Urticaria (Solar) from Dermatology - Allergy And Immunology.htm - Attention Barry

[Guest guest]

Barry: Welcome to the group although sorry you have had to find us. This article has a pretty comprehensive description of Solar Urticaria and possible treatments.

Will continue to research to see what else I can come up with to try to help you out.

Barb (a fellow mountainbiker)

London, Ontario, Canada

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Urticaria (Solar) from Dermatology/Allergy And Immunology Synonyms, Key Words, and Related Terms: sun hives

Author Information | Introduction | Clinical | Differentials | Workup | Treatment | Medication | Follow-up | Miscellaneous | Bibliography

AUTHOR INFORMATION

Section 1 of 10

Authored by Elma Baron, MD, Photoimmunology Fellow, Department of Dermatology, Case Western Reserve University

Coauthored by R , MD, Assistant Professor, Harvard Medical School, Director of Phototherapy Unit, Department of Dermatology, Massachusetts General Hospital

Elma Baron, MD, is a member of the following medical societies: American Academy of Dermatology

Edited by Belsito, MD, Program Director, Professor, Department of Internal Medicine, Division of Dermatology, Kansas University Medical Center; J Wells, MD, Staff Physician, Department of Dermatology, Texas Tech University Health Sciences Center; Meffert, MD, Program Director, Dermatology Service, San Uniformed Services Health Education Consortium; M Gelfand, MD, Staff Physician, Department of Dermatology, Hospital of the University of Pennsylvania; and Dirk M Elston, MD, Assistant Chairman, Chief, Dermapathology, Department of Dermatology, Combined Army Medical Center/Wilford Hall Medical Center, Assistant Clinical Professor,Department of Medicine,Dermatology Division, University of Texas Health Sciences Center at San

Topic Last Updated: August 27, 2000

Author's Email:

Elma Baron, MD

Editor's Email:

Belsito, MD

INTRODUCTION

Section 2 of 10

Background: Solar urticaria is a rare photodermatosis characterized by pruritus, stinging, erythema, and wheal formation after a brief period of exposure to either natural sunlight or an artificial light source emitting the appropriate wavelength. Initially described by Merklen in 1904, the reaction is localized to exposed areas of the skin, but can occur through thin clothing. Solar urticaria disappears rapidly within several minutes to a few hours without pigmentary change, if further sun exposure is avoided. This disorder can be quite disabling and difficult to manage. It often has a sudden, dramatic onset and little information is available concerning its duration and eventual outcome.

Pathophysiology: Solar urticaria is possibly caused by an antigen-antibody reaction. Solar irradiation may induce an antigen in the serum or plasma of affected individuals. Intradermal injection of serum from a solar urticaria patient passively, but not consistently, transfers the condition to a normal individual. Two types of solar urticaria have been proposed.

Type I is an IgE-mediated hypersensitivity to specific photoallergens generated only in solar urticaria patients. Type II is an IgE-mediated hypersensitivity to nonspecific photoallergens found in both solar urticaria patients and normal individuals.

Passive transfer tests are positive in Type II, and may be positive or negative in Type I solar urticaria. The wide action spectrum (290-800 nm) implicated for this condition may be related to the specific photoallergen and its molecular weight. Diversity in the reported action spectra may be due to differences in photoallergens. In addition, spectra believed to be responsible for either inhibition or augmentation of the reaction have been detected. Complex interactions exist between these various wavelengths and the photoallergen. Mast cell degranulation with subsequent histamine release is the end result of these interactions. It is possible that mediators other than histamines also are involved.

Frequency:

In the US: Solar urticaria comprises only 4% of US patients with photosensitive disorders.

Internationally: Solar urticaria comprises 5.3% of the cases of photosensitive dermatoses worldwide.

Mortality/Morbidity: Mortality rate has not been determined. In some cases, skin eruption is accompanied by symptoms such as headache, nausea, vomiting, bronchospasm, and syncope. Breed: n/a

Race: Condition occurs in all races. Sex: Slight female predilection is noted. Age: Solar urticaria has a wide range of onset (10-70 y) with a mean age of 35 years. It has been reported to occur in infancy.

CLINICAL

Section 3 of 10

History: Due to the transient nature of their eruption, an accurate history is important for the diagnosis of solar urticaria since patients often are seen in the clinic without any obvious lesions.

Patients may complain of pruritus, erythema, and wheal formation of varying degrees after a short period (< 30 min) of sun exposure.

Like most other photodermatoses, skin lesions in solar urticaria may occur on any exposed area, even if skin was covered with thin clothing.

Face and dorsal aspect of the hands, which chronically are exposed to the sun, are affected less severely than other parts of the body, perhaps due to acclimatization and "hardening".

Mucosal involvement (eg, tongue, lip swelling) has been reported.

Other symptoms, such as headache, nausea, vomiting, bronchospasm, and syncope, have been reported, but are considered rare.

Upon cessation of sun exposure, the rash begins to disappear within several minutes to a few hours and rarely lasts beyond 24 hours. Rapid disappearance of the rash when avoiding further sun exposure is essential to the diagnosis of solar urticaria.

Ascertain the following aspects of patient history to rule out other differential diagnoses:

Oral medication intake (eg, chlorpromazine, which may cause a similar photoinduced reaction)

Currently used topical agents (eg, sunscreen or fragrance, which can cause photocontact dermatitis)

Family history of photosensitivity as may occur in some porphyrias

Review medical history regarding other body systems to detect other underlying causes of photosensitivity (eg, connective tissue disorders).

Physical: In most cases, the physical examination will be normal.

During an acute episode, vital signs usually are unaffected; however, systemic symptoms accompanying the cutaneous eruption have been reported.

In rare cases, cardiac and respiratory rates may increase and blood pressure may decrease.

Wheezing may be heard upon auscultation of the chest when bronchospasm is present.

Examination of the skin during an acute episode may reveal lesions in the form of erythematous macules to distinct wheals, the morphology of which may be no different from those lesions found in acute urticaria secondary to other causes.

Eruption follows a photodistribution modified by the type of clothing worn by the affected individual at the time of exposure.

Lesions may be present in areas that are covered with thin clothing, depending on the causative light wavelength and sheerness of the fabric.

Mucosal areas, such as tongue and lips, may be swollen or edematous when affected.

The reaction leaves no residual skin changes. Consequently, examination of the skin after the acute eruption reveals no evidence of condition.

Causes: Solar urticaria possibly is caused by an antigen-antibody reaction. Solar irradiation may induce an antigen in the serum or plasma of affected individuals. Intradermal injection of serum from a solar urticaria patient passively, but not consistently, transfers the condition to a normal individual.

DIFFERENTIALS

Section 4 of 10

Berloque Dermatitis Drug-Induced Photosensitivity Erythropoietic Protoporphyria Lupus Erythematosus (Acute) Polymorphous Light Eruption Urticaria (Acute) Urticaria (Cholinergic)

Other Problems to be Considered:

Miliaria rubra

WORKUP

Section 5 of 10

Lab Studies:

Serologic tests for antinuclear antibody (ANA), Ro, and La antibodies to rule out connective tissue disease such as lupus erythematosus.

Perform testing to rule out metabolic cause (eg, porphyrias).

Evaluate plasma porphyrin level. If abnormal results are found, follow with a quantitative 24-hour urinary and fecal porphyrin measurement, as well as erythrocyte porphyrin determination.

Imaging Studies:

n/a

Other Tests:

Phototesting confirms the diagnosis, identifies the action spectrum, and establishes baseline data (eg, minimum urticarial dose or MUD) for possible therapeutic interventions and monitoring in the future.

Solar urticaria has a wide action spectrum. Perform phototesting using broadband UV-B(290-320 nm), UV-A (320-400 nm), and a visible light source (400-800 nm). The majority of patients with solar urticaria have their provocative wavelengths in the UV-A and visible ranges, especially green or blue.

Duration of exposure under visible light should be < 1 hour. Typically, the light emitted by a slide projector is used. Measures must be taken to avoid excessive heat output from the light source in order to eliminate the possibility of inducing cholinergic or heat-induced urticaria, instead of actual solar urticaria. A water filter may be placed in front of the light source to absorb excess heat.

Phototesting with narrowband UV-B (311-313 nm) is recommended, if possible therapy with this light source is being considered. Occasionally, these tests will not produce the expected reaction.

Phototesting with other light sources (eg, solar simulators, lasers) may be necessary in difficult to establish cases.

Provocation with natural sunlight may be performed if ambient conditions allow.

Many patients with solar urticaria have an inhibition spectrum.

If their skin is first exposed to wavelengths known to induce the solar urticaria, and then immediately afterwards, or possibly concurrently, exposed to radiation within the inhibition spectrum, the urticarial reaction is either eliminated or diminished in intensity.

Procedures:

n/aHistologic Findings: Histologic changes typically are found in the dermis in the form of vasodilatation, increased permeability of the vascular endothelium, and edema. Eosinophil infiltration and deposition of eosinophil granule proteins in the dermis are prominent during early stages of the lesion. Neutrophils also are found in increased numbers around the upper dermal vessels. Dermal mast cells may increase in number. After 24 hours, the dermal infiltrate predominantly is comprised of mononuclear leukocytes.

TREATMENT

Section 6 of 10

Medical Care: In rare systemic cases, supportive medical measures to maintain blood pressure and adequate ventilation may need to be instituted if extensive cutaneous surfaces are involved simultaneously.

Surgical Care: n/a

Consultations: n/a

Diet: n/a

Activity: n/a

MEDICATION

Section 7 of 10

Treatment of solar urticaria can be frustrating. A combination of different modalities often is necessary, but the success of these methods is highly variable. Taking measures to avoid or minimize sun exposure is the most important step. Unfortunately, this often requires major adjustments in lifestyle, which might be impractical for some patients.

Drug Category: Antihistamines (H1 blockers) - Because solar urticaria involves IgE-mediated mast cell degranulation with consequent histamine release, the first line of treatment consists of long-acting, nonsedating H1 blockers. Often such agents will achieve a protective factor of 10 or more. The extent to which this will be useful depends on severity of disease itself. For example, someone who gets hives after just a few seconds of sun exposure is unlikely to benefit from antihistamine monotherapy. A patient requiring 10 min or more of exposure would show more benefit. Antihistamines seem to be able to block wheal response and minimize pruritus, but do not eliminate erythema reaction entirely. This tendency should be explained to the patient.

Drug Name

Cetirizine (Zyrtec)- Forms complex with histamine for H1-receptor sites in blood vessels, GI tract, and respiratory tract.

Adult Dose

10 mg PO qd

Pediatric Dose

< 2 years: Not established 2-5 years: 2.5 mg PO qd > 5 years: Administer as in adults

Contraindications

Documented hypersensitivity

Interactions

Increases CNS toxicity of depressants

Pregnancy

B - Usually safe but benefits must outweigh the risks.

Precautions

Because it is related to the highly sedating antihistamine hydroxyzine, some patients also experience drowsiness upon taking cetirizine; caution in hepatic or renal dysfunction; doses > 10 mg/d may cause drowsiness

Drug Name

Fexofenadine (Allegra)- Competes with histamine for H1 receptors on GI tract, blood vessels, and respiratory tract, reducing hypersensitivity reactions. Does not sedate.

Adult Dose

60 mg PO bid

Pediatric Dose

< 6 years: Not recommended6-11 years: 30 mg PO bid > 12 years: Administer as in adults

Contraindications

Documented hypersensitivity

Interactions

Toxicity increases with coadministration of erythromycin and ketoconazole

Pregnancy

C - Safety for use during pregnancy has not been established.

Precautions

Cardiac complications (dysrhythmias) may occur in high doses; no data available on use while breast-feeding

Drug Name

Loratadine (Claritin)- Selectively inhibits peripheral histamine H1 receptors.

Adult Dose

10 mg PO qd

Pediatric Dose

< 6 years: Not established> 6 years: Administer as in adults

Contraindications

Documented hypersensitivity

Interactions

Ketoconazole, erythromycin, procarbazine, and alcohol may increase loratadine levels

Pregnancy

B - Usually safe but benefits must outweigh the risks.

Precautions

Initiate therapy at lower dose in liver or renal impairmentDrug Category: H2 Antagonists - Usually given in addition to H1 blockers.

Drug Name

Ranitidine (Zantac)- H2 antagonist that, when combined with H1 type, may be useful in treating allergic reactions that do not respond to H1 antagonists alone.

Adult Dose

150 mg PO bid

Pediatric Dose

< 12 years: Not established > 12 years:1.25-2.5 mg/kg/dose PO q12h; not to exceed 300 mg/d0.75-1.5 mg/kg/dose IV/IM q6-8h; not to exceed 400 mg/d

Contraindications

Documented hypersensitivity

Interactions

May decrease effects of ketoconazole and itraconazole; may alter serum levels of ferrous sulfate, diazepam, nondepolarizing muscle relaxants, and oxaprozin

Pregnancy

B - Usually safe but benefits must outweigh the risks.

Precautions

Caution in renal or liver impairment; if changes in renal function occur during therapy, consider adjusting dose or discontinuing treatmentDrug Category: Antimalarials - Used to treat certain photosensitive eruptions including solar urticaria. Their efficacy, however, is unpredictable.

Drug Name

Hydroxychloroquine sulfate (Plaquenil)- Inhibits chemotaxis of eosinophils, locomotion of neutrophils, and impairs complement-dependent antigen-antibody reactions.

Adult Dose

200 mg BID PO

Pediatric Dose

10 mg/kg (base) initial, followed by 5 mg/kg at 6, 24, 48 h

Contraindications

Documented hypersensitivity; psoriasis; retinal and visual field changes attributable to 4-aminoquinolones

Interactions

Serum levels increase with cimetidine; magnesium trisilicate may decrease absorption

Pregnancy

C - Safety for use during pregnancy has not been established.

Precautions

Caution in hepatic disease, G-6-PD deficiency, psoriasis, and porphyria; not recommended for long term in children; perform periodic (6 mo) ophthalmologic examinations (include visual acuity, slit-lamp, fudoscopic, and visual field tests); test periodically for muscle weakness. Periodic blood counts should be checked; hemolysis, aplastic anemia, agranulocytosis, and leukopenia can occur.

FOLLOW-UP

Section 8 of 10

Further Inpatient Care:

n/a

Further Outpatient Care:

Phototherapy with UV-A, broadband UV-B, or narrowband UV-B, as well as photochemotherapy with oral 8-MOP plus UV-A successfully are used in solar urticaria. Desensitization treatments usually are performed in the spring. Unfortunately, the tolerance induced by these modalities is often short lived and maintenance therapy is needed.

A number of protocols exist for the different light sources mentioned, but optimal protocol is not clearly established.

It is important to determine the minimum urticarial dose (MUD) with the specific light box to be used in the treatment.

MUD is repeated during the course of treatment to monitor the patient's progress since development of tolerance usually is paralleled by an increase in the MUD.

If the initial MUD is very low, it is difficult to start the patient on oral 8-MOP photochemotherapy immediately. Initial exposures with UV-A alone may be carried out until the MUD is increased to a level at which oral 8-MOP photochemotherapy can be initiated.

Mechanism of action of phototherapy and photochemotherapy in solar urticaria is not entirely known.

Resulting increase in skin pigmentation and epidermal thickening may be important factors, but are probably not the main mechanism behind tolerance induction.

Some have postulated a UV-induced increase in the mast cell degranulation threshold as a possible mechanism.

PUVA can achieve disease improvement or remission lasting several months. Based on the available evidence, it is probably the treatment of choice for patients not sufficiently helped by antihistamines.

Plasma exchange therapy has been reported effective in a few cases, especially in those patients with a circulating factor in their serum demonstrated by a positive intradermal test. On the contrary, therapy has been reported ineffective in some centers. Until more definitive studies are conducted to evaluate the efficacy of this therapy, it should be reserved as a last resort.

In/Out Patient Meds:

n/a

Transfer:

n/a

Deterrence/Prevention:

Sun exposure must be avoided or minimized as this is the primary causative agent. Educate patients about practical measures such as wearing protective clothing; judiciously applying sunscreens with adequate protection against the causative wavelengths; using UV protective shields over glass windows; and altering lifestyle to minimize the time spent outside during the day (ie, changing job hours or shifting to indoor recreational activities). Some patients with UV-A or visible induced solar urticaria may also find the use of self-tanning lotions containing dihydroxyacetone helpful.

If medical therapy is not successful, some patients will benefit from complete avoidance, or possibly, a combination of avoidance and some medical therapy.

Complications:

n/a

Prognosis:

Solar urticaria is usually a chronic condition. Few patients experience spontaneous remission. Continued intake of oral antihistamines may prevent the whealing to some degree and allow some tolerance to sunlight. Significant and more long-lasting improvement is seen in patients who undergo phototherapy or photochemotherapy. Some patients find that by following preventive measures, their condition becomes manageable.

Patient Education:

Educate patients that despite its persistent and chronic nature, solar urticaria is a benign disorder usually localized to the skin without affecting their general health. It should be emphasized that because response to treatment generally is unpredictable, prevention by avoidance may ultimately be the key in the management of this condition.

MISCELLANEOUS

Section 9 of 10

Medical/Legal Pitfalls:

Ensure that an underlying condition that may present as a photoinduced urticarial reaction (eg, lupus erythematosus, porphyrias) is ruled out by conducting the necessary laboratory exams.

Patients must be well informed of the risks and benefits of antihistamines, phototherapy, photochemotherapy or plasma exchange therapy if these modalities are considered.

Special Concerns:

n/a

BIBLIOGRAPHY

Section 10 of 10

P, Ahamat R, Green C, Ferguson J: Plasma exchange therapy for solar urticaria. Br J Dermatol 1996 Jun; 134(6): 1093-7[Medline]. Dawe RS, Ferguson J: Prolonged benefit following ultraviolet A phototherapy for solar urticaria. Br J Dermatol 1997 Jul; 137(1): 144-8[Medline]. Fotiades J, Soter NA, Lim HW: Results of evaluation of 203 patients for photosensitivity in a 7.3-year period. J Am Acad Dermatol 1995 Oct; 33(4): 597-602[Medline]. A, Burge SM, SA: Solar urticaria in an infant. Br J Dermatol 1997 Jan; 136(1): 105-7[Medline]. Khoo SW, Tay YK, Tham SN: Photodermatoses in a Singapore skin referral centre. Clin Exp Dermatol 1996 Jul; 21(4): 263-8[Medline]. Miyauchi H, Horio T: Detection of action, inhibition and augmentation spectra in solar urticaria. Dermatology 1995; 191(4): 286-91[Medline]. Roelandts R, Ryckaert S: Solar urticaria: the annoying photodermatosis. Int J Dermatol 1999 Jun; 38(6): 411-8[Medline]. Ryckaert S, Roelandts R: Solar urticaria. A report of 25 cases and difficulties in phototesting. Arch Dermatol 1998 Jan; 134(1): 71-4[Medline].

NOTE:

Medicine is a constantly changing science and not all therapies are clearly established. New research changes drug and treatment therapies daily. The authors, editors, and publisher of this textbook have used their best efforts to provide information that is up-to-date and accurate and is generally accepted within medical standards at the time of publication. However, as medical science is constantly changing and human error is always possible, the authors, editors, and publisher or any other party involved with the publication of this text do not warrant the information in this text is accurate or complete, nor are they responsible for omissions or errors in the text or for the results of using this information. The reader should confirm the information in this text from other sources prior to use. In particular, all drug doses, indications, and contraindications should be confirmed in the package insert. FULL DISCLAIMER Topic last updated August 27, 2000.

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Author Information | Introduction | Clinical | Differentials | Workup | Treatment | Medication | Follow-up | Miscellaneous | Bibliography