Refractory Hypothyroidism: Unraveling the Complexities of Diagnosis and Management.

INTRODUCTION: Refractory hypothyroidism (RH) represents a challenge in the diagnosis and treatment within the field of thyroidology. It is defined as the inability to achieve disease control despite using levothyroxine (LT4) doses of 1.9 µg/kg/d or higher. METHODS: A comprehensive review, encompassing 103 articles, was conducted using the Scielo, Scopus, and EMBASE databases, providing an approach to evaluation and diagnosis of this condition. RESULTS: LT4 disintegrates and dissolves within an acidic gastric environment before being absorbed in the jejunum and ileum. It then extensively binds to serum transporter proteins and undergoes deiodination to yield tri-iodothyronine, the biologically active hormone. There are various nonpathological causes of RH, such as noncompliance with treatment, changes in the brand of LT4, food and drug interferences, as well as pregnancy. Pathological causes include lactose intolerance, Helicobacter pylori infection, giardiasis, among others. The diagnosis of RH involves conducting a thorough medical history and requesting relevant laboratory tests to rule out causes of treatment resistance. The LT4 absorption test allows for the identification of cases of malabsorption. The treatment of RH involves identifying and addressing the underlying causes of noncompliance or malabsorption. In cases of pseudomalabsorption, supervised and weekly administration of LT4 may be considered. DISCUSSION: Early recognition of RH and correction of its underlying cause are of utmost importance, as this avoids the use of excessive doses of LT4 and prevents cardiovascular and bone complications associated with this condition.

Environmental factors related to the origin and evolution of differentiated thyroid cancer: a narrative review.

INTRODUCTION: The global incidence of thyroid cancer (TC) has increased in the last decades. While improvements in diagnosis may contribute, overdiagnosis is also a possibility. This review focuses on the epidemiology, risk factors, and immune microenvironment associated with differentiated TC (DTC). AREAS COVERED: A search was conducted in Scielo, Scopus, and EMBASE databases, involving 72 articles. TC is the most common endocrine neoplasm, with DTC form being predominant. Its incidence has globally risen, particularly among women aged over 45. Endogenous risk factors for DTC include genetic disorders, race, age, female gender, obesity, and type 2 diabetes mellitus. Environmental risks involve ionizing radiation, whether through therapeutic treatment or environmental contamination from nuclear accidents, iodine deficiency, endocrine disruptors, residence in volcanic areas, environmental pollution, and stress. The use of anti-obesity medications remains controversial. The tumor's immune microenvironment is the histological space where tumor cells interact with host cells, crucial for understanding aggressiveness. Immunotherapy emerges as a promising intervention. EXPERT OPINION: Recent advances in DTC management offer transformative potential, requiring collaborative efforts for implementation. Emerging areas like precision medicine, molecular profiling, and immunotherapy present exciting prospects for future exploration, shaping the next era of diagnostic and therapeutic strategies in thyroid cancer research.

The global incidence of thyroid cancer (TC) has significantly increased, attributed partly to improved diagnosis and potentially to overdiagnosis. This review focuses on the epidemiology, risk factors, and immune microenvironment associated with differentiated TC (DTC). DTC is the most common endocrine neoplasm, and predominantly affects women over 45 years old. Endogenous risk factors include genetic disorders, race, age, female gender, obesity, and type 2 diabetes mellitus (T2DM). Environmental risks encompass ionizing radiation, iodine deficiency, endocrine disruptors, volcanic residence, pollution, and stress. The use of glucagon-like peptide 1 agonists remains controversial. The tumor's immune microenvironment is crucial for understanding aggressiveness, with immunotherapy showing promise. Understanding both macro and microenvironmental factors is crucial for devising effective prevention and treatment strategies for DTC.

Calcitonin-producing Duodenal Neuroendocrine Tumor: A Case Report and Literature Review.

INTRODUCTION: Neuroendocrine tumors [NETs] exhibit a wide range of clinical presentations, including the production of various hormones. Calcitonin, a sensitive marker for medullary thyroid cancer [MTC], is nonspecific and may be elevated in extra-thyroidal NETs. CASE REPORT: We present the case of a 64-year-old female patient who underwent total thyroidectomy due to a nodule in the isthmus, with a fine-needle aspiration biopsy indicating follicular neoplasia. Pathological examination revealed macro- and micro-nodular thyroid hyperplasia, along with a parathyroid adenoma. During postoperative follow-up, a progressive elevation of calcitonin was observed, reaching 64.2 pg/ml, while carcinoembryonic antigen levels remained normal. Since no MTC foci were found upon reviewing the thyroidectomy specimen, an investigation into the origin of the elevated calcitonin was initiated. Serum chromogranin A and specific neuronal enolase levels were within normal ranges. Tc-99m HYNIC-TOC scintigraphy yielded negative results. Additionally, an upper gastrointestinal endoscopy revealed a submucosal lesion in the second portion of the duodenum, with a biopsy confirming a grade 1 NET. The patient underwent Whipple surgery and hepatic metastasectomy. Postoperatively, a decrease in baseline serum calcitonin levels was observed. Seven years after surgery, she continues specialized monitoring with no biochemical or imaging evidence of disease. CONCLUSION: Serum calcitonin contributes to the diagnosis and monitoring of anterior intestine NETs.

Drug-induced hypothyroidism in tuberculosis.

INTRODUCTION: Adverse reactions to tuberculosis treatment can impact patient adherence and prognosis. Hypothyroidism is a frequent adverse reaction caused using ethionamide, prothionamide, and para-aminosalicylic acid and is often underdiagnosed. AREAS COVERED: We searched Scielo, Scopus, and EMBASE databases, including 67 articles. Antitubercular drug-induced hypothyroidism has a prevalence of 17%. It occurs after 2 to 3 months of treatment and resolves within 4 to 6 weeks after discontinuation. It is postulated to result from the inhibition of thyroperoxidase function, blocking thyroid hormone synthesis. Symptoms are nonspecific, necessitating individualized thyroid-stimulating hormone measurement for detection. Specific guidelines for management are lacking, but initiation of treatment with levothyroxine, as is customary for primary hypothyroidism, is recommended. Discontinuation of antitubercular drugs is discouraged, as it may lead to unfavorable consequences. EXPERT OPINION: Antitubercular drug-induced hypothyroidism is more common than previously thought, affecting one in six MDR-TB patients. Despite diagnostic and treatment recommendations, implementation is hindered in low-income countries due to the lack of certified laboratories. New drugs for tuberculosis treatment may affect thyroid function, requiring vigilant monitoring for complications, including hypothyroidism.

Panhypopituitarism in a Patient with Burkitt Lymphoma: A Diagnostic and Therapeutic Challenge.

Pituitary infiltration by systemic lymphoma is an exceedingly rare occurrence. Given its high mortality rate, it is crucial to recognize its clinical, biochemical and radiological features in order to provide timely intervention. We present the case of a 26-year-old male with a history of human immunodeficiency virus (HIV) infection who presented to the hospital with severe anemia, persistent fever, weight loss and diarrhea over the previous 4 months. Physical examination revealed a compromised general condition, fever, pallor, hepatomegaly and lymphadenopathy. Cervical lymph node biopsy confirmed Burkitt lymphoma (BL). During hospitalization, the patient developed polyuria, polydipsia, hypernatremia, fluid-resistant hypotension and hypoglycaemia. Corticosteroid therapy was initiated due to suspected adrenal insufficiency, resulting in clinical improvement but exacerbation of polyuria and hypernatremia. Plasma and urinary osmolarity confirmed arginine vasopressin deficiency, and assessment of anterior pituitary reserve revealed hypopituitarism, necessitating hormonal replacement therapy. Sellar magnetic resonance imaging with contrast revealed pituitary infiltration. The patient subsequently developed septic shock and died. BL accounts for approximately 10% of the cases of pituitary infiltration associated with lymphoma. Clinical presentation is heterogeneous, with panhypopituitarism often serving as the initial manifestation. Sellar magnetic resonance imaging plays a pivotal role in the differential diagnosis. Management typically entails chemotherapy, immunotherapy, radiation and hormonal replacement therapy. This case report describes a patient with BL and HIV infection who developed panhypopituitarism due to pituitary infiltration, an exceedingly rare presentation considered a medical emergency.

Methimazole-Induced Pancytopenia in a Patient with Graves' Disease: A Case Report and Literature Review.

INTRODUCTION: Methimazole is an antithyroid drug known to cause hematological toxicity, including agranulocytosis and, very rarely, pancytopenia. We herein present a case of a patient with Graves' Disease (GD) who developed methimazole-induced pancytopenia. CASE REPORT: A 53-year-old Peruvian woman with GD, initially treated with methimazole 20 mg BID, experienced odynophagia, fever, and malaise after 37 days of treatment. The initial diagnosis was agranulocytosis, leading to the discontinuation of methimazole and initiation of antibiotics. Due to persistent neutropenia, a Granulocyte Colony-stimulating Factor (G-CSF) was administered. Eight days later, she developed pancytopenia and was managed with hematopoietic agents and platelet transfusions. The patient recovered with normalization of the blood count, eliminating the need for Bone Marrow (BM) examination. Radioiodine therapy was chosen as the definitive treatment, resulting in hypothyroidism. Currently, the patient is thyroidal and hematologically stable. CONCLUSION: Methimazole-induced pancytopenia is a rare and serious complication; however, with appropriate treatment, complete recovery can be achieved.

A comprehensive review of genetic causes of obesity.

BACKGROUND: Obesity is a multifactorial chronic disease with a high, increasing worldwide prevalence. Genetic causes account for 7% of the cases in children with extreme obesity. DATA SOURCES: This narrative review was conducted by searching for papers published in the PubMed/MEDLINE, Embase and SciELO databases and included 161 articles. The search used the following search terms: "obesity", "obesity and genetics", "leptin", "Prader-Willi syndrome", and "melanocortins". The types of studies included were systematic reviews, clinical trials, prospective cohort studies, cross-sectional and prospective studies, narrative reviews, and case reports. RESULTS: The leptin-melanocortin pathway is primarily responsible for the regulation of appetite and body weight. However, several important aspects of the pathophysiology of obesity remain unknown. Genetic causes of obesity can be grouped into syndromic, monogenic, and polygenic causes and should be assessed in children with extreme obesity before the age of 5 years, hyperphagia, or a family history of extreme obesity. A microarray study, an analysis of the melanocortin type 4 receptor gene mutations and leptin levels should be performed for this purpose. There are three therapeutic levels: lifestyle modifications, pharmacological treatment, and bariatric surgery. CONCLUSIONS: Genetic study technologies are in constant development; however, we are still far from having a personalized approach to genetic causes of obesity. A significant proportion of the affected individuals are associated with genetic causes; however, there are still barriers to its approach, as it continues to be underdiagnosed. Video Abstract (MP4 1041807 KB).

Ifosfamide-induced nephrotoxicity in oncological patients.

INTRODUCTION: Ifosfamide is an alkylating chemotherapeutic agent used in the treatment of various neoplasms. Its main adverse effects include renal damage. AREAS COVERED: A comprehensive review was conducted, including 100 articles from the Scielo, Scopus, and EMBASE databases. Ifosfamide-induced nephrotoxicity is attributed to its toxic metabolites, such as acrolein and chloroacetaldehyde, which cause mitochondrial damage and oxidative stress in renal tubular cells. Literature review found a 29-year average age with no gender predominance and a mortality of 13%. Currently, no fully effective strategy exists for preventing ifosfamide-induced nephrotoxicity; however, hydration, forced diuresis, and other interventions are employed to limit renal damage. Long-term renal function monitoring is essential for patients treated with ifosfamide. EXPERT OPINION: Ifosfamide remains essential in neoplasm treatment, but nephrotoxicity, often compounded by coadministered drugs, poses diagnostic challenges. Preventive strategies are lacking, necessitating further research. Identifying timely risk factors can mitigate renal damage, and a multidisciplinary approach manages established nephrotoxicity. Emerging therapies may reduce ifosfamide induced nephrotoxicity.

Ifosfamide is a type of chemotherapy used to treat different types of cancers. However, one of its main side effects is kidney damage. Researchers reviewed 100 articles from medical databases to understand how ifosfamide affects the kidneys. The kidney damage is caused by harmful substances produced when ifosfamide is broken down in the body. These substances can harm the cells in the kidneys. Studies have shown that 13% of the patients treated with ifosfamide can die. Currently, there is no perfect way to prevent kidney damage from ifosfamide, but doctors try to protect the kidneys by giving patients plenty of fluids and using other treatments, so it's important for patients who receive ifosfamide to have their kidney function checked regularly. Although ifosfamide is effective against cancer, its potential kidney side effects should be carefully considered by doctors when deciding on the best treatment for each patient.

From liver to hormones: The endocrine consequences of cirrhosis.

Hepatocrinology explores the intricate relationship between liver function and the endocrine system. Chronic liver diseases such as liver cirrhosis can cause endocrine disorders due to toxin accumulation and protein synthesis disruption. Despite its importance, assessing endocrine issues in cirrhotic patients is frequently neglected. This article provides a comprehensive review of the epidemiology, pathophysiology, diagnosis, and treatment of endocrine disturbances in liver cirrhosis. The review was conducted using the PubMed/Medline, EMBASE, and Scielo databases, encompassing 172 articles. Liver cirrhosis is associated with endocrine disturbances, including diabetes, hypoglycemia, sarcopenia, thyroid dysfunction, hypogonadotropic hypogonadism, bone disease, adrenal insufficiency, growth hormone dysfunction, and secondary hyperaldosteronism. The optimal tools for diagnosing diabetes and detecting hypoglycemia are the oral glucose tolerance test and continuous glucose monitoring system, respectively. Sarcopenia can be assessed through imaging and functional tests, while other endocrine disorders are evaluated using hormonal assays and imaging studies. Treatment options include metformin, glucagon-like peptide-1 analogs, sodium-glucose co-transporter-2 inhibitors, and insulin, which are effective and safe for diabetes control. Established standards are followed for managing hypoglycemia, and hormone replacement therapy is often necessary for other endocrine dysfunctions. Liver transplantation can address some of these problems.

Diagnostic Role of Tomography in Addison's Disease due to Adrenal Tuberculosis: A Case Report.

INTRODUCTION: Adrenal tuberculosis remains the main cause of primary adrenal insufficiency (PAI) in tuberculosis (TB)-prevalent regions. This case report details the presentation of PAI due to adrenal TB, where the etiological diagnosis involves Abdominal Computed Tomography (CT). CASE REPORT: A 37-year-old Peruvian woman with a history of TB contact displayed symptoms of adrenal insufficiency. PAI diagnosis was established, and CT imaging unveiled bilateral adrenal enlargement with calcifications. Treatment with prednisone and anti-TB therapy led to symptomatic improvement. Unfortunately, she succumbed to pneumonia after ten months of follow-up. DISCUSSION: Adrenal TB must be considered in endemic regions and in the presence of a TB history. CT serves as a valuable diagnostic tool, particularly in settings with limited resources, revealing adrenal enlargement and calcifications. CONCLUSION: In patients with PAI, epidemiological history of TB, and when a rapid biopsy is not feasible, CT proves to be a valuable diagnostic method.

Thyroid dysfunction and female infertility. A comprehensive review.

INTRODUCTION: Female infertility is defined as the inability to achieve pregnancy following one year of consistent, unprotected sexual intercourse. Among the various endocrine factors contributing to this complex issue, thyroid dysfunction assumes a pivotal and noteworthy role. METHODS: A narrative review, encompassing 134 articles up to 2023, was conducted utilizing the PubMed/Medline, EMBASE, and Scielo databases. The primary focus of this review was to investigate the effects of thyroid dysfunction on female infertility. RESULTS: Thyroid disorders exert a significant influence on folliculogenesis, fertilization, and implantation processes. Thyroid autoimmunity, although associated with diminished ovarian reserve, does not typically necessitate levothyroxine therapy. On the other hand, both subclinical and overt hypothyroidism often require levothyroxine treatment to enhance fertility and optimize obstetric outcomes. Hyperthyroidism warrants prompt intervention due to its heightened risk of miscarriage. Furthermore, thyroid dysfunction exerts notable effects on assisted reproductive technologies, underscoring the importance of achieving euthyroidism prior to ovarian stimulation. CONCLUSION: Women presenting with thyroid dysfunction must undergo meticulous and individualized assessments since fertility outcomes, whether achieved through natural conception or assisted reproductive technologies, can be significantly influenced by thyroid-related factors.

Cushing disease in pediatrics: an update.

Cushing disease (CD) is the main cause of endogenous Cushing syndrome (CS) and is produced by an adrenocorticotropic hormone (ACTH)-producing pituitary adenoma. Its relevance in pediatrics is due to the retardation of both growth and developmental processes because of hypercortisolism. In childhood, the main features of CS are facial changes, rapid or exaggerated weight gain, hirsutism, virilization, and acne. Endogenous hypercortisolism should be established after exogenous CS has been ruled out based on 24-hour urinary free cortisol, midnight serum or salivary cortisol, and dexamethasone suppression test; after that, ACTH dependence should be established. The diagnosis should be confirmed by pathology. The goal of treatment is to normalize cortisol level and reverse the signs and symptoms. Treatment options include surgery, medication, radiotherapy, or combined therapy. CD represents a challenge for physicians owing to its multiple associated conditions involving growth and pubertal development; thus, it is important to achieve an early diagnosis and treatment in order to control hypercortisolism and improve the prognosis. Its rarity in pediatric patients has led physicians to have limited experience in its management. The objective of this narrative review is to summarize the current knowledge about the pathophysiology, diagnosis, and treatment of CD in the pediatric population.

Endocrine factors associated with infertility in women: an updated review.

INTRODUCTION: Infertility is defined as the inability to conceive after unprotected sexual intercourse for at least 12 consecutive months. Our objective is to present an updated narrative review on the endocrine causes of infertility in women. AREAS COVERED: A comprehensive review was conducted using Scielo, Scopus, and EMBASE databases, comprising 245 articles. The pathophysiology of infertility in women was described, including endocrinopathies such as hypothalamic amenorrhea, hyperprolactinemia, polycystic ovary syndrome, primary ovarian insufficiency, obesity, thyroid dysfunction, and adrenal disorders. The diagnostic approach was outlined, emphasizing the necessity of hormonal studies and ovarian response assessments. Additionally, the treatment plan was presented, commencing with non-pharmacological interventions, encompassing the adoption of a Mediterranean diet, vitamin supplementation, moderate exercise, and maintaining a healthy weight. Subsequently, pharmacological treatment was discussed, focusing on the management of associated endocrine disorders and ovulatory dysfunction. EXPERT OPINION: This comprehensive review highlights the impact of endocrine disorders on fertility in women, providing diagnostic and therapeutic algorithms. Despite remaining knowledge gaps that hinder more effective treatments, ongoing research and advancements show promise for improved fertility success rates within the next five years. Enhanced comprehension of the pathophysiology behind endocrine causes and the progress in genetic research will facilitate the delivery of personalized treatments, thus enhancing fertility rates.

Thyrotoxic Cardiomyopathy: State of the Art.

Thyroid hormones, mainly triiodothyronine, have genomic and non-genomic effects on cardiomyocytes related to the contractile function of the heart. Thyrotoxicosis, which is the set of signs and symptoms derived from the excess of circulating thyroid hormones, leads to increased cardiac output and decreased systemic vascular resistance, increasing the volume of circulating blood and causing systolic hypertension. In addition, the shortening of the refractory period of cardiomyocytes produces sinus tachycardia and atrial fibrillation. This leads to heart failure. Approximately 1% of patients with thyrotoxicosis develop thyrotoxic cardiomyopathy, a rare but potentially fatal form of dilated cardiomyopathy. Thyrotoxic cardiomyopathy represents a diagnosis of exclusion, and prompt identification is crucial as it is a reversible cause of heart failure, and heart function can be recovered after achieving a euthyroid state using antithyroid drugs. Radioactive iodine therapy and surgery are not the best initial therapeutic approach. Moreover, it is important to manage cardiovascular symptoms, for which beta blockers are the first-line therapeutic option.