What are the other Names for this Condition? (Also known as/Synonyms)

• Chronic Physical Urticaria
• Urticaria, Chronic Inducible type

What is Chronic Inducible Urticaria? (Definition/Background Information)

• Urticaria is a common inflammatory condition of skin that results in weals (red skin sign with itching) and/or angioedema (swelling due to fluid accumulation). It is seen in individuals of a wide age group and may be described as acute or chronic, based on the duration of the signs and symptoms
• Chronic urticaria is a skin condition that usually lasts over 6 weeks. The signs and symptoms are observed for a long-term; daily or periodic occurrence of weals may be noted
• Chronic Inducible Urticaria (or Chronic Physical Urticaria) is a form of chronic urticaria that occurs following a known trigger. It may be of several types based on the specific physical stimulus. In this type, the signs and symptoms usually occur within a few minutes of the stimuli
• Based on the known triggers of Chronic Inducible Urticaria, it constitutes the following types:
  • Aquagenic urticaria
  • Cholinergic urticaria
  • Cold urticaria
  • Contact urticaria
  • Exercise-induced urticaria
  • Heat urticaria
  • Pressure urticaria or delayed pressure urticaria
  • Solar urticaria or light urticaria
  • Symptomatic dermographism or urticaria factitia
  • Vibration-induced urticaria or vibratory urticaria
• Thus, Chronic Inducible Urticaria may be triggered by a variety of factors that include physical contact with certain substances, chronic pressure on skin, sweat-induced exercise, hot or cold air/water, exposure to sun, vibrations, etc.
• Any region of body skin may be affected; although, the skin symptoms appear in the region where the stimulus occurs. Intense itching may lead to skin ulceration and scarring, which can cause emotional stress from cosmetic concerns. The skin rashes can be localized or widespread
• Chronic Inducible Urticaria is treated symptomatically and based on the triggering factor. The treatment may involve controlling the trigger, use of topical ointments and creams, antihistamines, and immunosuppressive medication for severe signs and symptoms. The prognosis with adequate treatment is usually good, although the condition may recur

Who gets Chronic Inducible Urticaria? (Age and Sex Distribution)

• Chronic Inducible Urticaria can affect both children and adults, though it is more often seen in adults
• Both males and females are affected
• There is no race or ethnic preference observed

What are the Risk Factors for Chronic Inducible Urticaria? (Predisposing Factors)

The risk factors for Chronic Inducible Urticaria include:

• Use of tight clothing, sports gear, protective clothing, etc.
• Pressure on the skin that occurs from wearing tight clothing, helmet, or safety belt
• Scratching or rubbing the skin (such as while drying with a towel)
• Exposure to hot or cold substances
• Exposure to ultraviolet light
• Physical exercise
• Exposure to allergens including insects, plants, certain foods, cosmetics, etc.
• Vibrations from heavy equipment
• Contact with chlorinated water

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Chronic Inducible Urticaria? (Etiology)

Urticaria can be caused by a variety of factors. The condition develops due to the release of chemical substances, such as histamines, platelet activating factor, and cytokines (example bradykinin), from inflammatory cells called mast cells and basophils.

• Chronic urticaria may be caused by an underlying infection, through hypersensitivity on exposure to certain substances causing an allergic reaction, or due to body’s immune system attacking one’s own body
• Chronic Inducible Urticaria (or Chronic Physical Urticaria): It occurs following a known trigger and may be of several types based on the specific and physical stimulus (such as pressure, exposure to sunlight, heat, or cold, contact, vibrations, etc.)

What are the Signs and Symptoms of Chronic Inducible Urticaria?

The signs and symptoms of Chronic Inducible Urticaria may be mild or severe, localized or diffuse (and sometimes, extensive), and can vary from one individual to another. It also depends on the type of stimulus causing the physical reaction in the body.

The signs and symptoms of Chronic Inducible Urticaria that occur within a few minutes of stimuli exposure may include the following:

• Initially, localized itching of skin may be observed; the skin may appear swollen
• Formation of skin rashes or weals (wheals) that are associated with redness (or pinkish discoloration) and intense itching
• The skin surrounding the affected area (weal) may be normal skin color or appear red (erythema)
• The weals may change in shape and size; weals may be spherical, arranged in a random form, or ring-like pattern
• The symptoms are usually located in the region where the stimulus occurs. Thus, the affected skin may take the shape and pattern of the contact area of the trigger (such as the impression of a seat belt or tight clothing)
• Depending on the type of stimuli, the condition can be localized or widespread or extensive
• In some individuals, there may be a burning sensation accompanying itching
• Individual weals may vary in size from a few mm to few cm; but, numerous weals covering a large area of the body skin may be observed
• The weals may last for several minutes to up to a day; few cases are non-itchy
• In some cases, it can lead to hyperpigmentation (increased skin pigmentation) or hypopigmentation (decreased skin pigmentation)
• When pressure is applied on the hives, it blanches (becomes pale or white in color)
• Scratching can result in worsening of the symptoms and lead to further skin complications such as ulceration and secondary infections
• Angioedema: It may or may not occur with chronic urticaria
  • Angioedema is swelling due to fluid accumulation in the mucus membranes or deep within the skin. This lasts for up to 3 days, it can be also itchy
  • Angioedema usually occurs focally; most common sites are the head and neck region, hands, feet, and genitalia. In the head and neck region, it can involve the eyelids, lips, oral cavity, or larynx
• Pain, pain on touch

How is Chronic Inducible Urticaria Diagnosed?

A diagnosis of Chronic Inducible Urticaria may involve the following tests and examinations:

• Physical examination of  the skin and medical history evaluation
• Skin allergy test
• Radioallergosorbent (RAS) test; to determine the specific allergy-causing substance 
• Blood test to detect various antibodies against allergens including:
  • Complete blood count (CBC) including eosinophil count since, there may be increased number of eosinophils (peripheral eosinophilia)
  • Antinuclear antibody (ANA) test
  • Erythrocyte sedimentation rate (ESR) test
  • Immunoglobulin E (IgE) levels in blood
  • Serum level of complement
  • Serum C-reactive protein blood test
• Tests to rule-out other underlying autoimmune conditions and infections (if necessary)
• Physical hot and/or cold provocation test
• Skin biopsy: A skin biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis

The healthcare provider may induce symptoms by administering the triggers in a controlled fashion. This procedure is performed under close medical supervision, either in an out-patient healthcare setting, or as an in-patient setting in a hospital. Since, potentially life-threatening symptoms may develop during this procedure, access to emergency medical resources is generally warranted. Hence, such testing should not be performed at home.

A differential diagnosis may be considered to eliminate certain skin conditions, prior to arriving at a definitive diagnosis. The following conditions may be considered:

• Chronic itching due to a variety of other causes
• Contact dermatitis
• Dermatitis herpetiformis
• Drug eruptions of skin
• Eczema
• Erythema multiforme
• Insect bites
• Pemphigoid
• Pityriasis rosea
• Polymorphous eruption of pregnancy
• Urticarial vasculitis
• Familial cold autoinflammatory syndrome (FACS)

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Chronic Inducible Urticaria?

The following complications of Chronic Inducible Urticaria may be noted:

• Intense scratching may result in skin scarring
• Itching can lead to ulceration of skin, causing superimposed bacterial and fungal skin infections
• Severe cases can cause disruption in sleep 
• Cosmetic concerns leading to stress
• Frequent episodes of urticaria can affect the quality of life, which can result in severe stress. This severe stress can in-turn be a trigger for further worsening of the condition
• Involvement of the larynx due to angioedema, may be life-threatening and a medical emergency. If the larynx is involved, it can result in sudden breathing difficulties, due to laryngeal edema
• Severe chronic urticaria can result in anaphylactic shock, which is a potentially life-threatening medical condition
• Those with aquagenic and cold urticaria must use due caution when entering swimming pools

How is Chronic Inducible Urticaria Treated?

The treatment depends upon the severity of the signs and symptoms and the type of Chronic Inducible Urticaria. It primarily includes the avoidance of known triggers. The treatment may be specific to the particular trigger causing the symptoms. In severe cases, an allergy specialist may be consulted.

The treatment measures for Chronic Inducible Urticaria include:

• Cooling the skin using moist towels
• Topical steroid treatment that may include moisturizing creams to soothe the condition
• Systemic steroids
• Anti-histamine therapy, both non-sedating and sedating types
• Immunosuppression therapy for severe symptoms: Use of immune modulators or medications that modulate immunity
• Patient education in understanding the condition is beneficial
• Stress management for severe and chronic conditions

How can Chronic Inducible Urticaria be Prevented?

Although Chronic Inducible Urticaria may not be prevented, further and future flare-ups may be avoided, if the triggers that cause the condition are known and recognized. In such cases, the following may be considered:

• Appropriately treating acute urticaria
• Avoiding the use of materials or substances that cause Chronic Inducible Urticaria
• Informing the healthcare provider suitably of any food, drug, or contrast material allergies (if these are identified earlier)

What is the Prognosis of Chronic Inducible Urticaria? (Outcomes/Resolutions)

• The prognosis of Chronic Inducible Urticaria is generally good with suitable treatment and stoppage of the triggering substance or factor. However, the condition is known to recur in some individuals
• Anaphylactic reaction/shock can be fatal without treatment

Additional and Relevant Useful Information for Chronic Inducible Urticaria:

Please visit our Skin Care Health Center for more physician-approved health information:

http://www.dovemed.com/healthy-living/skin-disorders/