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

• Giant Urticaria
• Persistent Insect Bite Reaction
• Quincke Syndrome

What is Papular Urticaria? (Definition/Background Information)

• Papular Urticaria is described as an allergic skin reaction to insect bites and stings that results in the presence of itchy red rashes. It is commonly observed in young children, and the source of bites/stings could be mites, fleas, or mosquitoes
• Despite the name, Papular Urticaria is not classified as a “true urticaria”, which is a common inflammatory condition of skin that results in weals (reddish and itchy skin spots) and/or angioedema (swelling due to fluid accumulation)
• Papular Urticaria normally tend to resolve spontaneously, although the risk for recurrence is generally high. Topical steroids and antihistamine therapy may be recommended by the healthcare provider to improve the signs and symptoms. In a vast majority of cases, children tend to outgrow this allergic condition (i.e., they may get sensitized to it)

Who gets Papular Urticaria? (Age and Sex Distribution)

• Papular Urticaria is generally observed in children between 2 and 10 years of age. However, it may be observed in a wider age range too
• Both males and females are affected
• Worldwide, there is no racial or ethnic preference observed. But, most of the cases are reported during spring and summer

What are the Risk Factors for Papular Urticaria? (Predisposing Factors)

The risk factors for Papular Urticaria include:

• Bites and stings caused by a variety of insects and arachnids such as the following:
  • Bed bugs
  • Beetles
  • Caterpillars
  • Fleas
  • Gnats
  • Mites
  • Mosquitoes
  • Ticks
• Young children have a high risk due to a lack of desensitization to insect bites or stings. Desensitization indicates a tolerance to the allergy caused by an insect bite/drug/cosmetic by normalizing the body’s adverse reaction to such a stimulus
• Visitors or travelers to a new location
• Contact with pets, such as dogs and cats, is the single-most important risk factor for insect bites

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 Papular Urticaria? (Etiology)

• Papular Urticaria is caused from insect bites/stings and is believed to be an abnormal cell-mediated immune response (allergic reaction) on the skin
• In children (mostly), who have not become desensitized to insect bites, the bite sets off an allergic reaction. However, after a period of time (months and years) and following several bites, the tolerance level of the individual increases, thereby reducing the incidence of Papular Urticaria

The condition does not spread from one individual to another through physical contact or through sharing of items. It is a non-infectious condition.

What are the Signs and Symptoms of Papular Urticaria?

The signs and symptoms of Papular Urticaria may vary from one individual to another, but may include:

• Presence of itchy red skin bumps (papules) on the body; some lesions appear as blisters
• The size of the lesions may be between 2 to 20 mm
• Symmetrically distributed collection of bumps or blisters over the body
• Intense itching may provoke scratching that can cause the blisters to break, ooze, and form crusts
• The lesions may ‘come and go’; new lesions may be noted from repeat insect bites, just as old lesions are healing
• The bumps and blisters may resolve over weeks and months
• Areas of light/dark pigmentation may be noted at the site of the lesions following its resolution, particularly if the lesions were scratched

How is Papular Urticaria Diagnosed?

A diagnosis of Papular Urticaria may involve the following exams and procedures:

• Physical examination of the individual and medical history evaluation
• Blood tests, analysis of pus, and culture of the fluid being drained, as needed
• Skin prick (allergy) test
• Dermoscopy: Dermoscopy is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• Skin biopsy: A skin tissue 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

A differential diagnosis is important to exclude other conditions presenting similar signs and symptoms. These include:

• Atopic dermatitis
• Id reaction
• Lymphomatoid papulosis
• Pityriasis lichenoides
• Prurigo types
• Scabies

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 Papular Urticaria?

The possible complications due to Papular Urticaria include:

• Emotional stress due to cosmetic issues
• Superimposed bacterial and fungal skin infections
• Cellulitis
• Septicemia, in rare cases
• Cutaneous vasculitis
• Scarring on healing
• Recurrence of the condition
• Treatment complications

How is Papular Urticaria Treated?

The treatment measures available for Papular Urticaria include:

• Calamine lotions and menthol creams
• Use of topical steroids
• Administration of oral corticosteroids
• Antihistamine therapy via oral and systemic medications

Regular follow up visits with the healthcare provider is recommended.

How can Papular Urticaria be Prevented?

Papular Urticaria may be prevented by taking measures to avoid or minimize insect bites and stings through:

• While playing outdoors, wear clothing that covers the arms and legs
• Use topical insect repellent creams and bug sprays
• Ensure that home pets and farm animals are regularly cleaned of mites and bugs
• Avoid keeping animals in bedrooms, whenever possible
• Use mosquito nets while sleeping, if excluding mosquitos from the sleeping place is not possible
• Vacuum floor carpets and bedding regularly
• Employ the services of a pest control agency, if needed
• If the residential region is heavily infested with ticks and mites, try moving to a new location

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

• The prognosis of Papular Urticaria is generally good with adequate treatment. In many children, the condition is self-limited.
• There may be skin eruptions that come and go, until children outgrow the condition (get desensitized to the causative insect bite), which may take up to a few years

Additional and Relevant Useful Information for Papular Urticaria:

The following DoveMed website link is a useful resource for additional information:

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