Evaluating Thyroid Disorders ENT for the PA-C Andrew Golde MD,CM FRCSC FACS Advanced Ear, Nose and...
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Transcript of Evaluating Thyroid Disorders ENT for the PA-C Andrew Golde MD,CM FRCSC FACS Advanced Ear, Nose and...
Evaluating Thyroid Disorders ENT for the PA-C
Andrew Golde MD,CM FRCSC FACS
Advanced Ear, Nose and Throat Associates
Atlanta, GA
February 2011
Common Thyroid Disorders
• Hyperthyroidism
• Hypothyroidism
• Thyroiditis
• Thyroid nodules/goiter
• Thyroid tumors
• Thyroglossal duct cysts
Thyroid Evaluation
• History
• Physical exam
• Bloodwork
• Imaging studies
• Tissue analysis
Thyroid Testing 2
• Functional– Bloodwork– Nuclear scans
• Anatomic– Imaging (U/S, CT,
PET/CT)– Needle biopsy
History Details
• Hyperthyroidism– PMA (pretty much
anything)– Feel worse than
hypothyroid patients
• Hypothyroidism– PMA– “Weight gain”
Physical examination of thyroid
• Stand front or back• Feel laryngeal
framework and hyoid
• Have pt swallow or drink
• Size of gland• Nodule?• Tender?
Thyroid Function Testing
• Imaging– Radioiodine uptake
• Differentiate among causes of hyperthyroidism
• Graves vs toxic nodule
• Bloodwork– Total T4 and T3– Free T4 and T3– TSH ********* !!!!!!!!!– TRH stimulation– Thyroglobulin– Thyroid antibodies
• TPOAb
• TgAb
• TSHRAb
TSH testing
• Concentration of free T4 genetically determined
• Small variations in T4 produce large variations in TSH
• -----> TSH is more sensitive test• -----> TSH is only test required to screen
patients for thyroid dysfunction• Age related variations (old low; young high)
Thyroglobulin (Tg)
• Protein backbone of thyroid hormone• Mostly stored in colloid• Small amounts of Tg present in blood of all
people; increaase with size of gland• Secreted by differentiated thyroid cancers• Major clinical usefulness is in follow-up of
patients with thyroid ca after their initial treatment– Tg should be undetectable
Thyroid-related antibodies
• Thyroid Peroxidase Ab (TPOAb)• Most sensitive test for autoimmune thyroid
disease (75% Graves’; 90% Hashimoto’s)• TSH Receptor Ab (TRAb)
– Cause hyperthyroidism in Graves’– 90% detectable– Not need to test for most patients
Radioiodine testing
• Useless for determining presence or absence of thyroid cancer– Ex. cold nodule
• Used to differentiate among various causes of hyperthyroidism– High uptake ---> Graves’, toxic nodule etc– Low uptake ---> thyroiditis, excessive
hormone administration, struma ovarii
Suspected hyperthyroidism
• Symptomatic– TSH normal ---> not
hyperthyroid– TSH suppressed --->
assess etiology • Ex TPOAb, TRAb
• Asymptomatic– Low TSH in older
adults– Excessive thyroid
hormone intake– Subclinical Graves’
Suspected hypothyroidism
• Symptomatic• TSH normal ---> not
hypothyroid• TSH low
– Free T4 low– TPOAb elevated– Hashimoto’s
• Asymptomatic• Low TSH in 3.5%
men and 8% women• Subclinical
Hashimoto’s
Thyroiditis
• One of most common endocrine abnormalities clinically
• Ex. Hashimoto’s
• Diverse presentation• Goiter <-----> life-threatening illness• Hypothyroidism <-----> Hyperthyroidism
Types of Thyroiditis
• Chronic lymphocytic (Hashimoto’s)
• Subacute (sporadic, postpartum, granulomatous)
• Acute suppurative
• Invasive fibrous (Riedel’s)
Hashimoto’s thyroiditis
• Most common cause of both goiter and hypothyroidism
• Most common autoimmune disorder• Painless diffuse goiter; multinodular• Young to middle aged female (30-50)• High titers TPOAb and TgAb
• Treatment = L-thyroxine
Subacute thyroiditis
• Destruction-induced thyroididities
• Abrupt onset thyrotoxicosis (leakage of T4 and Tg)
• Thyroid enlarges - painful
• Hypothyroidism ---> recovery?
• Self-limited
• Treat Sx prn (B-blocker, L-thyroxine)
The other ones
• Riedel’s thyroiditis• Invasive fibrous process• Least common• Gland hard as rock• Biopsy to r/o carcinoma
• Acute suppurative • Extremely rare• Life threatening thyrotoxicosis• Painful mass
Differential Diagnosis of Painful Neck Mass
• THYROIDAL– Thyroiditis– Hemorrhage into
cyst or nodule– Rapidly enlarging
thyroid cancer
• NONTHYROIDAL– Infected thyroglossal
duct cyst– Infected branchial
cleft cyst– Infected cystic
hygroma– Cervical adenitis– Cellulitis of neck– Globus hystericus
Evaluation of Thyroid Nodules/Goiter
• History• Time of onset• Speed of growth• Pain/discomfort• Dysphagia• Hoarseness• Airway compression• Thyroid dysfunction• Family history thyroid disease including ca• Head and neck radiation
Evaluation of Thyroid Nodules/Goiter
• Physical Exam• Palpation - size, tenderness, tracheal deviation,
lymphadenopathy• Laryngoscopy (if available) - vocal fold function• Auscultation of chest - biphasic stridor• Visual inspection - retrosternal
Thyroid Imaging
• Ultrasound
• CT scan of neck
• PET/CT
• Radionuclide scanning
Thyroid Imaging
• Ultrasound (benefits)• Gold standard imaging modality• Always first choice• 10-13 Mhz linear array; Doppler• Assess morphology, measure dimensions,
nodules, vascularity, lymphadenopathy• U/S guided FNA
Thyroid Imaging
• Ultrasound (negatives)• Incidental nodules discovered in up to 48% of
patients - 4% “incidentalomas” malignant• Provides no functional information• Poor predictor of malignancy
» Irregular margins» Microcalcifications - papillary ca
Thyroid Imaging
• CT scan• Contrast enhanced• Assess extracapsular spread, tracheal
compression and deviation, lymphadenopathy,and retrosternal extension
• Rarely CT guided FNA
Thyroid Imaging
• Nuclear Uptake Scanning (Scintigraphy)• Tc 99m or radioactive iodine (I123 or I131)• Assess functional status of thyroid nodules
– “hot” vs “cold”– Increased risk of malignancy in cold nodule
• Determine uptake of hyperthyroid gland when considering I131 ablation
• R/O lingual thyroid tissue
Thyroid Nodules/Masses
• High prevalence on palpation• 7% women, 2 % men,
• Most not clinically recognized• 57% on autopsy
• Multiple in 48% diagnoses• Incidental findings on imaging studies• Clinical concern is malignancy• Other symptoms: dysphagia, dyspnea, pain,
cosmesis, hyperfunction
Evaluation of Thyroid Nodules
• History and physical• TSH +/- thyroid Ab’s• Ultrasound• FNA
• Nuclear scanning (Hyperthyroid)• CT if suspect retrosternal extension or
malignancy
Nodules - Risk of Malignancy
• Most nodules are benign - 95%
• Age <20 and age >70
• Male
• Nodule >4cm
• Hx of radiation to head and neck
• Multinodular goiter and cysts have same risk of malignancy
Evaluation of Suspicious Thyroid Nodule
Surgery
Malignant5%
Surgery
Suspicious or Atypical20%
Follow if <4cmSurgery if >4cm
Benign75%
Diagnostic
Consider surgery
Nondiagnostic
Rebiopsy
CystRemove fluid
Follow algorithm
Diagnostic
Rebiopsy
Solid
Nondiagnostic
FNA biopsyType Title Here
Thyroglossal Duct Cyst
• Midline neck mass
• Embryologic remnant of thyroid migration
• Gradual enlargement; URTI
• Painless unless infected
• Surgical removal (Sis-Trunk procedure)
Summary
• TSH for thyroid function
• Ultrasound to assess for size, nodules
• (U/S guided) FNA to evaluate nodules
• CT neck with contrast to evaluate other masses/nodes