Chronic Spontaneous Urticaria (CSU)

CSU is defined by recurrent hives, angioedema, or both for >6 weeks without an obvious external trigger. It is believed to involve autoimmune activation of mast cells and basophils. Although not life-threatening, CSU significantly impacts sleep, work, and mental health.

Symptoms

• Transient wheals (hives) that itch or burn, lasting <24 hours in one spot
• Angioedema (swelling of lips, eyelids, extremities)
• Symptoms often worse at night or with stress
• Systemic symptoms (fever, joint pain) suggest alternative diagnoses

Diagnosis

• Clinical diagnosis based on history and physical
• Rule out physical urticarias (cold, cholinergic, dermographism), drug reactions, autoimmune disease, infections
• Basic labs: CBC, ESR/CRP, TSH; broader workup guided by history
• Urticaria Control Test (UCT) to assess severity

Treatment – Stepwise (EAACI/AAAAI Guidelines)

1. Standard-dose second-generation H1 antihistamines (cetirizine, loratadine, fexofenadine, etc.)

2. Up-dosing antihistamines up to 4x standard dose if symptoms persist

3. Add-on biologic or immunomodulator:

• Omalizumab (anti-IgE) every 4 weeks
• Cyclosporine (monitor kidney/BP)
• Dupilumab emerging for omalizumab-refractory cases

4. Short course of oral corticosteroids for severe flares (avoid chronic use)

Adjuncts

• H2 blockers (famotidine), leukotriene receptor antagonists (montelukast) for partial responders
• Sedating antihistamines at night for sleep issues
• Treat comorbidities (autoimmune thyroid disease, stress, infections)

Lifestyle

• Identify and avoid aggravating factors (NSAIDs, alcohol, heat, tight clothing)
• Manage stress and sleep deprivation
• Keep skin moisturized; avoid hot showers if triggers

Living with CSU

• Track hive frequency, angioedema episodes, triggers, medications, and response scores
• Carry an emergency plan if angioedema involves airway
• Seek mental health support; anxiety/depression common
• Consider allergy referral for biologic therapy access

Complications

• Airway compromise from angioedema (rare but serious)
• Adverse effects of chronic steroids or immunosuppressants
• Social/occupational impairment due to itching and appearance

Research & Future Directions

Investigations target mast cell signaling, autoimmune biomarkers, and microflora influences.

Experimental & Emerging Treatments

• Ligelizumab: Next-gen anti-IgE with higher affinity than omalizumab.
• BTK Inhibitors (remibrutinib, fenebrutinib): Reduce mast cell activation.
• Siglec-8 Antibodies: Deplete eosinophils/mast cells driving CSU.
• Microbiome & Metabolomic Profiling: Identify personalized dietary or probiotic interventions.

Track CSU with Diagnoza.care

Calm the Hives with Data – Log daily symptoms, UCT scores, triggers, antihistamine doses, biologic injections, angioedema episodes, and healthcare visits; capture side effects; and let the AI companion highlight patterns or flares needing therapy escalation.

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Medical Disclaimer: Informational only. Work with your allergist/dermatologist to personalize antihistamine up-dosing, biologic selection, and monitoring plans. Sources: European Academy of Allergy and Clinical Immunology (EAACI), American Academy of Allergy Asthma & Immunology (AAAAI), World Allergy Organization