Download MBBS Surgery Presentations 55 Thyroiditis Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) 1st Year, 2nd Year, 3rd Year and Final year Surgery 55 Thyroiditis PPT-Powerpoint Presentations and lecture notes


Thyroiditis

Hashimoto's

De-quervain's, Reidel's

Solitary thyroid nodule approach

Dept of Surgery

Thyroiditis

? Inflammation of the thyroid gland

? Acute illness

? Severe thyroid pain

? Manifested primarily by thyroid dysfunction
Types

Acute

? Streptococcus and anaerobes (70% Escherichia coli, Pseudomonas

(Suppurative)

aeruginosa, Haemophilus influenzae, Eikenel a corrodens,

Thyroiditis

Corynebacterium, Coccidiomycosis species

? More common in children

? Diagnosis : leukocytosis on blood tests and FNA biopsy for Gram's stain,

culture, and cytology

? Treatment : parenteral antibiotics and drainage of abscesses

Subacute

? Painful or painless

Thyroiditis

? Post viral inflammatory response, Genetic predisposition, autoimmune

? TSH is decreased, and thyroglobulin, T4 and T3 levels are elevated

? beta blockers and thyroid hormone replacement (after hyperthyroid

phase)

? Surgery for recurrent attacks

Chronic

? Hashimoto's

Thyroiditis

? Reidel's

? De-quervain's

Hashimoto Thyroiditis

? First described by hashimoto, in 1912, as struma

lymphomatosa--

? Transformation of thyroid tissue to lymphoid tissue

? Most common inflammatory disorder of the thyroid

? Leading cause of hypothyroidism
Etiology

? Autoimmune process
? Increased intake of iodine
? Medications: interferon, lithium, and amiodarone
? Inherited predisposition
? Chromosomal abnormalities : turner's syndrome and

down syndrome.

? Associations with hla-b8, dr3, and dr5 haplotypes

Pathogenesis

Activation of CD4+T (helper) lymphocytes
T cells recruit cytotoxic CD8+T cells to the thyroid.
Hypothyroidism results from:

? destruction of thyrocytes by cytotoxic t cells
? autoantibodies, which lead to complement fixation and killing by natural

killer cells or block the TSH receptor

Antibodies are directed against the three main antigens

? Tg (60%)
? TPO (95%)
? TSH-R (60%)
? sodium/iodine symporter (25%)

Apoptosis (programmed cell death) also implicated




Pathology

? Gland is diffusely infiltrated by small

lymphocytes and plasma cells,

occasionally shows well-developed

germinal centers

? Thyroid follicles are smaller than normal

with reduced amounts of colloid and

increased interstitial connective tissue

? Follicles are lined by h?rthle or

askanazy cel s, which are characterized

by abundant eosinophilic, granular

cytoplasm.
Clinical Presentation

? Male: female ratio 1:10 to 20)
? Ages of 30 and 50 years.
? Minimal y or moderately enlarged firm gland
? 20% of patients present with hypothyroidism
? 5% present with hyperthyroidism ( hashitoxicosis)

Diagnostic Studies

TSH T4 and T3 levels

Thyroid autoantibodies

FNA biopsy if solitary suspicious nodule or a

rapidly enlarging goiter
Treatment

Overtly hypothyroid:

? Thyroid hormone replacement therapy

Subclinical hypothyroidism:

? Male patients

? TSH greater than 10 mu/L

? Euthyroid patients to shrink large goiters

? Surgery may occasional y be indicated for suspicion of malignancy

or for goiters causing compressive symptoms or cosmetic

deformity

De Quervain's thyroiditis

? First described in 1904
? Granulomatous thyroiditis
? Viral infections: Adenovirus, Coxsackievirus, Influenza

virus, Epstein barr virus, Mumps, Echovirus & Enterovirus

? Less common than Hashimoto's thyroiditis
? Gland swel s up is very painful and tender
? Patient becomes hyperthyroid but the gland cannot take

up iodine so the radioactive iodine uptake is very low
? Absence of thyroid antibodies differentiates this

condition from autoimmune thyroiditis

? Recovery is invariably complete and response to

prednisolone is so dramatic that it is almost diagnostic

Riedel's Thyroiditis

? Riedel's struma or invasive fibrous thyroiditis

? Replacement of al or part of the thyroid parenchyma by

fibrous tissue

Etiology :

? Autoimmune diseases, such as pernicious anemia and

graves' disease

? Mediastinal, retroperitoneal, periorbital, and retro-orbital

fibrosis

? Sclerosing cholangitis
? Women between the ages of 30 and 60 years.
Presentation:

? Painless, hard anterior neck mass

? Dysphagia

? Dyspnea

? Choking

? Hoarseness

? Symptoms of hypothyroidism & hypoparathyroidism

? Hard, "woody" thyroid gland

Diagnosis:

? Open thyroid biopsy

Treatment:

? Surgery

? Thyroid hormone replacement

? Corticosteroids and tamoxifen

Solitary Thyroid Nodule

An isolated nodule in the thyroid gland

Benign:

? Cysts

? Adenoma-

? Papil ary

? Fol icular

? Hurthle cel type

? Toxic Adenoma- solitary hyper-functioning thyroid nodule

? Non toxic Adenoma-solitary nonfunctioning thyroid nodule

Malignant:

? Primary

? Metastatic


? Nodules common, whereas cancer relatively uncommon

? Higher in women (1.2:1 4.3:1)

? Estimated 5-15% of nodules are cancerous

? Although cancer more common in women, a nodule in a man

is more likely to be cancer

Workup of a solitary thyroid nodule
Laboratory Studies

Most patients with thyroid nodules are euthyroid
? Blood TSH level
? Serum Tg levels
? Serum calcitonin levels
? RET oncogene mutations
? 24-hour (urine) for vanillylmandelic acid (VMA),

metanephrine, and catecholamine

Imaging

Ultrasound is helpful for:

? detecting nonpalpable thyroid nodules

? differentiating solid from cystic nodules

? identifying adjacent lymphadenopathy

? Fol ow up of size of suspected benign nodules

CT and MRI are unnecessary in the routine evaluation

of thyroid tumors, except for large, fixed, or substernal

lesions.

Scanning the thyroid with 123I or 99mTc for evaluating

patients for "hot" or autonomous thyroid nodules
Management

? Malignant tumors are treated by thyroidectomy
? Simple thyroid cysts: aspiration
If the cyst persists after three attempts at aspiration,
unilateral thyroid lobectomy is recommended.
? Lobectomy is also recommended for:

? cysts greater than 4 cm in diameter
? complex cysts with solid and cystic components

Management

? If a colloid nodule is diagnosed by FNA biopsy, patients should

still be observed with serial ultrasound and Tg measurements.

? l-thyroxine in doses sufficient to maintain a serum TSH level

between 0.1 and 1.0 U/mL may also be administered.

? Thyroidectomy should be performed if:

? Nodule enlarges on TSH suppression, compressive symptoms
? Cosmetic reasons
? H/o previous irradiation of the thyroid gland
? Family history of thyroid cancer

This post was last modified on 08 April 2022