De Quervain's Thyroiditis

De Quervain’s thyroiditis, also known as subacute granulomatous thyroiditis or giant cell thyroiditis, is a health condition involving the thyroid gland that usually resolves spontaneously without treatment. It is named after Fritz de Quervain.

Any individual may be affected, including both males and females of all ages. However, more women are affected than men with a ratio of approximately 4:1 and the highest incidence is observed in middle-aged people.

Cause

Although the precise cause is not known, De Quervain’s thyroiditis is believed to be caused by a viral infection and the inflammatory process associated with such infections. This is because many affected patients report having an upper respiratory tract infection within two months before the onset of symptoms. It is thought to be linked to viral infections such as Coxsackievirus, mumps, measles, and adenovirus.

There may also be other factors involved. In some studies, the incidence appears to be highest in summer, suggesting that seasonal variables may play a role in causing the condition. However, this is now clear from other studies.

Symptoms

The symptoms of De Quervian’s thyroiditis can be divided into four distinct stages, which typically progress over a period of up to six months. The phases are the acute phase (symptoms of hyperthyroidism), euthyroid phase (asymptomatic), hypothyroid phase, and recovery phase.

In the acute phase, which usually lasts from 3-6 weeks, patients will experience a period of hyperthyroidism, due to the failure of the colloid spaces cellular lining, which increases the circulation of colloid in the bloodstream. Symptoms during this period may include:

• Neck pain
• Tender diffuse goiter
• Tachycardia
• Sweating
• Heat intolerance
• Nervousness
• Frequent bowel movements
• Fever

The euthyroid phase is a transient phase without noticeable symptoms, which usually lasts from 1-3 weeks.

Following this, a period of hypothyroidism usually ensues due to a reduction in the production of thyroid stimulating hormone (TSH) in the pituitary gland. This phase lasts from several weeks to a chronic condition for some patients (approximately 10%). Symptoms in this phase may include:

• Fatigue
• Dry skin
• Swollen eyes
• Intolerance to cold
• Constipation

In the recovery phase, there is a depletion of the excess colloid and a resolution of symptoms.

Other symptoms associated with De Quervian’s thyroiditis may include painful dysphagia, fever, malaise, anorexia, and myopathy.

Diagnosis and Treatment

Accurate diagnosis of De Quervian’s thyroiditis is important because, unlike other conditions that cause symptoms of hyperthyroidism, it resolves spontaneously without the need for a specific treatment. Therefore, it should be distinguished from other similar condition so that unnecessary treatments, such as anti-thyroid medications or thyroid replacement therapy, are not prescribed.

On histology, multi-nucleated giant cells are evident, which gives reason to the alternative name of giant cell thyroiditis. In some cases, thyroid antibodies may be present.

In some cases, the combination of a beta-blocker medication with a non-steroidal anti-inflammatory drug (NSAID) can be useful to reduce symptoms. If this treatment is not effective to reduce inflammation, the NSAID can be substituted for a corticosteroid medication.

Epidemiology

According to the one epidemiological study in Minnesota, there were 94 patients identified with De Quervain’s thyroiditis. This represents an incidence of 12.1 cases per 100,000 people per year. There was a lower incidence in males than females, ranging from 4.1 to 19.1 cases per 100,000 people per year. The highest incidence is seen in middle-aged people with 35 cases per 100,000 people per year.

References

• http://emedicine.medscape.com/article/125648-overview#showall
• http://thyrosite.com/course%20book/de%20quervain
• http://www.uptodate.com/contents/subacute-thyroiditis
• http://www.thyroidmanager.org/chapter/acute-and-subacute-and-riedels-thyroiditis/
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4453108/