What are the major causes of hypothyroidism?

Primary (chronic autoimmune thyroiditis, iatrogenic (thyroidectomy or radioiodine), iodine deficiency or excess, infiltrative diseases (hemochroma, sarcoidosis), congenital thyroid agenesis/dysgenesis, drugs (lithium/amiodarone/IFNa/IL2), transient hypothyroid)) Central hypothyroid (TSH def, TRH def) Generalized thyroid hormone resistane