Free T4 Levels Research Articles

Определение тиреоидного профиля у младенцев при операциях с искусственным кровообращением и гипотермией

Thyroid hormones are of a particular interest as a support for patients who have undergone cardiac surgical interventions. According to the bibliographical findings, artificial blood circulation with CPB, hypothermia and the use of dopamine reduce the level of thyroid hormones. The purpose of this research was to determine the thyroid hormone levels in infants with “acyanotic” and “cyanotic” congenital heart defects at different stages of hospitalization, comparison of the results between groups. Materials and methods used: a single-center prospective cohort study of 54 cases of surgical treatment of children with congenital heart defects (CHDs) was conducted. Correction of congenital heart disease was carried out with CPB in accordance with the approved clinical protocols. To assess the thyroid profile, thyroid-stimulating hormone (TSH), thyroxine (free T4) and triiodothyronine (free T3) were examined. The algorithm for diagnosing hormone levels included three stages - it was measured prior to, one day after and 7 to 10 days after the surgical correction of congenital heart disease. The influence of clinical (hemodynamic) manifestations during surgical intervention on the level of thyroid hormones and TSH in the early and late postoperative period was assessed. Results: the majority of pediatric patients with “acyanotic” and “cyanotic” defects had a thyroid profile within normal limits upon admission to the hospital. In the early postoperative period, a decrease in the level of thyroid hormones and TSH was noted. By the end of hospitalization, a tendency towards independent normalization was revealed in the majority of patients. Children with free T3 level one day after the surgery below normal had longer CPB application (p=0.022), longer clamping of the aorta (p=0.019) and a higher inotropic index (p=0.005) in contrast with those who had free T3 within normal values. Conclusion: the results obtained would be of help in assessing the risk for the transient decrease in the level of thyroid hormones development among children in the first year of life who underwent CHD surgical correction with CPB as well as the need for hormone replacement therapy during the early postoperative period.

Logistic regression analysis of risk factors for anxiety and depression in patients with coronary heart disease and subclinical hypothyroidism

We sought to explore the risk factors for anxiety and depression in patients with coronary heart disease and subclinical hypothyroidism through logistic regression analysis. A retrospective analysis was conducted on 168 patients with coronary heart disease and subclinical hypothyroidism admitted to the Department of Cardiology of our hospital from February 2020 to November 2022. Patients were categorized into the control group, anxiety group, and depression group based on the Hamilton Anxiety Scale (HAMA) and Hamilton Depression Rating Scale (HAMD) scores. All participants were informed about the protocol and provided signed informed consent upon inclusion. The study examined influencing factors for anxiety and depression in patients with coronary heart disease and subclinical hypothyroidism. Collect patients’ gender, age, presence or absence of chronic diseases (including Diabetes, hypertension and hyperthyroidism), sleep quality, dietary habits, psychosocial stress, living environment, social support, education level, and blood TSH levels. The linear relationship between anxiety, depression, and each influencing factor was quantified using the Pearson correlation coefficient. Blood level of TSH and free T4 were detected by chemiluminescence immunoassay. Multiple logistic regression was applied to analyze the factors influencing anxiety and depression in these patients. Various factors were identified as significant influencers of anxiety and depression in patients with coronary heart disease and subclinical hypothyroidism. For anxiety, presence or absence of chronic diseases, sleep quality, dietary habits, psychosocial pressure, living environment, and blood TSH levels were found to be influential (P < 0.05). Similarly, for depression, presence or absence of chronic diseases, sleep quality, social support, quality of life, social support, education level, and blood TSH levels were identified as significant factors (P < 0.05). The study revealed positive correlations between presence or absence of chronic diseases, psychosocial stress, and TSH levels with anxiety symptoms in patients with coronary heart disease and subclinical hypothyroidism (P < 0.05). Conversely, sleep quality, dietary patterns, and living environment showed negative correlations with anxiety symptoms (P < 0.05).Gender and age had no correlation with anxiety levels (P > 0.05). Presence or absence of chronic diseases and TSH levels were positively correlated with depressive symptoms in patients with coronary heart diseaseand subclinical hypothyroidism (P < 0.05). On the other hand, sleep quality, social support, quality of life, and educational level were negatively correlated with anxiety symptoms (P < 0.05). Gender and age had no correlation with depression (P > 0.05). Notably, TSH levels in both the anxiety and depression groups were higher than those in the control group (P < 0.05), with no significant difference in free T4 levels among the groups (P > 0.05). The combination of chronic illness types, living habits (sleep quality, dietary habits), psychosocial pressure, living environment, and TSH levels emerged as risk factors for anxiety in patients with coronary heart disease and subclinical hypothyroidism (P < 0.05). Similarly, the combination of chronic illness types, sleep quality, social support, quality of life, education level, and TSH levels were identified as risk factors for depression in these patients (P < 0.05). This logistic regression analysis underscores the significant impact of factors such as types of chronic illness, sleep quality, social support, living environment, education level, and TSH levels on anxiety and depression symptoms in patients with coronary heart disease and subclinical hypothyroidism. These findings highlight the importance of considering these multiple risk factors collectively when devising treatment and management strategies to reduce the risk of mental health issues in this patient population.

Effects on Thyroid Function of Topical Liposomal Hydrogel with 3% Povidone-Iodine Dressing

Background: Povidone-iodine (PVP-I) is an antiseptic that is commonly used as an alternative to alcohol in clinical settings, including for perioperative skin disinfection. However, the presence of iodine in PVP-I can result it adverse effects on thyroid function. This study explored the effect of PVP-I on thyroid function and assessed its safety profile.Methods: We assessed thyroid function in patients before and after treatment with Repigel (topical liposomal hydrogel with 3% PVP-I) between January 2017 and January 2023, for a period of at least 2 weeks. Patients were stratified by age, sex, and previous history.Results: No significant changes in thyroid function were observed in the 61 patients enrolled until 2 weeks after application of Repigel. Significant increases in T3, T4, and free T4 levels were detected 4 weeks after Repigel application. A comparison of the initial thyroid function test (TFT) and TFT 4 weeks post-application found that the mean T3 levels were 71.12 ± 17.55 ng/dL and 59.84 ± 18.60 ng/dL and mean T4 levels were 6.48 ± 1.49 µg/dL and 5.50 ± 1.36 µg/dL, respectively. The mean free T4 levels were 1.08 ± 0.39 ng/dL and 0.90 ± 0.19 ng/dL, respectively.Conclusion: Changes in thyroid function during the application of Repigel were observed. We conclude that thyroid function should be examined at regular intervals before and after topical application of Repigel. Additionally, clinicians should exercise caution when administering iodine-containing substances such as Repigel to patients with abnormal thyroid function, and schedule follow-up TFTs at 4 weeks.

A longitudinal observational study on activated partial thromboplastin time in hypothyroidism and effect of thyroxine supplementation

Background: Hypothyroidism is a common condition characterized by thyroid hormone deficiency, which, if untreated, can lead to severe health consequences and even death. Due to the wide range of clinical presentations and non-specific symptoms, hypothyroidism is primarily diagnosed biochemically. It can result from congenital thyroid abnormalities or iodine deficiency. Aims and objectives: Aim: To evaluate the correlation between hypothyroidism and Activated Partial Thromboplastin Time (aPTT) and assess the effect of thyroxine supplementation. Objective: To study the impact of levothyroxine supplementation on aPTT in hypothyroid patients. Materials and methods: This observational study was conducted at the General Medicine outpatient clinic and inpatient wards at Al-Ameen Medical College and Hospital, Vijayapura, from September 2022 to March 2024. A total of 80 hypothyroid patients of both sexes were included. TSH, Free T4, and aPTT levels were measured with appropriate aseptic precautions. Results: The majority of subjects were females (90%), with the highest proportion (31.3%) aged 26-35 years. The mean ± SD of pre-thyroxine TSH was 25.453 ± 19.9073, which significantly decreased to 4.299 ± 0.6738 post-thyroxine. aPTT values also decreased significantly post-treatment. A positive correlation was found between TSH and aPTT, while aPTT had a negative correlation with T3 and T4 levels. Conclusion: aPTT is significantly elevated in hypothyroid patients and shows a positive correlation with TSH levels. Regular monitoring of aPTT should be included in the follow-up of hypothyroid patients.

Relationship between thyroid function and lipid atherogenic profile in pediatric patients with multisystem inflammatory syndrome associated with COVID-19.

Concurrent alterations in the metabolic profile and thyroid dysfunction, including non-thyroidal illness syndrome (NTIS) has been reported in multisystem inflammatory syndrome in children (MIS-C). Considering the influence of thyroid hormones (TH) on lipid metabolism, we explored the relationship between thyroid function and the atherogenic lipid profile in children with MIS-C at admission and during a 12-month follow-up. we considered children admitted for MIS-C. Total and HDL cholesterol, triglycerides (TG), fasting plasma glucose, fasting plasma insulin as well as free T3 (FT3), free T4 (FT4), and TSH were assessed at diagnosis within 24 h of admission and during follow-up. TG/HDL ratio, no-HDL/HDL ratio and atherogenic index of plasma was also considered as atherogenic risk markers. we monitored 56 children. On admission, pathological levels of FT3, FT4, TSH, TG, TC, HDL, TG/HDL ratio, no-HDL/HDL ratio, and AIP were detected. Correlation analyses revealed associations between FT3, FT4, and lipid markers and TSH with TG. During monitoring, while complete restoration of TH balance was achieved at 12 months, some patients still exhibited an altered lipid profile, without correlation between thyroid function and lipid markers. we supported a relationship between thyroid function and an atherogenic lipid profile in children with MIS-C. This may result from interactions between adaptive and innate metabolic responses and genetic predisposition. Elucidating the relationship between TH and metabolic pathways during infections could help identify new biomarkers to prevent acute and fatal outcomes, improving patient prognosis and protecting long-term health.

Thyrotoxic periodic paralysis - a retrospective study from Southern India.

Thyrotoxic periodic paralysis is a rare manifestation of thyrotoxicosis. Here, we describe the clinical and biochemical features and treatment outcomes of this disorder. This retrospective study was conducted at a tertiary care centre in southern India. The clinical and biochemical features, treatment received, and therapeutic outcomes of all patients with thyrotoxicosis and acute flaccid paralysis without any other identifiable causes (cases for the study) were compared with an equal number of consecutively selected patients who presented with thyrotoxicosis but without features of paralysis (controls for the study) during the same period. In total, 41 cases and controls were included in this study. The proportion of males was 92.6% and 43.9% in the cases and controls, respectively. The mean age was 32.8 (±7.6) years (cases) and 39.7 (±11.3) years (controls). In the cases, 20% of patients presented without clinical thyrotoxic features. Graves' disease was the most common aetiology of thyrotoxicosis in both groups (92.6% of cases and 87.8% of controls). The prevalence of goitre was significantly higher among controls (90.2%) than among cases (53.7%). The mean serum potassium, free T4, total T4 and total T3 levels were significantly lower in the cases than in the controls. In these cases, two patients had an additional aetiology for persistent hypokalaemia, likely Gitelman's syndrome. This is one of the largest series of thyrotoxic periodic paralysis cases in India. In subjects with thyrotoxicosis, serum potassium, free T4, total T4 and total T3 levels were significantly lower in those with periodic paralysis than in those without.

5128 Role of Plasmapharesis- A Tale of Two Thyroid Storms

Abstract Disclosure: Z. Zhang: None. S. Joseph: None. A.M. Kodali: None. D. Eagerton: None. Background: Thyroid storm is an acute life threatening endocrinological emergency. The standard treatment for a thyroid storm is antithyroid medication, iodine, beta blockers and corticosteroids. However, when patients are refractory to standard treatment, plasmapheresis may be an effective and safe intervention. Case 1: A 49-year-old male with typical symptoms of hyperthyroidism, presented with a Ventricular tachycardia arrest. After the return of spontaneous circulation, he was febrile, and developed new onset atrial fibrillation (AF) and Amiodarone drip was started. Physical exam showed a thin gentleman with an enlarged thyroid. ECHO showed LVEF 50% with moderate to severe dilatation of left atrium and mild mitral and tricuspid valve regurgitation. CT abdomen/pelvis and CTA chest did not show any pathology. Labs showed TSH of 0.02 (reference range: 0.465-4.68); Free T 4 &amp;gt;6.99 (reference range: 0.78- 2.19). He was started on Propylthiouracil (PTU), Hydrocortisone, Potassium Iodide, and Cholestyramine. His blood pressure was too low to tolerate a beta blocker. He developed increased liver enzymes thought to be due to shocked liver. PTU was switched to Methimazole due to less risk of hepatotoxicity. A Thyroid Stimulating immunoglobulin was 13.40 (reference range 0.00-0.55), confirming Graves’ disease. He developed multiorgan failure and plasmapheresis was initiated. His Free T4 level prior to his first apheresis was still &amp;gt;6.99 but improved to 6.20 after two days. After the second session, free T4 level drastically improved to 2.65. He sustained a level of 2.09 until his hospital discharge. Case 2: A 59-year-old male with untreated hyperthyroidism and AF, who presented with shortness of breath. He was tachycardic, febrile and developed AF with rapid ventricular response. A TSH and free T4 level showed &amp;lt;0.02 (reference range: 0.465-4.68); and &amp;gt;6.99 (reference range: 0.78- 2.19), respectively. Physical exam shows a cachectic man with an enlarged thyroid. ECHO showed reduced ejection fraction of 35% with biventricular failure. He was initially started on PTU, Potassium Iodide, hydrocortisone and esmolol drip and eventually Cholestyramine. Patient developed multisystem organ failure and PTU was switched to methimazole due to continued deterioration of his liver enzymes. Plasmapheresis started with a total of 3 sessions. His free T4 improved from 4.32 to 3.59 by the second session. Round three was performed when his Free T4 increased back to 4.56. Unfortunately, he had a sudden decline in mentation and CT head showed an acute/subacute left anterior parietal stroke and after family discussion, was palliatively extubated and expired. Discussion: This case series shows two cases of thyroid storm treated with plasmapheresis and had two stark contrasts. Further studies should be done to elucidate the usefulness of plasmapheresis for thyroid storm when refractory to standard of treatment. Presentation: 6/2/2024

6430 SAT-534 Evaluating the Effectiveness of Combined T4 and T3 Therapy or Desiccated Thyroid Versus T4 Monotherapy in Hypothyroidism: A Systematic Review and Meta-Analysis

Abstract Disclosure: M. Nassar: None. A. Hassan: None. M.T. Desouki: None. S. Ramadan: None. M.A. Hassan: None. A. Chaudhuri: None. Background: Many patients with hypothyroidism experience persistent symptoms despite normalized TSH levels, which highlights the need for alternative treatment strategies. This study aims to evaluate the effectiveness of combined T4 and T3 therapy or desiccated thyroid (DTE) compared to T4 monotherapy, with a focus on thyroid profile, lipid profile, and quality of life metrics, including the 36-point thyroid symptom questionnaire (TSQ-36), Beck Depression Inventory (BDI) scores, and General Health Questionnaire (GHQ)-28 scores. Methods: A systematic literature search was conducted using a Boolean strategy on the following databases: Embase, Medline/PubMed, and Web of Science. The search included results from the inception of each database until 11/23/2023. We used the following keywords: "Armour Thyroid," OR "Thyroid Extract," OR "Natural Desiccated Thyroid," OR "Nature-Throid," "Desiccated Thyroid," OR "NP Thyroid," OR "Synthroid," OR "Levothyroxine," OR "Liothyronine," "Cytomel," OR "Thyroid USP," OR "Unithroid." AND "hypothyroidism. " We only included RCTs. We excluded non-English articles. Results: Initially, 6,394 records were identified. After removing 477 duplicate records, 5,917 records underwent title and abstract screening, excluding 5,874 records. The full texts of the remaining 43 articles were examined for eligibility, excluding 27 articles. Ultimately, 16 studies met the inclusion criteria and were incorporated into our analysis. We included two studies on desiccated thyroid and 15 studies on combined therapy. In this meta-analysis, combination therapy with T4+T3 revealed a significant reduction in free T4 levels (mean difference (MD): -0.34; 95% CI: -0.47, -0.20), total T4 levels (mean difference: -2.20; 95% CI: -3.03, -1.37), and GHQ-28 scores (MD: -2.89; 95% CI: -3.16, -2.63) compared to T4 monotherapy. Total T3 levels increased significantly in combined therapy (MD: 29.82; 95% CI: 22.40, 37.25). The analyses demonstrated moderate to high heterogeneity. There was no significant difference in heart rate, SHBG, TSH, lipid profile, TSQ-36, or BDI score. DTE significantly increased serum total T3 levels (MD: 50.90; 95% CI: 42.39, 59.42) and significantly decreased serum total T4 (MD: -3.11; 95% CI: -3.64, -2.58) and free T4 levels (MD: -0.50; 95% CI: -0.57, -0.43) compared to T4 monotherapy. Moreover, DTE treatment showed a modest increase in TSH levels (MD: 0.49; 95% CI: 0.17, 0.80). The analyses indicated low heterogeneity. There was no significant difference in heart rate, SHBG, lipid profile, TSQ-36, GHQ-28, or BDI score. Conclusions: Our study revealed that combined therapy and DTE lead to higher T3 and lower T4 levels compared to T4 monotherapy in hypothyroidism. However, no significant effects on heart rate, lipid profile, or quality of life were noted. Given the heterogeneity of results, personalized treatment approaches are recommended. Presentation: 6/1/2024

6784 A Case of Euthyroid Hyperthyroxinemia due to Thyroid Binding Globulin Excess Syndrome

Abstract Disclosure: A.S. Iyer: None. Background: Congenital thyroid binding globulin (TBG) excess is a rare phenomenon associated with elevated serum total T3 and total T4 concentrations but normal serum concentrations of free thyroid hormones, with clinically euthyroid patients. While TBG excess can be caused by pregnancy, estrogen-secreting tumors, and estrogen therapy, congenital TBG excess follows an X-linked pattern, with hemizygous males most affected, and heterozygous females showing a spectrum of disease due to random inactivation of one X chromosome. Clinical Case: A 39-year-old Caucasian female presented as a referral from the Gastroenterology clinic due to concern for thyroid resistance syndrome. Symptoms included chronic constipation (improving with Miralax®), gradual weight gain of 8 pounds in one year, fatigue, and palpitations. She reported that her total thyroid hormone levels have always been elevated, with other thyroid labs remaining within normal limits, along with family history of similar labs noted in her two sons, father, and paternal grandmother. Upon initial encounter, TSH was 1.637 (0.430-3.550 uIU/mL), total T4 15.4 (4.8-11.7 ug/dL), total T3 231 (80-200 ng/dL), free T4 0.97 (0.70-1.25 ng/dL), free T3 3.2 (1.7-3.7 pg/mL), and albumin 4.2 (3.5-5.0 g/dL). The patient was not on oral contraceptive pills and she denied any pregnancies in the last three years. Thyroid ultrasound showed a normal-appearing homogeneous thyroid gland with a small cyst with colloid and no cervical lymphadenopathy. Initial differential diagnosis included TBG excess syndrome versus familial dysalbuminemic hyperthyroxinemia. Permission was obtained from the patient to access one of her son’s medical records from age 8-weeks old when he was also evaluated for abnormal thyroid labs. TSH was 2.144 (0.350-6.500 uIU/mL), total T4 28.2 (5.0-12.0 ug/dL), free T4 1.55 (0.8-1.8 ng/dL), and free T3 4.0 pg/mL (no reference available). Thyroid binding globulin was found to be elevated at 81 (12-26 mcg/mL) in her son and found to be elevated to 78.0 (13.5-30.9 mcg/mL) in this patient, confirming a diagnosis of TBG excess syndrome. Conclusions: TBG excess syndrome should be considered in the differential of patients with high total T3 and total T4 levels with normal levels of free T3, free T4, and TSH, especially in individuals who have a known family history and who have minimal or nonspecific symptoms. Definitive diagnosis will make further testing and treatment unnecessary. However, if these patients develop hypo- or hyperthyroidism, then use of TSH and free levels of T4 and T3 is necessary to direct management and avoid confusion. Reference: Pappa, T., and S. Refetoff. “Thyroid hormone transport proteins: Thyroxine-binding globulin, transthyretin, and albumin.” Reference Module in Neuroscience and Biobehavioral Psychology, 2017, https://doi.org/10.1016/b978-0-12-809324-5.03494-5. Presentation: 6/2/2024

8278 Myxedema Coma With COVID-19 Infection

Abstract Disclosure: R. Kalas: None. V. Manohar: None. N.S. Bapat: None. Y. Kim: None. Myxedema coma is a rare medical emergency that occurs in severe hypothyroidism with a mortality rate reaching 60%. The hallmarks include depressed mental status and hypothermia, but hypotension, hyponatremia, bradycardia, and hypoventilation can also occur. This complication can occur in patients with a longstanding history of severe hypothyroidism especially when precipitated by an acute event such as infection, myocardial infarction, or surgery. Prompt recognition and treatment of the condition is important to prevent fatal outcomes. We present a case of myxedema coma in the setting of COVID-19 infection and nonadherence to medication. A 91-year-old woman with history of hypothyroidism, hypertension, coronary artery disease, cardiomyopathy, and chronic obstructive pulmonary disease presented with dyspnea. Her home medications included levothyroxine 75 mcg daily, which she reported not taking for at least 3 weeks. Vital signs revealed a normal heart rate and blood pressure of 84 beats/min and 137/78 mmHg, but the patient was hypothermic to 35.7 °C. On exam, she was somnolent. Labs were notable for markedly elevated TSH level of 111 (0.380 - 4.700 uIU/mL), low free T4 level of 0.57 (0.93 - 1.70 ng/dL), random cortisol level of 25.5 (6.2-18.4 ug/dL), and positive SARS-COV-2 PCR test. Chest x-ray revealed bilateral lower lung parenchymal consolidations and arterial blood gas revealed a pH of 7.29 and pCO2 of 52.5 (35-45 mm Hg), indicating hypercapnia. She was treated for COVID pneumonia and given concern for COVID induced myxedema coma she was given IV levothyroxine 100 mcg for 2 days, after which the patient’s hypothermia and somnolence improved, with an improved repeat free T4 level 0.87 ng/dL. She was subsequently transitioned to oral levothyroxine 112 mcg daily and discharged after improvement of her COVID symptoms. Myxedema coma is a rare complication of decompensated hypothyroidism, frequently triggered by an infection. Thyroid hormone plays an important role in regulating both the innate and adaptive immune systems. As a result, individuals with hypothyroidism are at increased risk of acquiring infections, which can further lead to myxedema coma. COVID-19 infection has been associated with thyrotoxicosis, thyroiditis and hypothyroidism. Given the associated high mortality rate, regardless of the underlying precipitant, prompt diagnosis and early administration of thyroid hormone replacement therapy is crucial to improve outcomes. Presentation: 6/3/2024

6441 Hyperthyroidism in a patient with Lyme disease

Abstract Disclosure: J. Epstein: None. C. Berman: None. Background: Lyme disease is known to cause inflammation in many organs. There are few case reports in the literature that discuss the association between Lyme disease and thyroiditis. This case underscores the need to further research the association between Lyme disease and thyroid physiology. Clinical Case: A 15-year-old female with a history of polycystic kidney disease is referred to a pediatric endocrinologist for primary amenorrhea and hyperthyroidism. Initial thyroid function tests demonstrated suppressed TSH of 0.03 mIU/L with an elevated free T4 level of 4.0 ng/dL and total T3 of 437 ng/dL. The patient was asymptomatic with normal vital signs, and physical exam was normal without goiter, tremor, tongue fasciculations, or exophthalmos. Thyroid ultrasound demonstrated a mildly heterogenous appearance without nodules. Incidentally, Lyme disease was concurrently diagnosed based on a positive screen confirmed with immunoblot. There was no known tick exposure or rash, but the patient had recently spent time outdoors in upstate New York. Doxycycline was started for the treatment of Lyme disease and repeat thyroid tests one week later showed a decrease in free T4 and total T3 levels, although still elevated. Thyroid antibodies including thyroid peroxidase (TPO), thyroglobulin and thyroid-stimulating immunoglobulin (TSI) were negative. After finishing doxycycline treatment, she developed a hypothyroid state with a TSH of 6.39 mIU/L, free T4 of 0.6 ng/dL, and a normal total T3 of 148 ng/dL. Free T4 has since normalized however TSH remains elevated. The patient continues to be monitored closely without pharmacologic treatment. The evolution of this patient’s thyroid function is consistent with thyroiditis and appears similar to the course of Hashitoxicosis, however antibodies remain negative. There is literature that suggests molecular mimicry between Borrelia proteins and thyroid autoantigens due to amino acid sequence homology. Some Borrelial proteins are found to share antigenic properties with multiple thyroid related proteins, specifically the TSH receptor, TPO, thyroglobulin and sodium iodine symporter, potentially leading to thyroiditis. Three case reports describe adults with hyperthyroidism in the setting of Lyme disease, however in these cases thyroid antibodies (TPO +/- thyroglobulin) were positive. Two of these patients were asymptomatic, similar to our patient. This phenomenon has never been described in a pediatric patient and illustrates the need to consider Lyme disease as a potential cause of destructive, transient, thyroiditis. Presentation: 6/1/2024

6575 From Tonsils to the Thyroid: A Rare Case of Acute Suppurative Thyroiditis in an Immunocompetent Adult

Abstract Disclosure: F. Sajid: None. A. Mubashir: None. F. Mohsin: None. M. Sattar: None. Introduction: Acute suppurative thyroiditis (AST) is a rare infection of the thyroid gland due to its high vascularity, protective encapsulation, and high iodine content. Most AST cases occur in children with anatomical aberrations or in immunosuppressed adults. Here, we describe a case of AST in an immunocompetent woman. Case: A 54-year-old woman with no medical history presented to the emergency department due to dyspnea, dysphagia, and odynophagia for two days. She reported a four-day history of sore throat, fever, and chills. She was saturating well on room air but was sitting in a tripod position. She had erythema, swelling, tenderness to palpation in the anterior neck with a hoarse voice, and moderate trismus. Nasopharyngoscopy revealed no mass, but the scope could not pass beyond the velum due to edema. The patient’s condition quickly deteriorated, necessitating emergent intubation for acute hypoxic respiratory failure. After intubation, the patient had cardiac arrest with asystole requiring resuscitation and successful ROSC. The initial CT scan showed extensive soft tissue abnormalities in the nasopharynx and parapharyngeal tissues, extending to the thyroid gland and mediastinum with the possibility of developing abscesses. A thyroid ultrasound showed a heterogeneous thyroid gland without nodules or increased vascularity. Treatment commenced with ampicillin-sulbactam. Laboratory results showed Free T4 of 4.74 ng/dL (0.58-1.64), TSH 0.03 MCIU/mL (0.39-4.08), Total T3 1.56 ng/dL (0.72-1.35), WBC 19.3 K/UL (4.8-10.8), and elevated ESR and CRP levels. Thyroid-stimulating Immunoglobulin (TSI), Thyroid Peroxidase (TPO) Antibody, and Thyrotropin Binding Inhibitory Immunoglobulin (TBII) were negative, making AST the top differential. Methimazole was initiated due to concerns of thyroid storm, but it was quickly tapered due to a significant decrease in Free T4 levels and suspicion of AST. A repeat CT scan revealed more defined abscesses along the bilateral pharyngeal walls extending to the thyroid bed. The patient underwent bilateral tonsillectomy and drainage of the abscesses. She was extubated the following day. Cultures from the abscesses grew rare Klebsiella pneumoniae, susceptible to Ampicillin-sulbactam. A barium swallow on day 14 showed no evidence of a pyriform sinus fistula. She was discharged on day 15 with Augmentin for 7 days. On discharge, free T4 decreased to half (2.39 ng/dL), and Total T3 normalized (1.08ng/dL). Conclusion: This case presents a rare instance of AST in an immunocompetent patient without anatomical anomalies, stemming from the spread of peritonsillar and parapharyngeal abscesses into the thyroid bed. AST should be considered in cases of deep neck infections, as it is a potentially life-threatening disease. It is crucial to identify and treat AST early to prevent complications. The primary treatment involves antibiotics, incision, and drainage. Presentation: 6/1/2024

8100 Late Onset Sheehan Syndrome 23 Years After Post-Partum Hemorrhage: A Rare Case

Abstract Disclosure: I. Dosunmu: None. A. Alvi: None. S. Kaufman: None. A. Malik: None. Introduction: Sheehan syndrome is defined as ischemic necrosis of pituitary gland following massive postpartum hemorrhage. The majority of cases remain undiagnosed for many years after delivery. We present a unique case of late onset of Sheehan syndrome 23 years after the last childbirth which was complicated by hemorrhage. Although the syndrome can present with panhypopituitarism, most patients have partial hormone deficiency which leads to a delay in the diagnosis. Patients can remain asymptomatic for many years until the body is exposed to stressful situations. This is what we believe caused our patient to develop hyponatremia after staying symptom free for 23 years. Case Description: A 46-year-old female with no medical history presented with abdominal pain and dark colored urine. Her initial vital signs were normal. Labs showed sodium of 132 mmol/L, AST of 552 U/L, ALT of 518 U/L, ALP of 196 U/L, GGT of 166 U/L. CT scan of abdomen, liver ultrasound, and liver biopsy were unremarkable. AMA was positive with value of 1.98, consistent with diagnosis of primary biliary cholangitis. On day 2 her blood pressure decreased to 76/42 mmHg and her sodium decreased to 129mmol/L and on day 5 her blood pressure was 88/43mmHg and her sodium decreased to 122mmol/L. TSH was found to be 2.54 uIu/ml. Upon further evaluation by endocrinology, patient appeared to have sluggish speech and appeared edematous particularly in her face. A free T4 was found to be less than 0.07 ng/dl and cortisol 0.5 mcg/dl, and ACTH 22.4 pg/ml, FSH of 4.2 mIU/ml, LH 1.3 mIU/ml. On further questioning, patient confirmed history of complicated childbirth 23 years ago requiring multiple transfusions and a hysterectomy and she reported agalactorrhea after delivery. Brain MRI confirmed empty sella and she was diagnosed with Sheehan syndrome. She was started on levothyroxine and hydrocortisone and ursodiol for PBC. Discussion: Delayed onset Sheehan's syndrome stems from inadequate blood supply or ischemia to the pituitary gland during childbirth. Diagnosis can be challenging due to its gradual onset and vague presenting symptoms. In our patient, the possibility of Sheehan syndrome was suspected after evaluation for hyponatremia revealed central hypothyroidism and secondary adrenal insufficiency. &amp;#x2028;The immediate initiation of hydrocortisone followed by levothyroxine, resulted in the normalization of blood pressure and sodium and an increase in free T4 levels from &amp;lt;0.07 to 0.26 four days after hormone initiation. Early diagnosis and prompt treatment are crucial for the best outcomes. Our patient reported feeling much better and denied any symptoms 6 months after discharge. Conclusion: Delayed onset Sheehan's syndrome is a rare but important condition that can occur months or years after childbirth. Early diagnosis, proper medical management, and hormone replacement therapy are essential for improving the quality of life for affected women. Presentation: 6/2/2024

7314 The Thyroid Tetralogy: Hypothyroidism, Graves' Disease, AFTN, and Thyroid Cancer in a Single Patient

Abstract Disclosure: F. Sajid: None. F. Mohammadrezaei: None. K. Tiwari: None. J. Shapiro: None. F. Mohsin: None. T. Lin: None. Introduction: In this case, we explore a rare and complex situation involving a patient's shift from hypothyroidism to hyperthyroidism. This transition led to the diagnosis of Marine Lenhart Syndrome (MLS), an uncommon condition characterized by the coexistence of Graves' disease and autonomously functioning thyroid nodules (AFTNs). Adding to the complexity of the case, the patient was also diagnosed with papillary thyroid carcinoma (PTC). Case Presentation: A 47-year-old woman with a history of hypothyroidism, treated with levothyroxine for 14 years, presented with palpitations, weight loss, and insomnia for a few months. Her levothyroxine dose was gradually reduced and eventually discontinued by her primary care physician due to low TSH and high free T4 levels. Post-discontinuation, her symptoms were improving. Laboratory tests showed TSH 0.01 mIU/mL (0.39-4.08), Thyroglobulin (TG) 72 ng/mL (3-40), Free T4 2.5 ng/dL (0.8-1.8), Free T3 11.5 ng/dL (0.2-0.5ng/dL). Furthermore, Thyrotropin Receptor Antibody (TRAb), and Thyroid Peroxidase Antibody (TPO Ab) were positive leading to a diagnosis of Graves' Disease and initiation of Methimazole. After three months on Methimazole, her TSH remained suppressed with normalized free T4 and T3 levels. A thyroid ultrasound revealed bilateral nodules, with a calcified well-circumscribed nodule in the right mid-pole. A Radioactive iodine uptake (RAIU) scan showed a hyperfunctioning right mid-pole thyroid nodule. Fine-needle aspiration biopsy was consistent with Bethesda V, suggestive of possible malignancy. Consequently, she underwent a total thyroidectomy, with pathology confirming multifocal classic PTC, stage pT1bN0. Post-surgery, she developed hypothyroidism and was started on levothyroxine. Four weeks later, her TSH remain suppressed, other thyroid function tests and calcium levels were within normal range: TSH 0.01 mIU/mL, Free T4 1.0 ng/dL, TG 4.6 ng/mL, Thyroglobulin antibodies 1 IU/mL (less than or equal to 1), PTH intact 43 pg/mL (16-77), and Calcium 8.9 mg/dL (8.6-10.2). Conclusion: This case represents a complex and unusual medical scenario where a patient transitioned from hypothyroidism to hyperthyroidism, ultimately leading to the diagnosis of MLS in conjunction with PTC. The exact mechanism behind this transition is not fully understood. In the management of hypothyroidism, adjustments in thyroxine dosage are common, but significant tapering of the dose should prompt further investigation. The presence of PTC in AFTNs is considered rare, as AFTNs are typically characterized as hot nodules, implying they are hyperfunctioning and generally considered to be less likely malignant compared to cold nodules. This case underscores the need for comprehensive evaluation and follow-up in patients with thyroid disorders, especially when there is a change in thyroid function or the presence of nodules. Presentation: 6/3/2024

6418 Treatment of Subclinical Hyperthyroidism and Incident Atrial Fibrillation

Abstract Disclosure: M. Jay: None. P. Huan: None. N. Cliffe: None. J. Rakoff: None. E. Morris: None. P. Kavsak: Advisory Board Member; Self; Roche Diagnostics, QuidelOrtho, Siemens. Consulting Fee; Self; QuidelOrtho, Roche Diagnostics. Grant Recipient; Self; QuidelOrtho. Speaker; Self; Abbott Laboratories. Other; Self; Siemens(Other Research Support (includes receipt of drugs, supplies, equipment or other in-kind support), Speaker/Honoraria)). M. Luthra: Advisory Board Member; Self; Bayer, Inc., Novonordisk. Consulting Fee; Self; Bayer, Inc., Novonordisk. Speaker; Self; Lilly/BI alliance, Novonordisk, Sanofi. Z. Punthakee: None. Background: Treating overt hyperthyroidism prevents atrial fibrillation (AF). Though subclinical hyperthyroidism (SH) has been associated with AF risk, it is unknown whether treating SH prevents AF. Objective: We aimed to identify the association between treating SH and incident AF in outpatients. Methods: In a retrospective chart review, 2169 patients ≥ 18 years, diagnosed with SH between 2000-2021 were identified using the regional biochemistry database. After excluding those with prior AF, hypothyroidism, thyroid cancer, pituitary disease, and pregnancy, 360 patients categorized as treated (n=131) or untreated (n=229) were analyzed. The primary outcome was incident AF. Incidence rates were compared between the two groups over the time since SH treatment start for the treated group, and time since diagnosis of SH for the untreated group. Pharmacoepidemiologic Cox analysis adjusted for age and hypertension, with treatment as a time dependent covariate was used to account for untreated time in the treated group. Secondary outcomes were AF prevalence, P wave duration on ECG, as well as ventricular and ascending aorta diameters on echocardiogram. We included sensitivity and subgroup analyses. Results: Mean age of patients with SH was 55.19 years, 78% were female, 43% had toxic nodules and 14% had Grave’s disease. Amongst the 19 patients who developed AF, 58% had toxic nodules and no patient had Grave’s disease. In the treated and untreated groups, AF occurred in 3.1% and 6.6% (p=0.15) and AF incidence was 0.8 and 1.4 %/year (p=0.31), respectively. The hazard ratio (HR) was 0.60 (95% CI 0.19-1.92; p=0.39). In the subgroup of patients with free T4 (FT4) ≥ 15 pmol/L, AF incidence was 0.5 and 3.0 %/yr in the treated and untreated groups, respectively (p=0.01), while adjusted HR was 0.185 (95% CI 0.022-1.59, p=0.12). In those with TSH ≤ 0.1 mU/L, treatment was not associated with AF incidence. As some cases of AF were documented nearly simultaneously with treatment of SH, a sensitivity analysis was performed reassigning 2 patients diagnosed with AF &amp;lt;30 days after starting SH treatment to the untreated group. Here, in the treated and untreated groups, AF occurred in 1.6% and 7.4% (p=0.02), and AF incidence was 0.4 and 1.8 %/year (p=0.02), respectively. The HR was 0.25 (0.06-1.13; p=0.07). In the treated versus untreated groups, the mean p wave duration, ventricular diameter, and ascending aorta diameter were 73.47 vs 73.42 ms (p=0.99), 4.29 vs 4.34 cm (p=0.86), and 3.33 vs 3.23 cm (p=0.58), respectively. Conclusions: We report the first study assessing the effect of treating SH in preventing incident AF. There was an overall trend towards lower AF following treatment of SH. Lack of statistical significance may be related to small sample size, supporting the need for larger scale studies. These data suggest the etiology of SH (toxic nodules) and FT4 levels could be factored into treatment decisions. Presentation: 6/2/2024

8319 Pituitary Apoplexy Leads to the Spontaneous Resolution of Hypercortisolism Secondary to Cushing Disease: A Clinical Case

Abstract Disclosure: N. Sweis: None. J. Sanchez Perez: None. M. Fariduddin: None. R.M. Sargis: None. D.J. Toft: None. S. Reutrakul: None. Background: Pituitary apoplexy is a potentially fatal condition involving the infarction or hemorrhage of the pituitary gland. Rarely, it can occur in the setting of an ACTH-secreting pituitary adenoma. Clinical Case: A 27-year-old female with a past medical history of obesity, spontaneous miscarriages, and amenorrhea presented to the ER with an acute onset frontal headache of throbbing quality, associated with nausea and vomiting. The headache began two days prior, rapidly intensified, and did not improve with oral acetaminophen. CT of the head revealed an enlarged pituitary gland, while neurovascular imaging showed no abnormalities. Her neurologic examination was normal. She denied visual changes, photophobia, neck rigidity, fevers, chills, or recent infections. Furthermore, she endorsed a weight gain of about 40 pounds over the past year despite no change in dietary habits. This was accompanied by amenorrhea, hair thinning, itchy comedonal acne, hirsutism, and a loss of libido. Her physical examination was remarkable for the presence of cushingoid features including violaceous abdominal striae, facial acne, moon facies, a dorsal fat pad, and acanthosis nigricans around the neck and axillae. Pituitary MRI with and without contrast showed an enlarged sellar and suprasellar macroadenoma measuring approximately 2.1x1.4x1.2 cm abutting the optic chiasm. The visualized lesion contained hemorrhagic products, suggesting pituitary apoplexy. Biochemical testing on admission included a low morning plasma cortisol of 6.5 ug/dL (ref. range: 6.7-22.6 ug/dL), a 24-hour urine free cortisol of 12.0 (&amp;lt;=45.0 ug/24 hour), and an elevated ACTH of 145.0 pg/mL (7.2 - 63.3 pg/mL). A1c was 5.8% (&amp;lt;5.7%). Serum levels of prolactin, IGF1, GH, LH, FSH, TSH, Free T4, estradiol, total and bioavailable testosterone were within normal limits. She was evaluated with an ACTH stimulation test, which showed a morning cortisol level of 1.2 ug/dL at baseline, lower from prior. Cortisol levels were adequately increased at 19.6 ug/dL and 22.6 ug/dL, 30 and 60 minutes after the administration of Cosyntropin 250 mcg, respectively (&amp;gt;=18 ug/dL after 30-60 mins). The level of ACTH at the time was also decreased to 76.6 pg/mL. The patient was therefore started on steroid replacement therapy with hydrocortisone and later underwent transsphenoidal resection of the pituitary mass without complications. Histopathological examination of the resected mass showed pituitary adenoma cells with diffuse weak to moderate ACTH staining, most consistent with a sparsely granulated corticotroph pituitary adenoma. Conclusion: We report an interesting case of Cushing disease that spontaneously resolved after pituitary apoplexy. Our case underlines the importance of close monitoring of such patients who may rapidly undergo a period of adrenal insufficiency after hypercortisolism. Presentation: 6/3/2024

12475 Revisiting Myxedema Coma

Abstract Disclosure: M.H. Islam: None. D.R. Jimenez Corado: None. S. Siddiqui: None. M.F. Aquino Camey: None. S. Yeasmin: None. Background: Myxedema coma is a rare and life-threatening complication of hypothyroidism.Although it is rare in the era of better diagnostics and treatment modalities, its life-threatening nature mandates its timely recognition and better understanding. Case:81-year-old female with a history of hypothyroidism (unclear medication compliance) and alcohol use disorder was admitted due to alcohol withdrawal and treated with benzodiazepines. A few days prior to the presentation, she was found to have worsening confusion, unsteady gait, and multiple falls. On presentation, she was hemodynamically stable, tremulous, anxious, and oriented to person only. Blood work was remarkable for mild transaminitis. CT scan of the head revealed sequelae of microvascular disease. The day after admission, she was noted to be lethargic, and benzodiazepines were held. Later, she became hypothermic, hypotensive, bradycardic, and hyponatremic. Further investigation was pursued, revealing a TSH of 55 (normal 0.27 to 4.2 mlU/L), free T4 of &amp;lt;0.10 ng/dL (normal 0.8-1.7 ng/dL), free T3 of &amp;lt;1.0 pg/mL (normal 2.2-4 pg/mL), and cortisol of 10.7 ug/dL. Due to concerns of myxedema coma, she was started on stress dose steroids and IV levothyroxine. She was transferred to the ICU as her mental status continued to deteriorate; she underwent endotracheal intubation and received additional doses of IV levothyroxine and liothyronine. After a few days, her clinical condition and her cortisol, free T4, and free T3 levels improved; she was extubated and later discharged with an adjusted levothyroxine dose. Conclusion: It is of absolute importance to keep myxedema coma as a differential diagnosis when evaluating encephalopathic elderly patients, especially those with a history of thyroid disorders.There is a paucity of evidence to suggest a clear benefit of combining levothyroxine-liothyronine over levothyroxine alone. Treating initially with intravenous levothyroxine over oral is beneficial, as GI absorption and bioavailability are likely variable and unpredictable. In this case, oral liothyronine was used with IV levothyroxine to speed up clinical and biochemical recovery.Adrenal insufficiency often coexists with hypothyroidism, with considerable overlap in clinical features like hypotension, hypoglycemia, and hyponatremia. Administration of levothyroxine before steroids can lead to a rapid increase in metabolic rate and subsequent depletion of the existing reserves. Considering this, it can be said with fair confidence that patients need prior or concomitant stress doses of corticosteroids on an emergent basis. Later, biochemical testing can be done to evaluate the functioning of the hypothalamic-pituitary-adrenal axis and then adjust steroid doses accordingly. Presentation: 6/1/2024

6618 Risks for Cardiovascular Comorbidities Associated with Desiccated Thyroid Extract Administration

Abstract Disclosure: S.C. De La Torre: None. C. Godar: None. K. Flynn: None. A.A. Patel: None. D. Maxwell: None. M.K. Shakir: None. T.D. Hoang: None. Introduction: Levothyroxine (LT4), synthetic thyroid hormone (T4), is considered the standard of care for the management of hypothyroidism based on the current American Thyroid Association (ATA) guidelines. However, there is a small subset of patients demonstrating symptomatic improvement with desiccated thyroid extract (DTE), which is composed of desiccated porcine thyroid containing T4 and triiodothyronine (T3). Limited data or studies are available exploring long-term cardiovascular effects associated with DTE use. In this retrospective review, we aim to identify possible cardiovascular comorbidities associated with DTE use. Methods: The charts of 77 patients at a tertiary hospital center (64 females and 13 males) over the age of 18 who were prescribed DTE were reviewed. Data collected include duration of treatment, dose of treatment, pre-treatment and current weight, blood pressure (BP), TSH, free T4, and total T3 levels. New cardiovascular and other events following initiation of treatment (hypertension, coronary artery disease (CAD), myocardial infarction (MI), stroke, transient ischemic attack (TIA), atrial fibrillation, type 2 diabetes, fractures) were also obtained. Averages, medians, and totals of patient data were used for analysis. Results: Average patient age was 54 years, average duration of therapy was 77.5 months, and median DTE dose was 75 milligrams per day. Review of chart documentation from DTE initiation compared to current values identified a 2.5% increase in weight, 3.6% increase in systolic BP, 0.8% decrease in diastolic BP, 60.9% decrease in TSH, 5.2% decrease in free T4, and 14.4% increase in total T3. 19.5% patients (15 total, 80% of which were female) had recorded new cardiovascular events at any time following initiation of therapy. 15 patients developed HTN, 5 developed CAD, 2 developed atrial fibrillation, 5 developed type 2 diabetes, 5 new fractures, 0 MI, 0 stroke, and 0 TIA. Conclusion: These results demonstrate new cardiovascular events in our study population following the initiation of DTE, but it is unclear whether these events were directly associated with DTE use versus other factors based on our available data. Limitations of our study include small study size, uneven gender distribution, and data significance would be improved with comparison to a control group. Additional studies are needed to further evaluate long-term cardiovascular risk factors associated with DTE use. Presentation: 6/2/2024

8124 Prevalence and Characteristics of Patients with Hypothyroidism in the Danish Blood Donor Study

Abstract Disclosure: N.L. Frisk: None. J.R. Shorter: None. O.B. Pedersen: None. L.T. Dalgaard: None. Introduction: While impaired thyroid function leading to subclinical hypothyroidism and overt hypothyroidism is common in Denmark, the knowledge about the paths by which patients’ progress to impaired thyroid function is limited. Undiagnosed hypothyroidism as well as subclinical hypothyroidism constitute serious risk factors for development of cardio metabolic disease. The Danish Blood Donor Study (DBDS) is a large longitudinal cohort and biobank containing information and samples dating more than 10 years back. Blood donors donate blood every 3-6 months and each time provide a sample for research. Research question: The aim of the study was to obtain up-to-date information about prevalence and characteristics of patients with hypothyroidism in a Danish longitudinal cohort of blood donors. Methodology: The study employed a cross-sectional design. Hypothyroidism was defined based on at least two prescriptions of levothyroxine (LT4) and used for calculations of prevalence. Case numbers were compared to all controls that were currently not being prescribed LT4 nor anti-thyroid drugs (carbimazole, propylthiouracil, thiamazole). We compared cases of hypothyroidism to two different control (ctrl) groups: 1) All the participants of the DBDS having TSH levels in the normal range, and 2) Normothyroid participants matched to hypothyroid cases based on age and sex. Incidence was determined based on DBDS participants developing hypothyroidism after being enrolled into the DBDS during a 10-year follow-up. Men and women were compared separately among cases and controls. Students’ t-test was used to compare cases and controls, and corrected using Bonferroni. Major results: There were 3397 cases of hypothyroidism and 153791 ctrl subjects in the DBDS, giving a prevalence of 2.2%. 85% of cases were female, while among ctrl 50% were female. Average age of cases was 52±13 years (mean±SD) for women and 58±13 for men, while ctrls were 45±13 and 48±14 years, respectively (both P&amp;lt;0.001). BMI among cases were: 25.8±4.7 for women and 26.8±3.9 kg/m2, while cases were 25.1±4.4 and 26.0±3.6, respectively (both P&amp;lt;0.001). TSH levels were, for female cases: 4.6±4.0 iu/mL and 5.7±4.9 for men, while ctrls were 1.8±1.1 and 1.7±1.1, respectively (both P&amp;lt;0.001). Free (F) T4 levels were, for female cases: 14.4±6.4pmol/L and male: 14.0±4.6, while ctrls were: 14.8±4.5 and 15.0±3.9 respectively (P&amp;lt;0.003 for females, P&amp;lt;0.0001 for males), while FT3 levels were for cases: 4.3±1.7 and 4.3±1.4 pmol/L and 4.5±2.0 and 4.7±1.5 for ctrls (both P&amp;lt;0.0001). Conclusion: Hypothyroidism is less prevalent among blood donors than reported in the general Danish population, which is accordance with ‘the healthy donor’ bias. Hypothyroid donors were on average older and with higher BMI than normothyroid controls. Donors with hypothyroidism were generally well regulated, but despite that FT4 and FT3 levels were lower than ctrls. Presentation: 6/1/2024

7982 Is there a Connection between Alpha Thalassemia and Thyroid Disorders

Abstract Disclosure: W. Akhter: None. V. Taqi: None. J.L. Gilden: None. IntroductionA number of case reports suggest an association between thalassemia and autoimmune diseases through specific mutations and molecular pathways. An example is thyroid disease in thalassemia patients. Due to factors such as age, ethnicity and treatment protocol differences, the frequency of hypothyroidism in thalassemia patients is a wide range of 4 to 29% based on free T4 and TSH levels. Subclinical hypothyroidism is more common in thalassemia patients as compared to overt hypothyroidism. 90% of morbidity and mortality in B-Thalassemia patients is attributed to iron overload, anemia and hypoxia. Understanding this possible mechanism helps guide treatment and monitoring. Case PresentationWe present the case of a 26-year-old African American with Haitian ethnicity female, who upon routine testing was found to have a very high TSH level of 79.084 uIU/ml (nl=0.550-4.780 uIU/ml) for which 125 mcg of Levothyroxine was started, and then she was referred to the endocrine clinic. Past history was notable for sickle cell trait and alpha thalassemia trait. Patient stated that at age 12, she developed fatigue and low energy and was found to have hyperthyroidism which was treated with RAI ablation. After that, no follow up or lab tests were done until recently. The patient denied symptoms of hypo or hyperthyroidism or enlargement of the thyroid gland. She denied any family history of thyroid disorders. After presenting to the endocrine clinic a few days later, she was diagnosed with postprocedural hypothyroidism and the same dose of levothyroxine was continued. Physical exam was unremarkable and no thyromegaly was appreciated on exam. Labs were notable for decreased Hemoglobin of 11.4 g/dL (nl=12-16 g/dL) and CMP was unremarkable except low glucose of 65 mg/dL (nl=70-99 mg/dL). The patient’s most recent labs after 8 weeks of taking Levothyroxine were notable for TSH of 14.65 uIU/ml (nl=0.550-4.780 uIU/ml) and free T4 of 1 ng/dL (nl= 0.89-1.76 ng/dL) and the patient admitted to having still no thyroid symptoms and a little more energy. ConclusionEndocrinopathies are common complications of thalassemia with hypothyroidism being the second most common endocrine disorder in thalassemia patients after hypogonadism, reported in 5.6-17% of patients. In thalassemia patients, endocrine disorders have to be managed as early as possible. Therefore, it is recommended that an endocrine evaluation be carried out in thalassemia patients at a young age.Monitoring for glucose homeostasis, hypothyroidism and hypoparathyroidism is also warranted. Physicians caring for thalassemia patients should perform routine screening for and treat thyroid dysfunction appropriately. Reference: De Sanctis V, Soliman AT, Canatan, et al.. Thyroid Disorders in Homozygous β-Thalassemia: Mediterr J Hematol Infect Dis. 2019 May 1;11(1):e2019029. doi: 10.4084/MJHID.2019.029. PMID: 31205633; PMCID: PMC6548211. Presentation: 6/2/2024