Fever of Unknown Origin as a Sole Presentation of Subacute Thyroiditis in an Elderly Patient: A Case Report with Literature Review

Subacute Thyroiditis—Still a Diagnostic Challenge: Data from an Observational Study

Background: Subacute thyroiditis (SAT) is a relatively common cause of thyroid disease. However, only a few studies evaluating SAT have been published in recent years with varying diagnostic criteria. We evaluate the clinical presentation and long-term outcome of isotope scan-confirmed SAT. Methods: A retrospective study of 38 patients with isotope scan-confirmed SAT was performed at a single isotope department. All patients were contacted for long-term follow-up. Results: The female/male ratio was 1.4:1, and mean age was 47 ± 14 years and 62 ± 12 years in women and men, respectively (p = 0.002). Almost half of the cases (42%) occurred during the summer. The most common symptoms were neck pain (74%) and weakness (61%). Palpitations, weight loss, heat intolerance, and sweating appeared in 50%, 42%, 21%, and 21%, respectively. Only half of the patients reported fever. TSH level was low in all patients, and mean FT4 and FT3 level were about twice the upper limit of normal range. Elevated CRP and ESR occurred in the majority (88%) of patients. The mean time period between the first clinic visit and performing thyroid function tests was 8 ± 7 days. One-third of the patients initially received a diagnosis of upper respiratory tract infection (URI). NSAIDs and steroids were prescribed to 47% and 8% of patients, respectively. Long-term follow-up of 33.5 months (range 9–52) revealed that 25% remained with subclinical or overt hypothyroidism. Conclusions: These data demonstrate that although SAT is a common entity, there is still a significant delay in diagnosis, and in a third of our patients, the initial diagnosis was URI, with 25% developing long-term hypothyroidism.

The Old and the New in Subacute Thyroiditis: An Integrative Review

Subacute thyroiditis (SAT) is the most common cause of neck pain and thyrotoxicosis. Although this disease was recognized already by the end of the 18th century, new concepts regarding pathogenesis have emerged in recent years. Moreover, in the last two years, literature on SAT has increased significantly due to articles describing the possible connection with coronavirus disease 2019 (COVID-19). This integrative review depicts old and new concepts of this disease, proposing a detailed overview of pathogenesis, a practical approach to diagnosis and treatment, and a thorough description of the latest discoveries regarding the association of SAT with COVID-19.

Can Subacute Thyroiditis Be a Cause of Fever of Unknown Origin?

Subacute thyroiditis (SAT) is a self-limiting, painful, non-suppurative thyroid gland inflammation, which usually develops two to eight weeks after viral upper respiratory tract infections, accompanied by pain and fever. The thyroid gland is large, painful, and tender. It presents with fever, myalgia, arthralgia, weakness, and sore throat.

A 37-year-old male presented to medical ward with a history of fever for three weeks along with swelling of neck and difficulty in swallowing. The patient had features of hyperthyroidism. High-resolution ultrasonography (HRUSG) and thyroid scan were suggestive of thyroiditis. Later on, on follow-up, the patient developed hypothyroidism. He was managed with antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), and glucocorticoids, and he responded well to the above treatment. The index patient presented as a case of fever which on workup was found to be secondary to subacute thyroiditis (SAT).

Diagnostic value of nuclear medicine imaging and ultrasonography in subacute thyroiditis

OBJECTIVE

To analyze and compare the diagnostic value of nuclear medicine and ultrasonography in subacute thyroiditis.

METHODS

Sixty patients with subacute thyroiditis admitted to our hospital were included into the observation group, and 60 healthy controls who underwent physical examination in our hospital during the same period were enrolled into the control group. Examinations of nuclear medicine and ultrasonography were performed in the neck, and the results were compared between the two groups.

RESULTS

There were significant differences in the width and thickness of thyroid bilateral lobes between the two groups (P<0.05), and for patients in the observation group, the detection rates of nuclear medicine technique and ultrasonography were 98.33% and 95.00%, respectively. Both methods showed no significant difference in the detection rate of subacute thyroiditis (P>0.05).

CONCLUSION

Both nuclear medicine imaging and ultrasonography can provide clinical guidance for diagnosis and treatment of subacute thyroiditis.

[Clinical practice guidelines for acute and chronic thyroiditis (excluding autoimmune thyroiditis)]

Острые и хронические заболевания щитовидной железы занимают второе место по выявляемости после сахарного диабета. Всемирная организация здравоохранения отмечает ежегодную тенденцию к увеличению числа заболеваний щитовидной железы. В настоящих клинических рекомендациях будут рассмотрены вопросы этиологии, клинического течения, диагностики и лечения острых и хронических (за исключением аутоиммунного) воспалительных заболеваний щитовидной железы.Клинические рекомендации — это основной рабочий инструмент практикующего врача, как специалиста, так и врача узкой практики. Лаконичность, структурированность сведений об определенной нозологии, методов ее диагностики и лечения, базирующихся на принципах доказательной медицины, позволяют в короткий срок дать тот или иной ответ на интересующий вопрос специалисту, добиваться максимальной эффективности и персонализации лечения.Клинические рекомендации составлены профессиональным сообществом узких специалистов, одобрены экспертным советом Министерства здравоохранения РФ. Представленные рекомендации содержат максимально полную информацию, которая требуется на этапе диагностики острых и хронических тиреоидитов, этапе выбора тактики ведения пациентов с тиреоидитом, а также на этапе лечения пациента.Рабочая группа представляет этот проект в профессиональном журнале, посвященном актуальным проблемам эндокринологии, с целью повышения качества оказываемой медицинской помощи, повышения эффективности лечения острых и хронических тиреоидитов путем ознакомления с полным тестом клинических рекомендаций по острым и хроническим тиреоидитам (исключая аутоиммунный тиреоидит) максимально возможного количества специалистов в области не только эндокринологии, но и медицины общей (семейной) практики.

Subacute Thyroiditis: An Unusual Presentation of Fever of Unknown Origin Following Upper Respiratory Tract Infection

Patient: Male, 44-year-old

Final Diagnosis: Subacute thyroiditis

Symptoms: Fever

Medication: —

Clinical Procedure: None

Specialty: General and Internal Medicine