Search Results

You are looking at 1 - 5 of 5 items for

  • Author: W Edward Visser x
Clear All Modify Search
Free access

Kristien Boelaert, W. Edward Visser, Peter Nicholas Taylor, Carla Moran, Juliane Leger and Luca Persani

This manuscript provides guidance on the management of thyroid dysfunction during the COVID-19 pandemic. Auto-immune thyroid diseases are not linked to increased risks of COVID-19. Uncontrolled thyrotoxicosis may result in more severe complications from SARS-CoV-2 infection, including thyroid storm.

The management of patients with a new diagnosis of hyperthyroidism is best undertaken with a block and replace regimen due to limited biochemical testing availability. Antithyroid drug (ATD)-induced neutropenia may favour the progression of COVID-19 and symptoms of infection may be confused with SARS-CoV-2 infection. The withdrawal of ATDs and urgent measurement of neutrophils should be considered in case of flu-like manifestations occurring in the initial months of treatment. Urgent surgery or 131-I may be undertaken in selected cases of uncontrolled thyrotoxicosis. Patients with COVID-19 infection may present with conjunctivitis, which could cause diagnostic difficulties in patients with new or existing Graves’ ophthalmopathy.

Patients who are on replacement treatment with thyroid hormones should ensure they have sufficient supply of medication. The usual advice to increase dosage of levothyroxine during pregnancy should be adhered to.

Many newly presenting and previously diagnosed patients with thyroid dysfunction can be managed through virtual telephone or video clinics supported by a dedicated nurse-led service, depending on available facilities.

Free access

Chantal Zevenbergen, Tim I M Korevaar, Andrea Schuette, Robin P Peeters, Marco Medici, Theo J Visser, Lutz Schomburg and W Edward Visser

Background

Levels of thyroid hormone (TH) and trace elements (copper (Cu) and selenium (Se)) are important for development and function of the brain. Anti-epileptic drugs (AEDs) can influence serum TH and trace element levels. As the relationship between AEDs, THs, and trace elements has not yet been studied directly, we explored these interactions.

Method

In total 898 participants, from the Thyroid Origin of Psychomotor Retardation study designed to investigate thyroid parameters in subjects with intellectual disability (ID), had data available on serum Se, Cu, thyroid stimulating hormone (TSH), free thyroxine (FT4), tri-iodothyronine (T3), reverse T3, T4, and thyroxine-binding globulin (TBG); 401 subjects were on AED treatment. Differences in trace elements according to medication usage was investigated using ANOVA, and associations between trace elements and thyroid parameters were analysed using (non-) linear regression models.

Results

Study participants were not deficient in any of the trace elements analyzed. AED (carbamazepine, valproate and phenytoin) usage was negatively associated with serum Se and showed compound-specific associations with Cu levels. After correction for drug usage, Se was positively associated with TSH levels, negatively associated with FT4 levels, and positively with T3 levels. Cu was positively associated with T4, T3, and rT3, which was largely dependent on TBG levels.

Conclusion

The subjects with ID did not display profound deficiencies in trace element levels. AEDs were associated with serum Se and Cu levels, while serum Se and Cu were also associated with thyroid parameters. Further studies on the underlying mechanisms and potential clinical importance are warranted.

Open access

Serena Khoo, Greta Lyons, Anne McGowan, Mark Gurnell, Susan Oddy, W Edward Visser, Sjoerd van den Berg, David Halsall, Kevin Taylor, Krishna Chatterjee and Carla Moran

Objective

Familial dysalbuminaemic hyperthyroxinaemia (FDH), most commonly due to an Arginine to Histidine mutation at residue 218 (R218H) in the albumin gene, causes artefactual elevation of free thyroid hormones in euthyroid individuals. We have evaluated the susceptibility of most current free thyroid hormone immunoassay methods used in the United Kingdom, Europe and Far East to interference by R218H FDH.

Methods

Different, one- and two-step immunoassay methods were tested, measuring free T4 (FT4) and free T3 (FT3) in 37 individuals with genetically proven R218H FDH.

Results

With the exception of Ortho VITROS, FT4 measurements were raised in all assays, with greatest to lowest susceptibility to interference being Beckman ACCESS > Roche ELECSYS > FUJIREBIO Lumipulse > Siemens CENTAUR > Abbott ARCHITECT > Perkin-Elmer DELFIA. Five different assays recorded high FT3 levels, with the Siemens CENTAUR method measuring high FT3 values in up to 30% of cases. However, depending on the assay method, FT4 measurements were unexpectedly normal in some, genetically confirmed, affected relatives of index FDH cases.

Conclusions

All FT4 immunoassays evaluated are prone to interference by R218H FDH, with their varying susceptibility not being related to assay architecture but likely due to differing assay conditions or buffer composition. Added susceptibility of many FT3 assays to measurement interference, resulting in high FT4 and FT3 with non-suppressed TSH levels, raises the possibility of R218H FDH being misdiagnosed as resistance to thyroid hormone beta or TSH-secreting pituitary tumour, potentially leading to unnecessary investigation and inappropriate treatment.

Restricted access

Evert F S van Velsen, Elske T Massolt, Hélène Heersema, Boen L R Kam, Tessa M van Ginhoven, W Edward Visser and Robin P Peeters

Objective

Earlier cross-sectional studies showed that patients with differentiated thyroid cancer (DTC) have a significant reduction of quality of life (QoL) compared to controls. However, recent longitudinal studies showed mixed results and had relative short follow-up or lacked knowledge about QoL before initial surgery. Therefore, we initiated a longitudinal study to assess changes of QoL in patients undergoing treatment for DTC.

Methods

We prospectively included patients, aged 18–80 years, who were treated for DTC at a Dutch university hospital. Using questionnaires, QoL was assessed before surgery, just before radioiodine (RAI) therapy, and regularly during follow-up. Repeated measurement analysis was used to assess changes of QoL over time, and we explored the influence of different characteristics on QoL.

Results

Longitudinal QoL assessments were available in 185 patients (mean age 47 years; 71% women). All patients were treated according to the Dutch guidelines with total thyroidectomy followed by RAI (83% after thyroid hormone withdrawal). Median time between baseline and final questionnaire was 31 months, and patients completed a median of three questionnaires. QoL at baseline was lower than that in the general population, developed non-linear over time, was lowest around RAI therapy, and recovered over time. Females, younger patients, and patients with persistent hypoparathyroidism had lower QoL scores.

Conclusions

In a population of DTC patients, QoL before initial therapy is already lower than that in the general population. Thereafter, QoL develops non-linearly over time in general, with the lowest QoL around RAI therapy, while 2 to 3 years later, it approximates baseline values.

Free access

Edward Buitenwerf, Tijmen Korteweg, Anneke Visser, Charlotte M S C Haag, Richard A Feelders, Henri J L M Timmers, Letizia Canu, Harm R Haak, Peter H L T Bisschop, Elisabeth M W Eekhoff, Eleonora P M Corssmit, Nanda C Krak, Elise Rasenberg, Janneke van den Bergh, Jaap Stoker, Marcel J W Greuter, Robin P F Dullaart, Thera P Links and Michiel N Kerstens

Background

A substantial proportion of all pheochromocytomas is currently detected during the evaluation of an adrenal incidentaloma. Recently, it has been suggested that biochemical testing to rule out pheochromocytoma is unnecessary in case of an adrenal incidentaloma with an unenhanced attenuation value ≤10 Hounsfield Units (HU) at computed tomography (CT).

Objectives

We aimed to determine the sensitivity of the 10 HU threshold value to exclude a pheochromocytoma.

Methods

Retrospective multicenter study with systematic reassessment of preoperative unenhanced CT scans performed in patients in whom a histopathologically proven pheochromocytoma had been diagnosed. Unenhanced attenuation values were determined independently by two experienced radiologists. Sensitivity of the 10 HU threshold was calculated, and interobserver consistency was assessed using the intraclass correlation coefficient (ICC).

Results

214 patients were identified harboring a total number of 222 pheochromocytomas. Maximum tumor diameter was 51 (39–74) mm. The mean attenuation value within the region of interest was 36 ± 10 HU. Only one pheochromocytoma demonstrated an attenuation value ≤10 HU, resulting in a sensitivity of 99.6% (95% CI: 97.5–99.9). ICC was 0.81 (95% CI: 0.75–0.86) with a standard error of measurement of 7.3 HU between observers.

Conclusion

The likelihood of a pheochromocytoma with an unenhanced attenuation value ≤10 HU on CT is very low. The interobserver consistency in attenuation measurement is excellent. Our study supports the recommendation that in patients with an adrenal incidentaloma biochemical testing for ruling out pheochromocytoma is only indicated in adrenal tumors with an unenhanced attenuation value >10 HU.