Ministry of Health and Family Welfare, Government of India has issued the Standard Treatment Guidelines for Thyrotoxicosis.
Following are the major recommendations :
Thyrotoxicosis refer to clinical syndrome of toxicosis associated with excess circulating thyroid hormones which may or may not be associated with increased gland activity while hyperthyroidism is associated with increased gland activity and increased levels of circulating thyroid hormones. Therefore, all patients with hyperthyroidism are thyrotoxic while vice versa is not true.
The common cause of thyrotoxicosis include Graves’ disease, toxic multinodular goitre (MNG), toxic adenoma and thyroidits. The symptoms associated with thyrotoxicosis include weight loss, despite increased appetite, palpitation, heat intolerance, fatigue, weakness, frequent motions and trembling. The signs include tachycardia, tremor, warm moist skin, goitre (96%), hyperreflexia eye signs and dermopathy®. Grades of goiter grading as per WHO classification include a) Grade 0: Thyroid neither palpable nor visible. b). Grade 1: Thyroid palpable but not visible with neck in normal position c). Grade 2:Thyroid palpable and visible with neck in normal position The monosymptomatic manifestation of thyrotoxicosis include malabsorption syndrome, loan atrial fibrillation, attention deficiency disorder, tall stature & hypokalemic/hyperkalemic periodic paralysis.
The diagnosis of hyperthyroidism is based on increased T3, T4 and suppressed TSH (<0.05 µU/ml) with clinically evident toxicosis. The usefulness of 99mTc scan is only in a situation when there is a clinical suspicious of thyroiditis particularly when there is history of fever, neck pain, rapid weight loss and tender goitre. 99mTc scan is also useful in establishing a diagnosis of toxic adenoma. Estimation of TPO antibody is not required, however it is positive in significant titres in 70-80% of patients with Graves’ disease and its presence is a marker of autoimmune thyroid disease. Ultrasonography is useful for establishing a diagnosis of multinodular goitre as sometimes a single large nodule is only present clinically.
Treatment of thyrotoxicosis include drugs, (thionamides) 131radioablation after failure of drug treatment and rarely surgery if goitre is very large (III/IV). The drug treatment include the use of neomercazole (NMZ) in doses of 30-40 mg per day usually in a single daily dose preferably in the morning fasting state. The doses higher than this does not yield any additional benefit. However, the NMZ should be administered in three divided doses if patient is severely toxic. Use of non iodized salt is currently recommended along with NMZ to avoid iodine as a fuel to hyperthyroid gland. The NMZ doses are gradually tapered once the patient becomes euthyroid that usually spans over 3 months and continued for 24 months usually in doses of 5mg as even this minimum dose possesses immunomodulatory action. There is no extra-benefit of extending the treatment beyond 24 months in preventing the recurrence of disease. The disease is said to be in remission when the patients remains euthyroid at least for a period of one year after stoppage of treatment. However, remission rate is around 40-50%, therefore majority of the patients required reintroduction of drug or ablative treatment. Management of associated thyroid orbitopathy include methyl prednisolone in low dose pulse therapy (4.5 gm over 8 weeks) and if failed to response addition of azathropine is recommended. Recently rituximab has been used for orbitopathy with success.
Guidelines by The Ministry of Health and Family Welfare :
Dr Sailesh Lodha
Fortis Escorts Jaipur