Thyroid axis and COVID 19

Introduction: Non-thyroidal illness syndrome (NTIS) is also known as low T3 syndrome. NTIS is characterized by low plasma T3, low or normal T4, or elevated reverse T3 (rT3), with normal or slightly decreased TSH. NTIS is a strong predictor of poor prognosis in critically ill hospitalized patients. Different thyroid hormone profiles were defined during critical illness. High fT4 with a low fT3 level in patients with coronary heart disease were significantly related to mortality. If NTIS is a physiologic response to a systemic inflammation or a maladaptation status is controversial. NTIS with low fT3 and a lower fT3/fT4 ratio was referred in patients with COVID-19. Furthermore, angiotensin-converting enzyme (ACE) 2, an receptor in the pathogenesis of COVID-19, was demonstrated to be expressed in the thyroid gland. SARS-CoV-2- related thyroiditis is recognized. The effects of COVID-19 on the thyroid axis remain uncertain. Objectives: We aimed to study the characteristics of thyroid hormone levels in inpatients with COVID-19. Methods: Prospective study: 57 covid-19 patients (29/57 ♂) with criteria for admission to a medical clinic from August to November 2020. Median age was 56 years (range(R) : 21-89). 3,6% was asymptomatic, 14,3% mild, 28,6% moderate and 53,6% severe. fT4, TT3, TSH, TgAb and TPOAb were analysed in addition to studies due to their underlying pathology. Data are expressed as median and R or mean ± SD and % Results: The median of TSH was 1.77 uUI/ml (R: 0.02-64.9), the X ± SD of fT4 and TT3 was 1.22 ± 0.3 ng/ml and 72.3 ± 23.04 ng/dl respectively. Forty two/ 57 patients presented low T3. The profiles observed in this group are described in table 1. Two patients with positive TPOAb had high TSH, low T3 and normal fT4 and 3 only low T3. Image: Conclusion: 1-In this population of COVID-19 patients upon admission to hospitalization and excluding one clinical hypothyroid patient 73, 7% presented low T3. 2- In the patient with clinical hypothyroidism and negative antibodies as well as those with altered TSH, low TT3 and normal or high fT4 we cannot exclude destructive or autoinmune thyroiditis until the evolution is known. 3-Classic NTI with low T3, low o normal fT4 and nomal TSH was observed in 42, 1% patients. 4- It should be noted the high prevalence of patients with low TT3, high fT4 and normal TSH. We consider that is another face of NTI in COVID-19 as it was referred in patients with coronary disease.To our knowledge, this is the first descriptive report of different faces of NTI in COVID 19 patients.

Hyperthyroidism in outpatients during the COVID 19 pandemic. experience of a referral center in the city of buenos aires

Introduction: Different changes in thyroid function have been described in Covid 19 + patients, including subacute postinfection thyroiditis and reactivation of autoimmune hyperthyroidism. Although attention has been focused on the viral infection, the stressful situation arising from the pandemic and especially quarantine, should be considered as another determinant of thyroid changes. This should also affect non- Covid population. OBJECTIVES1) To evaluate new cases of hyperthyroidism diagnosed in non-Covid outpatient from an endocrinology referral center in the City of Buenos Aires during the pandemic 2) Determine its etiology, severity.3) To compare it with cases diagnosed in the same period of the previous year. Case Description: MATERIAL and METHODS There were 435 Total T3 determinations reviewed, between the start of Covid quarantine in Argentina 03/20/2020 and 11/20/2020. The results above the upper reference limit (175 ng/dl) were analyzed. It was possible to establish the number of patients with clinical hyperthyroidism diagnosis who made their first consultation during this period. Thyroid status was confirmed with Total T4 and TSH determinations.The number of cases was established in the same period of the previous year, using the same system. Aetiology was established with clinic, evolution and TSI/TRAb Total T3, total T4, TSH and TSI, were measured by the IMMULITE 2000 XPi enzyme-linked chemoimmunoassay, Siemens.Trab was measured by Cobas e411 electrochemiluminescent assay,Roche Statistics Student T Test- Fischer Test (Table Presented) Conclusions 1) During the pandemic, 15 new cases of hyperthyroidism were diagnosed. Such figure represents half the number of cases in comparison with the previous year. 2) Autoimmune etiology prevalence was similar. 3) No lesional thyroiditis was detected in those outpatients, clinically non-Covid evaluated from elevated T3. 4) Total T3 was significantly higher in 2020, reflecting that only the most severe hyperthyroidism cases attended consultation.

Correlation between inflammatory parameters and thyroid hormones in patients with COVID-19

Introduction: Non-thyroidal illness syndrome (NTI), (decreased T3 and/or T4 without increased TSH), has been reported in COVID-19 infection. In patients admitted with COVID-19 we found classic NTI presentation and a high prevalence of low T3, high freeT4 (FT4) and normal TSH, which could represent a different presentation of NTI. Low T3 and high FT4 have been associated with mortality1. Objectives: 1-To evaluate correlation of thyroid hormones with biochemical markers of inflammation and association with disease outcome in hospitalized patients with COVID-19. 2-To evaluate these parameters in the two profiles of NTI. Methods: Prospective single- center study that included 55 consecutively patients with COVID-19 hospitalized from August to November 2020. 28/55 (50 %) were male, median age 56y (21-89). Clinical presentation: asymptomatic 3,6% (n=2), mild 14,3% (n=8), moderate 28,6% (n=16), severe 53,6% (n=30). 74,1% had pneumonia, 3.6% (n=2) died and 79,3% had favorable evolution. Thyroid hormones (T4, T3, FT4, FT3) and their ratios (T3/T4, FT3/FT4) were correlated with inflammatory parameters (albumin, ferritin, fibrinogen, erythrocyte sedimentation rate [ESR], C-reactive protein [CRP], lactate dehydrogenase [LDH], D-dimer). Comparison between hormone levels, clinical presentation and outcome was performed. Statistical analysis: Spearman correlation, Mann Whitney test and Kruskal-Wallis test. Results: We found correlation between thyroid hormones and their ratios with inflammatory parameters (Table). T3/T4 ratio was lower in severe vs mild/moderate disease [7.5 (4.5-15.5) vs 9.2 (5.8-18.1);p=0.04] and in patients who died vs those discharged [5 (4.53-5.6) vs 8.1 (4.7-18.1);p=0.03]. High FT4 NTI had lower albumin [3.4 (3-4) vs 3.7 (3-4);p=0.03], higher ferritin [1202 (930-7127) vs 435 (101-2232);p<0.05] and tendency to higher fibrinogen [681(583-798) vs 508 (307- 807);p=0.06] than normal/low FT4 NTI. No patient with mild disease at onset had high FT4. Image: Conclusion: In this cohort, both thyroid hormones correlated with inflammation parameters and worse clinical outcome. In NTI group with high FT4, inflammatory parameters were more marked and presentation of the disease more severe.