Thyroiditis can be classified as acute, subacute, or chronic. Acute thyroiditis is often caused by infectious agents and is characterized by neck pain, fever, and difficulty swallowing. Diagnosis involves blood tests and imaging. Treatment consists of antibiotics and drainage of abscesses. Chronic thyroiditis includes Hashimoto's thyroiditis, an autoimmune disease that causes hypothyroidism. It most commonly presents as a painless neck mass and is diagnosed through blood tests showing thyroid antibodies. Treatment involves thyroid hormone replacement. Riedel's thyroiditis is a rare form of chronic thyroiditis involving fibrosis of the thyroid gland.

1. THYROIDITIS

2. THYROIDITIS
 Thyroiditis usually is classified into acute,
subacute, and chronic forms.

3. Acute (Suppurative) Thyroiditis
 It is an acute inflammation of thyroid gland.
 Infectious agents can seed it (a) via the
hematogenous or lymphatic route,
 (b) via direct spread from persistent pyriform
sinus fistulae or thyroglossal duct cysts
 (c) as a result of penetrating trauma to the
thyroid gland,
 (d) due to immunosuppression.

4.  Acute suppurative thyroiditis is more common in
children and often is preceded by an upper
respiratory tract infection or otitis media.
 It is characterized by severe neck pain radiating
to the jaws or ear, fever, chills, odynophagia,
and dysphonia.
 Complications such as systemic sepsis, tracheal
or esophageal rupture, jugular vein thrombosis,
laryngeal chondritis, and perichondritis or
sympathetic trunk paralysis may also occur.

5. Diagnosis
 The diagnosis is established by leukocytosis on
blood tests and FNAB for Gram's stain, culture,
and cytology.
 CT scans may help to delineate the extent of
infection.
 A persistent pyriform sinus fistula should always
be suspected in children with recurrent acute
 thyroiditis. A barium swallow demonstrates the
anomalous tract with 80% sensitivity.

6. Treatment
 Treatment consists of parenteral
antibiotics
 Drainage of abscesses.
 Patients with pyriform sinus fistulae
require complete resection of the sinus
tract, including the area of the thyroid
where the tract terminates, to prevent
recurrence

7. Chronic
Thyroiditis

8. Lymphocytic (Hashimoto's) Thyroiditis
 Lymphocytic thyroiditis was first described
by Hashimoto in 1912 as struma
lymphomatosa—a transformation of
thyroid tissue to lymphoid tissue.
 It is the most common inflammatory
disorder of the thyroid and the leading
cause of hypothyroidism.

9. Etiology, Pathogenesis, and
Pathology
 Autoimmune disease
 Hypothyroidism results not only from the
destruction of thyrocytes by cytotoxic T
cells but by autoantibodies.
 Chronic thyroiditis also has been
associated with increased intake of iodine
and administration of medications such as
interferon- , lithium, and amiodarone.

10. Clinical Presentation
 Hashimoto's thyroiditis is also more common in women
(male:female ratio 1:10 to 20 ) between the ages of 30
and 50 years old.
 The most common presentation is that of a minimally or
moderately enlarged firm granular gland discovered on
routine physical examination or the awareness of a
painless anterior neck mass
 although 20% of patients present with hypothyroidism,
and
 5%present with hyperthyroidism (Hashitoxicosis).
 In classic goitrous Hashimoto's thyroiditis, physical
examination reveals a diffusely enlarged, firm gland,
which also is lobulated. An enlarged pyramidal lobe often
is palpable.

11. Diagnostic Studies
 When Hashimoto's thyroiditis is suspected
clinically, an elevated TSH and the presence of
thyroid autoantibodies usually confirm the
diagnosis.
 FNAB is indicated in patients who present with a
solitary suspicious nodule or a rapidly enlarging
goiter.
 Thyroid lymphoma is a rare but well-recognized,
ominous complication of chronic autoimmune
thyroiditis.

12. Treatment
 Thyroid hormone replacement therapy is indicated in
overtly hypothyroid patients, with a goal of maintaining
normal TSH levels. The
 management of patients with subclinical hypothyroidism
(normal T4 and elevated TSH) is controversial.
Treatment is advised
 especially for middle-aged patients with cardiovascular
risk factors such as hyperlipidemia or hypertension and
in pregnant
 patients.15 Treatment also is indicated in euthyroid
patients to shrink large goiters. Surgery may
occasionally be indicated for
 suspicion of malignancy or for goiters causing
compressive symptoms or cosmetic deformity

13. Riedel's Thyroiditis
 Riedel's thyroiditis is a rare variant of
thyroiditis also known as Riedel's struma
or invasive fibrous thyroiditis that is
characterized by
 the replacement of all or part of the thyroid
parenchyma by fibrous tissue, which also
invades into adjacent tissues.

14. Etiology
 The etiology of this disorder is controversial, and
it has been reported to occur in patients with
other autoimmune diseases. This association,
 coupled with the presence of lymphoid infiltration
and response to steroid therapy, suggests a
primary autoimmune etiology.
 Riedel's thyroiditis also is associated with other
focal sclerosing syndromes including
mediastinal, retroperitoneal, periorbital, and
 retro-orbital fibrosis and sclerosing cholangitis,
suggesting that it may, in fact, be a primary
fibrotic disorder.

15. Clinical picture
 The disease occurs predominantly in women
between the ages of 30 to 60 years old. It
typically presents as a painless, hard anterior
neck mass, which progresses over weeks to
years to produce symptoms of compression,
including dysphagia, dyspnea, choking, and
hoarseness.
 Patients may present with symptoms of
hypothyroidism and hypoparathyroidism as the
gland is replaced by fibrous tissue.

16. Diagnosis
 Physical examination reveals a hard,
"woody" thyroid gland with fixation to
surrounding tissues.
 The diagnosis needs to be confirmed by
open thyroid biopsy, because the firm and
fibrous nature of the gland renders FNAB
inadequate.

17. Treatment
 Surgery is the mainstay of the treatment. The
chief goal of operation is to decompress the
trachea by wedge excision of the thyroid isthmus
and to make a tissue diagnosis.
 More extensive resections are not advised due
to the infiltrative nature of the fibrotic process
that obscures usual landmarks and structures.


18. Treatment
 Hypothyroid patients are treated with
thyroid hormone replacement.
 Some patients who remain symptomatic
have been reported to experience
dramatic improvement after treatment with
corticosteroids and tamoxifen