Primary hypothyroidism severely impacts the quality of life of patients through a decrease in the production of the thyroid hormones T3 and T4, leading to symptoms affecting cardiovascular, neurological, cognitive, and metabolic function. The incidence rate of primary hypothyroidism is expected to increase in the near future, partially due to increasing survival of patients that have undergone radiotherapy for head and neck cancer, which induces this disease in over half of those treated. The current standard of care encompasses thyroid hormone replacement therapy, traditionally in the form of synthetic T4. However, there is mounting evidence that this is unable to restore thyroid hormone signaling in all tissues due to often persistent symptoms. Additional complications are also present in the form of dosage difficulties, extensive drug interactions and poor patience compliance. The alternative therapeutic approach employed in the past is combination therapy, which consists of administration of both T3 and T4, either synthetic or in the form of desiccated thyroid extract. Here, issues are present regarding the lack of regulation concerning formulation and lack of data regarding safety and efficacy of these treatment methods. Tissue engineering and regenerative medicine have been applied in conjunction with each other to restore function of various tissues. Recently, these techniques have been adapted for thyroid tissue, primarily through the fabrication of regenerative scaffolds. Those currently under investigation are composed of either biopolymers or native decellularized extracellular matrix (dECM) in conjunction with either primary thyrocytes or stem cells which have undergone directed thyroid differentiation. Multiple of these scaffolds have successfully restored an athyroid phenotype in vivo. However, further work is needed until clinical translation can be achieved. This is proposed in the form of exploration and combination of materials used to fabricate these scaffolds, the addition of peptides which can aid restoration of tissue homeostasis and additional in vivo experimentation providing data on safety and efficacy of these implants.

Thyroglobulin (Tg) monitoring is the biochemical standard for surveillance of recurrent differentiated thyroid cancer (DTC). Several assays are available to quantify Tg levels: immunometric assay (IMA), radioimmunoassay (RIA), and the newer liquid chromatography tandem mass spectrometry (LC-MS). It is well known that a number of entities can interfere with the accuracy of testing, and at this point in time, no one assay perfectly balances high sensitivity with low risk of interference. In this case study, we present two cases in which treatment with desiccated thyroid extract (Armour thyroid) led to a sudden elevation in Tg, which resolved when Armour thyroid was discontinued. This elevation occurred when Tg was measured with both IMA and LC-MS, which suggests direct interference from porcine Tg rather than heterophilic or thyroglobulin antibody (TgAb) interference. We suggest that patients with a history of DTC not be treated with desiccated thyroid extracts consistent with guidelines. Furthermore, more advances need to be made in the area of Tg testing to improve specificity and avoid detection of nonhuman Tg and other similar proteins.

Thyroid is an animal-derived mixture of levothyroxine (T4) and liothyronine (T3), which are normal components of human milk. Limited data on exogenous replacement doses of levothyroxine during breastfeeding indicate no adverse effects in infants. If thyroid is required by the mother, it is not a reason to discontinue breastfeeding. The American Thyroid Association recommends that subclinical and overt hypothyroidism should be treated with levothyroxine in lactating women seeking to breastfeed.[1] Thyroid dosage requirement may be increased in the postpartum period compared to prepregnancy requirements patients with Hashimoto's thyroiditis.[2]

Liothyronine (T3) is a normal component of human milk. If replacement doses of liothyronine are required by the mother, it is not necessarily a reason to discontinue breastfeeding. However, because no information is available on the use of exogenous liothyronine during breastfeeding, an alternate drug may be preferred. The American Thyroid Association recommends that subclinical and overt hypothyroidism should be treated with levothyroxine in lactating women seeking to breastfeed.[1] Liothyronine dosage requirement may be increased in the postpartum period compared to prepregnancy requirements patients with Hashimoto's thyroiditis.[2]

The purpose of this retrospective matched-cohort study was to evaluate the stability of thyroid stimulating hormone (TSH) in patients using synthetic compared with desiccated thyroid products. Patients using a thyroid product for the treatment of hypothyroidism were matched 1:1 on age, sex, race/ethnicity, and had a follow-up period of 3 years after the index date. The primary outcome was percent of in-range TSH values. Over 3 years, TSH values in both groups were in-range 79% of the time (P = 0.905). Our results showed no difference in longitudinal TSH stability between desiccated thyroid products and synthetic levothyroxine.

Background and objectives: It is unclear why many patients with hypothyroidism prefer the use of desiccated thyroid extract (DTE) as a thyroid hormone replacement formulation over levothyroxine (LT4) treatment, as recommended by clinical practice guidelines. We analyzed patient-reported information from patient online forums to better understand patient preferences for and attitudes toward the use of DTE to treat hypothyroidism. Materials and Methods: We conducted a mixed-methods study by evaluating the content of online posts from three popular hypothyroidism forums from patients currently taking DTE (n = 673). From these posts, we extracted descriptive information on patient demographics and clinical characteristics and qualitatively analyzed posts' content to explore patient perceptions on DTE and other therapies further. Results: Nearly half (46%) of the patients reported that a clinician initially drove their interest in trying DTE. Patients described many reasons for switching from a previous therapeutic approach to DTE, including lack of improvement in hypothyroidism-related symptoms (58%) and the development of side effects (22%). The majority of patients described DTE as moderately to majorly effective overall (81%) and more effective than the previous therapy (77%). The most frequently described benefits associated with DTE use were an improvement in symptoms (56%) and a change in overall well-being (34%). One-fifth of patients described side effects related to the use of DTE. Qualitative analysis of posts' content supported these findings and raised additional issues around the need for individualizing therapy approaches for hypothyroidism (e.g., a sense of each patient has different needs), as well as difficulties obtaining DTE (e.g., issues with pharmacy availability). Conclusions: Lack of individualized treatment and a feeling of not been listened to were recurrent themes among DTE users. A subset of patients may prefer DTE to LT4 for many reasons, including perceived better effectiveness and improved overall well-being, despite the risks associated with DTE.

Around 5-10% of hypothyroid patients continue to experience profound and sometimes disabling symptoms, including fatigue, depression and impaired cognition, in spite of being adequately replaced biochemically. The use of the combination of levothyroxine and liothyronine and natural desiccated thyroid extract is controversial for reasons of costs, a lack of evidence of additional benefit over levothyroxine alone, and potential safety concerns. Clinical guidelines caution against the use of both, and advise that only in exceptional cases may a short trial be considered. Natural desiccated thyroid extract is not licensed for use in the UK. However, key deficiencies in the existing evidence-base together with improved understanding of the pharmacology of levothyroxine resistance, indicates that now is the right time for a definitive clinical trial to address this important area of uncertainty.

Armour® Thyroid (Forest Pharmaceuticals, LLC; affiliate of Allergan, Dublin, Ireland) is a natural porcine derivative thyroid supplement that is frequently used without physician monitoring by health enthusiasts as a weight loss supplement. Although there are no publications associating Armour Thyroid and major coronary events, significant drug interactions may exist. A 32-year-old male with a history of hypothyroidism, cystic acne, and solitary congenital kidney presented to the emergency room after experiencing crushing substernal chest pain radiating to his left shoulder, accompanied by diaphoresis and shortness of breath. The patient denied any tobacco use or family history of heart disease. He was self-administering 120 mg of Armour Thyroid daily. On examination, the patient was well-developed with cystic acne and a flushed appearance. His vital signs on admission were a blood pressure of 171/106 mmHg, heart rate of 88 beats per minute (bpm), and respiratory rate of 16 breaths/min. The electrocardiogram revealed marked ST-segment elevation in the anterior chest leads. Laboratory studies revealed elevated troponins. Urine drug screen was negative. The patient underwent an emergent coronary angiogram, which confirmed an occluded left anterior descending artery. He was treated successfully by thrombectomy and stenting of his left anterior descending artery. Evaluation for other causes of thrombosis was negative: glycosylated hemoglobin (HbA1C) 5.5%, low-density lipoprotein (LDL) 127 mg/dL, high-density lipoprotein (HDL) 33 mg/dL, hypercoagulable evaluation negative, and hemoglobin (Hgb) 17.1 gm/dL. Luteinizing hormone (LH) and follicle stimulating hormone (FSH) were < 0.20 miu/mL. Thyroid profile results were thyroid-stimulating hormone (TSH) 0.20 miu/mL (low), T3 free 4.08 pg/mL (high), and T4 total 1.2 mcg/dL (low), which were consistent with exogenous thyroid hormone administration. Focused questioning triggered by his cystic acne led to the discovery that the patient was self-administering exogenous testosterone replacement therapy. The patient declined to share specifics with the healthcare team. This was confirmed by a high testosterone level of 1,311 ng/dL. Hyperthyroidism increases the risk of cardiovascular events two to three times through the propagation of a hypercoagulable, hypofibrinolytic state possibly via an increase in clotting factors, a decrease in fibrinolytic enzymes, and an increased inhibition of the protein C pathway. The effect of androgens on cardiovascular mortality is uncertain. Androgens stimulate the hemostatic system, increase adverse lipid profile, and erythropoiesis. The combined therapy likely resulted in a synergistic potentiation of hypercoagulable, hypofibrinolytic effects of both agents. Given the absence of other cardiovascular risk factors, the cause of the myocardial infarction in our patient was likely due to drug interaction between Armour Thyroid and exogenous testosterone therapy. Due to the potential drug interaction between both natural and prescribed thyroid hormone and testosterone supplements, patients should be discouraged from self-administration of thyroid or anabolic steroids. Due to the lack of standardization in the T3 content, the use of Armour Thyroid should be avoided.

Effective thyroid replacement therapy may be elusive to some patients, and compounding pharmacists have an opportunity to deliver more effective therapy. Goodman & Gilman's The Pharmacological Basis of Therapeutics 12th edition states that the body usually secretes T4:T3 in an 11:1 ratio but cautions against pursuing combined thyroid replacement due to the short halflife of T3 that necessitates multiple daily dosing; no commercial availability and lack of benefit were shown in trials. Commercial combinations of T4/T3 such as Armour Thyroid and Nature-Throid have a 4.22:1 T4:T3 ratio. Applying the same concept as bioidentical hormone replacement therapy, compounding pharmacists can deliver an 11:1 ratio using a commercial T4 product and taking into account oral bioavailability of each entity. The short half-life of T3 can be remedied by taking the patient's daily T3 dose and dividing it into two slow-release capsules to be dosed every 12 hours.

Thyroid-related hormones regulate the efficiency and expression of sarco-endoplasmic reticulum calcium ATPases in cardiac and skeletal muscle. However, little is known about the relationship between thyroid hormones and calcium (Ca2+) homeostasis in the brain. It is hypothesized that manipulating rat thyroid hormone levels would induce significant brain Ca2+ adaptations consistent with clinical findings. Adult male Sprague-Dawley rats were assigned to one of three treatment groups for 28 days: control, hypothyroid (6-n-propyl-2-thiouracil (PTU), an inhibitor of thyroxine (T4) synthesis), and hyperthyroid (T4). Throughout, rats were given weekly behavioral tests. Ca2+ accumulation decreased in the cerebellum in both hyper- and hypothyroid animals. This was specific to different ER pools of calcium with regional heterogeneity in the response to thyroid hormone manipulation. Behavioral tasks demonstrated sensitivity to thyroid manipulation, and corresponded to alterations in calcium homeostasis. Ca2+ accumulation heterogeneity in chronic hyper- and hypothyroid animals potentially explains clinical manifestations of altered thyroid status.

Two patients were diagnosed as having hyperthyroidism, and both had taken the same health food. We compared three kinds of histological methods to detect thyroid gland in this health food. The first method used cytology; the second applied the cell-block method; and the last is a modification of the cell particle (CPCB) method proposed by Ushijima. It is the third method that achieved superior results, and this enabled the morphological detection of thyroid gland. Certain kinds of health foods contain dried thyroid as a "slimming supplement", and intake of these products may damage health. Histological techniques are effective for detecting the existence of dried thyroid gland. A health food is very different from clinical specimen; therefore, we have to devise appropriate skills for examining it. Such examinations will be important in the future, because it is expected that the risks of damaging health by consuming certain kinds of health food will increase.

A 21-year-old woman was referred because of abdominal pain. On physical examination, her abdomen was distended up to the umbilical region. Ultrasound and computer tomography of the abdomen revealed bilateral multiple ovarian cysts. Laboratory studies revealed increased liver function, total cholesterol and creatine phosphokinase. Further clinical investigations determined that the patient suffered from primary hypothyroidism due to autoimmune thyroiditis. The cysts resolved spontaneously after the simple replacement of a thyroid hormone. Some reports have been published of primary hypothyroidism presenting as ovarian cysts and precocious puberty in prepubertal girls. However, the case presented herein indicates that an ovarian tumor as a result of hypothyroidism may also occur in adult females. To avoid inadvertent surgery to remove an ovarian tumor, it is essential that a patient with multiple ovarian cysts and hypothyroidism be properly managed, as the simple replacement of a thyroid hormone could resolve the ovarian cysts.

The rdw rat was initially reported as having hereditary dwarfism caused by pituitary dysfunction. Subsequent studies on the rdw rat, however, have demonstrated that the primary cause of rdw dwarfism is present in the thyroid gland but not in the pituitary gland. The primary cause of rdw rat disorders is a missense mutation of the thyroglobulin (Tg) gene by a one-point mutation. In the present study, we attempted to rescue the dwarfism of the rdw rats using a diet supplemented with thyroid powder (T-powder) and a thyroid graft (T-graft). The infants of the rdw rat were successfully raised to a mature stage body weight, accompanied by elevation of serum growth hormone (GH) and prolactin (PRL), by the T-powder. Furthermore, the T-graft successfully increased the body weight with fertility. The serum GH and PRL levels in the T-graft rdw rat significantly increased. The serum thyroid-stimulating hormone (TSH) levels in the T-graft rdw rat were significantly decreased but were significantly higher than those in the control rat. The GH and PRL mRNA expression in the rdw rat with the T-graft was virtually the same as that of the control, but the TSH beta mRNA differed from that of the control rats. Thus, the dwarfism in the rdw rat is rescued by thyroid function compensation, such as that afforded by T-powder and T-graft.

Evidence is presented that many people have hypothyroidism undetected by conventional laboratory thyroid-function tests, and cases are reported to support the empirical use of Armour thyroid. Clinical evaluation can identify individuals with sub-laboratory hypothyroidism who are likely to benefit from thyroid-replacement therapy. In a significant proportion of cases, treatment with thyroid hormone has resulted in marked improvement in chronic symptoms that had failed to respond to a wide array of conventional and alternative treatments. In some cases, treatment with desiccated thyroid has produced better clinical results than levothyroxine. Research supporting the existence of sub-laboratory hypothyroidism is reviewed, and the author's clinical approach to the diagnosis and treatment of this condition is described.

We previously reported a patient with generalized vitiligo improved by oral administration of the drug for menopausal syndrome (sex hormone-thyroid powder mixture). In this study, we reevaluated the efficiency of this drug for vitiligo, and examined its pharmacological action in melanogenesis.

A case of Plummer's disease that spontaneously progressed to hypothyroidism is presented. A 49-year-old female visited our hospital because of a 3 kg decrease in body weight during the previous month and a painless nodule in the right anterior area of her neck. A diagnosis of Plummer's disease was made based on the results of thyroid function tests, thyroid scintigrams, and an ultrasonogram, but the patient's disease followed an usual clinical course. About two months later, she gradually developed manifestations of permanent hypothyroidism, and anti-thyroid autoantibodies became positive. In spite of continuous administration of levothyroxine sodium, uptake of 99mTcO4- to the nodule was unchanged or rather increased according to the consecutive thyroid scintigraphies. These results suggested that this case represented an autonomously functioning nodule with underlying silent thyroiditis and Hashimoto's disease.

We previously reported that a sex steroid-thyroid hormone (Metharmon-F; MF, 2 tablets daily) was a potent drug for treatment of vitiligo. Using five patients with generalized vitiligo who were successfully treated with oral administration of MF, we performed an immunohistochemical analysis to elucidate its action mechanism at the cellular level. Histopathologically, the repigmented skin after the treatment showed increased numbers of melanocytes and melanin granules. Immunohistochemically, there was little significant difference between the depigmented lesions before treatment and the repigmented lesion after treatment in terms of the reactivity to adrenocorticotropic hormone (ACTH) and alpha-melanocyte-stimulating hormone (alpha-MSH) in keratinocytes. The immunoreactivity to ACTH in melanocytes both before and after the treatment was minimal, but alpha-MSH in melanocytes became much stronger after the treatment, than before the treatment. The efficacy of MF in treatment of vitiligo was proven to be due to the stimulatory effect of melanocyte proliferation and melanin production via alpha-MSH.