In addition to the varieties of thyroiditis, which are inflammatory diseases specifically involving the thyroid gland, generalized or systemic diseases may also involve the thyroid gland. Sarcoidosis may involve the thyroid, and amyloid may be deposited in the gland in quantities sufficient to cause goiter. In all of these diseases, it may be necessary to give the patient levothyroxine replacement therapy if the function of the gland has been impaired. The lesions of sarcoid may appear in the thyroid gland in 1–4% of patients with systemic sarcoidosis. Thyroid dysfunction was infrequently (1–3%) reported in systemic sarcoidosis, but reached 26% in patients with cutaneous sarcoidosis. Multinodular goiter has been described as an initial presenting manifestation in a woman eventually diagnosed with systemic sarcoidosis. Deposits of amyloid are quite common in systemic amyloidosis, but this uncommonly causes goiter. Localized primary amyloidosis presenting with isolated amyloid goiter is also rarely encountered. Clinically, an amyloid goiter may be progressive, diffuse, and rapidly lead to compressive symptoms. Thyroid function in association with an amyloid goiter is normal in two-thirds of cases. In addition to the focal deposition of amyloid in thyroid tissues associated with most cases of medullary thyroid carcinoma, several cases of papillary thyroid carcinoma have been reported in association with amyloid goiter. Amyloid goiter may be readily diagnosed by fine-needle aspiration biopsy and has been reported in conjunction with infiltration of other endocrine organs such as the pituitary. Some patients may require surgery to relieve the compressive symptoms or for a confirmatory diagnosis. Other rare causes of chronic thyroiditis include post-partum thyroiditis, drug-induced thyroiditis, and focal lymphocytic thyroiditis.