Urticaria in Child
Alerts and Notices
SynopsisUrticaria is a skin disorder characterized by wheals (hives), angioedema, or both. It is caused by the release of histamine and other vasoactive substances from mast cells. When swelling is superficial, urticaria presents. When the swelling is deeper, angioedema presents.
Urticaria is categorized as acute (new onset or recurring episodes of up to 6 weeks' duration) or chronic (recurring episodes lasting longer than 6 weeks). Chronic urticaria can be spontaneous or inducible and is estimated to occur in 0.1%-1.8% of children.
The most common cause of acute urticaria in children is viral infection, particularly upper respiratory infections. Other causes include food allergy and drug hypersensitivity. In some cases, the inciting factor is never identified.
Chronic urticaria is less commonly seen in children than in adults. Prognosis is also more favorable in children than in adults, with over 95% resolution after 7 years. Chronic urticaria is subdivided into chronic inducible urticaria and chronic spontaneous urticaria, based on whether definite triggers exist and can be identified. Chronic inducible urticaria is triggered consistently, reproducibly, and exclusively by a specific stimulus. These stimuli further define chronic inducible urticaria subtypes: symptomatic dermographism, cold urticaria, delayed pressure urticaria, solar urticaria, heat urticaria, and vibratory angioedema are physical urticarias, whereas cholinergic urticaria, contact urticaria, aquagenic urticaria, and adrenergic urticaria are not.
Chronic spontaneous urticaria may be exacerbated by triggers such as NSAIDs, alcohol, and stress, but triggers are not definite, as stimuli do not always produce symptoms. While the cause of chronic spontaneous urticaria is unknown, the presence of mast cell–activating autoantibodies in many patients raises the possibility of an autoimmune origin. It is also associated with other autoimmune conditions, including vitiligo and type 1 diabetes mellitus.
Other associated factors:
- Acute urticaria – high population density, allergic disease
- Chronic urticaria – hepatitis B virus, hepatitis C virus, Epstein-Barr virus, mycoplasma, systemic lupus erythematosus, neoplasms (especially lymphoreticular cancers and lymphoproliferative cancers), and oral contraceptive pills (OCPs)
- Chronic induced urticaria – environment (temperature, altitude), allergic disease
- Chronic spontaneous urticaria – gastrointestinal tract infection (Helicobacter pylori, bowel parasites) and inflammation (gastritis, reflux esophagitis, cholangitis), bacterial infection of the nasopharynx, cancer, depression, anxiety, and metabolic syndrome
- Vibratory urticaria – mutation in ADGRE2 (EMR2), which affects mast cell function
L50.9 – Urticaria, unspecified
126485001 – Urticaria
Differential Diagnosis & PitfallsMany serious illnesses present with urticarial lesions and should be considered with every case of urticaria. When in doubt, children should be observed for 2-4 hours to monitor for disease progression.
- Serum sickness / serum sickness-like reaction – Associated with fever, lymphadenopathy, arthralgias (look for refusal to use an extremity), dusky skin lesions, and recent drug (ie, beta-lactam) or sera exposure.
- Urticarial vasculitis – Individual lesions last longer than 24 hours and are associated with pain, purpura, and/or arthralgias or arthritis (look for joint swelling or refusal to use extremities).
- Mastocytosis (urticaria pigmentosa) – Has persistent yellow-brown macules and plaques that urticate with stroking.
- Kawasaki disease – The child appears ill and is febrile.
- Acute hemorrhagic edema of infancy – Large annular purpuric papules and plaques, fever, and edema in an otherwise well infant between the ages of 4 months and 3 years.
- Viral exanthem – Nonspecific viral exanthems tend to be more macular and papular with a diffuse distribution.
- Alpha-gal syndrome – Mammalian meat allergy induced by a tick bite that elicits immunoglobulin E (IgE) antibodies to galactose-alpha-1,3-galactose (alpha-gal), resulting in urticaria, angioedema, and anaphylaxis symptoms 3-6 hours (delayed onset) after ingesting the meat. Implicated tick bites have been noted to be pruritic for 2 or more weeks.
- Erythema multiforme – Fixed for several days, does not respond to antihistamines, and associated with dusky, necrotic centers (rather than the pale edematous center of urticaria).
- Papular urticaria / insect bites – Lesions are often excoriated and last longer than 24 hours.
- Contact dermatitis (irritant, allergic) may have an unusual geometric shape correlating to the inciting irritant and often develops blisters.
- Lupus erythematosus – Often with epidermal changes (scaly, atrophic, or ulcerated).
- Herpes zoster – May initially be urticarial, but lesions are painful and evolve into blisters and crusts.
- Erythema annulare centrifugum – Often with epidermal changes (scale), and lesions persist for weeks.
- Fixed drug eruption
- Exanthematous drug eruption
- Lyme disease
- Erythema marginatum
- Juvenile idiopathic arthritis
- Bedbug bite
- Toxocariasis – A common cause of chronic urticaria.
- African trypanosomiasis
- Cryopyrin-associated periodic syndromes – Muckle-Wells syndrome, familial cold autoinflammatory syndrome (familial cold urticaria), and neonatal-onset multisystem inflammatory disease.
- Phospholipase Cg2–associated antibody deficiency – Lifelong cold-induced urticaria with variable antibody deficiency and increased risk for infection, autoimmunity, and granulomatous disease.
Drug Reaction DataBelow is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.
Patient Information for Urticaria in Child
OverviewHives (urticaria), also known as welts, is a common skin condition with itchy pink or red bumps (papules) that appear and disappear anywhere on the body. In darker skin colors, the redness may be harder to see, but the swollen skin bumps can be felt by the touch. An individual hive typically lasts a few hours before fading away, and new hives can appear as older areas disappear.
Hives can be considered acute (new or periodic episodes lasting less than 6 weeks) or chronic (periodic episodes lasting more than 6 weeks). Although many people have a single episode of acute hives that goes away within a few days to weeks, some may have chronic hives, periodic (recurrent) attacks of hives that come and go over a period of years.
Hives can have many triggers, including:
- Medications, especially aspirin, ibuprofen, naproxen, narcotic painkillers, and antibiotics.
- Infections with viruses, bacteria, and fungi.
- Environmental allergies such as insect bites, pollen, mold, and animal dander.
- Physical exposures such as heat, cold, water, sunlight, and pressure.
- Medical conditions such as gland diseases, blood diseases, and cancer.
- Food allergies such as to strawberries, eggs, nuts, and shellfish.
Who’s At RiskHives appear in people of any age, race / ethnicity, and sex. Hives are very common; it is estimated that up to 20% of the population will develop hives at some point in their lives. Individuals with a family or personal history of atopic conditions (asthma, hay fever, eczema) are more prone to developing hives.
Acute hives are most common in children and young adults, and chronic hives are more often seen in females, especially middle-aged women.
Signs & SymptomsThe most common locations for hives include:
- The trunk.
- The upper arms or upper legs.
Individual hives appear as distinct (well-defined), pink-to-red swellings, which, in darker skin colors, may be easier to feel than see. The bumps range in size from 2 mm to over 30 cm. Some lesions may develop a lighter center. Hives usually appear in groups or batches.
Individual hives disappear within 24 hours, but a single episode may last much longer.
Dermographism is a type of hives that appears within a few minutes of scratching the skin. The rash usually appears in a straight line (linear) pattern.
Swelling of the eyes, mouth, hands, feet, or genitals can sometimes occur with hives. This swelling, called angioedema, usually goes away within 24 hours.
Hives are usually itchy, but they can also burn or sting.
Self-Care GuidelinesIf your child is experiencing mild hives, you can try having them:
- Take cool showers or baths.
- Apply cool compresses.
- Wear loose-fitting clothes.
- Avoid strenuous activity.
- Use an over-the-counter antihistamine such as cetirizine (Zyrtec), fexofenadine (Allegra), loratadine (Claritin), or diphenhydramine (Benadryl).
When to Seek Medical CareIf your child's hives make it difficult to breathe or swallow or if your child feels lightheaded, call 911.
In nonurgent situations, see your child's medical professional if the hives do not improve with treatment or if they continue to appear for more than a few days.
Before visiting your child's medical professional, try to notice what might be triggering the hives and whether it improves or worsens with exposure to heat, cold, pressure, or vibration. Take a list of every medication (prescription and over the counter), supplement, and herbal remedy your child may have taken recently. Also consider any recent illnesses your child has had because some illnesses (and their treatments) can trigger hives.
TreatmentsAfter confirming that your child has hives, the medical professional will work with you and your child to discover the possible cause. They will also take a detailed medical history and may do blood tests.
The best treatment for hives is to discover any triggers and stop your child's exposure to them. However, most people with hives do not know the cause and require medication to get rid of the hives.
The most common medications for hives include:
- Non-sleep-causing (nonsedating) antihistamines such as loratadine (Claritin) for ages 2 years and older, cetirizine (Zyrtec) for ages 2 years and older, fexofenadine (Allegra) for ages 6 months and older, or desloratadine (Clarinex, Aerius) for ages 6 months and older.
- Sleep-causing (sedating) antihistamines such as diphenhydramine (Benadryl) for ages 2 years and older or hydroxyzine (Vistaril, Atarax).
- Your physician may prescribe other antihistamine or anti-inflammatory medications.
In rare situations, the medical professional might prescribe a short course of oral corticosteroid pills (a steroid). Other classes of oral or injectable medications may be prescribed for recurrent hives that do not respond to these measures.
Urticaria in Child