1. Thyroid Nodules

Thyroid nodules are very common, they may be present in up to 70% of people.  Majority of them are benign.  Any new thyroid nodule or a thyroid nodule that has recently changed should be investigated to exclude cancer.  Any history of exposure to high levels of radiation or family history of thyroid cancer are very important. The most important investigation is ultrasound of the thyroid. 

Recently The American College of Radiology and The American Thyroid Association have developed a set of standard criteria for reporting of the thyroid nodules TR1-TR5 to provide recommendations of management of these thyroid nodules. Depending on the TR classification, some of these nodules do not require any further investigation or follow-up.  Some may only require follow-up with ultrasound and some may require biopsy. 

Cysts

Cysts are fluid collections within thyroid gland.  Most of the time you may not even know that they are there.  Sometimes they become large and they need to be aspirated with a needle and they may completely disappear.  At times they will recur and very rarely thyroid surgery (thyroid lobectomy) will be performed.

Colloid Nodules

Colloid Nodules are made up of thyroid tissue that have become large.  Sometimes they are solitary, but more commonly there are many of these nodules present.   At times fine needle aspiration (FNA) is required to exclude cancer.  At times these may become very large and cause pressure symptoms or cosmetic deformity.  If thyroid nodules are symptomatic, they may need removal of part or whole thyroid gland.

Thyroid Adenomas

Thyroid adenomas are benign tumours caused by abnormal growth of thyroid cells.  They do not metastasise (spread) or invade other tissues.  The biggest problem is that these nodules are extremely difficult to be differentiated from thyroid cancer on FNA.  Thyroid surgery is often recommended for diagnosis and usually consists of thyroid lobectomy.

Thyroid Goitre

It is a term used for enlarged thyroid.  This enlargement is commonly caused by presence of nodule or nodules.  At times it is also caused by Grave’s disease.

2. Hyperactive Thyroid (Hyperthyroidism Orthyrotoxicosis)

Hyperthyroidism is caused by excess thyroid hormone.  The symptoms may be: decrease or increase in appetite and weight, difficulty sleeping, fatigue, frequent bowel motions, heart racing, heat intolerance and sweating, irritability, change in periods, muscle weakness, tremor, dizziness, thinning of hair, itching etc.  Hyperthyroidism is diagnosed by performing a blood test and measuring thyroid hormones and TSH.  If thyrotoxicosis is not treated it may lead to problems with heart and heart failure, problems with fertility or osteoporosis.

The Causes of Hyperthyroidism

The causes of hyperthyroidism may be due to excess iodine ingestion or thyroid hormone ingestion, inflammation of the thyroid (thyroiditis), solitary toxic nodule, multiple toxic nodules (thyrotoxic goiter) or due to Grave’s disease.  These are best managed to endocrinologists, rated then endocrine or thyroid surgeon. 

Treatment of Hyperthyroidism

Treatment of hyperthyroidism usually consist of medical control of thyrotoxicosis with medications such as Carbimazole or Propothyouracil.  If the treatment of thyrotoxicosis is unlikely to resolve with medications or medications are not tolerated, then the endocrinologist may recommend either radioactive iodine or surgery as treatment options.

Radioactive Iodine

It is taken as a tablet and its absorption is concentrated in the thyroid. This usually requires admission to hospital for few days. The radiation causes injury and death of thyroid tissue.  The effect is not immediate and it may take around 3 months for this to occur.   The radioactive iodine is excreted in the urine, faeces and sweat over 1-2 weeks and during this time contact restrictions may be imposed to minimize effect of radiation to other people especially children and pregnant women).
   
Thyroid surgery may consist of hemithyroidectomy or total thyroidectomy.  Hemithyroidectomy is removal of a  lobe or ½ of thyroid gland.  Total thyroidectomy is removal of whole thyroid gland.  Hemithyroidectomy is usually performed in patients who have solitary nodule causing thyrotoxicosis.  Total thyroidectomy is usually performed for Thyroitoxic multinodular goiter or for Grave’s disease.

Underactive Thyroid (Hypothyroidism)

Hypothyroidism is caused by lack of thyroid hormone.  It is usually caused by failure of thyroid to produce enough thyroid hormone or can be a consequence of having thyroid surgery.  Other causes are lack of iodine in the diet or Hashimoto’s thyroiditis. 

The symptoms

They may be poor ability to tolerate cold, tiredness, constipation, depression, weight gain.  Hypothyroidism is diagnosed by performing a blood test and measuring thyroid hormones and TSH.  If hypothyroidism is not treated it may lead to myxedema, a condition that causes swelling of tissues.  This may lead to mental deterioration, psychosis, coma, hypothermia, low heart rated, heart failure and shortness of breath.

Treatment

It consists of taking thyroid replacement medications, usually in the form of thyroxine.  Treatment never consists of surgery.