This is a report on antithyroid arthritis syndrome (AAS) which is a rare adverse effect of antithyroid agents. AAS presents with severe symptoms including myalgia, arthralgia, arthritis, fever, and skin eruption due to the use of antithyroid agents. We encountered a 55-year-old woman with severe pain in the hand and forearm and arthralgia in multiple joints, including the knee, ankle, hand, and wrist on day 23 after initiation of methimazole (MMI) for Graves’ disease. Blood tests revealed elevated inflammation markers such as C-reactive protein and interleukin-6, and magnetic resonance imaging of the hands confirmed inflammation findings. After withdrawing MMI on day 25, symptoms showed a tendency toward improvement. Afterwards, inflammation markers also dropped to an almost normal range. In addition to the above findings, the absence of anti-neutrophil cytoplasmic antibodies and most vasculitis symptoms such as nephritis, skin, or pulmonary lesions led to the diagnosis of AAS. A resolution of symptoms, except for mild arthralgia in the second to fourth fingers of the right hand, was observed 61 days after discontinuation of MMI. Although the pathogenesis is unclear, the positive drug lymphocyte stimulation test for MMI and the several weeks before the onset of AAS suggested involvement of a type IV allergic reaction. Based on a discussion of definitive treatment for Graves’ disease, radioactive iodine ablation with 131I, which was selected by the patient, was performed and improved her thyroid function. Our case demonstrates the importance of awareness regarding AAS, which is a rare and under-recognized, but life-threatening adverse effect of antithyroid agents.
Clinicians should be aware of the possibility of developing antithyroid arthritis syndrome (AAS) in patients treated with antithyroid medications, which can lead to severe migratory polyarthritis.
Prompt cessation of the antithyroid agent is essential for the resolution of AAS.
Anti-neutrophil cytoplasmic antibody (ANCA) negativity is needed to differentiate from antithyroid agent-induced ANCA-associated vasculitis, which shows arthritis similar to AAS.
Jens Otto Lunde JørgensenDepartment of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark Department of Clinical Medicine, Aarhus University, Aarhus University Hospital, Aarhus, Denmark
This case report describes a rare presentation of ectopic Cushing’s syndrome (CS) due to ectopic corticotropin-releasing hormone (CRH) production from a medullary thyroid carcinoma (MTC). The patient, a 69-year-old man, presented with symptoms of muscle weakness, facial plethora, and easy bruising. An inferior petrosal sinus sampling test (IPSS) demonstrated pituitary adrenocorticotrophic hormone (ACTH) secretion, but a whole-body somatostatin receptor scintigraphy (68Ga-DOTATOC PET/CT) revealed enhanced uptake in the right thyroid lobe which, in addition to a grossly elevated serum calcitonin level, was indicative of an MTC. A 18F-DOPA PET/CT scan supported the diagnosis, and histology confirmed the presence of MTC with perinodal growth and regional lymph node metastasis. On immunohistochemical analysis, the tumor cell stained positively for calcitonin and CRH but negatively for ACTH. Distinctly elevated plasma CRH levels were documented. The patient therefore underwent thyroidectomy and bilateral adrenalectomy. This case shows that CS caused by ectopic CRH secretion may masquerade as CS due to a false positive IPSS test. It also highlights the importance of considering rare causes of CS when diagnostic test results are ambiguous.
Medullary thyroid carcinoma may secrete CRH and cause ectopic CS.
Ectopic CRH secretion entails a rare pitfall of inferior petrosal sinus sampling yielding a false positive test.
Plasma CRH measurements can be useful in selected cases.
Farhana SharifDepartment of Paediatrics, Regional Hospital Mullingar, Co. Westmeath, Ireland Department of Paediatrics, Royal College of Surgeons in Ireland, Dublin, Ireland School of Medicine, University College Dublin, Dublin, Ireland
Graham Robert LeeSchool of Medicine, University College Dublin, Dublin, Ireland Department of Clinical Biochemistry and Diagnostic Endocrinology, Mater Misericordiae University Hospital, Dublin, Ireland
Rare patients who have both thyroid-stimulating hormone (TSH) receptor-stimulating and -blocking antibodies can develop ‘pendulum swinging’ thyroid dysfunction. A 9-year-old girl with Down syndrome was treated with carbimazole for Graves’ disease. After 2 years of treatment, she became profoundly biochemically hypothyroid, and this persisted after carbimazole was discontinued. Low-dose L-thyroxine was commenced. This was subsequently also discontinued as biochemical hyperthyroidism developed. TSH receptor antibody bioassay identified both TSH receptor-stimulating and -blocking antibodies. Mild hyperthyroidism persisted and while consultations regarding definitive treatment were ongoing, medication was not recommenced. Thyroid function normalised spontaneously and she has remained euthyroid for the past 3 years. Previous reports have advised definitive treatment; however, our patient developed spontaneous remission which has been prolonged and definitive therapies have been avoided. It is not yet known how commonly this particular phenomenon occurs.
Rare patients who have both TSH receptor-stimulating and -blocking antibodies can switch between hyperthyroidism and hypothyroidism or vice versa during treatment with antithyroid drugs or thyroxine.
Metamorphic thyroid autoimmunity is more common in Down syndrome.
Switching between hyperthyroidism and hypothyroidism and back again is less commonly reported.
Definitive treatment such as radioactive iodine or thyroidectomy are usually recommended.
Prolonged remission was achieved off all medication, without recourse to definitive treatments.
Mpox (MPX) formerly known as monkeypox was declared a public health emergency of international concern, following an outbreak that commenced in May 2022. We report a case of subacute thyroiditis following MPX infection. To our knowledge, it is the first documented incidence of this complication in humans. A 51-year-old male, with a well-controlled human immunodeficiency virus (HIV) infection on antiretroviral therapy, was reviewed 3 weeks after a positive test for MPX. The acute skin lesions and initial systemic symptoms had resolved, but he described significant neck discomfort, fatigue, weight loss and night sweats. Blood tests showed a raised C-reactive protein, free T4 and suppressed thyroid-stimulating hormone. His thyroid antibodies were negative. He was treated initially with carbimazole and propranolol, pending exclusion of any other intercurrent infection. A chest radiograph was normal; blood cultures and a combined nose and throat swab for respiratory virus PCR testing were negative. Following this, he commenced a 2-week course of prednisolone; his symptoms resolved completely within 24 h of starting. He subsequently developed hypothyroidism, which was treated with levothyroxine. The clinical features, abnormal thyroid function, raised CRP and negative thyroid antibodies 3 weeks post-MPX positive test was consistent with viral subacute thyroiditis. This case demonstrates that, as described following other viral infections, MPX can cause subacute thyroiditis, which follows a similar course to the classic form of subacute thyroiditis. Clinicians should be aware of this potential endocrine complication when attending to patients with MPX.
Subacute thyroiditis can present following mpox virus infection.
Its course is similar to the classic form of subacute thyroiditis and steroids are effective.
It is important to exclude other concurrent infections prior to starting steroids, especially for patients who are immunosuppressed or in other high-risk groups.
An 11-year-old girl with past medical history of septic shock and multi-organ failure at age 5 presented to her primary care doctor with concern for pallor of the lips. Laboratory studies demonstrated low free thyroxine (T4) and normal thyroid-stimulating hormone (TSH). A referral to endocrinology was made where the patient was evaluated, and laboratory evaluation was repeated. The patient was asymptomatic and clinically euthyroid with a height consistent with her mid-parental height and was in mid- to late-puberty. The repeated laboratory evaluation demonstrated a pattern suggestive of primary hypothyroidism with low free T4 and an elevated TSH. However, the magnitude of elevation of TSH was less than expected, given the degree of lowering of free T4; therefore, central hypothyroidism was considered. Workup was initiated, and laboratory studies and MRI imaging confirmed an underlying diagnosis of panhypopituitarism in the setting of pituitary stalk interruption syndrome.
Pituitary stalk interruption syndrome is a rare but important cause of panhypopituitarism.
Central hypothyroidism should be suspected in patients with low free thyroxine with an inappropriate degree of elevation of thyroid-stimulating hormone.
Workup of central hypothyroidism should include multi-pituitary hormone assessment, and, if evident, MRI imaging should be done.
Adrenal insufficiency should be suspected in a hypotensive, critically ill patient who is failing to improve on standard-of-care therapy.
We report a case of a woman with a diagnosis of breast cancer who unintentionally started gaining weight, feeling tired, and constipated 44 weeks after the initiation of trastuzumab. Hypothyroidism secondary to an autoimmune thyroiditis associated with trastuzumab was diagnosed, the first case described in Portugal and the fourth case described worldwide. Our intention regarding the publication of this case report is to alert the clinicians treating people with trastuzumab that they should ask the patients about symptoms of hypothyroidism and should screen the thyroid function of the patients before, during, and after the initiation of trastuzumab.
Trastuzumab is a humanized MAB used in HER2-positive breast and gastric cancer.
Trastuzumab-associated autoimmune thyroid disease (AITD) is rare (incidence rate in an RCT of 0.3%).
Manifestations of autoimmune thyroiditis associated with trastuzumab resemble those of hypothyroidism in other clinical contexts, but the presence of goiter is highlighted as a reason for medical evaluation. Biochemically, it is characterized by an increased thyroid-stimulating hormone (TSH) with or without a low FT4/FT3, and sonographically with a pattern of thyroiditis.
The treatment consists of levothyroxine, in a dose of 1.6–1.8 µg/kg/day, with re-evaluation of the thyroid function in 4–6 weeks.
We report the first case of autoimmune thyroiditis secondary to trastuzumab in Portugal.
It is important to evaluate the thyroid function before, during, and after the initiation of this therapeutic agent.