胃食管反流病（GERD）患者指南

Overview

Hashimoto's thyroiditis (also called Hashimoto's disease or chronic lymphocytic thyroiditis) is an autoimmune disorder. Your immune system mistakenly attacks the thyroid gland, a small butterfly-shaped organ at the base of your neck that produces hormones controlling metabolism, energy, heart rate, and body temperature. Over time this inflammation damages thyroid tissue and reduces hormone production, leading to hypothyroidism (underactive thyroid).

It is the most common cause of hypothyroidism in iodine-sufficient countries and occurs far more often in women than men. The condition develops gradually and is lifelong, but with proper treatment most people manage it successfully and maintain good quality of life.

Signs & Symptoms

Early on, many people have no noticeable symptoms. As thyroid function declines, signs of hypothyroidism appear. Symptoms can develop slowly over months or years and may be mistaken for normal aging, stress, or other conditions.

• Fatigue and low energy that does not improve with rest
• Unexplained weight gain or difficulty losing weight
• Increased sensitivity to cold
• Dry skin, thinning hair, or brittle nails
• Constipation
• Muscle weakness, aches, or joint pain
• Puffy face, especially around the eyes
• Hoarse voice or enlarged thyroid (goiter) that may feel like fullness in the neck
• Heavy or irregular menstrual periods
• Depression, memory problems, or 'brain fog'
• Slow heart rate

Causes & Risk Factors

The exact trigger is unknown, but Hashimoto's involves a combination of genetic predisposition and environmental factors that cause the immune system to produce antibodies (especially thyroid peroxidase antibodies, or TPOAb) that attack thyroid cells. Chronic inflammation gradually destroys the gland's ability to make enough thyroid hormone.

• Being female (women are 5–10 times more likely to develop it)
• Middle age (most common between 30 and 50, though it can occur at any age)
• Family history of Hashimoto's or other autoimmune diseases
• Other autoimmune conditions such as type 1 diabetes, rheumatoid arthritis, celiac disease, or lupus
• Excessive iodine intake or certain medications in susceptible people
• Pregnancy or postpartum period (can trigger or unmask the condition)
• Radiation exposure to the neck

Diagnosis

Diagnosis begins with a medical history and physical exam (checking for goiter or other signs). Blood tests confirm the condition. Your doctor will typically order thyroid-stimulating hormone (TSH), free thyroxine (free T4), and thyroid antibody tests (TPO antibodies are elevated in most people with Hashimoto's).

• Elevated TSH with low or normal free T4 indicates hypothyroidism
• Positive TPO antibodies support the diagnosis of Hashimoto's even if thyroid function is still normal (early stage)
• Ultrasound may be used to evaluate goiter size or rule out nodules
• Rarely, a biopsy is needed if a nodule looks suspicious

Treatment & Management

There is no cure that stops the autoimmune process, but treatment focuses on replacing the missing thyroid hormone so your body functions normally. The standard medicine is levothyroxine, a synthetic form of T4 taken once daily on an empty stomach. Dose is individualized based on blood tests, age, weight, and other factors, and is adjusted until TSH is in the target range.

Most people need lifelong daily medication. Regular follow-up blood tests (every 6–12 months once stable, more often when starting or changing dose) ensure the dose remains correct. Some people with mild early disease and normal hormone levels may only need monitoring until hypothyroidism develops. Surgery is rarely required unless a large goiter causes compression symptoms.

Living With It

With consistent treatment and follow-up, most people with Hashimoto's live normal, healthy lives. Focus on taking medicine correctly, attending appointments, and supporting overall health. Some people notice that stress, illness, or poor sleep can temporarily worsen fatigue even when labs are normal. Work with your healthcare team; do not stop or change medicine on your own.