 2011. We assessed clinical characteristics, serum levels of total T3, free T4, thyroid stimulating hormone, thyrotropin-binding inhibitory immunoglobulin, and findings of 99mTechnetium thyroid scan. We analyzed the total T3/free T4 ratios between Graves' disease and painless thyroiditis patients. RESULTS: A total of 76 untreated thyrotoxic patients "49 Graves' disease and 27 painless thyroiditis" were examined. The total T3, free T4 levels and the total T3/free T4 ratios were significantly higher in patients with Graves' disease than in those with painless thyroiditis (P 73, the possibility of Graves' disease was significantly higher than in painless thyroiditis (sensitivity, 75.5%; specificity, 70.3%). The sensitivity and specificity of the total T3/free T4 ratio in patients with free T4 < 3.6 ng/dL have been increased (sensitivity, 100%; specificity, 71.4%). CONCLUSION: The total T3/free T4 ratios was useful for making a differential diagnosis between Graves' disease and painless thyroiditis.

Value of serum iodine, urinary iodine and thyroid function in differentiating painless thyroiditis / 中国实用内科杂志

Objective To discuss the difference of levels of serum and urinary iodine and thyroid function in painless thyroiditis patients and other thyroiditis patients.Methods The patients who were preliminary diagnosed as having higher level of serum thyroid hormone were divided into Graves' disease group,subacute thyroiditis group and painless thyroiditis group.Then all the patients were divided into another two groups according to the level of autoantibody.The value of serumal thyroid hormone and serumal iodine and urinary iodine were measured and the relationship between the groups and the value were observed.Results There was close relationship between serum T 3,T 4,urinary iodine and the types of thyrotoxicosis.Conclusion The morbidity of painless thyroiditis is not uncommon.Clinical situation,serumal iodine,urinary iodine and serumal thyroid hormone may be useful for clinical diagnosis and differential diagnosis of painless thyroiditis.