1. NYU Medical Grand Rounds Clinical Vignette Arnab Ghosh, MD PGY-2 10/23/12 U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

2. The patient is a 67 year old male who presented to his primary care physician with palpitations. Chief Complaint U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

3. When reviewed in clinic by his primary physician, he appeared clinically euthyroid although he did have evidence of an enlarged thyroid gland on examination by his primary care physician. He was referred to an endocrinologist. History of Present Illness U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

4. Additional History Past Medical History: Nil Past Surgical History: Nil Social History: Works as a dentist, occasional social drinker, non smoker, nil illicit drug use Family History: Nil family history of thyroid disease Medications: Nil U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

5. Physical Examination General: He appeared well Thyroid Examination: a palpable thyroid approximately one and a half times the normal size Nil evidence of tenderness, dominant nodules nor lymphadenopathy Nil peripheral stigmata of thyroid disease Remainder of Physical Exam was normal U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

6. Laboratory Findings CBC: within normal limits Basic Metabolic panel: within normal limits Hepatic panel: within normal limits Thyroid Stimulating Hormone (TSH) 2.7 miU/L (N:0.4-4.0 mIU/L) T4 5.9 mcg/dL (N: 4.8-11.0 mcg/dL) T3 0.78 ng/mL (N:0.8-1.7 ng/mL) Anti-thyroglobulin antibody: 2.4 U/mL (>1.0 U/mL – positive) Anti-thyroperoxidase antibody:14.0 U/mL (>1 U/mL – positive) U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

7. Other Studies ECG: normal sinus rhythm with occasional premature ventricular contractions Thyroid Ultrasound: 1.7x1.1cm nodule in the R lobe (hypoechoic) 9x11mm nodule in R lobe (hypoechoic) Nil microcalcifications, nil increased vascularity Fine Needle Aspiration performed of larger nodule: Colloid in a population of lymphocytes U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

8. Euthyroid lymphocytic thyroiditis Working Diagnosis U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

9. The patient was referred back to his primary care physician, who intermittently checked TSH levels, which remained normal 8 years later, the patient was referred back to his endocrinologist with a TSH measured at 4.16 mIU/L (N:0.4-4.0mIU/L) Patient was clinically euthyroid during this time Outpatient Course U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

10. On repeat labs by the endocrinologist, the TSH was measured 11.4 mIU/L Other laboratory values of note: –T4 6.3 mcg/dL (N: 4.8 - 11.0 mcg/dL) –T3 Uptake 31.7% (N: 23.5 - 40.6%) –Free thyroid index 4.0 (N: 1.5 - 3.8) –Anti-thyroperoxidase antibody: 239 IU/mL (normal < 27 iU/mL) –Anti-Thyroglobulin antibody: < 20 IU/mL (normal) Outpatient Course U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

11. Repeat Thyroid Ultrasound performed: Coarsely and diffusely multinodular Mild hyperaemia of the entire thyroid R lobe: 2 solid hypoechoic nodules, 15x10mm and 9x9mm L inferior lobe: 8x6mm nodule Nil calcifications Fine Needle Aspiration of 3 nodules: R and L nodules: colloid with lymphocyte background L inferior lower lobe: colloid accumulation Outpatient Course U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

12. The patient was started on Levothyroxine 25 μmcg daily by mouth Outpatient Course U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

13. Repeat lab values 3 months later in clinic –TSH 2.74 miU/L (N:0.4-4.0 mIU/L) –T4 5.7 mcg/dL (N: 4.8 - 11.0 mcg/dL) –T3 Uptake 33.9% (N: 23.5 - 40.6%) –Free thyroid index 1.9 (N: 1.5 - 3.8) Outpatient Course U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS

14. Hashimoto’s thyroiditis (with failing thyroid) Final Diagnosis U NITED S TATES D EPARTMENT OF V ETERANS A FFAIRS