Answer: d) Anti-microsomal antibodyCHRONIC LYMPHOCYTIC or HASHIMOTO'S THYROIDITIS or NON GOITROUS or STRUMA LYMPHOMATOSAMost common cause of hypothyroidism in non-iodine deficiency regionsChronic autoimmune disorder with family history of autoimmune diseaseMC in women at menopausePainless enlargement of both lobes, which are firm, rubbery, firm and tenderPolymorphisms in immune regulation-associated genes, including cytotoxic T lymphocyte- associated antigen-4 (CTLA4) and protein tyrosine phosphatase-22 (PTPN22)Association with HLA DR 5 is seenMechanism of thyroid cell deathCD8+ cytotoxic T cell-mediated cell deathCytokine-mediated cell deathAutoantibodiesAnti microosomal antibodiesAnti thyroid peroxidase antibodiesAnti thyroglobulin antibodiesPathologyExtensive lymphocytic infiltration with germinal cells & epithelial hurthle cells(Askanazy cells)No colloid in the follicleMild hyperthyroidism present initially but hypothyroidism is inevitableOccasionally predisposes to papillary CA| risk of development of extranodal marginal zone B-cell lymphomas within the thyroid gland