Summary

Single-minded homolog 1 (SIM1) is a transcription factor that plays a role in the development of both the hypothalamus and pituitary. SIM1 gene mutations are known to cause obesity in humans, and chromosomal deletions encompassing SIM1 and other genes necessary for pituitary development can cause a Prader–Willi-like syndrome with obesity and hypopituitarism. There have been no reported cases of hypopituitarism linked to a single SIM1 mutation. A 21-month-old male presented to endocrinology clinic with excessive weight gain and severe obesity. History was also notable for excessive drinking and urination. Endocrine workup revealed central hypothyroidism, partial diabetes insipidus, and central adrenal insufficiency. Genetic evaluation revealed a novel mutation in the SIM1 gene. No other genetic abnormalities to account for his obesity and hypopituitarism were identified. While we cannot definitively state this mutation is pathogenic, it is notable that SIM1 plays a role in the development of all three of the patient’s affected hormone axes. He is now 6 years old and remains on treatment for his pituitary hormone deficiencies and continues to exhibit excessive weight gain despite lifestyle interventions.

Learning points:

• Mutations in SIM1 are a well-recognized cause of monogenic human obesity, and there have been case reports of Prader–Willi-like syndrome and hypopituitarism in patients with chromosomal deletions that contain the SIM1 gene.

• SIM1 is expressed during the development of the hypothalamus, specifically in neuroendocrine lineages that give rise to the hormones oxytocin, arginine vasopressin, thyrotropin-releasing hormone, corticotropin-releasing hormone, and somatostatin.

• Pituitary testing should be considered in patients with severe obesity and a known genetic abnormality affecting the SIM1 gene, particularly in the pediatric population.

Summary

Thyroid storm (TS) is a life-threatening condition that may suffer thyrotoxic patients. Therapeutic plasma exchange (TPE) is a rescue approach for TS with acute hepatic failure, but it should be initiated with careful considerations. We present a 55-year-old male patient with untreated Graves’ disease who developed TS. Severe hyperthyroidism and refractory atrial fibrillation with congestive heart failure aggregated to multiple organ failure. The patient was recovered by intensive multimodal therapy, but we had difficulty in introducing TPE treatment considering the risk of exacerbation of congestive heart failure due to plasma volume overload. In addition, serum total bilirubin level was not elevated in the early phase to the level of indication for TPE. The clinical course of this patient instructed delayed elevation of bilirubin until the level of indication for TPE in some patients and also demonstrated the risk of exacerbation of congestive heart failure by TPE.

Learning points:

• Our patient with thyroid storm could be diagnosed and treated promptly using Japan Thyroid Association guidelines for thyroid storm.

• Delayed elevation of serum bilirubin levels could make the decision of introducing therapeutic plasma exchange difficult in cases of thyroid storm with acute hepatic failure.

• The risk of worsening congestive heart failure should be considered carefully when performing therapeutic plasma exchange.

Summary

Severe hyponatremia and osmotic demyelination syndrome (ODS) are opposite ends of a spectrum of emergency disorders related to sodium concentrations. Management of severe hyponatremia is challenging because of the difficulty in balancing the risk of overcorrection leading to ODS as well as under-correction causing cerebral oedema, particularly in a patient with chronic hypocortisolism and hypothyroidism. We report a case of a patient with Noonan syndrome and untreated anterior hypopituitarism who presented with symptomatic hyponatremia and developed transient ODS.

Learning points:

• Patients with severe anterior hypopituitarism with severe hyponatremia are susceptible to the rapid rise of sodium level with a small amount of fluid and hydrocortisone.

• These patients with chronic anterior hypopituitarism are at high risk of developing ODS and therefore, care should be taken to avoid a rise of more than 4–6 mmol/L per day.

• Early recognition and rescue desmopressin and i.v. dextrose 5% fluids to reduce serum sodium concentration may be helpful in treating acute ODS.

Summary

A 54-year-old woman was referred to our hospital with a cervical tumor. CT revealed a cervical tumor extending to the upper mediastinum, tracheal deviation and tumor infiltration in the cervical vessels. She was followed-up because no diagnosis of malignancy was made by cytology. However, 2 months later, a CT scan showed enlargement of the tumor and tracheal stenosis, and a surgical biopsy was performed and she was diagnosed with anaplastic thyroid cancer (ATC). The tracheal tube with tracheal stenosis could not be removed due to the rapid growth of the tumor, necessitating management by mechanical ventilation. Due to the difficulty of surgical resection, she was treated with lenvatinib. A lenvatinib solution was made and administered via a nasogastric tube. After lenvatinib treatment, the tumor volume decreased and the tracheal stenosis improved. The tracheal tube was removed and oral intake became possible. She was discharged and received ambulatory lenvatinib therapy. The tumor was significantly reduced in size, but gradually grew and was exposed through the cervical wound 6 months later. Esophageal perforation occurred 10 months after the start of treatment. Lenvatinib was re-administered via a nasogastric tube. Eleven months later, the patient died of massive bleeding from the exposed cervical tumor. Patients with advanced ATC may require management with mechanical ventilation for airway stenosis or with a nasogastric tube for esophageal stenosis and perforation. We experienced a case in which lenvatinib was safely administered via a nasogastric tube while performing mechanical ventilation.

Learning points:

• An anaplastic thyroid cancer patient under mechanical ventilator management was treated with lenvatinib via a nasogastric tube.

• The lenvatinib solution can easily be prepared and administered via a nasogastric tube.

• The lenvatinib solution was effective for a patient with difficulty in oral intake.

• Lenvatinib could also improve the prognosis of an anaplastic thyroid cancer patient with severe airway and esophageal trouble.

Summary

Isolated, adult-onset central hypothyroidism is very rare, and its diagnosis can be challenging. A 42-year-old patient was referred for evaluation of a 2.8 cm thyroid nodule. She referred symptoms that could be attributed to hypothyroidism and thyroid tests showed low TSH and normal-low levels of free T4. However, evaluation of the remaining pituitary hormones and pituitary MRI were normal, yet a radionuclide scanning revealed that the thyroid nodule was ‘hot’ and the tracer uptake in the remaining thyroid tissue was suppressed. Interpretation of these studies led to a misdiagnosis of subclinical hyperthyroidism and the patient was treated with radioiodine. Soon after treatment, she developed a frank hypothyroidism without appropriate elevation of TSH and the diagnosis of central hypothyroidism was made a posteriori. Long term follow-up revealed a progressive pituitary failure, with subsequent deficiency of ACTH and GH. This case should alert to the possibility of overlooking central hypothyroidism in patients simultaneously bearing primary thyroid diseases able to cause subclinical hyperthyroidism.

Learning points:

• Although rarely, acquired central hypothyroidism can occur in the absence of other pituitary hormone deficiencies.

• In these cases, diagnosis is challenging, as symptoms are unspecific and usually mild, and laboratory findings are variable, including low, normal or even slightly elevated TSH levels, along with low or low-normal concentrations of free T4.

• In cases with low TSH levels, the coexistence of otherwise common disorders able to cause primary thyroid hyperfunction, such as autonomous nodular disease, may lead to a misdiagnosis of subclinical hyperthyroidism.

Summary

Dupilumab an inhibitor of the interleukin (IL)-4R-alpha subunit is used for the treatment of allergic diseases. The patient was a 49-year-old man who received dupilumab for the treatment of severe atopic dermatitis. He presented hyperthyroidism with elevated thyroglobulin and anti-thyroid antibody negativity at 4 months after the initiation of therapy. On scintigraphy, the thyroid radioiodine uptake was low. Ultrasonography showed a diffuse hypoechoic area in the thyroid gland. A pathological study revealed lymphocytic infiltration. The administration of dupilumab was continued because of his atopic dermatitis that showed an excellent response. The patient`s hyperthyroidism changed to hypothyroidism 3 weeks later. Six months later his thyroid function normalized without any treatment. We herein describe the case of a patient with atopic dermatitis who developed painless thyroiditis under treatment with dupilumab. To the best of our knowledge, this is the first report of this event in the literature.

Learning points:

• Dupilumab, a fully human monoclonal antibody that blocks interleukin-4 and interleukin-13, has been shown to be effective in the treatment atopic dermatitis and asthma with eosinophilia.

• Painless thyroiditis is characterized by transient hyperthyroidism and hypothyroidism and recovery without anti-thyroid treatment.

• This is the first report of painless thyroiditis as an adverse effect of dupilumab, although conjunctivitis and nasopharyngitis are the main adverse effects of dupilumab.

Summary

In this case report, we describe a 37-year-old male who presented with fever and tender neck mass. Neck ultrasonography revealed a mixed echogenic multiloculated solid-cystic lesion containing turbid fluid and occupying the right thyroid region. Thyroid function tests showed subclinical hyperthyroidism. The patient was initially diagnosed with thyroid abscess and he was subsequently treated with percutaneous aspiration and i.v. antibiotics; however, his clinical symptoms did not improve. Surgical treatment was then performed and a pathological examination revealed a ruptured epidermoid cyst with abscess formation. No thyroid tissue was identified in the specimen. The patient was discharged uneventfully. However, at the 3-month and 1-year follow-ups, the patient was discovered to have developed subclinical hypothyroidism. Neck ultrasonography revealed a normal thyroid gland. This report demonstrates a rare case of epidermoid cyst abscess in the cervical region, of which initial imaging and abnormal thyroid function tests led to the erroneous diagnosis of thyroid abscess.

Learning points:

• Epidermoid cyst abscess at the cervical region can mimic thyroid abscess.

• Neck ultrasonography cannot distinguish thyroid abscess from epidermoid cyst abscess.

• Thyroid function may be altered due to the adjacent soft tissue inflammation.

Summary

Gonadotropin-releasing hormone (GnRH) agonists, currently used in the treatment of advanced prostate cancer, have been described as a rare cause of pituitary apoplexy, a potentially life-threatening clinical condition. We report the case of a 69-year-old man with a known pituitary macroadenoma who was diagnosed with prostate cancer and started treatment with GnRH agonist leuprorelin (other hormones were not tested before treatment). Few minutes after drug administration, the patient presented with acute-onset severe headache, followed by left eye ptosis, diplopia and vomiting. Pituitary MRI revealed tumor enlargement and T1-hyperintense signal, compatible with recent bleeding sellar content. Laboratory endocrine workup was significant for low total testosterone. The patient was managed conservatively with high-dose steroids, and symptoms significantly improved. This case describes a rare phenomenon, pituitary apoplexy induced by GnRH agonist. We review the literature regarding this condition: the pathophysiological mechanism involved is not clearly established and several hypotheses have been proposed. Although uncommon, healthcare professionals and patients should be aware of this complication and recognize the signs, preventing a delay in diagnosis and treatment.

Learning points:

• Pituitary apoplexy (PA) is a potentially life-threatening complication that can be caused by gonadotropin-releasing hormone agonist (GnRHa) administration for the treatment of advanced prostate cancer.

• This complication is rare but should be taken into account when using GnRHa, particularly in the setting of a known pre-existing pituitary adenoma.

• PA presents with classic clinical signs and symptoms that should be promptly recognized.

• Patients should be instructed to seek medical care if suspicious symptoms occur.

• Healthcare professionals should be aware of this complication, enabling its early recognition, adequate treatment and favorable outcome.

Summary

Lingual thyroid (LT) gland is the most common type of ectopic thyroid tissue, but it is an extremely rare presentation. We present a case of a 41-year-old Hispanic female patient complaining of dysphonia and dysphagia. As part of the evaluation, fiber optic flexible indirect laryngoscopy (FIL) was performed which revealed a mass at the base of the tongue. The morphological examination was highly suspicious for ectopic thyroid tissue and the diagnosis was confirmed with neck ultrasound and thyroid scintigraphy. Although the patient presented subclinical hypothyroidism, levothyroxine therapy was initiated with a favorable response which included resolution of symptoms and mass size reduction. Our case portrays how thyroid hormone replacement therapy (THRT) may lead to a reduction in the size of the ectopic tissue and improvement of symptoms, thus avoiding the need for surgical intervention which could result in profound hypothyroidism severely affecting the patients’ quality of life.

Learning points:

• Benign LT and malignant LT are indistinguishable clinically and radiographically for which histopathology is recommended.

• THRT, radioactive iodine 131 (RAI) therapy, and surgical excision are potential management options for LT.

• THRT may lead to size reduction of the ectopic tissue and resolution of symptoms avoiding surgical intervention.

Summary

Pituitary infections, particularly with fungus, are rare disorders that usually occur in immunocompromised patients. Cushing’s syndrome predisposes patients to infectious diseases due to their immunosuppression status. We report the case of a 55-year-old woman, working as a poultry farmer, who developed intense headache, palpebral ptosis, anisocoria, prostration and psychomotor agitation 9 months after initial diabetes mellitus diagnosis. Cranioencephalic CT scan showed a pituitary lesion with bleeding, suggesting pituitary apoplexy. Patient underwent transsphenoidal surgery and the neuropathologic study indicated a corticotroph adenoma with apoplexy and fungal infection. Patient had no preoperative Cushing’s syndrome diagnosis. She was evaluated by a multidisciplinary team who decided not to administer anti-fungal treatment. The reported case shows a rare association between a corticotroph adenoma and a pituitary fungal infection. The possible contributing factors were hypercortisolism, uncontrolled diabetes and professional activity. Transsphenoidal surgery is advocated in these infections; however, anti-fungal therapy is still controversial.

Learning points:

• Pituitary infections are rare disorders caused by bacterial, viral, fungal and parasitic infections.

• Pituitary fungal infections usually occur in immunocompromised patients.

• Cushing’s syndrome, as immunosuppression factor, predisposes patients to infectious diseases, including fungal infections.

• Diagnosis of pituitary fungal infection is often achieved during histopathological investigation.

• Treatment with systemic anti-fungal drugs is controversial.

• Endocrine evaluation is recommended at the time of initial presentation of pituitary manifestations.