Current RMA Instruments
| Reasonable Hypothesis SOP | 1 of 2022 |
| Balance of Probabilities SOP | 2 of 2022 |
Changes from previous Instruments
ICD Coding
- ICD-10-AM Codes: E06.3
Brief description
This is a chronic autoimmune inflammation of the thyroid gland in which the body develops cytotoxic antibodies to the thyroid gland - anti thyroid peroxidase (TPO) and anti thyroglobulin antibodies (Tg). The condition is characterized by gradual thyroid failure, with or without goitre formation.
Hashimoto thyroiditis is a common cause of hypothyroidism. There is a separate SOP for hypothyroidism, which covers other causes of decreased thyroid function, but excludes Hashimoto thyroiditis. Similarly, Hashimoto thyroiditis may cause a goitre. There is a separate SOP for goitre, which covers other causes of thyroid enlargement, but excludes Hashimoto thyroiditis. So all manifestations of Hashimoto thyroiditis are covered by the Hashimoto thyroiditis SOP only. In someone with hypothyroidism in whom a diagnosis of Hashimoto thyroiditis has not been confirmed by thyroid antibody testing, the SOP for hypothyroidism can be applied.
Confirming the diagnosis
Diagnosis is based on clinical manifestations and blood tests assessing thyroid function and the presence of thyroid antibodies.
The appropriate medical specialist is an endocrinologist.
Additional diagnoses covered by SOP
- Atrophic thyroiditis
- Chronic autoimmune thyroiditis with transient thyrotoxicosis (Hashitoxicosis)
- Chronic lymphocytic thyroiditis
- Goitrous thyroiditis
- Hashimoto’s disease
- Hashitoxicosis
- Myxoedema coma due to Hashimoto thyroiditis
- Ord’s disease – primary hypothyroidism with thyroid atrophy
Conditions excluded from SOP
- Acute thyroiditis#
- Goitre other than due to Hashimoto thyroiditis*
- Hyperthyroidism other than due to Hashimoto thyroiditis*
- Hypothyroidism other than due to Hashimoto thyroiditis*
- Non-autoimmune chronic thyroiditis#
- Postpartum thyroiditis#
- Subacute thyroiditis#
* another SOP applies
# non-SOP condition
Clinical onset
The clinical presentation is variable. In some people there may be an intial, transient hyperthyroidism. More usually, there will be an insidious onset with gradual decline in thyroid function. Some further patients may present with a goitre or, more rarely, local thyroid symptoms of pain and tenderness.
Clinical worsening
The usual course is gradual loss of thyroid function. The mainstay of treatment is thyroid replacement therapy. Standard treatment is not aimed at modifying the course of the disease or effecting a cure for the condition.