Could a Hives Rash Be a Sign of Thyroid Disease?

Identifying the Relationship between Recurring Hives and Thyroid Disorders

Sometimes an itch is just an itch. But when that itch starts with the sudden appearance of raised skin rashes it is known as urticaria, or more commonly hives. When these hives appear without any apparent cause like food or pollen allergy, insect bites, or chemical exposures, they are said to be spontaneous. Spontaneous hives lasting for more than 6 weeks (also known as chronic)  might hint at an underlying health problem like an autoimmune disease. Autoimmune diseases are conditions where the body’s immune system mistakenly attacks one or more of its organs. More than half of the people living with chronic spontaneous urticaria (or CSU for short) may also grapple with an autoimmune disorder that affects their thyroid gland (Gonzalez-Diaz et al., 2020)).

CSU is common among people grappling with Hashimoto's thyroiditis, an autoimmune disease that leads to hypothyroidism (González-Díaz et al., 2020). Let's explore further the connection between CSU and thyroid disease, shedding light on relevant symptoms, tests, and treatments crucial for managing this recurring skin condition.

Deconstructing the Link: Autoimmune Thyroid Disease and Hives

In autoimmune disorders, the body's immune system mistakenly attacks its own cells and tissues, leading to cascades of repetitive assaults known as flares. In autoimmune thyroid disorders, the thyroid gland becomes the target. In this case, the immune response churns our autoantibodies targeting receptors in the thyroid gland, resulting in its destruction, and may subsequently lead to hypothyroidism (an underactive thyroid) or hyperthyroidism (an overactive thyroid). This same immune response’s autoantibodies also target a specific receptor found in tissues under the skin. This triggers the production of a protein called immunoglobulin E (IgE), which kickstarts the allergic response chain, leading to hives (Goh et al., 2009) (). Like hives due to other causes, those associated with thyroid disease tend to develop suddenly and can show up anywhere on the body. While most hive cases resolve within a few days to weeks, hives from an autoimmune thyroid disorder usually stay for over six weeks and often recur. CSU sometimes results in skin-coloured or reddish elevated patches (wheals) that alter in shape and size, disappearing temporarily only to reappear later. These patches often induce itching, ranging from mild to severe, and might manifest a stinging or burning sensation.

Battling with Hashimoto's

Hashimoto's thyroiditis stands as the most common form of autoimmune thyroid disease. CSU may appear simultaneously with an autoimmune flare, or even when the disease is subclinical, that is, active but not displaying noticeable symptoms. Even during these subclinical phases, low levels of autoantibodies can trigger an IgE response. However, not all Hashimoto's sufferers will experience CSU, suggesting that other factors play a role.

Graves' Disease Intricacies

In some cases, hives have been associated with Graves' disease, where the immune system’s attack on the thyroid gland leads to an overproduction of thyroid hormone. Despite studies, the specific mechanism linking hives and hyperthyroidism remains unclear and requires further research (Ruggeri et al., 2013).

Emerging Autoimmune Culprits

CSU has also been linked to alternate forms of autoimmune thyroid conditions, including painless thyroiditis, subacute thyroiditis, and postpartum thyroiditis.

Skin Signposts to Thyroid Disease

Thyroid disease can substantiate its presence through other skin symptoms, such as pretibial myxedema associated with Hashimoto's and Graves' disease, which results in pinkish or purplish nodules on the lower legs or feet due to hyaluronic acid deposits under the skin.

Moreover, hypothyroidism can cause skin discolouration, cold extremities, coarse and dry texture, and skin cracking. Conditions inducing hyperthyroidism can herald face flushing and reddened or overly sweating palms, culminating in thin, soft, and sometimes glossy skin.

Medical Intervention: When to Seek Help

While most hives are self-limited and non-severe, it's advisable to seek medical advice if your rash is persistent or suspected to be linked to a thyroid condition. In severe cases, sudden hives could point to anaphylaxis, a severe body-wide allergic reaction that could lead to shock, coma, or even death if untreated.

Diagnosing and Dealing with Chronic Spontaneous Urticaria 

When it comes to diagnosing chronic hives as spontaneous, it's crucial to first exclude common triggers. Potential triggers include food allergies, cold or sunlight exposure, stress, exercise, skin pressure, and scratching (Rumbyrt, Katz & Schocket, 1995). Blood tests, skin biopsies, skin-prick tests, and food challenges may be required to exclude infections or inflammatory conditions and specific allergy or food intolerance types. When chronic hives are thought to be spontaneous, an autoimmune disease work-up may be necessary. If autoimmune thyroid disease is suspected, tests including an autologous skin serum test, thyroid hormone tests, and autoimmune thyroid tests may help validate the diagnosis (Rumbyrt, Katz & Schocket, 1995).

Decoding the Solution to a Thyroid Rash

The onset of hives may or may not require treatment, depending on its severity and persistence. Treatment aims to provide symptom relief and prevent any recurrence. A comprehensive plan to subdue hives might include evading trigger factors, utilizing topical anti-itch creams, administering oral antihistamines, and employing thyroid hormone replacement like Levothyroxine. This synthetic thyroid hormone, historically employed to manage hypothyroidism, may not solve the underlying autoimmunity leading to Hashimoto's thyroiditis but can regulate hormone levels, reducing the likelihood of hypothyroid symptoms and may also help reduce itching in CSU (Najafipour et al., 2018).

Recap

Hives are itchy bumps on the skin which generally resolve within a few days or weeks. However, when hives persist over six weeks or frequently recur, it might signal an autoimmune disorder like Hashimoto's thyroiditis.

While hives can be alleviated using anti-itch creams and oral antihistamines, the presence of an autoimmune thyroid disease might necessitate a synthetic thyroid hormone like levothyroxine to help manage the hypothyroid symptoms and possibly also reduce itching. 

Eureka provides complimentary recommendations to boost your thyroid well-being. Stay tuned for practical tips on maintaining optimal thyroid health!

References

1. Chronic Urticaria and Thyroid Autoimmunity: This study explores the significant association between chronic urticaria and thyroid autoimmunity, suggesting a potential autoimmune mechanism in some patients with chronic idiopathic urticaria (Gonzalez-Diaz et al., 2020) 
2. Chronic Urticaria and the role of autoimmunity: This is a medical review that highlights the role of IgE in the development of chronic autoimmune urticaria (Goh et al., 2009). 
3. Chronic Urticaria and Thyroid Autoimmunity: A comprehensive review on the frequent co-occurrence of chronic urticaria and thyroid autoimmunity, examining the implications for diagnosis and management of both conditions (Rumbyrt, Katz, & Schocket, 1995).
4. Link Between Chronic Urticaria and Autoimmune Thyroid Disease: This paper reviews the link between chronic urticaria and autoimmune thyroid disease, specifically Grave’s disease(Ruggeri et al., 2013).
5. Effect of Thyroid Treatment on Urticaria: Study on the effect of levothyroxine treatment in patients with chronic urticaria and thyroid autoimmunity, noting some cases of symptom resolution (Najafipour et al., 2018).