system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
All of the following are true about Hashimoto's thyroiditis except:
assistant
The correct answer is  . Ans. d. Orphan Annie eye nuclei Orphan Annie eye nuclei is seen in papillary carcinoma thyroid.Histological characteristics of Papillary Carcinoma Thyroid* Papillary projections: PTC contains branching papillae of cuboidal epithelial cells* Orphan Annie eye nuclei:The nuclei contain finely dispersed chromatin, which imparts an optically clear or empty appearance, giving rise to term ground glass or Orphan Annie eye nuclei.Invaginations of cytoplasm in cross-sections: Intranuclear inclusions** (pseudo-inclusion) or intranuclear grooves.Diagnosis of PTC is based on these nuclear characteristics9 even in the absence of papillary structures.* Psammoma bodies: Microscopic, calcified deposits representing clumps of sloughed cellsHashtmoto's Thyroiditis* First described by Hashimoto as struma lymphomatosa i.e. a transformation of thyroid tissue to lymphoid tissue.* MC inflammatory disorder of the thyroid and leading cause of hypothyroidism.Thyroid lymphoma is a rare but well recognized complicationPapillary thyroid carcinoma may be occasionally associated* Genetic association has been noted with HLA B8, DR3 and DR59.* More common in women (Male: female, 1:10), near menopause (30-50 years).Etiopathogenesis:* Autoimmune disease* Thought to be initiated by activation of CD4+T (helper) lymphocytes, which further recruit cytotoxic CD8+T cells.Hashimoto's Thyroiditis* Thyroid tissue is destroyed by cytrotoxic T cells and autoantibodies0.Autoantibodies are directed against1. Thyroglobulin (Tg): 60%2. Thyroid peroxidase (TPO): 95%3. TSH-R: 60%* It is also thought to be associated with:Increased intake of iodineDrugs such as interferon alpha, lithium, amiodaronePathology:* Gross examination: Mildly enlarged thyroid0 with pale, gray-tan cut surface* Microscopic examination:- Gland is diffusely infiltrated by small lymphocytes and plasma cellsQ and occasionally shows well-developed germinal centers.- Smaller thyroid follicles with reduced colloid and increased interstitial connective tissue.- Follicles are lined by Hiirthle or Askanazy cells0 (characterized by abundant eosinophilic, granular cytoplasm)Clinical Features:* MC presentation: Minimally or moderately enlarged firm gland0.* On examination an enlarged pyramidal lobe is often palpable.* Mild hyperthyroidism may be present initially (due to destruction of thyroid tissue)* Hypothyroidism is inevitable and usually permanent0.Laboratory findings:* Elevated TSH and presence of thyroid autoantibodies confirm the diagnosis0.* Elevated TSH. reduced T4 and T3 levels0.Presence to thyroid autoantibodies (particularly TPO antibody)0* In case of doubt, diagnosis is confirmed by F.NA biopsy.Management:* Thyroid hormone replacement therapy for overtly hypothyroid patients or in euthyroid patients to shrink large goiters.* Treatment is advised especially for middle-aged patients with cardiovascular risk factors such as hyperlipidemia or hypertension and in pregnant patients.* Surgery may occasionally be indicated for suspicion of malignancy or for goiters causing compressive symptoms or cosmetic deformity.