macro

is it hive? raised, erythematous, transient, itchy scars, painful, bruising Locations onset, ?trigger Duration and frequency; Timing during day Can you make your hives appear? Triggers: cold, heat, pressure, sun, materials Response to antihistamines Angioedema NSAIDS Red flags: anaphylaxis, thyroid, B symptoms, rheum No burning or pain, bruising, systemic symptoms of fever, weight loss, bone pain, adenopathy, signs of inflammatory arthritis, no skin rashes, no photosensitivity, no Raynaud's, no dry eyes or dry mouth, no oral or genital ulcers.

Chronic spontaneous / inducible urticaria. This is a generally benign, mast-cell mediated idiopathic primary skin disorder. Chronic spontaneous urticaria is typically a self-resolving condition over 2-5 years; chronic inducible urticaria is generally more long lived. In the vast majority of cases it is not a sign of more insidious underlying disease.

> Bloodwork is usually not required for diagnosis, but in certain cases we consider CBC, CRP, LFTs, TSH, Calcium, H. pylori serology
> Non-pharmacologically we recommended:
  > They do/do not have physical triggers that lead to worsening of symptoms. As such, we have advised avoidance of ****
  > Symptoms can be exacerbated by stress and skin abrasions. Recommended regular moisturization at least twice a day to prevent dry skin and stress reduction
  > Food avoidance with elimination diets is contreversial
> For symptomatic management we recommend 2nd generation antihistamines, with titration to 4x the regular dose as required. We have provided:
  > Rupatadine 10mg PO OD, which can be titrated to 40mg OD if required
  > Bilastine 20mg PO OD, which can be titrated to 80mg OD if required
> If refractory to maximal regular antihistamine, we will investigate further for alternative etiologies and consider biologic anti IgE treatment (omalizumab)

*** if COLD induced: there is a risk of more severe reactions including anaphylaxis. As such, we have advised to keep her Epi Pen and to avoid significant cold exposures (cold plunges in water).

approach

prefer mcmac simple approach overall

1. is it actually hives
2. triggers
3. duration
4. red flags something else

What are hives? There is a STRICT defintion

• pruritic
• wheal and flare (pale central clearing with surrounding erythema), but NOT always the case
• should be blanchable
• TRANSIENT (<24-48h)
• superficial dermis
• papules/plaques

Categorization of hives

• acute
• chronic (>6w)
  • inducible
  • spontaneous

CSU (called CIU in the past)

• recurrent spont hives +/- angioedema
• MOST days of the weeks for at least 6 weeks

CSU Epidemiology

• affects up to 1/20 of people during their lives
• not much mortality but it sucks to have
• average age of diagnosis is 30-40 years
• adults >children, mainly F
• is correlated with autoimmune disease in general

50% just isolated urtic 40% with episodic angioedema 10% isolated angioedema

CURE registry: 59% with BOTH 36% wheals alone 5% angioedema alone

Pathophysiology

Eventually mast cells become activated lots of potential pathways to this however but nothing strongly established or known with great certainity it's not confirmed 'autoimmune'

Some of these can include:

• IgG trigger to surface bound IgE similar to an allergen
• IgG binding surface receptors
• self antigen that causes IgE cross linking

P/E

Do dermatographism testing do more thourugh look: HEENT, arthropagis, etc. exam thyroid

Differential

CIU urticaial calsuitis mastocuytoiss schnitzelr syndrome familial cold autoinflammatory sybndrome muckle wells syndreom purritic urtical paules and plaques of pregnancy atopic dermaitis ,ertyehma multiforme, cut lupus ... etc

Testing

differs by org

EAACI: limited at frist, CBC with ESR and CRP choosing widely; no routine, only with clincal indication others: BAT, ASST, skin biopsy ...

Usually in practice these patients often do end up getting a panel skin test for aeroallergens but this is NOT correct... ie. you should not be testing for EVERY single food for example and give false information

Treatment

Education

Not a sign of impedning anaphylxis it is common and mostly BENIGN self resolving QoL solutions in the interim exist that are quite safe and widely used

nonpharm

Avoid triggers stress reduction medications to avoid include nonspecific mast cell activators foods (contrevesial, ie EtOH, though should avoid anyway)

? low histatmine diet ... contrevesial... please see some derm journals on trhis...

pharm

there is sometimes use of oral steroids acutely to treat flares... but would try to avoid if at ALL possible (can increase risk of recurrence after too...)

1-4x 2nd gen AH; aim is COMPLETE control omalizumab next if fails if fails move to changing dose or frequency of omalizumab cyclosporine last line ... but new guidelines coming soon, might be dupi soon as well... also BTK inhibirtor remibrutinib

LOVELY graph given in slides re: step up and step down options and what markers suggest success with each option

Look at network meta analysis for different types of 2nd gen antihistmines

monitoring progress and severity

UAS score ColdUAS CholUAS urticaria control test CU-Q2oL

Prognosis

From eruopean data

• 50% may resolve within 6 months of onset
• 20% in 3 years
• 20% in 5-10 years
• <2% within 25 years, sometimes very longstanding

CIU

Cold induced

typically within min utes and lasts for hour sih ice cube testing caution with significant epxouisrs aresulting in more systemic symptoms

cholingeric

exerfcise, passive rewarming, emotional stress, spicy foods etc papular, short lived provocation testing with exercise, warm clothing/room hives wihtin 10ish minutes of exposure?

Management

similar some ?desnsitivetion but contreversial

The atypicals

urticarial vasculitis