Outcome of Sars-COV-2-related thyrotoxicosis in survivors of Covid-19: a prospective study

Thyroid dysfunction in COVID-19

The COVID-19 pandemic has affected over 772 million people globally. While lung damage is the major contributor to the morbidity and mortality of this disease, the involvement of multiple organs, including the endocrine glands, has been reported. This Review aims to provide an updated summary of evidence regarding COVID-19 and thyroid dysfunction, incorporating highlights of recent advances in the field, particularly in relation to long COVID and COVID-19 vaccination. Since subacute thyroiditis following COVID-19 was first reported in May 2020, thyroid dysfunction associated with COVID-19 has been increasingly recognized, secondary to direct and indirect effects on the hypothalamic-pituitary-thyroid axis. Here, we summarize the epidemiological evidence, pattern and clinical course of thyroid dysfunction following COVID-19 and examine radiological, molecular and histological evidence of thyroid involvement in SARS-CoV-2 infection. Beyond acute SARS-CoV-2 infection, it is also timely to examine the course and implication of thyroid dysfunction in the context of long COVID owing to the large population of survivors of COVID-19 worldwide. This Review also analyses the latest evidence on the relationship between the therapeutics and vaccination for COVID-19 and thyroid dysfunction. To conclude, evidence-based practice recommendations for thyroid function testing during and following COVID-19 and concerning COVID-19 vaccination are proposed.

Association between COVID-19 and sexual health: an umbrella review

PURPOSE

We conducted this umbrella review to review the current evidence on the relationship between COVID-19 and sexual health in both men and women.

METHODS

We conducted searches in Pubmed, Embase, and the Cochrane dataset for meta-analyses that met our pre-set inclusion criteria. We included studies with detailed information investigating the link between COVID-19 and sexual health in men/women. We did not limit the language.

RESULTS

The results of the included studies frequently relied on the Female Sexual Function Index to assess sexual health in women. For men, the International Index of Male Function and hospital diagnoses were commonly used to assess sexual health. Currently, there is conflicting evidence regarding the impact of COVID-19 on sexual health. However, since most studies were observational in nature, additional study designs are necessary to draw definitive conclusions across different contexts.

CONCLUSION

Our findings highlight the importance of sexual health among COVID-19 patients and people affected due to COVID-19. Further critical studies should investigate the mechanism underlying the association between COVID-19 and sexual health.

Serum testosterone mirrors inflammation parameters in females hospitalized with COVID-19

BACKGROUND

While low testosterone (T) was described as a predictor of unfavorable coronavirus-disease 19 (COVID-19) outcome in men, data concerning the role of T in women with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are scant and limited to small cohorts. This study investigated the relationship between serum T values and outcomes of COVID-19 in a large female hospitalized cohort.

METHODS

One-hundred-sixty-eight adult women (median age 77, range 18-100 years; 154 in post-menopause) hospitalized for COVID-19 were assessed for PaO2/Fio2 ratio, serum T and inflammatory parameters.

RESULTS

Median duration for hospital stay was 14.2 days (range 1-115) with overall mortality of 26% (n = 44). Subjects who died were significantly older (p < 0.001), had significantly more comorbidities (p = 0.015) and higher serum T (p = 0.040), white blood cells (p = 0.007), c-reactive protein (CRP; p < 0.001), interleukin-6 (IL-6; p < 0.001), procalcitonin (PCT; p < 0.001), lactate dehydrogenase (LDH; p = 0.001), D-dimer (p = 0.035), fibrinogen (p = 0.038) and lower serum free-triiodothyronine (FT3; p < 0.001) and luteinizing hormone (LH; p = 0.024) values. In post-menopausal women, significant associations were observed between T levels and serum CRP (rho: 0.23; p = 0.002), IL-6 (rho: 0.41; p < 0.001), LDH (rho: 0.34; p < 0.001), D-Dimer (rho: 0.21; p = 0.008), PCT (rho: 0.26; p = 0.001) and HDL cholesterol (rho:  - 0,22, p = 0.008). In multivariate regression analyses, serum T maintained the significant association with mortality after correction for age, coexistent comorbidities and serum LH and FT3, whereas it was lost after correction for inflammatory parameters.

CONCLUSION

In females, high serum T levels might be a mirror of inflammatory phenotype and worse COVID-19 course.

Long-term outcome of thyroid abnormalities in patients with severe Covid-19

OBJECTIVE

We have previously observed thyroid dysfunction, i.e. atypical thyroiditis (painless thyrotoxicosis associated with non-thyroidal illness syndrome), in patients with severe acute respiratory syndrome coronavirus 2 disease (Covid-19). This study aimed to analyse the evolution of thyroid dysfunction over time.

METHODS

One hundred eighty-three consecutive patients hospitalised for severe Covid-19 without known thyroid history were studied at hospital admission (baseline). Survivors were offered 12-month longitudinal follow-up including assessment of thyroid function, autoantibodies and ultrasound scan (US). Patients showing US focal hypoechoic areas suggestive of thyroiditis (focal hypoechogenicity) also underwent thyroid 99mTc or 123I uptake scan.

RESULTS

At baseline, after excluding from TSH analysis, 63 out of 183 (34%) Covid-19 patients commenced on steroids before hospitalisation, and 12 (10%) showed atypical thyroiditis. Follow-up of 75 patients showed normalisation of thyroid function and inflammatory markers and no increased prevalence of detectable thyroid autoantibodies. Baseline US (available in 65 patients) showed focal hypoechogenicity in 28% of patients, of whom 82% had reduced thyroid 99mTc/123I uptake. The presence of focal hypoechogenicity was associated with baseline low TSH (P = 0.034), high free-thyroxine (FT4) (P = 0.018) and high interleukin-6 (IL6) (P = 0.016). Focal hypoechogenicity persisted after 6 and 12 months in 87% and 50% patients, respectively, but reduced in size. After 9 months, thyroid 99mTc/123I uptake partially recovered from baseline (+28%) but was still reduced in 67% patients.

CONCLUSIONS

Severe Covid-19 induces mild transient thyroid dysfunction correlating with disease severity. Focal hypoechogenicity, associated with baseline high FT4, IL6 and low TSH, does not seem to be related to thyroid autoimmunity and may persist after 1 year although decreasing in size. Long-term consequences seem unlikely.

The Influence of SARS-CoV-2 Infection on the Thyroid Gland

It is important to acknowledge the impact that COVID-19 has on the thyroid gland and how the thyroid gland status before and during infection affects SARS-CoV-2 severity. To this day those dependencies are not fully understood. It is known that the virus uses angiotensin-converting enzyme-2 as the receptor for cellular entry and it can lead to multiple organ failures due to a cytokine storm. Levels of proinflammatory molecules (such as cytokines and chemokines) which are commonly elevated during infection were significantly higher in observed SARS-CoV-2-positive patients. In terms of hypothyroidism, hyperthyroidism, and autoimmune thyroid diseases, there is no proof that those dysfunctions have a direct impact on the more severe courses of COVID-19. Regarding hyper- and hypothyroidism there was no consequential dependency between the frequency of SARS-CoV-2 infection morbidity and more severe post-infectious complications. When it comes to autoimmune thyroid diseases, more evaluation has to be performed due to the unclear relation with the level of antibodies commonly checked in those illnesses and its binding with the mentioned before virus. Nonetheless, based on analyzed works we found that COVID-19 can trigger the immune system and cause its hyperactivity, sometimes leading to the new onset of autoimmune disorders. We also noticed more acute SARS-CoV-2 courses in patients with mainly reduced free triiodothyronine serum levels, which in the future, might be used as a mortality indicating factor regarding SARS-CoV-2-positive patients. Considering subacute thyroiditis (SAT), no statistically important data proving its direct correlation with COVID-19 infection has been found. Nevertheless, taking into account the fact that SAT is triggered by respiratory tract viral infections, it might be that SARS-CoV-2 can cause it too. There are many heterogenous figures in the symptoms, annual morbidity distribution, and frequency of new cases, so this topic requires further evaluation.

A prospective follow-up on thyroid function, thyroid autoimmunity and long COVID among 250 COVID-19 survivors

PURPOSE

We evaluated the evolution of thyroid function and autoimmunity among COVID-19 survivors over 6 months in relation to interferon beta-1b treatment and long COVID.

METHODS

We included COVID-19 survivors managed in a major COVID-19 centre between July 2020 and May 2021 who were reassessed three and/or six months after acute COVID-19. Thyroid function tests (TFTs) and anti-thyroid antibody titres were measured at acute COVID-19, 3-month and 6-month.

RESULTS

250 COVID-19 survivors were included (mean age 52.7 years, 50.4% men). Persistent thyroid function abnormalities were more likely in those with abnormal TFTs in acute COVID-19 (P < 0.001). Among 51 patients with abnormal TFTs in acute COVID-19, 82.4% resolved upon follow-up. Of 199 patients with normal TFTs in acute COVID-19, only 4.5% had incident abnormal TFTs, more likely in interferon-treated patients (P = 0.044) and none clinically overt. Among 129 patients with complete 6-month follow-up for anti-thyroid antibody titres, there was no significant change overall, except for modest increase in anti-thyroid antibody titres among the 84 interferon-treated patients (P < 0.05 at both 3 months and 6 months). Long COVID occurred in 19.5% and 10.4% at 3 and 6 months respectively, where TFTs and anti-thyroid antibody titres were not predictive of its occurrence.

CONCLUSION

Over 6 months, most abnormal TFTs in acute COVID-19 resolved, with no significant incident thyroid dysfunction. SARS-CoV-2 infection did not lead to change in thyroid autoimmunity, while interferon treatment was associated with modest increase in anti-thyroid antibody titres. Thyroid function and anti-thyroid antibodies did not play a significant role in long COVID.

A prospective follow-up of thyroid volume and thyroiditis features on ultrasonography among survivors of predominantly mild to moderate COVID-19

Background

We previously showed that higher SARS-CoV-2 viral load correlated with smaller thyroid volumes among COVID-19 survivors at 2 months after acute COVID-19. Our current follow-up study evaluated the evolution of thyroid volumes and thyroiditis features within the same group of patients 6 months later.

Methods

Adult COVID-19 survivors who underwent thyroid ultrasonography 2 months after infection (USG1) were recruited for follow-up USG 6 months later (USG2). The primary outcome was the change in thyroid volume. We also reassessed thyroiditis features on USG, thyroid function and anti-thyroid antibodies.

Results

Fifty-four patients were recruited (mean age 48.1 years; 63% men). The mean thyroid volume increased from USG1 to USG2 (11.9 ± 4.8 to 14.5 ± 6.2 mL, p < 0.001). Thirty-two patients (59.3%) had significant increase in thyroid volume by ≥15%, and they had a median increase of +33.3% (IQR: +20.0% to +45.0%). Multivariable logistic regression analysis showed that only higher baseline SARS-CoV-2 viral load independently correlated with significant thyroid volume increase on USG2 (p = 0.022). Among the seven patients with thyroiditis features on USG1, six (85.7%) had the features resolved on USG2. None had new thyroiditis features on USG2. All abnormal thyroid function during acute COVID-19 resolved upon USG1 and USG2.

Conclusion

Most COVID-19 survivors had an increase in thyroid volume from early convalescent phase to later convalescent phase. This increase correlated with high initial SARS-CoV-2 viral load. Together with the resolution of thyroiditis features, these may suggest a transient direct atrophic effect of SARS-CoV-2 on the thyroid gland with subsequent recovery of thyroid volume and thyroiditis features.

Thyrotropin Levels in Patients with Coronavirus Disease 2019: Assessment during Hospitalization and in the Medium Term after Discharge

BACKGROUND

The objectives of this study were (1) to compare TSH levels between inpatients with critical versus non-critical coronavirus disease 19 (COVID-19), and (2) to describe the status of TSH levels three months after hospitalization.

METHODS

We collected data on adult patients hospitalized with COVID-19 at Amiens University Hospital. We compared TSH levels between inpatients with critical (intensive care unit admission and/or death) versus non-critical COVID-19. Thereafter, survivors were invited to return for a three-month post-discharge visit where thyroid function tests were performed, regardless of the availability of TSH measurement during hospitalization.

RESULTS

Among 448 inpatients with COVID-19, TSH assay data during hospitalization were available for 139 patients without prior thyroid disease. Patients with critical and non-critical forms of COVID-19 did not differ significantly with regard to the median (interquartile range) TSH level (0.96 (0.68-1.71) vs. 1.27 mIU/L (0.75-1.79), p = 0.40). Abnormal TSH level was encountered in 17 patients (12.2%); most of them had subclinical thyroid disease. TSH assay data at the three-month post-discharge visit were available for 151 patients without prior thyroid disease. Only seven of them (4.6%) had abnormal TSH levels. Median TSH level at the post-discharge visit was significantly higher than median TSH level during hospitalization.

CONCLUSIONS

Our findings suggest that COVID-19 is associated with a transient suppression of TSH in a minority of patients regardless of the clinical form. The higher TSH levels three months after COVID-19 might suggest recovery from non-thyroidal illness syndrome.

Development of a prediction score (ThyroCOVID) for identifying abnormal thyroid function in COVID-19 patients

PURPOSE

Thyroid dysfunction in COVID-19 carries clinical and prognostic implications. In this study, we developed a prediction score (ThyroCOVID) for abnormal thyroid function (TFT) on admission amongst COVID-19 patients.

METHODS

Consecutive COVID-19 patients admitted to Queen Mary Hospital were prospectively recruited during July 2020-May 2021. Thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were measured on admission. Multivariable logistic regression analysis was performed to identify independent determinants of abnormal TFTs. ThyroCOVID was developed based on a clinical model with the lowest Akaike information criteria.

RESULTS

Five hundred and forty six COVID-19 patients were recruited (median age 50 years, 45.4% men, 72.9% mild disease on admission). 84 patients (15.4%) had abnormal TFTs on admission. Patients with abnormal TFTs were more likely to be older, have more comorbidities, symptomatic, have worse COVID-19 severity, higher SARS-CoV-2 viral loads and more adverse profile of acute-phase reactants, haematological and biochemical parameters. ThyroCOVID consisted of five parameters: symptoms (malaise), comorbidities (ischaemic heart disease/congestive heart failure) and laboratory parameters (lymphocyte count, C-reactive protein, and SARS-CoV-2 cycle threshold values). It was able to identify abnormal TFT on admission with an AUROC of 0.73 (95% CI 0.67-0.79). The optimal cut-off of 0.15 had a sensitivity of 75.0%, specificity of 65.2%, negative predictive value of 93.5% and positive predictive value of 28.1% in identifying abnormal TFTs on admission amongst COVID-19 patients.

CONCLUSION

ThyroCOVID, a prediction score to identify COVID-19 patients at risk of having abnormal TFT on admission, was developed based on a cohort of predominantly non-severe COVID-19 patients.

COVID-19 and Thyroid Function: A Bi-Directional Two-Sample Mendelian Randomization Study

Background: Thyroid dysfunction has been observed among some patients with coronavirus disease (COVID-19). It is unclear whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (or its severity) leads to the development of thyroid dysfunction, or vice versa. In this study, we examined the bi-directional causal relationship between host genetic liability to three COVID-19 phenotypes (including SARS-CoV-2 infection, hospitalized and severe COVID-19) and three thyroid dysfunction traits (including hyperthyroidism, hypothyroidism, and autoimmune thyroid disease [AITD]) and three continuous traits of thyroid hormones (including thyrotropin [TSH] and free thyroxine [fT4] within reference range, and TSH in full range). Methods: Summary statistics from the largest available meta-analyses of human genome-wide association studies were retrieved for the following variables: SARS-CoV-2 infection (n = 1,348,701), COVID-19 hospitalization (n = 1,557,411), severe COVID-19 (n = 1,059,456), hyperthyroidism (n = 51,823), hypothyroidism (n = 53,423), AITD (n = 755,406), TSH within reference range (n = 54,288), fT4 within reference range (n = 49,269), and TSH in full range (n = 119,715). Using a two-sample Mendelian randomization (MR) approach, the inverse-variance weighted (IVW) method was adopted as the main MR analysis. Weighted median, contamination mixture, MR-Egger, and MR pleiotropy residual sum and outlier (MR-PRESSO) methods were applied as sensitivity analyses. Results: Host genetic susceptibility to SARS-CoV-2 infection was causally associated with hypothyroidism in the main IVW analysis (per doubling in prevalence of SARS-CoV-2 infection, odds ratio [OR] = 1.335; 95% confidence interval [CI]: 1.167-1.526; p = 2.4 × 10^-5, surpassing the Bonferroni multiple-testing threshold). Similar causal estimates were observed in the sensitivity analyses (weighted median: OR = 1.296; CI: 1.066-1.575; p = 9 × 10^-3; contamination mixture: OR = 1.356; CI: 1.095-1.818; p = 0.013; MR-Egger: OR = 1.712; CI: 1.202-2.439; p = 2.92 × 10^-3, and MR-PRESSO: OR = 1.335; CI: 1.156-1.542; p = 5.73 × 10^-4). Host genetic liability to hospitalized or severe COVID-19 was not associated with thyroid dysfunction or thyroid hormone levels. In the reverse direction, there was no evidence to suggest that genetic predisposition to thyroid dysfunction or genetically determined thyroid hormone levels altered the risk of the COVID-19 outcomes. Conclusions: This bi-directional MR study supports that host response to SARS-CoV-2 viral infection plays a role in the causal association with increased risk of hypothyroidism. Long-term follow-up studies are needed to confirm the expected increased hypothyroidism risk.

The potential impact of COVID-19 on thyroid gland volumes among COVID-19 survivors

PURPOSE

Data about the effects of COVID-19 on the endocrine system are increasing over time. In the present study, we investigated the effects of COVID-19 on the thyroid gland among COVID-19 survivors by comparing them with healthy subjects.

METHODS

Adult COVID-19 survivors who were managed and followed up in the Infectious Disease clinic were asked to participate in this study. COVID-19 survivors were recruited via a convenience sampling and those who agreed to participate in this study were seen by endocrinologists for assessments. The blood tests were obtained for thyroid antibodies and thyroid function tests. Thyroid ultrasonography (USG) was done by the same physician. The ellipsoid formula was used for the calculation of thyroid gland volume.

RESULTS

64 adult COVID-19 survivors and 70 control subjects were enrolled in the study. The COVID-19 survivors were evaluated at median 5.7 months (IQR: 4-6.5) (range: 2-7 months) after acute infection. The mean thyroid gland volume was significantly lower in COVID-19 survivors (10.3 ± 3.4 mL) than in the controls (14 ± 5.3 mL) (p = 0.001). There was no significant difference in free triiodothyronine (fT3), free thyroxine (fT4) and thyroid-stimulating hormone (TSH) levels between the groups. Among the twelve patients who had thyroid function evaluated in acute COVID-19, fT3 values were lower in acute COVID-19 than at the time of USG evaluation (3.04 ± 0.41 vs 3.47 ± 0.31 pg/mL), (p = 0.02). Among COVID-19 survivors, mild TSH elevation was detected in 4 (6.2%) patients and all of the other COVID-19 survivors (93.7%) were euthyroid.

CONCLUSIONS

At 6 months after acute COVID, COVID-19 survivors had smaller thyroid gland volume than healthy controls, and only a few of the COVID-19 survivors had abnormal thyroid function.

Low testosterone predicts hypoxemic respiratory insufficiency and mortality in patients with COVID-19 disease: another piece in the COVID puzzle

PURPOSE

Hypogonadism was described in high number of male subjects with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In this study, we investigated whether low testosterone (T) values may influence the clinical presentation and outcome of SARS-CoV-2-related pneumonia in a large population of adult males with coronavirus disease 19 (COVID-19).

METHODS

Two hundred twenty one adult males hospitalized for COVID-19 at the IRCCS Humanitas Research Hospital, Rozzano-Milan (Italy) were consecutively evaluated for arterial partial pressure oxygen (PaO₂)/fraction of inspired oxygen (FiO₂) ratio, serum T and inflammatory parameters at study entry, need of ventilation during hospital stay and in-hospital mortality.

RESULTS

Subjects low T values (< 8 nmol/L; 176 cases) were significantly older (P = 0.001) and had higher serum interleukin-6 (P = 0.001), C-reactive protein (P < 0.001), lactate dehydrogenase (P < 0.001), ferritin (P = 0.012), lower P/F ratio (P = 0.001), increased prevalence of low T3 syndrome (P = 0.041), acute respiratory insufficiency (P < 0.001), more frequently need of ventilation (P < 0.001) and higher mortality rate (P = 0.009) compared to subjects with higher T values. In the multivariable regression analyses, T values maintained significant associations with acute respiratory insufficiency (odds ratio [OR] 0.85, 95% confidence interval [CI] 0.79-0.94; P < 0.001 and in-hospital mortality (OR 0.80, 95% CI 0.69-0.95; P = 0.009), independently of age, comorbidities, thyroid function and inflammation.

CONCLUSION

Low T levels values are associated with unfavorable outcome of COVID-19. Prospective studies are needed to evaluate the long-term outcomes of hypogonadism related to COVID-19 and the clinical impact of T replacement during and after acute illness.

Post-COVID-19 Condition: Where Are We Now?

COVID-19 is currently considered a systemic infection involving multiple systems and causing chronic complications. Compared to other post-viral fatigue syndromes, these complications are wider and more intense. The most frequent symptoms are profound fatigue, dyspnea, sleep difficulties, anxiety or depression, reduced lung capacity, memory/cognitive impairment, and hyposmia/anosmia. Risk factors for this condition are severity of illness, more than five symptoms in the first week of the disease, female sex, older age, the presence of comorbidities, and a weak anti-SARS-CoV-2 antibody response. Different lines of research have attempted to explain these protracted symptoms; chronic persistent inflammation, autonomic nervous system disruption, hypometabolism, and autoimmunity may play a role. Due to thyroid high ACE expression, the key molecular complex SARS-CoV-2 uses to infect the host cells, thyroid may be a target for the coronavirus infection. Thyroid dysfunction after SARS-CoV-2 infection may be a combination of numerous mechanisms, and its role in long-COVID manifestations is not yet established. The proposed mechanisms are a direct effect of SARS-CoV-2 on target cells, an indirect effect of systemic inflammatory immune response, and a dysfunction of the hypothalamic-pituitary-thyroid (HPT) axis leading to decreased serum TSH. Only a few studies have reported the thyroid gland status in the post-COVID-19 condition. The presence of post-COVID symptoms deserves recognition of COVID-19 as a cause of post-viral fatigue syndrome. It is important to recognize the affected individuals at an early stage so we can offer them the most adequate treatments, helping them thrive through the uncertainty of their condition.

The Sexual Long COVID (SLC): Erectile Dysfunction as a Biomarker of Systemic Complications for COVID-19 Long Haulers

Introduction

Long term complications of COVID-19, the disease caused by the SARS-CoV-2, involve many organ systems, dramatically worsening the quality of life, and finally contributing to impaired physical functioning. Despite the presence of well-identified pathogenetic mechanisms, the effect of “Long COVID” on sexual health has been only marginally addressed.

Objectives

To provide coverage of the current literature on long COVID, its epidemiology, pathophysiology, and relevance for erectile function. Methods. Comprehensive review of literature pertaining to the epidemiology and pathophysiology of long COVID, and its relevance for erectile function.

Results

Symptoms of long COVID are highly prevalent and involve almost all systems of the human body, with a plethora of clinical manifestations which range from minor nuisances to life-threatening conditions. “Brain fog” and fatigue are the most common complaints, although other neuropsychiatric complications, including sensory dysfunctions, anxiety, depression, and cerebrovascular events have also been reported. The respiratory and cardiovascular systems are also affected, with dyspnea, pulmonary fibrosis, endothelial dysfunction, and myocarditis occurring in some COVID long haulers. A subset of patients might develop endocrine manifestations, including onset of diabetes, thyroid dysfunction, and hypogonadism. Overall, long COVID features many complications which can impair erectile function by multiple pathogenetic mechanisms, and which could require tailored treatment: (i) careful investigation and management from the sexual medicine expert are therefore much needed, (ii) and future research on this topic is warranted.

Conclusion

in COVID-19 long haulers, several complications can adversely affect erectile function which, upon future tailored studies, could be used as biomarker for the severity of the long COVID disease and for its follow-up.

Sansone A, Mollaioli D, Limoncin E et al. The Sexual Long COVID (SLC): Erectile Dysfunction as a Biomarker of Systemic Complications for COVID-19 Long Haulers. Sex Med Rev 2022;10:271–285.

Higher SARS-CoV-2 viral loads correlated with smaller thyroid volumes on ultrasound among male COVID-19 survivors

PURPOSE

Thyroid dysfunction, including thyroiditis, is well recognized in COVID-19 patients. We evaluated thyroid ultrasonographic features among COVID-19 survivors, which are less well known.

METHODS

Adult COVID-19 survivors without known thyroid disorders who attended dedicated COVID-19 clinic underwent thyroid ultrasonography and assessment of thyroid function and autoimmunity. Adults admitted for acute non-thyroidal surgical problems and negative for COVID-19 were recruited as control. SARS-CoV-2 viral load (VL) was presented as the inverse of cycle threshold values from the real-time reverse transcription-polymerase chain reaction of the respiratory specimen on admission.

RESULTS

In total, 79 COVID-19 patients and 44 non-COVID-19 controls were included. All abnormal thyroid function tests during acute COVID-19 recovered upon follow-up. Thyroid ultrasonography was performed at a median of 67 days after acute COVID-19. The median thyroid volume was 9.73 mL (IQR: 7.87-13.70). In multivariable linear regression, SARS-CoV-2 VL on presentation (standardized beta -0.206, p = 0.042) inversely correlated with thyroid volume, in addition to body mass index at the time of ultrasonography (p < 0.001). Sex-specific analysis revealed similar results among men but not women. Eleven COVID-19 patients (13.9%) had ultrasonographic changes suggestive of thyroiditis, comparable to non-COVID-19 patients (p = 0.375). None of these 11 patients had isolated low thyroid-stimulating hormone levels suggestive of thyroiditis at initial admission or the time of ultrasonography.

CONCLUSIONS

Higher SARS-CoV-2 VL on presentation were associated with smaller thyroid volumes, especially in men. Further research is suggested to investigate this possible direct viral effect of SARS-CoV-2 on the thyroid gland. There was no increased rate of ultrasonographic features suggestive of thyroiditis in COVID-19 survivors.