Subacute thyroiditis as a post-COVID-19 complication: a systematic review

Abstract

Introduction

The emergence of Subacute Thyroiditis (SAT) in the wake of COVID-19 has presented a unique set of challenges for clinicians and researchers. This study delves into the intricate interplay between COVID-19 and SAT, examining a wealth of cases from observational studies.

Methods

We conducted a comprehensive literature review utilizing PubMed/MEDLINE, EMBASE, and Scopus databases, encompassing studies available up to January 2, 2025. The search strategy incorporated a combination of keywords such as “Subacute Thyroiditis” and “COVID-19,” complemented by synonyms and Mesh terms. Relevant studies, investigating COVID-19-associated SAT were included.

Results

After a meticulous review of 964 papers, 46 records were included in the final analysis, consisting of 37 case reports and 9 case series. Our study, covered 75 individuals aged 18 to 85. Investigated patients presenting diverse symptoms, including anterior cervical pain and palpitations, displaying varying timelines from COVID-19 onset to SAT symptoms. Treatment approaches, involving prednisone and non-steroidal anti-inflammatory drugs (NSAIDs), led to recovery in many cases, but some individuals experienced a transition to hypothyroidism. The diagnostic and laboratory investigations across revealed diverse profiles, thyroid imaging findings, inflammatory markers, thyroid function tests, and the presence of anti-thyroid antibodies.

Conclusion

The complexity of SAT is emphasized, particularly in the context of COVID-19. The consistent trend toward recovery of thyroid function not only suggests potential treatment efficacy but also emphasizes the necessity for vigilant symptom monitoring, especially in individuals with a history of COVID-19. Future studies should further investigate the details of SAT post-COVID-19, improving approaches to diagnosis, treatment, and patient care.

Introduction

The global impact of COVID-19 extends beyond the acute respiratory symptoms, with emerging evidence pointing towards intriguing connections with various extrapulmonary manifestations.

Among these, Subacute Thyroiditis (SAT) has emerged as a noteworthy post-COVID-19 complication [1–3]. As individuals navigate the recovery phase from COVID-19, reports have surfaced indicating an increased incidence of SAT cases. Subacute thyroiditis, characterized by inflammatory changes in the thyroid gland, presents with distinct symptoms such as severe neck pain, palpation tenderness, and a small diffuse goiter [3, 4]. This inflammatory thyroid disorder is often accompanied by low-grade fever, fatigue, mild thyrotoxic manifestations, and elevated inflammatory markers.

The presence of ACE2 receptors, pivotal for SARS-CoV-2 cell entry, in the thyroid gland raises intriguing questions about a potential direct impact of the virus on thyroid function, leading to the development of SAT [5–7]. The recognition of thyroid involvement post-COVID-19 recovery emphasizes the need for vigilant monitoring of patients for potential endocrine complications during the convalescent phase.

While studies are underway to investigate these issues, a comprehensive study summarizing the available evidence is currently lacking. Thus, the aim of the current systematic review is to examine existing literature, synthesize available data, and provide a comprehensive overview of the relationship between COVID-19 and SAT.

Methods

Search strategy

We performed an extensive exploration of PubMed/MEDLINE, EMBASE, and Scopus databases to identify relevant studies available until January 2, 2025. The search employed the following terms: Subacute Thyroiditis and COVID-19, along with synonyms and MeSH terms. This study adhered to PRISMA statement for its design and reporting [8]. The protocol of this review was registered on the International Prospective Register of Systematic Reviews (PROSPERO) with the Registration ID: CRD42025634469.

Eligibility criteria

Studies were included if they complied with our predefined PECOS criteria (Table 1). Studies were excluded if they weren’t about subacute thyroiditis or if they were not post covid infection. Articles concentrating on post covid vaccination were also excluded.

Table 1.

The predefined eligibility criteria based on population, exposure, comparator, outcome, and study design (PECOS)

Population	Patients who developed SAT after or during COVID-19 infection.
Exposure	COVID-19 infection (confirmed via clinical, laboratory, or imaging methods).
Comparator	Variations in patient presentations (e.g., different timelines for SAT onset).
Outcome	Diagnostic findings and Recovery of thyroid function.
Study design	Case reports and case series examining the relationship between COVID-19 and SAT, including diagnostic, treatment, and patient outcomes.

Study selection

The collected records from the database searches were merged, and duplicates were removed through the utilization of EndNote X7 (Thomson Reuters, Toronto, ON, Canada). Two reviewers, K. Gh and H.Sh, conducted a thorough assessment of the records individually, utilizing the title/abstract and full-text screening process to exclude any publication not aligned with the study’s objectives.

Observational studies that investigated patients diagnosed with SAT following a COVID-19 infection were included.

Data extraction

Two reviewers, namely K. Gh and A.S, collaboratively devised a structured data extraction form and proceeded to extract information from all qualifying studies. Discrepancies were addressed through mutual agreement. Data extraction encompassed the collection of the following variables: First Author, Year of study, Country, Gender, personal and family history, Main complaint, COVID-19 status, period of time from COVID-19 diagnosis to SAT symptoms, medical history and physical examination, SAT treatment, follow-up, and outcome of SAT, COVID-19 diagnosis method, chest imaging and thyroid imaging, Thyroid Function Tests (e.g. Erythrocyte Sedimentation Rate (ESR), C-Reactive Protein (CRP), Thyroid Function Tests (TFTs)), Anti-thyroid antibodies, and the association between SAT and COVID-19.

Quality assessment

The JBI Critical Appraisal tools for case report [9] and case series [10] were used to measure the risk of bias for each of the included studies by two independent reviewers (K.G., S.H). The included studies were judged to have a low, unclear, or high risk of each type of bias mentioned and a graphical representation of the data was created using the robvis shiny web app [11].

Results

Figure 1 illustrates the flow diagram of the systematic review process. This thorough review included a total of 46 records that were included in the final results, comprising 37 case reports and 9 case series.

Fig. 1.

Flow chart of study selection for inclusion in the systematic review and meta-analysis

In our systematic review, we observed a diverse range of subacute thyroiditis cases post-COVID-19, spanning various countries and demographics. The age range across cases varied from 18 to 85, showcasing a broad spectrum of individuals affected by this post-COVID-19 complication. Examining gender representation, the cases encompassed a mix of both male and female patients. This diversity was evident in both the individual case reports and the compiled case series. The international scope of reported cases reflects the global impact of subacute thyroiditis as a potential complication of COVID-19. As for the total number of patients, our analysis included 75 individuals, with 37 patients documented in case reports and an additional 38 patients in case series (Table 2).

Table 2.

Basic characteristics of included studies

Author/Year	Country	Study design	Age	Gender
Ruggeri,2020 [12]	Italy	Case report	43	Female
Khatri,2020 [13]	USA	Case report	41	Female
Mattar,2020 [14]	Singapore	Case report	34	Male
Ruano,2020 [15]	Spain	Case report	28	Female
Mehmood,2020 [16]	USA	Case report	29	Female
Barrera,2020 [17]	Mexico	Case report	37	Female
Ippolito,2020 [18]	Italy	Case report	69	Female
Guven,2020 [19]	Turkey	Case report	49	Male
Chakraborty,2020 [20]	India	Case report	58	Male
Brancatella,2020 [21]	Italy	Case report	18	Female
Kalkan,2020 [22]	Turkey	Case report	41	Female
Ashraf,2021 [23]	Pakistan	Case report	58	Male
Chong,2020 [24]	USA	Case report	37	Male
Davoodi,2021 [25]	Iran	Case report	33	Male
LopezFrias,2021 [26]	Spain	Case report	36	Female
Feghali,2021 [27]	USA	Case report	38	Female
Ramsay,2021 [28]	USA	Case report	51	Female
Kalcakosz,2022 [29]	Hungary	Case report	31	Female
Mathews, 2021 [30]	USA	Case report	67	Male
Nham, 2023 [31]	Korea	Case report	27	Female
Dolkar, 2022 [32]	USA	Case report	55	Female
Elawady,2022 [33]	Egypt	Case report	33	Female
Henke, 2023 [34]	Switzerland	Case report	44	Female
Jakovac, 2022 [35]	Croatia	Case report	85	Male
Martínez, 2021 [36]	Mexico	Case report	64	Male
Ragab, 2022 [37]	Emirates	Case report	40	Male
Al-Shammaa, 2020 [38]	Iraq	Case report	53	Female
Sato, 2021 [39]	Japan	Case report	31	Female
Martin, 2020 [40]	Spain	Case report	46	Female
De Souza, 2022 [41]	Brazil	Case report	51	Female
Salehi, 2022 [42]	Iran	Case report	55	Male
Tjønnfjord,2021 [43]	Norway	Case report	40	Male
Ullah,2022 [44]	Pakistan	Case report	30	Male
Whiting,2021 [45]	USA	Case report	49	Male
Chavez-Flores, 2024 [46]	USA	Case report	51	Male
Sakai, 2024 [47]	Japan	Case report	77	Female
Zeqiraj, 2024 [48]	Ukraine	Case report	40	Male
Sohrabpor,2020 [49]	Iran	Case series with 6 patients	Mean age: 37	Male/Female
Brancatella,2020 [50]	Italy	Case series with 4 patients	Mean age: 35	Male/Female
Abreu,2021 [51]	Brazil	Case series with 3 patients	Mean age: 35	Male/Female
Baykan,2021 [52]	Turkey	Case series with 5 patients	Mean age: 39	Male/Female
Semikov,2021 [53]	Russia	Case series with 2 patients	Mean age: 42	Male/Female
ÜNÜBOL, 2021 [54]	Turkey	Case series with 2 patients	Mean age: 47	Male/Female
Sadiku, 2024 [55]	Kosova	Case series with 7 patients	Mean age: 40	Male/Female
Aini, 2023 [56]	Indonesia	Case series with 7 patients	Mean age: 51	Male/Female
Ganie,2024 [57]	India	Case series with 2 patients	Mean Age: 60	Male

Overview of COVID-19-Associated sat cases in case reports

Table 3 presents a comprehensive overview of clinical presentations, treatment courses, and outcomes in individuals with COVID-19-associated SAT, as documented in various case reports. The main complaints reported by patients include a spectrum of symptoms such as anterior cervical pain, tremors, palpitations, worsening neck mass, unintentional weight loss, fatigue, and heat intolerance. The timeline from COVID-19 to SAT symptoms varies, with cases reporting past COVID-19 status and ongoing symptomatic presentations. Thyroid symptoms encompassed manifestations like mild tremors, painful goiter, tender lymph nodes, and tachycardia. Clinical examinations revealed diverse findings, including asymmetric goiter, hard/tender regions, and palpable lymph nodes.

Table 3.

Clinical presentation, treatment courses, and Outcome of Covid-19 associated SAT of case reports

Author/Year	Main complaint	Covid-19 Status	Time from covid-19 to SAT symptoms	Thyroid Symptoms	Examination	SAT Treatment	Follow Up	Outcome
Ruggeri,2020 [12]	Anterior cervical pain, tremors, palpitations	Past	42days	N/A	Mild tremors, painful goiter, tender lymph nodes	Prednisone	4 weeks: normalization of thyroid function	Recovered
Khatri,2020 [13]	Worsening neck mass, associated symptoms	Past	4weeks	Unintentional weight loss, fatigue, heat intolerance, tremors	Tender thyroid, no lymphadenopathy, tachycardia	Ibuprofen and Prednisone	1 week: TFT improvement	Recovered
Mattar,2020 [14]	Fever, dry cough, refractory neck pain, tachycardia	Ongoing symtomatic	9days	Tachycardia	Asymmetric goiter, hard/tender regions, few lymph nodes	Prednisolone Beta-blocker	45 days: complete resolution	Recovered
Ruano,2020 [15]	Diarrhea, abdominal pain, fever, neck pain, asthenia	Asymptomic and 7 days later was resolved	13days	Sinus tachycardia at 150 bpm	Grade 2 goiter, excruciating palpation, no eye/skin lesions	Aspirin, Propranolol	2 days: symptom improvement	Recovered
Mehmood,2020 [16]	Intermittent fever, odynophagia, swallowing difficulties	Past	7weeks	Tachycardia, shortness of breath, unintentional weight loss	Anterior neck tenderness, palpable left thyroid lobe, fine tremors	Oral Prednisone, Atenolol	5 days: CRP level downtrending	Recovered
Barrera,2020 [17]	Severe neck pain, irradiation to jaw, ear, and fatigue	Past	30days	N/A	Moderately enlarged tender thyroid, neck adenopathy	N/A	10 weeks: complete recovery	Asymptomatic
Ippolito,2020 [18]	Palpitations, insomnia, agitation, clinically stable	Ongoing symptomatic	5days	Palpitations, insomnia, agitation	Neck painful/swollen, hyperemic tonsils	Methimazole and Steroid	24 h: symptoms improved, total relief in 2 weeks	Recovered
Guven,2020 [19]	Sore throat, swallowing difficulty, high fever	Past	10 days	High-grade fever with tachycardia, increased stools	Tender swelling, normal temperature, resembling enlarged thyroid	Methylprednisolone	3 days: symptomatic, 10 weeks asymptomatic	Recovered
Chakraborty,2020 [20]	Throat pain, increased stool frequency, low-grade fever	Ongoing	N/A	Palpitations, fatigue	Increased heart rate, markedly painful/enlarged thyroid	Combination of Analgesics, Favipiravir, Azithromycin, Zinc, Vitamin C, Oral Prednisolone	One month: asymptomatic, abnormal lab tests	Hypothyroid
Brancatella,2020 [21]	Sudden fever, palpitations, anterior neck pain to jaw	Past	15 days	N/A	Erythematous pharyngitis, tender thyroid, painful TMJ	IV Dexamethason, Naproxen, followed by Prednisolone	5 days after Methimazole: worsened, 10 days after steroid: improved	Recovered
Kalkan,2020 [22]	Fever and neck pain	Ongoing, asymptomatic tic	N/A	N/A	Tender thyroid, warmth, palpitation, heat intolerance, unintentional weight loss	Aspirin and Propranolol	1 week: asymptomatic, lower markers than before	Improved
Ashraf,2021 [23]	Fever, tender thyroid gland, odynophagia	Positive	6 days	Sinus tachycardia	Enlarged thyroid, sensitive to palpation	Corticosteroid therapy Dexamethason, Oral Prednisone	Initial recovery but became hypothyroid later, started levothyroxine	Recovered
Chong,2020 [24]	Neck pain, fatigue, chills	Positive	1 month	Sinus tachycardia	Severely tender neck (left), no thyroid enlargement	NSAID and Propranolol, Omeprazole	2 days: Neck pain and fever disappeared	Recovered after 70 days
Davoodi,2021 [25]	Fever, sore throat, lethargy, slight neck tenderness	Positive	10 days	Palpitation	Normal, no proptosis	N/A	1 week: Asymptomatic	Recovered
LopezFrias,2021 [26]	Anterior neck pain, low-grade fever, fatigue	Positive	45days	Palpitation	Tender neck swelling, enlarged tonsil with white exudate	Propranolol, Non-Steroidal Anti-inflammatory Medication	37 days: TFT and inflammatory markers normal	Normalized in 3 months
Feghali,2021 [27]	Persistent palpitations, insomnia	Positive	6weeks	Tachycardia	Sinus tachycardia, prolonged QTc, thyromegaly with tenderness	Methylprednisolone	N/A	Hypothyroid in 3 weeks
Ramsay,2021 [28]	Chest pain, palpitation, difficulty swallowing, anterior neck pain	Positive	23days	Fever, fatigue, myalgia, palpitation, tremor	Palpation with pain, no nodules, difficult swallow	Methimazole, Prednisone	Recovered completely in 3 weeks	Recovered
Kalcakosz,2022 [29]	Severe neck pain, tenderness radiating to jaw	Past	5 weeks	Weight loss, fatigue, diarrhea	Distal tremor, generalized diaphoresis	Naproxen and Propranolol for several weeks	Hypothyroid after 3 weeks	Recovered
Mathews, 2021 [30]	Weight loss, fatigue, diarrhea	Ongoing	N/A	Pricking chest pain, fever	No apparent thyroid enlargement, left lobe tenderness	Ceftriaxone, Azithromycin, Dexamethasone, Remdesivir, Amlodipine, Enoxaparin, Famotidine	Asymptomatic in 7 weeks	Recovered
Nham, 2023 [31]	Fever, sore throat, frontal headache	Past	2 weeks	Tachycardia, abdominal pain, hypertension, respiratory failure	Sore, soft neck, increased pulse (134 bpm), tremors	Prednisone and Ibuprofen	Hypothyroid in 1 month	N/A
Dolkar, 2022 [32]	Abdominal pain, pulmonary embolism	Ongoing	N/A	Neck swelling, pain, fever, malaise, myalgia, tachycardia	Temp 37.8 °C, painful/hard/enlarged thyroid, neck pain radiated to jaw	Prednisone	N/A	Recovered
Elawady,2022 [33]	Anterior neck pain for 4 weeks	Past	2 weeks	Neck pain, headache, asthenia, insomnia, tremor, weight loss, palpitations	Grade 1 goiter, significant tenderness	High oxygen flow therapy, Noradrenaline, Volume substitution	N/A	Euthyroid after 6 weeks
Henke, 2023 [34]	Neck pain, headache, asthenia, insomnia, hand tremor, weight loss, palpitations	Ongoing	2 weeks	Hands tremor, Weight loss, Palpitation	Painful goiter in left lobe, no palpable lymph nodes	Prednisone	Symptoms disappeared within a day, other symptoms within 2 weeks	Recovered
Jakovac, 2022 [35]	Unconsciousness, tachypnea, tachycardia, hypotension, cyanosis	Ongoing	N/A	Tachycardia	Tender thyroid, normal vital signs	Celecoxib, Acetaminophen/Paracetamol	Within a week FT4 decreased, TSH detectable within a month	Recovered
Martínez, 2021 [36]	Chest pain	Past	4 weeks	Chest pain	Diffuse tenderness, no thyroid enlargement, normal vital signs	Beta-Blockers and Analgesics	Overt thyrotoxicosis to subclinical, back to overt in 2 months	Recovered
Ragab, 2022 [37]	Sore throat, left-sided neck pain, difficulty swallowing	Past	5 months	Right-sided neck pain, sore throat	Mild tremors, painful goiter, tender lymph nodes	NSAIDs, Prednisolone	Abdominal pain resolved with famotidine, TSH/FT4 normalized	Recovered
Al-Shammaa, 2020 [38]	Palpitations, sweating, agitation, neck pain past 3 days	Past	10 days	Palpitations, sweating, agitation	Tender thyroid, no lymphadenopathy, tachycardia	Oral Prednisone + NSAIDs	Symptoms, exam, TSH normalized in 2 weeks, steroids tapered	Recovered after 6 weeks
Sato, 2021 [39]	Low-grade fever	Ongoing	0	Fever	Asymmetric goiter, hard/tender regions, few lymph nodes	NSAIDs + Prednisolone	Thyroid function and inflammation regressive in 7 days, euthyroid in 6 weeks	Recovered
Martin, 2020 [40]	Neck pain to ear, then spreading to thyroid lobe	Past	N/A	Low-grade fever, malaise, insomnia	Grade 2 goiter, excruciating palpation, no eye/skin lesions	Aspirin + Propranolol	Fulminant deterioration, mechanical ventilation	Recovered
De Souza, 2022 [41]	Odynophagia, malaise, headache, chills for 5 days	Positive	0	Odynophagia	Anterior neck tenderness, palpable left thyroid lobe, fine tremors	Prednisolone	Discharged with full relief after 3 days	Recovered
Salehi, 2022 [42]	Diffuse neck pain, severe coughs, hot flashes	Past	15 days	Diffuse neck pain, hot flashes	Moderately enlarged tender thyroid, neck adenopathy	Ibuprofen, Prednisone, Propranolol	Symptoms started to control after 3 weeks	Recovered
Tjønnfjord,2021 [43]	Fever, dysphagia, headache, dry cough, dyspnea, myalgia	Past	6 weeks	Myalgia, fever	Neck painful/swollen, hyperemic tonsils	Synthroid	Fully recovered after 10 weeks	Recovered
Ullah,2022 [44]	ED with 3 days of neck and chin pain, palpitations, anxiety	Past	16 days	Palpitations, anxiety, tachycardia, hyperhidrosis	Tender swelling, normal temperature, resembling enlarged thyroid	Prednisone	Monthly follow-up, normal after 3 months	Recovered
Whiting,2021 [45]	Six-month history of fatigue, weight gain, constipation	Past	6 months	Fatigue, constipation, weight gain, dry skin, myalgia	Increased heart rate, markedly painful/enlarged thyroid	Ibuprofen and Prednisone	Symptoms disappeared in a week, tapered medication	Recovered
Chavez-Flores, 2024 [46]	Acute-onset palpitations and shortness of breath	Past	1 month	Tachycardia, Fever	Temperature of 37.4 °C, High blood pressure of 154	Beta-blocker, NSAIDs	Asymptomatic after 1 month, TFTs to normal range in 2 month	Subclinical hyperthyroidism
Sakai, 2024 [47]	Night sweats, Skin rash, Diarrhea	Ongoing	1 month	Headache, Palpitation, Nocturnal Fever, Fatigue, Anorexia and significant weight loss	Slight enlargement and mild tenderness of the thyroid	Beta-blocker, NSAIDs	Asymptomatic after 1 week, TFTs to normal range in 1 month	Recovered
Zeqiraj, 2024 [48]	Fever and chills, Fatigue, Sore throat	Ongoing	13 Days	Sweating, Tachycardia	Slight Tenderness of the thyroid	Levothyroxine, Selenium	Two times infection with SARS-CoV-2 with the interval of 17 months, after full recovery each time the lab tests showed subclinical hypothyroidism with the suspicion of Hashimoto’s thyroiditis,	Hypothyroid

Treatment modalities consisted of medications like prednisone, ibuprofen, beta-blockers, antithyroid drugs, and a combination of analgesics, antivirals, and anti-inflammatory agents. The follow-up durations ranged from days to weeks, indicating the variable timelines for symptom resolution and recovery. Notably, the majority of patients recovered fully, while some cases transitioned to hypothyroidism.

Overview of COVID-19-associated sat cases in case series

Table 4 serves as a comprehensive overview of case series focusing on COVID-19-associated SAT. Within this context, patients manifested an array of symptoms, including fever, palpitations, and neck pain, presenting within distinct time frames following the onset of COVID-19. A prevailing observation was the occurrence of enlarged and tender thyroid glands. Treatment strategies prominently featured the administration of prednisolone and non-steroidal anti-inflammatory drugs (NSAIDs), resulting in a notable recovery trajectory, with thyroid function normalization achieved over variable durations.

Table 4.

Clinical presentation, treatment courses, and Outcome of Covid-19 associated SAT of case series

Author/Name	Patient Number	Chief Complaint	Time from Covid-19 to SAT Symptoms	Thyroid symptoms	Examination	SAT treatment	Follow up	Outcome
Sohrabpor, 2020, Iran [49]	1	Fever, fatigue, palpitations, and anterior neck pain	30 days	Fatigue, palpitations	Markedly painful, tender, and slightly enlarged thyroid gland	Prednisolone	1 week: Symptoms gone; 1 month: Normal TFTs.	Recovered
	2		30 days	Fatigue, palpitations	Markedly painful, tender, and slightly enlarged thyroid gland	Prednisolone	1 week: Symptoms gone; 1 month: Normal TFTs.	Recovered
	3		30 days	Fatigue, palpitations	Markedly painful, tender, and slightly enlarged thyroid gland	Prednisolone	1 week: Symptoms gone; 1 month: Normal TFTs.	Recovered
	4		30 days	Fatigue, palpitations	Markedly painful, tender, and slightly enlarged thyroid gland	Prednisolone	1 week: Symptoms gone; 1 month: Normal TFTs.	Recovered
	5		30 days	Fatigue, palpitations	Markedly painful, tender, and slightly enlarged thyroid gland	Prednisolone	1 week: Symptoms gone; 1 month: Normal TFTs.	Recovered
	6		30 days	Fatigue, palpitations	Markedly painful, tender, and slightly enlarged thyroid gland	Prednisolone	1 week: Symptoms gone; 1 month: Normal TFTs.	Recovered
Brancatella, 2020, Italy [50]	1	Neck pain radiated to the jaw, asthenia and fever	16 days	Palpitations	N/A	Prednisone	Atrial fibrillation cardioverted; symptoms vanished, asymptomatic at 45 days with normal thyroid and inflammatory markers.	Recovered
	2	Neck pain radiating to the jaw associated with asthenia, palpitations and sweating	30 days	Palpitations and sweating	N/A	Prednisone and propranolol	Neck pain and fever resolved in 3 days; asymptomatic at 2 weeks. Inflammatory markers normal at 33 days, but TFT revealed subclinical hypothyroidism.	Hyperthyroidism
	3	Neck pain radiating to the jaw and to the right ear.	36 days	Palpitations, tachycardia, and sweating	N/A	Ibuprofen	Asymptomatic at 2 weeks; inflammatory markers normal at 46 days. TFT indicated subclinical hypothyroidism, initiating low-dose levothyroxine.	Hypothyroidism
	4	Severe neck pain radiated to the jaw, fever, palpitations, anxiety	20 days	Insomnia, anxiety and weight loss	N/A	Prednisone	Neck pain and fever gone in days; at 2 weeks, asymptomatic with normal inflammatory markers and thyroid function.	Recovered
Abreu,2021 [51]	1	Mild pain in the anterior cervical region and mild fever	28 days	N/a	N/A	Prednisone (15 mg)	Asymptomatic in 4 days	Recovered
	2	Asymptomatic	10 days	N/a	N/A	Prednisone	Laboratory tests back to normal range in 18 days	Recovered
	3		26 days	N/a	N/A	N/a	Normal follow up ultrasound in 2 weeks	Recovered
Baykan, 2021 [52]	1	Fatigue, strong neck pain radiating to the jaw and right ear	18 days	N/a	N/A	NSAI therapy (not effective) followed by Prednisolone (40 mg gradually decreased dose) and corticosteroid therapy	Thyroid function tests returned to normal in 6 weeks	Recovered
	2	Neck pain, tachycardia, sweating, and palpitation	22 days	Tachycardia, sweating, and palpitation	N/A	NSAI therapy (not effective) followed by Prednisolone (40 mg gradually decreased dose)	Asymptomatic in 4 weeks	Recovered
	3	Palpitation, fever, fatigue, and strong neck pain	25 days	Palpitation	N/A	Prednisolone (40 mg gradually decreased dose)	Normalized laboratory tests in 5 weeks	Recovered
	4	Fatigue and anterior neck pain	20 days	N/a	N/A	NSAI therapy (not effective) followed by oral steroid treatment	Asymptomatic in 5 weeks	Recovered
	5	Tachycardia and mild fever and neck pain	24 days	Tachycardia	N/A	Oral steroid treatment	Thyroid function tests normalized in 5 weeks	Recovered
Semikov, 2021 [53]	1	Neck pain radiating to the lower jaw and right ear, fever, later swelling	Ongoing	Myalgia, palpitation, sweating, tachycardia	Pronounced swelling without changes in the skin, hard thyroid gland and sharply painful at palpation, no palpate lymph node	N/a	Prednisone 30 mg per day for 4weeks, reduction in the dosage by 5 mg weekly	Recovered
	2	Neck pain, fever	30 days	Palpitation, tachycardia	Hard thyroid gland, painful at palpation, no palpable lymph nodes	Prednisone 30 mg per day for 4 weeks, reduction in the dosage by 5 mg weekly, symptomatic therapy of thyrotoxicosis	Normalized laboratory tests and physical examinations in 5 weeks	Recovered
ÜNÜBOL,2021 [54]	1	Severe pain and swelling on the right anterior side of neck for two weeks, which radiated to the right ear, fatigue and myalgia for one week	4 weeks	Myalgia, fatigue	The patient’s thyroid gland was painful, tender, and palpable	550 mg of oral naproxen sodium twice a day	Pain vanished in two days, other symptoms alleviated in ten. TFTs and inflammatory markers (ESR, CRP) normalized after four weeks.	Recovered
	2	Fatigue, myalgia, backpain, headache, and anterior neck pain for five weeks	4 weeks	Fatigue, myalgia	Painful, tender, and large thyroid gland	550 mg of oral naproxen sodium twice a day	Continued Naproxen sodium treatment for four weeks. Subsequently, TFTs and inflammatory markers (ESR, CRP) normalized.	Recovered
Sadiku, 2024 [55]	1	Neck pain, fever, fatigue, odynophagia, headache	30 days	Fatigue, neck pain	Tenderness in the thyroid gland	Prednisolone, Indomethacin, Propranolol	N/A	Recovered
	2		30 days		Soft gland but tenderness in the thyroid gland	Prednisolone, propranolol	N/A	Recovered
	3		5 days		No nodularity, tenderness in the thyroid gland	Prednisolone, propranolol	N/A	Recovered
	4		7 days		Soft gland but painful in palpation	Indomethacin	N/A	Recovered
	5		14 days		No nodularity, tenderness in the thyroid gland	Prednisolone, propranolol	N/A	Recovered
	6		30 days		Tenderness in the thyroid gland	Indomethacin	N/A	Recovered
	7		7 days		Soft gland but painful in palpation	Prednisolone, propranolol	N/A	Recovered
Aini, 2023 [56]	1	Fever, Cough, Palpitation	N/A	Palpitation	N/A	Propylthiouracil, Propranolol, dexamethasone, Prednisolone	N/A	Recovered
	2	Weight loss, Palpitation, Cough	N/A	Weight loss, Tachycardia	N/A	Methimazole, Propranolol, Dexamethasone	N/A	Recovered
	3	Fever, chest pain and tremors	3 months	Weight loss, tremor, anxiety, sleep disturbance, fatigue	N/A	Prednisolone, propranolol	N/A	Recovered
	4	Dyspnea, palpitations, weakness, and weight loss	N/A	Palpitations, weight loss, sleep disturbances	N/A	Methimazole, Propranolol, Dexamethasone	N/A	Recovered
	5	Shortness of breath, cough, fever and chest palpitations	N/A	Palpitation	N/A	Prednisolone, propranolol	N/A	Expired
	6	Dyspnea, Palpitation	N/A	Palpitation	N/A	Prednisolone, Bisoprolol	N/A	Recovered
	7	Fever, Cough, Dyspnea	N/A	Palpitation	N/A	Prednisolone, propranolol	N/A	Recovered
Ganie,2024 [57]	1	Neck pain, Fever	Ongoing	Neck pain, Sweating, Palpitation, Tremor	Tachycardia and tenderness in thyroid gland	Beta Blocker, NSAID	Asymptomatic in 6 weeks	Recovered
	2	High-grade Fever	Ongoing	Palpitation and Tremors, High grade fever	Tachycardia, Hyperhidrosis, Tender and enlarged Thyroid gland	Beta Blocker, Prednisolone	Asymptomatic in 6 weeks	Recovered

Laboratory investigations in COVID-19-associated sat in case reports

Table 5 provides an extensive overview of the diagnostic and laboratory investigations conducted in individuals with COVID-19-associated SAT, as reported in various case reports. The diagnostic information includes the method of COVID-19 diagnosis, chest imaging findings, thyroid imaging details, and laboratory parameters. The cases presented diverse diagnostic profiles, reflecting the heterogeneity of COVID-19-associated SAT.

Table 5.

Diagnostic and laboratory investigation of Covid-19 associated SAT information of case reports

Author/Year	Covid-19 Diagnosis	Chest imaging	Thyroid Imaging	ESR (mm/h)	CRP (mg/L)	TFTs	Anti Thyroid Antibody
Ruggeri,2020 [12]	Serological testing	Normal	Diffuse enlarged thyroid, reduced 99mTc uptake.	N/A	N/A	Low TSH, High FT3, High FT4	Negative
Khatri,2020 [13]	RT − PCR	Normal	Heterogeneous thyroid, patchy hypoechoic areas.	107	36.4	Low TSH, High FT3, High FT4	TPOAb+
Mattar,2020 [14]	RT − PCR	Normal	Absence of uptake in thyroid, heterogeneously enlarged.	N/A	122	Low TSH, High FT3, High FT4	Negative
Ruano,2020 [15]	RT − PCR	N/A	No radioactive iodine uptake.	116	N/A	Undetectable TSH, High FT4	Negative
Mehmood,2020 [16]	RT − PCR	N/A	Enlarged hypoechoic thyroid, decreased vascularity.	84	44	Low TSH, High FT3, High FT4	Negative
Barrera,2020 [17]	RT − PCR	N/A	Bilateral infiltrates.	72	66	Low TSH, High FT3, High FT4	Negative
Ippolito,2020 [18]	RT − PCR	Ground glass (SARS-CoV-2)	Diffuse bilateral hypoechoic areas.	N/A	N/A	Low TSH, High FT4, High FT3 (Biological Range)	Negative
Guven,2020 [19]	RT − PCR	Reticulonodular density, ground glass (SARS-CoV-2)	Patchy infiltrations and hypoechoic areas.	80	7.69	Low TSH, High FT3, High FT4, Detectable Low Tg	Negative
Chakraborty,2020 [20]	RT − PCR	N/A	Poor radiotracer uptake, diffuse enlargement.	110	16.6	Low TSH, High FT3, High FT4	Negative
Brancatella,2020 [21]	RT − PCR	N/A	Diffuse enlargement, ill-defined hypoechoic areas.	90	101	Low TSH, Elevated FT4, FT3 in Biological Range	TgAb+
Kalkan,2020 [22]	RT − PCR	Normal	Heterogeneous thyroid with ill-defined hypoechoic areas.	134	101	Below Normal TSH, Elevated FT4, Elevated FT3	Negative
Ashraf,2021 [23]	RT − PCR	Glass appearance in both lungs	Diffuse heterogenous echotexture.	70	45	Below Normal TSH, Elevated FT4, Elevated FT3	N/A
Chong,2020 [24]	RT − PCR	N/A	Bilateral ill-defined hypoechoic areas.	50	20	Below Normal TSH, Elevated FT4, Elevated FT3	Negative
Davoodi,2021 [25]	RT − PCR	Bilateral peripheral ground glass	Mildly enlarged thyroid with no increased vascularity.	N/A	37.9	Below Normal TSH, Elevated FT4, Elevated FT3	Negative
LopezFrias,2021 [26]	RT − PCR	N/A	Diffusely enlarged with architectural distortion.	31	1.05	Suppressed TSH, Elevated FT4	TPOAb+
Feghali,2021 [27]	RT − PCR	N/A	Heterogeneously enlarged with hypoechoic areas.	N/A	N/A	Below Normal TSH, Elevated FT4	Negative
Ramsay,2021 [28]	RT − PCR	Normal	Micronodular thyroid, absent radionuclide uptake.	N/A	N/A	Decreased TSH, Elevated FT4, FT3 in Biological Range	Negative
Kalcakosz,2022 [29]	RT − PCR	N/A	Enlarged thyroid with ill-defined edges, solid nodule.	34	16.9	Decreased TSH, Elevated FT4	N/A
Mathews, 2021 [30]	RT − PCR	Bilateral infiltrates (Pneumonia)	Below-normal uptake values, diffuse hypoechoic areas.	37	5.3	Below Normal TSH, Elevated FT4	TPOAb+
Nham, 2023 [31]	RT − PCR	Normal	Enlarged thyroid with normal vascularization, global hypouptake.	N/A	31.13	Below Normal TSH, Elevated FT4, Elevated Total T3	Negative
Dolkar, 2022 [32]	RT − PCR	Initial X-rays: pneumonia. CT angiography: extensive pulmonary embolism.	Solid nodule in the left lobe, discrete vascularization.	N/A	N/A	Normal TSH, FT4, FT3	Negative
Elawady,2022 [33]	RT − PCR	N/A	Focal hypoechoic area, mild diffuse enlargement.	N/A	N/A	Below Normal TSH, Elevated FT4, Elevated Total T3	Negative
Henke, 2023 [34]	RT − PCR	N/A	Light diffuse enlargement with oedema, heterogeneous parenchyma.	98 (high)	first visit:78(high) 1week later:1.8 6 week later: 1.7	Below Normal TSH, Elevated FT4, Elevated T3, T4	High TG
Jakovac, 2022 [35]	RT-PCR	N/A	Diffuse hypoechoic areas, no remarkable uptake.	N/A	59.6(high)	Below Normal TSH, Elevated FT4, Elevated T3	Nucleocapsid protein low, Spike protein positive in granuloma
Martínez, 2021 [36]	RT − PCR	Multifocal pneumonia, ground-glass (SARS-CoV-2)	Enlarged thyroid, 4 mm nodules in isthmus.	N/A	N/A	Below Normal TSH, Elevated FT4, Elevated T3	Negative
Ragab, 2022 [37]	RT − PCR	N/A	Enlarged thyroid, mild hyperperfusion.	19	14.6	Below Normal TSH, Elevated FT4, Elevated T3	N/A
Al-Shammaa, 2020 [38]	RT-PCR	N/A	SARS-CoV-2 spike glycoprotein immunopositivity.	N/A	N/A	Suppressed TSH, Elevated FT4	TPOAb+
Sato, 2021 [39]	RT-PCR	Normal	Diffusely enlarged micronodular thyroid.	93	3.6	Below Normal TSH, Elevated FT4	TgAb+, TPOAb-
Martin, 2020 [40]	RT-PCR	N/A	Absent radionuclide uptake.	68	N/A	Decreased TSH, Elevated FT4, Elevated Total T3	TPOAb+
De Souza, 2022 [41]	RT-PCR	N/A	Diffuse hypoechoic areas, no remarkable uptake.	N/A	93.63	Normal TSH, FT4, FT3	Anti-thyroglobulin+, AntiTPO-
Salehi, 2022 [42]	RT − PCR	N/A	Enlarged thyroid with small hypoechoic solid nodules.	121	92.6	Below Normal TSH, Elevated FT4, Elevated T3	Negative
Tjønnfjord,2021 [43]	RT − PCR	Normal	Mild diffuse goiter with ill-defined hypoechoic area.	92	86	Below Normal TSH, Elevated FT4, Elevated T3	Negative
Ullah,2022 [44]	RT − PCR	N/A	Diffuse enlargement, hypoechogenicity, decreased vascularity.	88	12	Below Normal TSH, Elevated FT4, Elevated T3	N/A
Whiting,2021 [45]	RT − PCR	N/A	N/A.	N/A	N/A	Upper Normal TSH, Low FT4, Low FT3	TPOAb+
Chavez-Flores, 2024 [46]	RT-PCR	N/A	N/A	N/A	N/A	Low TSH, High FT4	Negative
Sakai, 2024 [47]	RT-PCR	Normal	Diffuse thyroid enlargement with poor blood flow, Hypoechoic areas from the left lobe through the isthmus to the central part of the right lobe	N/A	N/A	Low TSH, Elevated FT4	TPOAb+
Zeqiraj, 2024 [48]	RT-PCR	Pulmonary infiltration	Heterogeneous thyroid gland with ill-defined bilateral hypoechoic areas revealed	52	44.6	High TSH, Normal FT4	TPOAb+

Authors reported COVID-19 diagnosis through serological testing and RT-PCR. Chest imaging reveals a range of findings, including normal radiographs, ground-glass appearances indicative of SARS-CoV-2 infection, and multifocal pneumonia. Thyroid imaging showcases variations such as diffuse enlarged thyroid, heterogeneous parenchyma, ill-defined hypoechoic areas, and solid nodules.

Laboratory investigations include inflammatory markers such as ESR and TFTs, and the presence of anti-thyroid antibodies. The ESR and CRP values vary across cases, indicating the inflammatory nature of SAT. TFTs consistently show alterations in thyroid hormones, with low TSH and elevated FT3 and FT4 levels. Anti-thyroid antibodies, including TPOAb, TgAb, and TG, are reported in some cases, providing insights into the autoimmune component of SAT.

Laboratory investigations in COVID-19-associated SAT in case series

Table 6 outlines the diagnostic and laboratory investigations in case series of COVID-19-associated SAT. Patients were diagnosed using serological testing or RT-PCR for COVID-19, presenting with symptoms such as fever, palpitations, and neck pain. Imaging of the thyroid revealed characteristics such as diffuse enlargement, multiple hypoechoic areas, and absent vascularization. Laboratory markers, including ESR and CRP, exhibited variations. TFTs consistently indicated low thyroid-stimulating hormone (TSH), high free triiodothyronine (FT3), and high free thyroxine (FT4). Anti-thyroid antibodies were detected in some cases. The diverse presentations in this case series highlight the complexity of SAT in the context of COVID-19, emphasizing recovery trends marked by symptom resolution and thyroid function normalization.

Table 6.

Diagnostic and laboratory investigation of Covid-19 associated SAT information of case series

Author/Year	Patient Number	Covid-19 Diagnosis	Chest Imaging	Thyroid imaging	ESR (mm/h)	CRP (mg/L)	TFTs	Anti Thyroid Antibody
Sohrabpor,2020 [49]	1	Serological testing	Normal	Thyroid gland exhibits bilateral hypoechoic areas.	70	28	TSH: low FT3: high FT4: high	Negative
	2	Serological testing	Normal	Thyroid gland exhibits bilateral hypoechoic areas.	56	38	TSH: low FT3: high FT4: high	Negative
	3	Serological testing	Normal	Thyroid gland exhibits bilateral hypoechoic areas.	45	18	TSH: low FT3: high FT4: high	Negative
	4	Serological testing	Normal	Thyroid gland exhibits bilateral hypoechoic areas.	83	43	TSH: low FT3: high FT4: high	Negative
	5	Serological testing	Normal	Thyroid gland exhibits bilateral hypoechoic areas.	76	51	TSH: low FT3: high FT4: high	Negative
	6	Serological testing	Normal	Thyroid gland exhibits bilateral hypoechoic areas.	39	23	TSH: low FT3: high FT4: high	Negative
Brancatella,2020 [50]	1	RT-PCR	N/A	Enlarged thyroid with multiple hypoechoic areas and no vascularization in color Doppler.	74	11.2	TSH: low FT3: high FT4: high	TgAb detectable
	2	Serological testing	N/A	Neck ultrasound: diffuse hypoechoic areas, low vascularization in color Doppler. 9 m technetium scintiscan indicated absent thyroid uptake.	110	79	TSH: low FT3: high FT4: high	TgAb detectable
	3	Serological testing	N/A	Enlarged thyroid gland, multiple hypoechoic areas, absent vascularization in color Doppler.	N/A	N/A	TSH: low FT3: high FT4: high	N/A
	4	RT-PCR	N/A	Enlarged thyroid with multiple hypoechoic areas detected.	N/A	N/A	TSH: low FT3: high FT4: high	N/A
Abreu,2021 [51]	1	RT-PCR	N/A	Hypoechoic areas in the right thyroid lobe.	N/A	N/A	TSH: low, FT3: NA FT4: high	N/A
	2	RT-PCR	N/A	Irregular and hypoechoic areas observed in the right lobe during a screening neck ultrasound.	N/A	N/A	TSH: low, FT3: high FT4: high	N/A
	3	RT-PCR	N/A	Solid hypoechoic nodule identified in the left thyroid lobe.	N/A	N/A	TSH: low, FT3: NA FT4: high	N/A
Baykan, 2021 [52]	1	RT-PCR	N/A	Thyroid diffusely enlarged and hypoechoic.	52	36	TSH: low, FT3: elevated FT4: high	Negative
	2	RT-PCR	N/A	Multiple hypoechoic areas	72	48	TSH: low, FT3: high FT4: high	Negative
	3	RT-PCR	N/A	Detected an enlarged thyroid with multiple hypoechoic areas.	42	12	TSH: low, FT3: high FT4: high	Negative
	4	RT-PCR	N/A	Multiple hypoechoic areas	27	13.9	TSH: low, FT3: high FT4: high	Negative
	5	RT-PCR	N/A	Multiple hypoechoic areas	50	46.7	TSH: low, FT3: normal FT4: normal	Negative
Semikov,2021 [53]	1	Serological testing	signs of viral pneumonia involving 20% of the lung	Thyroid diffusely enlarged, with multiple hypoechoic areas in both lobes, and a pseudo-nodule in the right lobe.	32	N/A	TSH: low FT4: high	TPOAb +
	2	Serological testing	Pneumonia involving 15% of the lungs	Thyroid with clear contours, diffusely inhomogeneous echo structure, multiple hypoechoic areas, no nodal formations.	47	N/A	TSH: low FT4: high	TPOAb +
ÜNÜBOL, 2021 [54]	1	RT-PCR	N/A	Heterogeneous thyroid, decreased vascularity (right lobe), no naproxen uptake.	78	45	TSH: low FT4: normal FT3: normal	Negative
	2	RT-PCR	Normal	Heterogeneous thyroid with decreased vascularity (bilateral).	68	18.4	TSH: low FT4: normal	Negative
Sadiku,2024 [55]	1	RT-PCR	N/A	Heterogeneous parenchyma and central hypoechoic areas	57	104	TSH: low FT3: Slightly low T4: high	N/A
	2	RT-PCR	N/A	Heterogeneous parenchyma	80	60	TSH: low FT3: normal T4: high	N/A
	3	RT-PCR	N/A	Heterogeneous echo texture and central hypoechoic areas, enlarged thyroid	40	70	TSH: low FT3: high FT4: high	N/A
	4	RT-PCR	N/A	Central hypoechoic areas	50	90	TSH: low FT3: high FT4: high	N/A
	5	RT-PCR	N/A	Heterogeneous echo texture and central hypoechoic areas	N/A	100	TSH: low FT3: high FT4: high	N/A
	6	IgM and IgG SARS- CoV-2	N/A	Heterogeneous echo texture	55	88	TSH: low FT3: high FT4: high	N/A
	7	RT-PCR	N/A	Hypoechoic areas	N/A	60	TSH: low FT3: high FT4: high	N/A
Aini, 2023 [56]	1	RT-PCR	N/A	N/A	N/A	103.6	TSH: low FT4: high	N/A
	2	RT-PCR	N/A	N/A	N/A	-	TSH: low FT4: high	N/A
	3	RT-PCR	N/A	N/A	N/A	6.2	TSH: low FT4: high	N/A
	4	RT-PCR	N/A	N/A	N/A	51.8	TSH: low FT4: high	N/A
	5	RT-PCR	N/A	N/A	42	97.4	TSH: low FT4: normal	N/A
	6	RT-PCR	N/A	N/A	120	19.4	TSH: low FT4: normal	N/A
	7	RT-PCR	N/A	N/A	N/A	54.7	TSH: low FT4: normal	N/A
Ganie,2024 [57]	1	RT-PCR	Bilateral ground glass opacities	Heterogeneous thyroid, ill-defined hypoechoic areas and small cervical lymph nodes	86	148.24	TSH: low FT4: elevated FT3: elevated	Negative
	2	RT-PCR	Bilateral ground glass opacities	Heterogeneous thyroid, ill-defined hypoechoic areas	8	N/A	TSH: low FT4: normal FT3: normal	N/A

Quality assessment

The quality of the included studies was measured using the JBI Critical Appraisal tools, which showed a low risk of bias across most included case reports (Fig. 2) and moderate risk in case series studies (Fig. 3), with lack of information regarding adverse effect and lessons being the main concerns for bias in case reports (Fig. 4) and lack of information regarding consecutive, clinical demographic and complete are the main concerns in case series studies (Fig. 5).

Fig. 2.

The risk of bias for each case report study in each domain of the JBI tool

Fig. 3.

The risk of bias for each case series study in each domain of the JBI tool

Fig. 4.

Summary of the risk of bias in every domain of the JBI tool in case report studies

Fig. 5.

Summary of the risk of bias in every domain of the JBI tool in case series studies

Discussion

Principal findings

The significant findings emerging from the in-depth analysis of COVID-19-associated SAT cases underscore the importance of understanding the diverse clinical presentations, treatment approaches, and outcomes among affected individuals. Recognizing potential SAT symptoms, such as anterior cervical pain, tremors, palpitations, and neck pain, is vital, particularly in COVID-19. The variable timelines for symptom resolution and recovery underscore the need for personalized treatment approaches. Moreover, the consistent trend of recovery and normalizing thyroid function observed across case reports and case series suggests the potential effectiveness of treatments like Prednisone and NSAIDs, providing valuable insights for optimizing clinical strategies and informing healthcare planning.

Clinical implications

The comprehensive analysis of COVID-19-associated SAT cases reveals crucial insights with profound clinical implications for healthcare practitioners and policy decision-makers alike.

Diagnosis

The diverse clinical presentations observed in COVID-19-associated SAT cases highlight the need for a high index of suspicion among healthcare providers. Clinicians should consider SAT symptoms, such as anterior cervical pain, tremors, palpitations, and neck pain, especially in individuals with a history of COVID-19. Diagnostic strategies, including serological testing, should be tailored to promptly identify SAT and distinguish it from other thyroid disorders.

Treatment

The consistent recovery trend and normalization of thyroid function observed across cases suggest potential efficacy in treatments like prednisone and NSAIDs. Clinicians can leverage this information to optimize treatment strategies for COVID-19-associated SAT. Personalized approaches, considering the variable timelines for symptom resolution, are crucial. Additionally, the detection of anti-thyroid antibodies in some cases underscores the autoimmune component, guiding the exploration of targeted therapies.

Patient care

Vigilant monitoring for SAT symptoms is paramount, especially in individuals recovering from COVID-19. Healthcare providers should maintain awareness of the diverse manifestations, such as asymmetric goiter, palpable lymph nodes, and thyroid tenderness. Long-term follow-up is essential to identify cases transitioning to hypothyroidism and tailor ongoing care accordingly. These clinical implications aim to enhance the overall diagnostic accuracy, treatment effectiveness, and patient outcomes in the management of COVID-19-associated SAT.

Limitations

Despite the valuable insights gained from the analysis of COVID-19-associated SAT cases, certain limitations should be considered. The heterogeneity observed in clinical presentations, treatment responses, and outcomes across various case reports and case series introduces challenges in drawing definitive conclusions applicable to a broader population. Additionally, variations in diagnostic approaches, including COVID-19 testing and imaging modalities, may introduce biases and affect the accuracy of reported associations. The limited availability of long-term follow-up data for the majority of cases hinders a comprehensive understanding of potential lingering effects. Response variations to treatments like prednisone and NSAIDs, without standardized protocols, underscore the need for personalized approaches. The uncertainty surrounding the autoimmune component in COVID-19-associated SAT, despite the presence of anti-thyroid antibodies in some cases, requires further investigation. It is crucial to recognize these limitations to interpret the findings in the context of the evolving understanding of COVID-19 and SAT, emphasizing the need for ongoing research and scrutiny.

Conclusions

In conclusion, the complex interplay of clinical presentations and treatment responses underscores the formidable nature of SAT, particularly within the COVID-19 context. The consistent trend toward recovery and normalization of thyroid function not only suggests potential treatment efficacy but also emphasizes the necessity for vigilant symptom monitoring, especially in individuals with a history of COVID-19. Future studies should explore deeper into the nuanced intricacies of SAT post-COVID-19, facilitating a more refined and targeted approach to diagnosis, treatment, and patient care.

Authors’ contributions

K.G and F.S and H.S and A.S wrote the main manuscript. M.G prepared figures and tables. R.C and L.D and MJN G.BM and G.S supervised the manuscript. MJN, GBM and GS edited and revised the manuscript. All authors reviewed the manuscript.

Funding

There is no funding to report.

Data availability

All data analyzed during this study are included in the manuscript.

Declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.