Enzymatic Precipitation of Highly Electroactive and Ion-Transporting Prussian Blue for a Sensitive Electrochemical Immunosensor.

Sensitive and/or multiplex electrochemical biosensors often require efficient (bio)catalytic conversion of substrates into insoluble electroactive products. The enzymatic formation and precipitation of coordination polymers under mild conditions offers a promising solution for this purpose. Herein, we report the enzymatic precipitation of Prussian blue (PB), a highly electroactive and ion-transporting coordination polymer, on an immunosensing electrode for application in a sensitive electrochemical immunosensor for detecting thyroid-stimulating hormone (TSH). Five pairs of redox enzymes and their specific reductants were examined to achieve rapid PB precipitation and electrochemical oxidation. Among these pairs, O2-insensitive flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH) paired with glucose yielded the highest electrochemical signal-to-background (S/B) ratio. FAD-GDH catalyzed the conversion of Fe(CN)63- to Fe(CN)64-, which coordinated with Fe3+, leading to PB formation and subsequent precipitation through repeated conversions. The resulting PB precipitate, with its close proximity to the electrode, facilitated rapid electrochemical oxidation and generated a strong electrochemical signal. Notably, the precipitation and electrochemical oxidation of PB were more effective than those of its analogues. When applied to a sandwich-type immunosensor for TSH detection, the enzymatic PB precipitation achieved a calculated detection limit of approximately 2 pg/mL in artificial serum, covering the clinically relevant range. These findings indicate the potential widespread utility of PB precipitation and electrochemical oxidation for sensitive multiplex biomarker detection.

Should we depend on reference intervals from manufacturer package inserts? Comparing TSH and FT4 reference intervals from four manufacturers with results from modern indirect methods and the direct method.

OBJECTIVES: Correct interpretation of thyroid function tests relies on correct reference intervals (RIs) for thyroid-stimulating hormone (TSH) and free thyroxine (FT4). ISO15189 mandates periodic verification of RIs, but laboratories struggle with cost-effective approaches. We investigated whether indirect methods (utilizing historical laboratory data) could replace the direct approach (utilizing healthy reference individuals) and compared results with manufacturer-provided RIs for TSH and FT4. METHODS: We collected historical data (2008-2022) from 13 Dutch laboratories to re-establish RIs by employing indirect methods, TMC (for TSH) and refineR (for FT4). Laboratories used common automated platforms (Roche, Abbott, Beckman or Siemens). Indirect RIs (IRIs) were determined per laboratory per year and clustered per manufacturer (>1.000.000 data points per manufacturer). Direct RIs (DRIs) were established in 125 healthy individuals per platform. RESULTS: TSH IRIs remained robust over the years for all manufacturers. FT4 IRIs proved robust for three manufacturers (Roche, Beckman and Siemens), but the IRI upper reference limit (URL) of Abbott showed a decrease of 2 pmol/L from 2015. Comparison of the IRIs and DRIs for TSH and FT4 showed close agreement using adequate age-stratification. Manufacturer-provided RIs, notably Abbott, Roche and Beckman exhibited inappropriate URLs (overall difference of 0.5-1.0 µIU/mL) for TSH. For FT4, the URLs provided by Roche, Abbott and Siemens were overestimated by 1.5-3.5 pmol/L. CONCLUSIONS: These results underscore the importance of RI verification as manufacturer-provided RIs are often incorrect and RIs may not be robust. Indirect methods offer cost-effective alternatives for laboratory-specific or platform-specific verification of RIs.

A National Laboratory Perspective: The Impact of the Covid-19 Pandemic on the Management of Patients With Non-Communicable Disease in South Africa: Impact of COVID-19 on patients with noncommunicable diseases.

OBJECTIVE: The aim of this study was to determine the impact of the COVID-19 pandemic on test requests for the diagnosis and routine care of patients with various non-communicable diseases (NCD) across South Africa (SA). METHODS: A retrospective audit of laboratory test requests received from hospital outpatient departments and primary healthcare facilities across SA was performed. The following analytes were studied: glycated hemoglobin (HbA1c), lipids profiles, thyroid-stimulating hormone (TSH), and thyroxine (fT4), as well as triiodothyronine (fT3), serum protein electrophoresis (SPE), serum free light chains (SFLC), and prostate specific antigen (PSA); these tests were used as a proxy of NCD detection and follow-up. Requests received during the 3 waves of the pandemic were compared to requests received within the same period during 2017 - 2019. RESULTS: During the first wave, requests for all analytes were reduced, with the biggest reduction observed for SPE (- 37%); TSH (- 29%); fT4 (- 28%); and HbA1c (- 25%). Requests received from urban facilities showed a larger decrease compared to those from rural facilities. During the third wave there was an increase in requests for all analytes; the biggest increase observed was for fT3 (21%) and HbA1c (18%). CONCLUSIONS: The COVID-19 pandemic had a significant impact on the South African population receiving care in the public healthcare sector.

Hyperthyroidism: A Review.

Importance: Overt hyperthyroidism, defined as suppressed thyrotropin (previously thyroid-stimulating hormone) and high concentration of triiodothyronine (T3) and/or free thyroxine (FT4), affects approximately 0.2% to 1.4% of people worldwide. Subclinical hyperthyroidism, defined as low concentrations of thyrotropin and normal concentrations of T3 and FT4, affects approximately 0.7% to 1.4% of people worldwide. Untreated hyperthyroidism can cause cardiac arrhythmias, heart failure, osteoporosis, and adverse pregnancy outcomes. It may lead to unintentional weight loss and is associated with increased mortality. Observations: The most common cause of hyperthyroidism is Graves disease, with a global prevalence of 2% in women and 0.5% in men. Other causes of hyperthyroidism and thyrotoxicosis include toxic nodules and the thyrotoxic phase of thyroiditis. Common symptoms of thyrotoxicosis include anxiety, insomnia, palpitations, unintentional weight loss, diarrhea, and heat intolerance. Patients with Graves disease may have a diffusely enlarged thyroid gland, stare, or exophthalmos on examination. Patients with toxic nodules (ie, in which thyroid nodules develop autonomous function) may have symptoms from local compression of structures in the neck by the thyroid gland, such as dysphagia, orthopnea, or voice changes. Etiology can typically be established based on clinical presentation, thyroid function tests, and thyrotropin-receptor antibody status. Thyroid scintigraphy is recommended if thyroid nodules are present or the etiology is unclear. Thyrotoxicosis from thyroiditis may be observed if symptomatic or treated with supportive care. Treatment options for overt hyperthyroidism from autonomous thyroid nodules or Graves disease include antithyroid drugs, radioactive iodine ablation, and surgery. Treatment for subclinical hyperthyroidism is recommended for patients at highest risk of osteoporosis and cardiovascular disease, such as those older than 65 years or with persistent serum thyrotropin level less than 0.1 mIU/L. Conclusions and Relevance: Hyperthyroidism affects 2.5% of adults worldwide and is associated with osteoporosis, heart disease, and increased mortality. First-line treatments are antithyroid drugs, thyroid surgery, and radioactive iodine treatment. Treatment choices should be individualized and patient centered.

Control of Thyroid Dysfunction in Spanish Population Registered in the Primary Care Clinical Database: An Analysis of the Proportion of Patients with Thyrotropin Values Outside the Reference Range.

Inadequate control of thyroid dysfunction is common and has deleterious health consequences. Our objective was to determine the prevalence of TSH values outside the reference range, as an indicator of inadequate control of hypothyroidism and hyperthyroidism in patients undergoing treatment for thyroid dysfunction in Spain. An observational, retrospective, non-interventional study was conducted using the Primary Care Clinical Database (BDCAP). Patients treated with thyroid hormone for hypothyroidism and with antithyroid drugs for hyperthyroidism were identified. We assessed serum TSH concentration, considering values from 0.4 to 4.0 mU/l as the reference interval. We found 360 313 people with hypothyroidism on thyroid hormone replacement and 9239 with hyperthyroidism on antithyroid drugs therapy. TSH values outside the reference range in hypothyroid subject were detected in 126 866 (35.20%) people, of whom 107 205 (29.75%) had TSH>4.0 mU/l, suggesting inappropriately low doses of levothyroxine, and 19 661 (5.46%) had TSH<0.4 mU/l, suggesting inappropriate over replacement. In the hyperthyroid group, TSH values outside the reference range were observed in 4252 (46.02%) patients. There were 2833 (30.66%) patients with TSH<0.4 mU/l, suggesting undertreatment, and 1419 (15.36%) with TSH>4.0 mU/l, suggesting overtreatment with antithyroid medication. People over 65 years of age had a lower frequency of undertreatment of hypothyroidism and a lower frequency of overtreatment and undertreatment of hyperthyroidism. In conclusion, our results suggest that inadequate control of thyroid dysfunction, due to its high frequency and its consequences for health, is a public health problem that should be addressed by clinicians and health authorities.

Approach to Subclinical Hypothyroidism in Adults / Abordaje del Hipotiroidismo subclínico en el Adulto

Thyroid pathology is the morphofunctional evolution of the thyroid glands that leads to different types of clinical pictures. Within it is subclinical hypothyroidism, which is a biochemical alteration due to the elevation of thyroid-stimulating hormone (TSH) between 4.5 to 10 mUI that can occur with or without symptoms of multifactorial origin. The worldwide prevalence is 4-10% and Latin America 15-25%. 90% of patients with this pathology do not require treatment, but in turn there is an overmedicalization and underdiagnosis of it. This bibliographic review analyzes from its morphofunctional changes towards clinical criteria for a comprehensive approach to subclinical hypothyroidism, where we have an individualization by its comorbidities, age group, diagnostic algorithm, follow-up and differentiated treatment according to recent studies within this pathology. Therefore, an adequate diagnosis, follow-up and treatment provides a better lifestyle for patients.

La patología tiroidea es la alteración morfofuncional de la glándula tiroides que lleva a diferentes tipos de cuadros clínicos. Dentro de ella se encuentra el Hipotiroidismo subclínico que es una alteración bioquímica por la elevación de la Hormona Estimulante de la tiroides (TSH) entre 4,5 a 10 mUI que puede presentarse con o sin sintomatología y tiene etiología multifactorial. La prevalencia mundial es del 4-10 % y latinoamericana del 15-25%. El 90% de pacientes con esta patología no requieren tratamiento, pero a su vez existe una sobremedicalización y una subdiagnóstico del mismo. La presente revisión bibliografía analiza a partir de su alteración morfofuncional hacia criterios clínicos para un abordaje integral del Hipotiroidismo subclínico, donde tenemos una individualización por sus comorbilidades, grupo etario, algoritmo diagnóstico, seguimiento y tratamiento diferenciado según últimos estudios dentro de esta patología. Por lo que un adecuado diagnóstico, seguimiento y tratamiento brinda un mejor estilo de vida a los pacientes.

First Estimation of Reference Intervals for Thyroid-Stimulating Hormone and Thyroid Hormones in Slovenian Population.

For thyroid function estimation and clinical decision making, use of appropriate reference intervals for thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) is crucial. For each laboratory, establishment of own reference intervals is advised. For the first Slovenian estimation of reference intervals for thyroid hormones a large group of 1722 healthy individuals without thyroid disease was established retrospectively. Hormone analyses were performed on automated analyser Advia Centaur XP Immunoassay System (Siemens Healthineers), which reference intervals for TSH, fT4 and fT3 were 0.55-4.78 mIU/L, 11.5-22.7 pmol/L, and 3.5-6.5 pmol/L, respectively. Statistical analysis followed non-parametric percentile method. Our laboratory reference intervals for TSH, fT4 and fT3 are mostly narrower than intervals given by manufacturer. Median value, lower and upper limit for TSH, fT4 and fT3 were 1.98 (0.59-4.23) mIU/L, 14.5 (11.3-18.8) pmol/L and 4.82 (3.79-6.05) pmol/L, respectively. Most likely, an inclusion of a high number of healthy individuals without thyroid disease was a reason for such results.

[Graves' Disease]. / Morbus Basedow.

DIAGNOSIS: The diagnosis of Graves' disease is mainly based on ultrasonography and laboratory diagnostics. This includes the determination of the TSH value and the peripheral thyroid hormones. TSH receptor antibody (TRAb) measurement is highly sensitive and specific for the detection of Graves' disease (GD) and helps to distinguish from autoimmune thyroiditis (AIT). However, as recent studies show, some may AIT patients may also reveal TRAb. THERAPY: Current guidelines recommend primarily the use of thiamazol/carbimazole in GD. Due to the comparatively higher hepatotoxicity, propylthiouracil is not recommended as first line therapy. In case of relapse during 12 up to 18 months of antithyroid drug therapy or after a frustrating attempt at cessation, definitive therapy should be considered. Alternatively, in accordance with the current recommendations of the European Thyroid Association, drug therapy may be continued for up to 12 months after initial diagnosis. PREGNANCY: The treatment of active GD during pregnancy is problematic due to diaplacental crossing of peripheral thyroid hormones, TSH receptor stimulating antibodies and antithyroid drugs. According to current guidelines, PTU is recommended during the first 16 weeks of pregnancy, whereas for the 2nd and 3 rd trimester no special recommendations are given. After that, you can choose which antithyroid drug might be used. The aim of antithyroid drug therapy during pregnancy is to achieve a suppressed TSH value together with normal or slightly increased fT4 while using lowest effective dose of antithyroid drug. IMMUNE CHECKPOINT INHIBITORS (ICI): The most common endocrine side effect with this therapy is thyroid dysfunction. Hyperthyroidism; occur most frequently in combination therapy (CTLA-4 / anti-PD-1 therapy) ICI mainly causes destructive thyroiditis with lymphocytic infiltration; GD is absolutely rare in this context and only few cases are described.

Association of Thyroid Dysfunction With Cognitive Function: An Individual Participant Data Analysis.

Importance: In clinical guidelines, overt and subclinical thyroid dysfunction are mentioned as causal and treatable factors for cognitive decline. However, the scientific literature on these associations shows inconsistent findings. Objective: To assess cross-sectional and longitudinal associations of baseline thyroid dysfunction with cognitive function and dementia. Design, Setting, and Participants: This multicohort individual participant data analysis assessed 114 267 person-years (median, 1.7-11.3 years) of follow-up for cognitive function and 525 222 person-years (median, 3.8-15.3 years) for dementia between 1989 and 2017. Analyses on cognitive function included 21 cohorts comprising 38 144 participants. Analyses on dementia included eight cohorts with a total of 2033 cases with dementia and 44 573 controls. Data analysis was performed from December 2016 to January 2021. Exposures: Thyroid function was classified as overt hyperthyroidism, subclinical hyperthyroidism, euthyroidism, subclinical hypothyroidism, and overt hypothyroidism based on uniform thyrotropin cutoff values and study-specific free thyroxine values. Main Outcomes and Measures: The primary outcome was global cognitive function, mostly measured using the Mini-Mental State Examination. Executive function, memory, and dementia were secondary outcomes. Analyses were first performed at study level using multivariable linear regression and multivariable Cox regression, respectively. The studies were combined with restricted maximum likelihood meta-analysis. To overcome the use of different scales, results were transformed to standardized mean differences. For incident dementia, hazard ratios were calculated. Results: Among 74 565 total participants, 66 567 (89.3%) participants had normal thyroid function, 577 (0.8%) had overt hyperthyroidism, 2557 (3.4%) had subclinical hyperthyroidism, 4167 (5.6%) had subclinical hypothyroidism, and 697 (0.9%) had overt hypothyroidism. The study-specific median age at baseline varied from 57 to 93 years; 42 847 (57.5%) participants were women. Thyroid dysfunction was not associated with global cognitive function; the largest differences were observed between overt hypothyroidism and euthyroidism-cross-sectionally (-0.06 standardized mean difference in score; 95% CI, -0.20 to 0.08; P = .40) and longitudinally (0.11 standardized mean difference higher decline per year; 95% CI, -0.01 to 0.23; P = .09). No consistent associations were observed between thyroid dysfunction and executive function, memory, or risk of dementia. Conclusions and Relevance: In this individual participant data analysis of more than 74 000 adults, subclinical hypothyroidism and hyperthyroidism were not associated with cognitive function, cognitive decline, or incident dementia. No rigorous conclusions can be drawn regarding the role of overt thyroid dysfunction in risk of dementia. These findings do not support the practice of screening for subclinical thyroid dysfunction in the context of cognitive decline in older adults as recommended in current guidelines.

Associations between the thyroid panel and serum protein concentrations across pregnancy.

Establishing any characteristic associations between the serum parameters of thyroid function and serum proteins in pregnancy may aid in elucidating the role of the thyroid gland in the regulation of pregnancy-specific metabolic processes and in selecting candidate biomarkers for use in their clinical assessment. Concentrations of thyroid stimulating hormone (TSH), free tri-iodothyronine (fT3) and free thyroxine (fT4), six electrophoretically separated protein fractions (albumin, alpha-1-, alpha2-, beta-1-, beta-2- and gamma-globulins), representative proteins-albumin (ALB), transferrin (TRF), alpha-2-macroglobulin (AMG) and ceruloplasmin (CER) were measured in 136 serum samples from 65 women in their consecutive trimesters of pregnancy. The concentrations of TSH, fT4 and fT3 were significantly correlated (p < 0.05) with the concentrations of the albumin, alpha-2- and beta-1 globulin fractions. Significant correlations (p < 0.05) which were positive between fT4 and ALB and negative between fT4 and TRF were established throughout pregnancy. Significant negative correlations (p < 0.05) were demonstrated for fT3 with alpha-2-globulin, AMG and CER. Changes in the serum concentrations of thyroid hormones seen between the trimesters were found to correlate with the concentrations of high-abundance serum proteins. Opposite directions of correlations between fT4 and ALB and fT4 and TRF observed throughout pregnancy may indicate the shared biological role of these parameters in maintaining maternal homeostasis and they suggest their potential use in the clinic as a simple biomarker panel. A negative correlation of fT3 with CER in the second trimester possibly reflects their involvement in the active regulation of metabolic processes.

Biotin Interference in Assays for Thyroid Hormones, Thyrotropin and Thyroglobulin.

Background: Biotin has been reported to interfere with several commonly used laboratory assays resulting in misleading values and possible erroneous diagnosis and treatment. This report describes a prospective study of possible biotin interference in thyroid-related laboratory assays, with a comparison of different commonly used assay platforms. Materials and Methods: Thirteen adult subjects (mean age 45 ± 13 years old) were administered biotin 10 mg/day for eight days. Blood specimens were collected at three time points on day 1 and on day 8 (baseline, two, and five hours after biotin ingestion). Thyrotropin (TSH), free triiodothyronine (fT3), free thyroxine (fT4), total triiodothyronine (TT3), total thyroxine (TT4), thyroxine binding globulin (TBG), and thyroglobulin (Tg) levels were analyzed with four different platforms: Abbott Architect, Roche Cobas 6000, Siemens IMMULITE 2000, and liquid chromatography with tandem mass spectrometry (LC-MS/MS). TSH, fT3, fT4, TT3, and TT4 were measured with Abbott Architect and Roche Cobas 6000. fT3, fT4, TT3, and TT4 were also measured by LC-MS/MS. Tg was measured by Siemens IMMULITE 2000. TBG was assessed with Siemens IMMULITE 2000. Results: Significant changes in TSH, fT4, and TT3 measurements were observed after biotin exposure when the Roche Cobas 6000 platform was used. Biotin intake resulted in a falsely lower Tg level when measurements were performed with Siemens IMMULITE 2000. At the time points examined, maximal biotin interference was observed two hours after biotin exposure both on day 1 and day 8. Conclusions: A daily dose of 10 mg was shown to interfere with specific assays for TSH, fT4, TT3, and Tg. Physicians must be aware of the potential risk of erroneous test results in subjects taking biotin supplements. Altered test results for TSH and Tg can be particularly problematic in patients requiring careful titration of levothyroxine therapy such as those with thyroid cancer.

Does Subclinical Hypothyroidism Add Any Symptoms? Evidence from a Danish Population-Based Study.

BACKGROUND: Few studies have scrutinized the spectrum of symptoms in subclinical hypothyroidism. METHODS: From 3 Danish Investigation on Iodine Intake and Thyroid Diseases (DanThyr) cross-sectional surveys performed in the period 1997 to 2005, a total of 8903 subjects participated in a comprehensive investigation including blood samples and questionnaires on previous diseases, smoking habits, alcohol intake, and education. From the 3 surveys we included patients with subclinical hypothyroidism (n = 376) and euthyroid controls (n = 7619). We explored to what extent patients with subclinical hypothyroidism reported 13 previously identified hypothyroidism-associated symptoms (tiredness, dry skin, mood lability, constipation, palpitations, restlessness, shortness of breath, wheezing, globus sensation, difficulty swallowing, hair loss, dizziness/vertigo, and anterior neck pain). In various uni- and multivariate regression models we searched for circumstances predicting why some patients have more complaints than others. RESULTS: Subclinically hypothyroid patients did not report higher hypothyroidism score [(median, interquartile range), 2 (0-4) vs 2 (0-4), P = .25] compared with euthyroid controls. Within the group of subclinical hypothyroid patients, comorbidity had the highest impact on symptoms (tiredness, shortness of breath, wheezing; all P < .001); TSH level had no impact on symptom score; and younger age was accompanied by higher mental burden (tiredness, P < .001; mood lability, P < .001; restlessness, P = .012), whereas shortness of breath was associated with high body mass index (P < .001) and smoking (P = .007). CONCLUSION: Patients with a thyroid function test suggesting subclinical hypothyroidism do not experience thyroid disease-related symptoms more often than euthyroid subjects. In subclinical hypothyroidism, clinicians should focus on concomitant diseases rather than expecting symptomatic relief following levothyroxine substitution.

Transcription factor immunohistochemistry in the diagnosis of pituitary tumours.

OBJECTIVE: The clinical utility and prognostic value of WHO 2017 lineage-based classification of pituitary tumours have not been assessed. This study aimed to (1) determine the clinical utility of transcription factor analysis for classification of pituitary tumours and (2) determine the prognostic value of improved lineage-based classification of pituitary tumours. METHODS: This was a retrospective evaluation of patients who underwent surgical resection of pituitary tumours at St Vincent's Public and Private Hospitals, Sydney, Australia between 1990 and 2016. Included patients were at least 18 years of age and had complete histopathological data, forming the 'histological cohort'. Patients with at least 12 months of post-surgical follow-up were included in the subgroup 'clinical cohort'. The diagnostic efficacy of transcription factor immunohistochemistry in conjunction with hormone immunohistochemistry was compared with hormone immunohistochemistry alone. The prognostic value of identifying 'higher-risk' histological subtypes was assessed. RESULTS: There were 171 patient tumour samples analyzed in the histological cohort. Of these, there were 95 patients forming the clinical cohort. Subtype diagnosis was changed in 20/171 (12%) of tumours. Within the clinical cohort, there were 21/95 (22%) patients identified with higher-risk histological subtype tumours. These were associated with tumour invasiveness (P = 0.050), early recurrence (12-24 months, P = 0.013), shorter median time to recurrence (49 (IQR: 22.5-73.0) vs 15 (IQR: 12.0-25.0) months, P = 0.005) and reduced recurrence-free survival (P = 0.031). CONCLUSIONS: Application of transcription factor analysis, in addition to hormone immunohistochemistry, allows for refined pituitary tumour classification and may facilitate an improved approach to prognostication.

Patterns of surveillance for late effects of BCR-ABL tyrosine kinase inhibitors in survivors of pediatric Philadelphia chromosome positive leukemias.

BACKGROUND: Targeted anticancer therapies such as BCR-ABL tyrosine kinase inhibitors (TKIs) have improved outcomes for chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL). However, little is known about long-term risks of TKIs in children. Exposure-based survivorship guidelines do not include TKIs, thus surveillance practices may be variable. METHODS: We retrospectively examined surveillance for cardiac and endocrine late effects in children receiving TKIs for Ph + leukemias, diagnosed at < 21 years between 2000 and 2018. Frequency of echocardiogram (ECHO), electrocardiogram (EKG), thyroid stimulating hormone (TSH), dual-energy x-ray absorptiometry (DXA), and bone age testing were abstracted. Descriptive statistics were stratified by leukemia type. RESULTS: 66 patients (CML n = 44; Ph + ALL n = 22) met inclusion criteria. Among patients with CML, ≥1 evaluation was done: ECHO (50.0%), EKG (48.8%), TSH (43.9%), DXA (2.6%), bone age (7.4%). Among patients with Ph + ALL, ≥1 evaluation was done: ECHO (86.4%), EKG (68.2%), TSH (59.1%), DXA (63.6%), bone age (44.4%). Over a median 6.3 and 5.7 years of observation, respectively, 2% of patients with CML and 57% with Ph + ALL attended a survivorship clinic. CONCLUSIONS: Despite common exposure to TKIs in survivors of Ph + leukemias, patterns of surveillance for late effects differed in CML and Ph + ALL, with the latter receiving more surveillance likely due to concomitant chemotherapy exposures. Targeted therapies such as TKIs are revolutionizing cancer treatment, but surveillance for late effects and referral to survivorship clinics are variable despite the chronicity of exposure. Evidence based guidelines and longer follow-up are needed.

Calcium/calmodulin-dependent kinases can regulate the TSH expression in the rat pituitary.

PURPOSE: The endocrine secretion of TSH is a finely orchestrated process controlled by the thyrotropin-releasing hormone (TRH). Its homeostasis and signaling rely on many calcium-binding proteins belonging to the "EF-hand" protein family. The Ca2+/calmodulin (CaM) complex is associated with Ca2+/CaM-dependent kinases (Ca2+/CaMK). We have investigated Ca2+/CaMK expression and regulation in the rat pituitary. METHODS: The expression of CaMKII and CaMKIV in rat anterior pituitary cells was shown by immunohistochemistry. Cultured anterior pituitary cells were stimulated by TRH in the presence and absence of KN93, the pharmacological inhibitor of CaMKII and CaMKIV. Western blotting was then used to measure the expression of these kinases and of the cAMP response element-binding protein (CREB). TSH production was measured by RIA after time-dependent stimulation with TRH. Cells were infected with a lentiviral construct coding for CaMKIV followed by measurement of CREB phosphorylation and TSH. RESULTS: Our study shows that two CaM kinases, CaMKII and CaMKII, are expressed in rat pituitary cells and their phosphorylation in response to TRH occurs at different time points, with CaMKIV being activated earlier than CaMKII. TRH induces CREB phosphorylation through the activity of both CaMKII and CaMKIV. The activation of CREB increases TSH gene expression. CaMKIV induces CREB phosphorylation while its dominant negative and KN93 exert the opposite effects. CONCLUSION: Our data indicate that the expression of Ca2+/CaMK in rat anterior pituitary are correlated to the role of CREB in the genetic regulation of TSH, and that TRH stimulation activates CaMKIV, which in turn phosphorylates CREB. This phosphorylation is linked to the production of thyrotropin.

Interference of anti-streptavidin antibodies: More common than we thought? In relation to six confirmed cases.

Automated immunoassays are extensively used in routine laboratory diagnostics of endocrine disorders because of their advantages, such as high sensitivity, precision, and specificity. However, these methods are limited by the susceptibility of the immunochemical reaction to various interferences. They may present interferences related to the assay's design, for example, the endogenous presence of anti-streptavidin antibodies (ASA) in platforms that use the biotin-streptavidin interaction. To date, there have been few reports in the literature of interference from endogenous ASA. However, such antibodies would potentially lead to falsely decreased or increased results of hormones that can lead to incorrect diagnoses. We report six patients with unusual thyroid function tests, incongruent to their clinical findings. They present elevated concentrations of total T3 and T4 and TSH values within the reference range when measured at Cobas 8000® e801 module (Roche Diagnostics®). Neither patient had been taking biotin; however, all demonstrated the presence of ASA causing falsely high results on competitive assays and also falsely low results on sandwich assays. The hormone panel was also analyzed in the same samples using a different platform available in our laboratory: Cobas 6000® e601 module (Roche Diagnostics®). Nine samples were sent to an external laboratory to be measured with the chemiluminescent method: ADVIA Centaur® (Siemens® Healthcare Diagnostics). The interference seems to affect e801 module and competitive assays the most without affecting results obtained by this chemiluminescent method. This interference could potentially affect other assays performed on the same platform, such as ATPO and estradiol. Finally, laboratories should suspect the presence of interference when there is no correlation between the hormone profile and the patient's clinic. The biotin neutralization protocol demonstrated its effectiveness to eliminate ASA interference.

A retrospective study of pituitary-thyroid interaction in patients with first-episode of bipolar disorder type I in Mania State.

ABSTRACT: Bipolar disorder (BD)-mania is related to the dysfunction of anterior pituitary gland, but the pituitary-thyroid interaction on the acute stage of BD has been controversial. In order to rule out the effects of drugs, we aimed to determine the upstream interaction of first-episode of BD type I in mania state, and tried to find the relationship between thyroid-stimulating-hormone (TSH) and Prolactin (PRL)This study included 70 real-world patients diagnosed with first-episode BD-mania recuited and 70 healthy controls (HC) matched for age and sex from 2016 to 2017 in the same district of Shanghai. We compared the levels of thyroid hormones and prolactin between the two groups, and linear regression and curve estimation were used for the correlation analysis of TSH and PRLThere were differences in triiodothyronine (TT3), total thyroxin (TT4), and free thyroxine (FT4) concentrations between the groups (P's < .05). After being grouped by sex, higher PRL in the male and female BD-mania subgroup were observed compared to each isosexual HC [(P's < .01, Cohen's d = 0.82/1.08, 95%CI (0.33, 1.31)/(0.58, 1.58)]. Higher FT4 in the male BD-mania group was observed compared to the HC males [(P's  < .01, Cohen's d = 0.90, 95%CI (0.41, 1.39)] while the female BD-mania group showed lower TT3 and TT4 compared to the HC females [(P's  < .01, Cohen's d = 0.93/0.88, 95%CI (0.43, 1.42)/(0.39, 1.37)]. In the female BD-mania group, correlation analysis established an inverse relationship between PRL and TSH (r2 = 0.25, F = 11.11, P < .01).The findings demonstrate that sex impacts the concentration of hormones secreted by the anterior pituitary of patients with first-episode BD-mania. The increased PRL may be a putative mechanism that underlies the onset in female patients with a moderate inverse relationship between TSH and PRL. Thyroid hormones and prolactin levels may be developed as potential markers for identifying BD-manic.

Heterophilic antibody interference with TSH measurement on different immunoassay platforms.

INTRODUCTION: Interference due to the presence of heterophilic antibodies may lead to falsely low or high analyte concentrations, but falsely elevated values are more common in most immunoassay platforms. We report a case of a 53-y old female patient underwent radical thyroidectomy for thyroid papillary carcinoma and the results of TSH in the Siemens Advia Centaur XP after surgery were not suppressed, ranging from 5.73 and 6.61 µIU/ml. METHODS: The status of the thyroid was then assessed using 4 assay platforms from Siemens, Abbott, Roche and Beckman. RESULTS: The results of TSH were 5.52, 0.54, 0.12, and <0.015 µIU/ml, respectively. After the samples were pretreated with the heterophilic antibody blocker, results given by Siemens, Abbott, and Roche showed significant decreases of 0.003, 0.001, and 0.005 µIU/ml, respectively. Therefore, it was confirmed that the presence of heterophilic antibodies in the patient samples interfered with the TSH measurements in multiple assay systems. CONCLUSIONS: Clinicians must be aware of the possible assay interference, including the measurements of FT4, FT3 and TSH, results may be misleading in the presence of heterophilic antibodies, in particular when the results of thyroid function tests do not fit the patient clinical presentation.

Assessment of Prevalence and Cost of Care Cascades After Routine Testing During the Medicare Annual Wellness Visit.

Importance: For healthy adults, routine testing during annual check-ups is considered low value and may trigger cascades of medical services of unclear benefit. It is unknown how often routine tests are performed during Medicare annual wellness visits (AWVs) or whether they are associated with cascades of care. Objective: To estimate the prevalence of routine electrocardiograms (ECGs), urinalyses, and thyrotropin tests and of cascades (further tests, procedures, visits, hospitalizations, and new diagnoses) that might follow among healthy adults receiving AWVs. Design, Setting, and Participants: Observational cohort study using fee-for-service Medicare claims data from beneficiaries aged 66 years and older who were continuously enrolled in fee-for-service Medicare between January 1, 2013, and March 31, 2015; received an AWV in 2014; had no test-relevant prior conditions; did not receive 1 of the 3 tests in the 6 months before the AWV; and had no test-relevant symptoms or conditions in the AWV testing period. Data were analyzed from February 13, 2019, to June 8, 2020. Exposure: Receipt of a given test within 1 week before or after the AWV. Main Outcomes and Measures: Prevalence of routine tests during AWVs and cascade-attributable event rates and associated spending in the 90 days following the AWV test period. Patient, clinician, and area-level characteristics associated with receiving routine tests were also assessed. Results: Among 75 275 AWV recipients (mean [SD] age, 72.6 [6.1] years; 48 107 [63.9%] women), 18.6% (14 017) received at least 1 low-value test including an ECG (7.2% [5421]), urinalysis (10.0% [7515]), or thyrotropin test (8.7% [6534]). Patients were more likely to receive a low-value test if they were younger (adjusted odds ratio [aOR], 1.69 for ages 66-74 years vs ages ≥85 years [95% CI, 1.53-1.86]), White (aOR, 1.32 compared with Black [95% CI, 1.16-1.49]), lived in urban areas (aOR, 1.29 vs rural [95% CI, 1.15-1.46]), and lived in high-income areas (aOR, 1.26 for >400% of the federal poverty level vs <200% of the federal poverty level [95% CI, 1.16-1.37]). A total of 6.1 (95% CI, 4.8-7.5) cascade-attributable events per 100 beneficiaries occurred in the 90 days following routine ECGs and 5.4 (95% CI, 4.2-6.5) following urinalyses, with cascade-attributable cost per beneficiary of $9.62 (95% CI, $6.43-$12.80) and $7.46 (95% CI, $5.11-$9.81), respectively. No cascade-attributable events or costs were found to be associated with thyrotropin tests. Conclusions and Relevance: In this study, 19% of healthy Medicare beneficiaries received routine low-value ECGs, urinalyses, or thyrotropin tests during their AWVs, more often those who were younger, White, and lived in urban, high-income areas. ECGs and urinalyses were associated with cascades of modest but notable cost.

Laboratory interference in the thyroid function test.

Thyroid hormones and thyroid-stimulating hormone (TSH) laboratory tests are commonly used worldwide, and their results have an important influence on decisions about treatment and further diagnostic processes. Any discrepancies between symptoms and laboratory results or between results of different tests should be closely investigated to avoid misdiagnosis and unnecessary treatment. Inconsistencies in hormone tests might be a result of physiological changes in hormonal balance, a disease, drug intake, or laboratory interference. Major factors that interfere with thyroid function tests are: heterophilic antibodies, macro TSH, biotin, thyroid hormones autoantibodies, anti-streptavidin, and anti-ruthenium antibodies. In this paper we discuss the influence of different factors on the procedures of hormonal immunoassays, as well as methods to minimise the risk of false results and misdiagnoses.