The main symptom of chronic hives is recurring episodes of itchy, red hives over large areas of the body plus swelling (edema). Many people find it hard to get an accurate diagnosis when they first develop chronic hives. This is partly because chronic hives are rare and many other conditions cause similar skin symptoms.
Your doctor may have to perform many tests to reach a proper diagnosis. Meantime, it is not uncommon for people with chronic hives to be misdiagnosed with many other conditions.
Some common misdiagnosis may include:1-11
- Urticarial vasculitis
- Lupus
- Cryoglobulinemia
- Schnitzler syndrome
- Mastocytosis
- Polymorphic eruption of pregnancy
- Hypereosinophilic syndrome
- Cryopyrin-associated periodic syndromes
Urticarial vasculitis
Urticarial vasculitis is a condition where inflammation of blood vessels blocks blood flow. This can damage certain organs. It usually affects small blood vessels in the skin and causes patches of red hives.1
Urticarial vasculitis has slightly different symptoms than chronic hives. Doctors may suspect urticarial vasculitis if:2,3
- Hives are more painful than itchy
- Hives last longer than 48 hours
- Hives leave bruising or skin discoloration
- You also have fever, chills, joint pain, or other symptoms
If your doctor suspects urticarial vasculitis, they will order a skin biopsy. This will help them see if you have inflammation and damage to blood vessels.2
Systemic lupus erythematosus (lupus)
Lupus is the most common type of lupus. It is an autoimmune condition, which means your immune system mistakenly attacks healthy cells. This causes inflammation that damages many different organs. Symptoms vary for each person but often includes episodes of hives.4,5
People with lupus usually have other symptoms that distinguish it from chronic hives, such as:2,3
- Fever and fatigue
- Weight loss
- Joint inflammation or pain
- Kidney, lung, or heart problems
- Sun sensitivity
If your doctor suspects SLE based on your symptoms, they may perform certain tests. These include blood and urine tests to look at inflammation and organ function.2
Cryoglobulinemia
Cryoglobulinemia is a type of blood vessel inflammation. It is often linked to hepatitis C infections. In cryoglobulinemia, abnormal blood proteins (cryoglobulins) clump together at cold temperatures. This restricts blood flow and causes damage to many organs.6
People with cryoglobulinemia may not have symptoms. However, when symptoms do occur, they usually include a skin rash or hives. Symptoms that differ from chronic hives include:2
- Joint or muscle pain
- Severe fatigue
- Discoloration of hands in cold temperatures
- Numbness, tingling, or burning sensation of hands and feet
If your doctor suspects cryoglobulinemia based on your symptoms, they can perform certain tests. This includes a biopsy of skin or other organs. It also may include blood tests for cryoglobulin proteins.2
Schnitzler syndrome
Schnitzler syndrome is a rare condition. It causes recurring episodes of inflammation because of problems with your immune system.7
People with Schnitzler syndrome have a chronic red rash that looks similar to hives. They also have high levels of a protein called immunoglobulin M (IgM) in the blood. Symptoms that differ from chronic hives include:2,3
- Fever
- Weight loss
- Joint inflammation or pain
- Enlarged lymph nodes, liver, or spleen
Mastocytosis
Mastocytosis is a condition caused by a buildup of mast cells. These are white blood cells involved in allergic reactions. A buildup of mast cells under the skin and other organs causes a range of symptoms. There are 2 types of mastocytosis:8
- Cutaneous mastocytosis – Affects only the skin and causes red itchy hives; occurs mostly in children
- Systemic mastocytosis – Affects multiple parts of the body; occurs mostly in adults
In mastocytosis, hives usually happen with other recurring symptoms. However, hives usually do not occur as often as they do in chronic hives.2
Polymorphic eruption of pregnancy (PEP)
PEP is an itchy rash that affects pregnant women. It usually starts in the last 3 months of pregnancy and goes away after delivery. The rash usually starts in stretch marks on the abdomen and then spreads to the buttocks, thighs, arms, and legs.9
Doctors usually diagnose PEP using health history and symptom description. Symptoms are usually controlled using moisturizers, antihistamines, and topical steroids.2
Hypereosinophilic syndrome (HES)
HES is a group of conditions with high levels of eosinophils. Eosinophils are white blood cells that play an important role in your immune system. Over time, the excess eosinophils enter various tissues and damage your organs.10
A common symptom of HES is recurring hives and swelling. Other symptoms include fatigue, cough, and shortness of breath. Diagnosis includes blood tests for eosinophil levels. It also includes other tests to identify possible causes.2
Cryopyrin-associated periodic syndromes (CAPS)
CAPS includes a number of very rare autoinflammatory conditions, including:2,3
- Familial cold autoinflammatory syndrome (FCAS)
- Muckle-Wells syndrome (MWS)
- Neonatal-onset multisystem inflammatory disorder (NOMID)
Recurring episodes of hives is a common symptom of these conditions. Doctors will diagnose CAPS based on symptom descriptions, family history, and lab tests.2
Other possible diagnoses
For some people with chronic hives, swelling under the skin (angioedema) is the only or main symptom. Many conditions cause symptoms that look like angioedema. Examples of these differential diagnoses include:11
- Contact dermatitis
- Autoimmune conditions
- Eyelid edema
- Parasitic infections
- Hypothyroidism
- Idiopathic edema
- Factitious angioedema