1. Physical urticarias Boonthorn 30 December 2009

2. Mechanical Symptomatic dermographism Delayed pressure urticaria Vibratory angio-oedema Thermal Cholinergic urticaria Localized heat urticaria Cold contact urticaria Other Exercise-induced anaphylaxis Solar urticaria Aquagenicurticaria Outline Physical urticarias

3. Clinical appearance rapid appearance of wheals and/or angioedema wheal consists Central swelling of variable size, almost invariably surrounded by reflex erythema itching or sometimes burning sensations with skin return to normal appearance, usually within 1–24 h Urticaria ( Definition ) EAACI/GA 2LEN/EDF guideline. Allergy 2006: 61: 316–320

4. wheal demonstrates edema of upper and mid-dermis dilatation of postcapillaryvenules and lymphatic vessels of upper dermis Upregulation of endothelial adhesion molecules mixed inflammatory perivascular infiltrate of neutrophils and/or eosinophils, macrophages and T-helper lymphocytes mild to moderate increase of mast cell numbers Urticaria ( histology ) EAACI/GA 2LEN/EDF guideline. Allergy 2006: 61: 316–320

5. Classification of urticaria EAACI/GA 2LEN/EDF guideline. Allergy 2006: 61: 316–320

6. subset of chronic urticaria. approximately 20% - 30% of chronic urticaria induced by variety of environmental stimuli eg. exercise, temperature changes, cold, heat,pressure, sunlight, vibration, and water physical stimuli are predominant cause of condition incidental factor in case of chronic idiopathic urticaria multiple physical urticarias ( small number ) Physical urticarias J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

7. Dermographism( urticariafactitia )

8. means to‘‘write on the skin’’ most common of physical urticarias incidental finding in evaluation of other skin conditions ( AD, CIU, and other PU ) rapid onset of cutaneous wheal & flare after experiencing skin pressure Epidemiology Simple dermographism( most common ) approximately 2-5% of general population Symptomatic forms ( much less common ) no prevalence data Dermographism( urticariafactitia ) J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

9. Clinical features simple dermographism Wheal provoked by stroking skin with firm object typically appears within 6-7 minutes and begins to fade 15 to 30 minutes later symptomatic dermographism appearing in <5 minutes and lasting 30 minutes red dermographism( variants of symptomatic ) Follicular or inflamed and swollen Purposeful stroking ( most common ) Unaware inciting event eg. Scratch (dry skin) Severe dermographism ass. With urticariapigmentosa or systemic mastocytosis Dermographism( urticariafactitia ) J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

10. Pathogenesis remains uncertain Elevated levels of serum histamine (whealing episode) successful passive transfer serum from dermagraphicpatient transferred dermographismto monkey Suggest IgE-mediated reaction, but no allergen has been identified Dermographism( urticariafactitia ) J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

11. Diagnostic testing Stroking skin with firm object, eg. tongue blade Provokes typical wheal&flare response (few mins.) not taking antihistamines Dermographometer ( research ) Apply well-defined,reproducible amount of pressure to subject’s skin useful in documenting response to therapy Threshold in simple dermographism:4900 g/cm2 in symptomatic dermographismthe threshold is 3200 -3600 g/cm2 Dermographism( urticariafactitia ) J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

12. Dermographism( urticariafactitia ) weal response without itch on provocation at 60 g/mm2 (589 kPa) or higher indicates simple dermographism John Wiley & Sons A/S Allergy 2009: 64: 1715–1721

13. Treatment Simple dermographism(asymptomatic) : requires no therapy symptomatic dermographism: avoidance of any inciting triggers use of medications skin hydration and emollients ( prevent scratch ) H1 antihistamines H2 antihistamine ( IF FAIL H1 alone ) UVB light Dermographism( urticariafactitia ) J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

14. Dermographism( urticariafactitia ) Narrowband ultraviolet B phototherapy is beneficial in antihistamine-resistant symptomatic dermographism: pilot study J Am Acad Dermatol 2008;59:752-7.

15. Delayed pressure urticaria Pressure swelling provoked by a bra strap F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258

16. marked subcutaneous swelling after application of sustained pressure stimulus to skin Occur in 30 minutes,typically 4 to 6 hours may persist for up to 48 hours , distinguished from other physical urticarias dependent on degree of pressure, duration of stimulus, body site affected, activity of disease DPU are provoked (distinguished from CIU) Should be considered in all patients with CIU whose disease is unresponsive to antihistamines Delayed pressure urticaria F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258

17. Epidemiology Incidence 2% among 2310 urticaria1 37% in 135 pts. In urticaria clinic2 Male:female =2:1 Onset 5-63 yrs. (peak onset 30-40) Duration 1-40 yrs. (mean 9yrs.) ,fluctuate condition Delayed pressure urticaria F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258 Champion RH. Br J Dermatol 1988;119:427 2. Barlow RJ.et al. J Am Acad Dermatol 1993;29: 954– 8.

18. Clinical features erythema and cutaneous and subcutaneous swelling Edema of hands and feet (difficult to distinguish from idiopathic angioedema) Common triggers Long walks, manual activities using heavy objects, overstaying in standing or sitting position, and wearing tight clothes Local symptoms Burning pain , warm sensation, dysesthesias, stinging, and local tension,True itch is rare Localization of lesions Sites of sustained and constant pressure (e.g., palms, soles, buttocks, and shoulders) Delayed pressure urticaria F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258 LawlorF,et al. Br J Dermatol 1989;120:405. CzarnetzskiBM,et al. Br J Dermatol 1984;111:315

19. Clinical features Time of onset : 30 min.( early) , 4-6 hrs.(most) Duration of lesions mean, 22–38 hours; range, 8–72 hours Systemic symptoms up to 50% of patients, even if rarely relevant: shivering, hyperpyrexia,dizziness, arthralgia, nausea, headache, short breath, and asthenia Elevated ESR (17-71%) , α-1 and total antitrypsin (acute phase reactant) Neutrophilia without eosinophilia Delayed pressure urticaria Dermatologic Therapy, Vol. 22, 2009, S22–S26

20. Pathogeneis Not known Proposed mechanism Late phase reaction ( timing ,cell infiltrate,histopathology) Type III or other reaction to unknown allergy ( timing, histopathology , but no evidence of vascular damage DIF : negative & normal complement ) mast cell (histmine ,leukotriene not major part) IL-6 increase in lesion ( but nonspecific) Eosinophil ( found eosinophilic major basic protein) Upregulation of ELAM-1(6hrs.),VCAM-1(24hrs.) Delayed pressure urticaria F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258

21. Diagnostic testing Pressure testing ( no standard method) Positive pressure challenge at least 30 min. Usually read pressure test at 6 hrs. Hanging 15-lb weight at end of crepe bandage over shoulder, thigh, or forearms at least 15 minutes ( usful in clinical setting , not for clinical trial ) apparatus in (known weight)metal rods are held vertically in place, resting on patient’s back Calibrated dermographometerwith spring loaded tip , press right angle to back lat. to spine (99.4g/mm2) 5,15,33,70(optimal),100 sec. Delayed pressure urticaria F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258

22. Delayed pressure urticaria John Wiley & Sons A/S Allergy 2009: 64: 1715–1721

23. Delayed pressure urticaria Pressure instrument adapted from Illig and Kunick with weighted rods resting on a patients’ back. Experimentally produced pressure swelling using pressure instrument F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258

24. Delayed pressure urticaria calibrated dermographometer. The setting of 10 =pressure of application of 9.75 * 105Pascals. The tip is pressed perpendicularly into the skin and held in place for 5, 15, 30, 70, or 100 seconds Experimentally produced pressure papules using the dermographometer F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258

25. Treatment Activities cause problem ,be modified or stopped No single effective drug treatment adequate doses of antihistamine eg. Cetirizine 10 mg q 8hrs.1 Prednisolone at least 30 mg/d may be used in short period for acute severe exacerbation Aspirin (3900mg/d) not suppress completely colchicine, indomethacin (75mg/d) ineffective Nimesulide+ketotifen improved compared with steroid Delayed pressure urticaria F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258 1. Kontou-Fili K, et al. J Am AcadDermatol 1991;24:1090.

26. Treatment Dapsone 50mg/d ( clear,5pts.)1 Sulphasalazine 4g/d ( 2pt.)2 Montelukast 10 mg/d for 1 week( 1 pt.)3 Montelukast +nonsedate antihistamine eg. Desloratadine > antihistamine alone Cyclosporin (3mg/kg/d)4 IVIg ( 0.4g/kg/d for 5 d )4 =>5/8 response Delayed pressure urticaria F. Lawlor, A. Kobza Black / Immunol Allergy Clin N Am 24 (2004) 247–258 Gould DJ et al. Br J Dermatol 1991;125:25. Engler RJM et al. Am Au Ast Immunol 1995;74:155 Berkun Y et al. Allergy 2000;55:203. Kobza Black A . J Invest Dermatol 2001;6:148

27. development of pruritus and swelling after application of vibratory stimulus to the skin Epidemiology Reports are rare in literature hereditary vibratory angioedema (AD) (4pt.) sporadic and generally related to occupation Vibratory angioedema J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

28. Clinical features After experiencing appropriate vibratory stimulus, complain of local pruritus, erythema, and swelling arising within few minutes Symptoms peak in severity at 4-6 hours and typically resolve by 24 hours Riding motorcycle, horse, or mountain bike; handling jackhammer; mowing the lawn; toweling; massaging; clapping; and walking severity and duration to be proportional to : intensity and duration of applied vibratory stimulus area of exposed body surface Vibratory angioedema J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

29. Pathogenesis not been satisfactorily elucidated Elevated levels of serum histamine and mast cell degranulation Passive transfer experiments : negative nonimmunologic immediate hypersensitivity reaction Direct mast cell stimulation from vibration may lead to degranulation and local release of histamine Vibratory angioedema J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

30. Diagnostic testing subject’s arm is held on level plane, and a vortex mixer is placed in contact with the skin applied for 5 minutes observed for 5 to 6 hours If positive, develop pruriticerythema and edema around full circumference of the arm Dermatographism and pressure urticaria should be excluded using the appropriate tests Vibratory angioedema J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

31. Vibratory angioedema -vibratory angioedema and weal can be reproduced using a laboratory vortex mixer -measurement of circumference of arm before and after challenge at 3 points (wrist, mid-forearm, elbow) can help define vibration induced swelling John Wiley & Sons A/S Allergy 2009: 64: 1715–1721

32. Treatment avoidance of specific vibratory stimuli H1 antihistamine using a 5-minute desensitization protocol every 5 to 7 days Vibratory angioedema J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

33. cholinergic urticaria Hives induced in patient with cholinergic urticaria after running in place for 10 minutes

34. “generalized heat urticaria” precipitated by increase in core body temp. Common triggers : exercise, strong emotions, bathing in hot water, ingestion of spicy or hot foods Epidemiology 5% of all cases of chronic urticaria 30% of all cases of physical urticaria onset : during second or third decade of life Male = female Cholinergic urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

35. Clinical features Numerous punctate wheals (1–3 mm) surrounded by large flares tingling, itching, or burning sensation of skin before appearance of hives typically begin on trunk and neck and spread distally to involve face and extremities Systemic symptoms ( rare cases ) eg. hypotension, angioedema, and bronchospasm must be differentiated from exercise-induced anaphylaxis (only appear with exercise) Cholinergic urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

36. Cholinergic urticaria demonstrated Postulated Pathogenesis not been fully elucidated increased number of muscarinic receptors in areas that demonstrate hives Elevated levels of histamine (during attack) neurogenic reflex type I allergy to own sweat abnormal cutaneous response in presence of cholinergic agents associated with hypohidrosis J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

37. Diagnostic testing intradermal injection of 0.01 mg of methacholine in 0.1 mL saline produces local area of hives ( positive 1/3 , not used to rule out) Specific provocative challenges ( but not specific ) Best diagnostic tool : submerged partially in hot water bath at 40ºC until core body temp. increased > 0.7ºC => genealizedurticaria ( aquagenic can produce only submerge portion ) Cholinergic urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

38. Cholinergic urticaria test is positive if exercise challenge leads to typical rash over 10 min John Wiley & Sons A/S Allergy 2009: 64: 1715–1721

39. Treatment Identification and avoidance of known triggers Medical therapy Oral antihistamines Ketotifen anabolic steroid danazol (reserved only for severe cases refractory to antihistamines) Beta-blocker ( use with extreme caution ) Prognosis Favorable ( only 1/3 persist > 10yrs. ) Average duration 7.5 yrs. ( 3-16 yrs. ) Cholinergic urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

40. warm stimulus :direct contact with skin result in formation of wheal within minutes must be differentiated from cholinergic urticaria and solar urticaria Pathogenesis : histamine release (mast cell cause of condition) Passive transfer experiments : negative Diagnostic testing application of test tube containing water at 44ºC to arm for 4-5 mins. =>localized hive develop within few mins. Temp test Treatment antihistamines and oral cromolyn not been effective Desensitization using hot baths successful in 1pt. Local heat urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

41. Local heat urticaria Thresholds may allow for determination of disease activity and for assessing response to therapy John Wiley & Sons A/S Allergy 2009: 64: 1715–1721

42. Acquired cold urticaria(cold contact urticaria) Positive ice cube test in a patient with cold urticaria

43. development of weal-and-flare type skin reactions and ⁄ or angiooedema after exposure of the skin to cold Fourth commonest type of longlastingurticaria occur minutes after the skin is exposed to cold air, liquids or objects extensive cold contact may result in generalized urticarial symptoms +/- systemic reactions endangered by drowning when swimming in cold water suffocation due to pharyngeal angiooedema after consuming cold foods and beverages Acquired cold urticaria F. Siebenhaar et al.Clinicaland Experimental Dermatology, 32, 241–245

44. Epidemiology most frequently affects young adults Mean duration : 4–5 years remission or at least improvement of symptoms in 50% of patients within 5 years Women > men (twice) Incidence 0.05% of urticaria 5.2 - 33.8% of physical urticaria Varies depending on study and geographical region, i.e. higher incidences with cold climate Acquired cold urticaria F. Siebenhaar et al.Clinical and Experimental Dermatology, 32, 241–245

45. Acquired cold urticaria DDx of ACU F. Siebenhaar et al.Clinical and Experimental Dermatology, 32, 241–245

46. Acquired cold urticaria DDx of ACU F. Siebenhaar et al.Clinical and Experimental Dermatology, 32, 241–245

47. Pathogenesis Still remain largely unclear Postulate autoimmune mechanism interaction of IgEautoAbwith cold-dependent skin Ag Cold temperatures presumably encourage interaction of IgM or IgG anti-IgEAb with IgE attached to mast cells, activate mast cells (primary target cell) and cause mediator release ( histamine,PGD2,PAF,neutrophil&eosinophil chemotactic factor Acquired cold urticaria A.A. Wanderer, H.M. Hoffman / Immunol Allergy Clin N Am 24 (2004) 259–286

48. etiology Secondary ACU Cryoglobulinemia : secondary to CLL, lymphosarcoma, LCV, HCV infection, and angioimmunoblasticlymphadenopathy Infectious diseases ( virus&bact.) infectious mononucleosis ,Syphilis , rubeola, varicella, hepatitis , and respiratory viral infections Leukocytoclasticvasculitis Miscellaneous: insect stings, drugs(eg. Penicillin ,oral contraceptive, ACEI), neoplasms Acquired cold urticaria A.A. Wanderer, H.M. Hoffman / Immunol Allergy Clin N Am 24 (2004) 259–286

49. Diagnostic testing first aim To confirm ACU by performing simple cold-provocation testing positive immediate cold-stimulation test (CST): development of urticarial skin lesions at sites of cold challenge most common : application of ice cube to skin Second Determine disease activity and monitor response to therapeutic interventions threshold testing for critical cold-stimulation times and ⁄ or temperatures (Peltier effect based electronic device) Acquired cold urticaria Clinical and Experimental Dermatology, 32, 241–245

50. Acquired cold urticaria John Wiley & Sons A/S Allergy 2009: 64: 1715–1721

51. Acquired cold urticaria CSTT performed with beakers filled with ice slurry. Confluent wheals appear after 2- and 4-minute applications of cold stimulus to separate skin sites. minimum time of cold stimulus (CSTT) was 2 minutes for this patient. A.A. Wanderer, H.M. Hoffman / Immunol Allergy Clin N Am 24 (2004) 259–286

52. Acquired cold urticaria Peltier effect-based electronic device (TempTest) for diagnosing and monitoring ACU symptoms. (a,d) Control unit with ⁄ without applicator; (b) applicator with 12 stimulators; (c) example of use Clinical and Experimental Dermatology, 32, 241–245

53. Acquired cold urticaria Critical temperature thresholds (CTTs) and their changes in ACU are correlated with disease severity and with changes in ACU activity, respectively. ACU severity (a, n = 16) changes in disease activity (b, n = 19) were assessed in patients with ACU using a three-item and a five-item Likert scale, respectively British Journal of Dermatology 2010 162, pp198–200

54. Treatment Avoidance of cold prevent ACU symptoms,serious events Threshold testing help to recognize and control cold exposure in daily life Symptomatic therapy antihistamines : most effective symptomatic therapeutic option to prevent and reduce reactions Required high dose antihistamine(4*) insufficiently treated patients with severe ACU are at risk of developing life-threatening complications Acquired cold urticaria Clinical and Experimental Dermatology, 32, 241–245

56. Further treatment options induction of cold tolerance (effective method), needs to be done very cautiously under supervision because of risk of systemic reactions, required high patient compliance Treatment with topical capsaicin,reportedto prevent ACU symptoms results in depletion of neuropeptidesfrom sensory nerve fibres (pathogeneticrole remains to be clarified in detail ) Acquired cold urticaria Clinical and Experimental Dermatology, 32, 241–245

57. exercise is only trigger in exercise-induced anaphylaxis isolated entity ,association with food ingestion, medication use, and menstruation Epidemiology Age of onset from 4-74 yrs. (mean,24.7 yrs.) Female 71% of population 50% had personal Hx of atopy Exercise–induced anaphylaxis J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

58. Clinical features prodromal phase ( fatigue, warmth, pruritus, and erythema ) progress to large hives that become confluent and eventually appear as angioedema develops into systemic anaphylaxis with cardiovascular (hypotension, syncope), respiratory (wheezing, stridor), and gastrointestinal (colic, nausea, vomiting) symptoms. Once fully developed, attacks last 30 minutes to 4 hours late phase : manifests as headache, fatigue, and warmth and could last from 24 to 72 hours Exercise–induced anaphylaxis J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

59. Clinical feature most commonly triggered by jogging, brisk walking, dancing, and aerobic sports Other factors : menstruation , use of aspirin and NSAIDs, and exposure to cold weather Reaction variable , not reproducible in same activity Variant type : punctate wheal , triggered only by exercise and not by elevations in core body Temp. food-dependent, exercise-induced anaphylaxis Exercise–induced anaphylaxis J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

60. Pathogeneis elevations in levels of serum histamine and tryptase during attacks cause of the mast cell degranulation remains uncertain. Postulated reactions may be IgE mediated priming phenomenon may be at work , with food, medications, or other stimuli acting as necessary cofactors Exercise–induced anaphylaxis J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

61. Diagnostic testing Exercise testing is method of choice running on treadmill or using a stationary bicycle with incremental increases in exertion Passive warming tests to rule out cholinergic urticaria with systemic symptoms difficult to reproduce false-negative challenges are common Testing may need to be repeated on multiple occasions to prove the diagnosis Exercise–induced anaphylaxis J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

62. Treatment identify and avoid any specific foods, medications, or other associated factors carry self-injectable epinephrine at all times exercise with a partner who is trained to use epinephrine avoid exercising within 4 - 6 hours of eating not exercising during extremely hot, humid, or cold weather or during an allergy season Antihistamine therapy : only partial benefits in preventing exercise-induced anaphylaxis and not prevent severe attack Long term F/U : stable (46%),decrease (47%) Exercise–induced anaphylaxis J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

63. direct exposure of the skin to sunlight Epidemiology 0.4% of urticaria higher incidence in women mean age at initial presentation 35 years (range, 17–71 years) risk factors for solar urticaria, such as patient age, atopic history, and wavelength of light Solar urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

64. Clinical features classic wheals only erythema, itching, or a sensation of burning DDx with sunburn ( more rapid,only minutes) limitation of physical findings to areas of the body exposed to direct sunlight Severity increases with intensity of sun exposure anaphylactic reactions are possible if exposed body surface area is large enough disappearance of urticaria within 24 hours Solar urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

65. Pathogenesis hypothesized : presence in skin of precursor molecule , activated by exposure to particular wavelength of light =>photoallergen Origin of precursor molecule not been determined Type I ( abn. Precursor molecule not found in healthy ) Type II ( common precursor molecule ,found in all ) passive transfer is not always successful eliminated by removing horny layer of the skin Solar urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

66. Diagnostic testing Phototesting exposed to varying wavelengths using a monochromatic light source, and threshold dose, which induces erythema or urticaria exposure to other light sources, eg. natural sunlight, high-intensity UV light, or slide-projector light, induced symptoms Solar urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

67. Solar urticaria John Wiley & Sons A/S Allergy 2009: 64: 1715–1721

68. Treatment Antihistamines : drug of choice Topical & systemic steroids : used if antihistamines are insufficient Desensitization ( last only few days ) PUVA ( more long lasting protection , greater long-term adverse effect ) Plasmapharesis +/- PUVA (may depend on characteristics of specific photoallergen at work Longterm F/U : 25% complete resolution , 32% improved , 35% unchange , 8% worsened Solar urticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

69. direct skin contact with water Epidemiology rare disorder with < 50 cases ( case report ) Female > male Age of onset : at or slightly after puberty Familial occurrences have been reported personal or family Hx of atopy occasionally reported Aquagenicurticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

70. Clinical features small, punctuate (1–3 mm), perifollicular wheals may occur on all parts of body, although generally not on palms and soles ( Indistinguishable from cholinergic urticaria ) Wheals appear rapidly after direct contact with any source of water (ie, distilled, tap, or saline) not influenced by temperature or pH fade within 30 - 60 minutes Alcohol and other organic solvents applied to skin do not lead to wheal formation Aquagenicurticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

71. Clinical features Systemic symptoms are rare refractory period lasting several hours primary differential diagnoses : cholinergic urticaria ( Exercise, sweating, heat, and strong emotions ) aquagenicpruritus (occurs on skin contact with water but lacks visible cutaneous manifestations) Aquagenicurticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

72. Pathogenesis still is poorly understood postulated that water interacted with sebum to form substance capable of acting as direct mast cell degranulation Enhancing ability of water to penetrate stratum corneum increases the wheal-provoking effects of water (complete removal of stratum corneum , rather than preventing urticaria, worsen reaction) Activation of cholinergic pathway (ability of the acetylcholine antagonist scopolamine to suppress wheal formation ( some study not suppress) Methacholine injection : negative Aquagenicurticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

73. Diagnostic testing standard test : application of water compress at 35ºC ( room temp.) to upper body for 30 minutes extremities, are affected less commonly in aquagenicurticaria Certain areas of skin with thickened epidermal layer may be less desirable for testing because of reduced penetration of water rule out other physical urticarias ( cholinergic and cold-induced urticaria ) Aquagenicurticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

74. Treatment Antihistamine therapy : variable response Barrier method : application of petrolatum ointment UVB light treatment twice a week PUVA therapy Anabolic steroid stanozol Aquagenicurticaria J.P. Dice / Immunol Allergy Clin N Am 24 (2004) 225–246

75. conclusion Pathogenesis for these disorders remains unclear sensitivity by the mast cell to environmental stimuli future research is needed conditions share the features of rapid onset and relatively short duration (except delayed pressure urticaria) there is enough variability in presentation

76. Diagnostic testing should be completed for several of these conditions in each patient Because of occasional overlap of triggers and occasional coexistence of multiple physical urticarias, Treatment generally avoidance of known triggers use of antihistamines for prophylaxis Other modalities are occasionally effective Life-threatening,systemicsymptoms are rare (except in exercise-induced anaphylaxis) but must be considered Self-injectableepinephrine should be provided to any patient at risk conclusion