Diffuse or nodular goiter caused by various factors, without significant abnormalities in thyroid hormone secretion. It can be endemic (endemic goiter) or sporadic (sporadic goiter). Disease causes include: 1. Iodine deficiency: Insufficient iodine intake or increased iodine demand; long-term excessive iodine intake can also hinder iodine organification and lead to goiter. 2. Goitrogenic substances: Such as excessive consumption of foods that inhibit thyroid hormone synthesis (cabbage, radish, onion, soy products) and medications (e.g., thiourea, sulfonamides, lithium, cobalt, perchlorate, para-aminosalicylic acid, iodine-containing drugs, etc.). 3. Hereditary thyroid hormone synthesis disorders.

bubble_chart Diagnosis

1. Medical History and Symptoms:

Often no specific symptoms, only mild to grade II thyroid enlargement. In the late stage [third stage], multiple nodules form, and the thyroid texture becomes harder as the disease progresses. Adolescent goiter may fluctuate spontaneously with emotions, climate, and menstruation cycles. Nodular goiter may suddenly enlarge and become painful due to nodule hemorrhage or necrosis.

2. Physical Examination Findings:

Apart from thyroid enlargement, no other positive findings are detected during the physical exam.

3. Auxiliary Examinations:

1. Thyroid hormone and TSH levels are generally normal, though some iodine-deficient patients may have low T4. Thyroid iodine uptake is often elevated, but the T3 suppression test is normal. In a few cases with autonomous functional nodules, TSH may be low, and the TRH stimulation test shows a reduced response. 2. Thyroid isotope scanning may reveal diffuse thyroid enlargement. Nodules with cystic changes appear as "cold nodules," while autonomous functional nodules show "heat accumulation nodules."

In cases of hemorrhage within a simple goiter nodule, scanning may show a cold nodule, which can be misdiagnosed as subacute thyroiditis or stony goiter (thyroid carcinoma). A thyroid needle biopsy should be performed. Additionally, it should be differentiated from Hashimoto's thyroiditis, which often shows significantly elevated thyroglobulin antibodies and microsomal antibodies.

bubble_chart Treatment Measures

1. Oral administration of small to moderate doses of thyroid tablets (20–60 mg/d) or levothyroxine tablets (50–150 μg/d) can help shrink the thyroid gland, but it may not be effective for long-standing cases. Replacement therapy should be carefully monitored to avoid drug-induced hyperthyroidism due to excessive dosage.

2. For cases caused by iodine deficiency, iodine supplementation is necessary. However, excessive iodine can inhibit thyroid hormone synthesis, elevate TSH levels, enlarge the goiter, and even induce iodine-induced hyperthyroidism.

3. Surgical treatment: Indicated for patients with significant thyroid enlargement causing compressive symptoms, nodules that enlarge despite thyroid hormone replacement therapy and are suspected of malignancy, or those with autonomous functional nodules. Postoperatively, thyroid preparations should be routinely administered to prevent recurrence.