Clinical problems in the C1-inhibitor deficient patient

Area of Science:

• Immunology
• Genetics
• Biochemistry

Background:

• C1-INH deficiency presents as inherited Hereditary Angioedema (HAE) or acquired angioedema (AAE).
• HAE typically manifests early in life with a family history, while AAE appears later and can be associated with B cell disorders or autoantibodies.
• Both forms involve functional C1-INH, C4, and C2 deficiency; AAE often shows C1 deficiency, unlike HAE.

Purpose of the Study:

• To delineate the clinical and biochemical distinctions between HAE and AAE.
• To review current therapeutic strategies for both forms of C1-INH deficiency.
• To highlight differential treatment responses in inherited versus acquired angioedema.

Main Methods:

• Clinical case review and biochemical analysis of patients with C1-INH deficiency.
• Comparison of disease presentation, family history, and associated conditions.
• Evaluation of treatment efficacy with attenuated androgens, C1-INH plasma concentrate, and antifibrinolytic agents.

Main Results:

• HAE characterized by early onset, family history; AAE by later onset, potential B cell association.
• Biochemical hallmarks include C1-INH, C4, C2 deficiency; C1 deficiency prevalent in AAE.
• Androgens and C1-INH concentrate effective for HAE; AAE shows variable response, requiring higher C1-INH doses or tranexamic acid for prophylaxis.

Conclusions:

• Distinct clinical courses and biochemical profiles differentiate HAE and AAE.
• Treatment strategies must be tailored, with HAE responding well to androgens and C1-INH concentrate.
• AAE management requires individualized approaches, potentially higher C1-INH doses and antifibrinolytics for attack prevention.