L3: Toxic Goiter Flashcards
The term thyrotoxicosis is retained. Why?
Clinical Types of Thyrotoxicosis
- Diffuse toxic goiter (Gravesβ disease).
- Toxic nodular goiter.
- Toxic nodule.
- Hyperthyroidism due to rarer causes.
Compare between diffuse toxic goiter (Graveβs) & Toxic Nodular Goiter (Plummerβs) in tertms of:
- Name
- Time
- Eye Signs
- Age
- Pathology
Def of Toxic nodule
A toxic nodule is a solitary overactive nodule.
Types of Toxic nodule
- May be part of a generalized nodularity.
- OR a true toxic adenoma.
Characters of Toxic nodule
- It is autonomous (its hypertrophy and hyperplasia are not due to TSH-RAb).
- The normal thyroid tissue surrounding the nodule is itself suppressed and inactive.
Hyperthyroidism due to rarer causes
Thyrotoxicosis factitia (drug induced)
Intake of L-thyroxine more than normal.
Jod Basedow thyrotoxicosis
Large doses of iodides given to a hyperplastic endemic.
Autoimmune thyroiditis OR de Quervainβs thyroiditis
Inflammation/destruction of the thyroid cells β inapcropriate release of thyroid hormone.
Neonatal thyrotoxicosis
It subsides in 3-4 weeks β-> as TsAb titers fall in the babyβs serum.
Struma ovarii
- A type of ovarian tumors β Ectopic hormone procuction β symptoms of hyperthyroidism.
Drugs like amiodarone (antiarrhythmic agent)
- Rich in iodine.
- Having structural similarity to T4.
- Causing thyrotoxicosis.
Histology of Toxic Goiter
Which Sex is more affected by Thyrotoxicosis?
Thyrotoxicosis is 8 times rnore common in women than in men.
What age is more affected by Thyrotoxicosis?
Any age
Signs & Symptoms of Thyrotoxicosis
Cardiac Rhythm in Thyrotoxicosis
Myopathy in Thyrotoxicosis
Eye Signs in Thyrotoxicosis
- Some degree of exophthalmos is common.
- It may be unilateral.
- Forms: (true Exophthalmus & Weakness of the extraocular muscles)
True Exophthalmous in Thyrotoxicosis
Weaknes of extraoccular muscles in Thyrotoxicosis
particularly the elevators (inferior oblique) β diplopia.
what happens regarding eye signs in Severe Thyrotoxicosis?
In severe cases, papilledema & corneal ulceration occur. When severe & progressive:
- It is known as [Malignant exophthalmos].
- Eye may be destroyed.
TTT of Eye Signs in Thyrotoxicosis
- Spasm & retraction usually disappear when the hyperthyroidism is controlled.
- Beta-adrenergic blocking drugs can improve the condition.
- Exophthalmos tends to improve with time.
..
Thyroid Dermopathy in Thyrotoxicosis
Mechanism of Thyroid Dermopathy in Thyrotoxicosis
Deposition of hyaluronic acic in dermis & subcutis.
TTT of Thyroid Dermopathy in Thyrotoxicosis
- Treat the underlying thyroid disorder.
- Topical steroids.
Compare between 1ry (Graveβs disease)
& 2ry (Plummerβs disease) in terms of:
- Age
- Hx
- Manifestations (Meta, Nerv, Cardia, occul)
- Thyroid Enlargment
- Investigations
- TTT
- Recurrence after Surgery
Clinical Investigations of Thyrotoxicosis
Non-Specific Lab Investigations in Thyrotoxicosis
Specific Lab Investigations in Thyrotoxicosis
- Serum TSH
- Thyroxine (T4) & tri-iodothyronine (T3)
- Thyroid Autoantibodies
- Thyroglobulin Estimation
- Radioactive studies
Serum TSH in Thyrotoxicosis
T3 & T4 in Thyrotoxicosis
T3 toxicity (with a normal T4) is a distinct entity
- T3 toxicity (with a normal T4) is a distinct entity..
- It may only be diagnosed by measuring the serum T3.
- Although, a suppressed TSH level with a normal T4 may suggest the diagnosis.
Thyroid Autoantibodies in Thyrotoxicosis