How do paediatricians use and monitor antithyroid drugs in the UK? A clinician survey

Abstract

Objective We aimed to document current practice in the medical management of paediatric hyperthyroidism in the UK and compare to international recommendations. Design A 27‐question online survey distributed via an electronic newsletter in August 2018. Participants Responses from 48 members (11%) of the British Society for Paediatric Endocrinology and Diabetes. Measurements Information about antithyroid drug (ATD) preference, treatment duration, monitoring of full blood count (FBC), management of neutropaenia, agranulocytosis screening and patient education. Results Carbimazole is favoured by 98% of respondents and a “dose titration” regimen preferred over “block and replace” (65% vs 29%). TRAbs (thyroid‐stimulating hormone receptor antibodies) are used for diagnostic purposes by 85% and by 33% to look for evidence of disease remission. The majority (81%) treat for a minimum of 2 years before considering a trial off ATD. All respondents reported that they “always/usually” warn their patients about the risk of agranulocytosis before starting ATD, but written information is “rarely/never” provided by 63%. Sore throat (98%) and fever (92%) are the most commonly cited symptoms used to alert a patient to possible agranulocytosis. FBC is measured prior to treatment by 65% and measured periodically during treatment by 70%. Conclusions The management of paediatric hyperthyroidism with ATDs in the UK is not consistent with all international recommendations because a block and replace ATD regimen remains widely used. TRAbs are utilized at presentation, but underused for detecting disease remission. National consensus guidelines and written patient information may refine the management of paediatric patients on ATDs.

How to use thionamide anti-thyroid drug in the young– what’s new?

“…A key underlying premise for those who advocate BR is that it is easier to replace thyroxine in an appropriate quantity in the 'blocked' Graves' patient than it is to adjust the ATD dose in a way that renders the hyperthyroid patient euthyroid. The American Thyroid Association guideline that recommend the DT strategy does so on the basis that the likelihood of side effects is reduced [28,29] but some clinicians continue to feel that biochemical stability is better with BR [30] and this strategy is still used regularly by paediatricians in the UK [31,32]. The potential benefits of one approach versus the other may be different in childhood because the underlying disease tends to be more severe and because the young, growing person is changing in size with an associated change in thyroid hormone requirement.…”

Randomised trial of block and replace vs dose titration thionamide in young people with thyrotoxicosis

“…A recent audit suggested improved biochemical control in paediatric patients managed with BR but patient numbers were small and individuals managed with BR had been on ATD for longer (22). Paediatric endocrinologists in the UK still use the BR strategy (23) which may indicate that some clinicians feel that BR is a useful strategy in selected patients where DT does not result in biochemical stability.…”

Updates in the Management of Graves Disease in Children

“…Although the 2016 ATA guidelines recommended against the use of BR regimens based on these findings [8], they continue to be utilized in clinical practice, particularly for patients who experience fluctuations in thyroid function with only minimal changes in MMZ dosage. A 2018 survey in the UK revealed that BR regimens were still commonly used among pediatric endocrinologists, with 29% favoring BR compared to 65% using DT [21].…”