C1 inhibitor deficiency

C1 Inhibitor Deficiency Description

C1 inhibitor deficiency, also known as hereditary angioedema (HAE) or acquired angioedema due to C1 esterase inhibitor deficiency, is a rare condition characterized by recurrent episodes of angioedema in the upper respiratory, gastrointestinal tract, or subcutaneous tissues.

Symptoms and Characteristics

• Recurrent circumscribed, non-pruritic, non-pitting oedema (swelling) [6]
• Peripheral pain is not usually a feature, unless swelling occurs on pressure-bearing areas [6]
• Clinically characterized by recurrent episodes of nonpitting asymmetric edema of the face, lips, tongue, limbs, and genitals; severe abdominal pain can also occur [7]

Causes and Diagnosis

• Caused by deficiency or dysfunction of complement 1 (C1) inhibitor [1]
• Main causes of acquired C1-inhibitor deficiency are lymphoproliferative disease and autoimmune disease [2]
• Diagnosis is confirmed by the presence of a low serum C4 and absent or greatly reduced C1 inhibitor level or function [8]

Consequences

• Can cause fatal outcomes if not treated promptly [8]
• Low levels of C1-INH may cause certain types of angioedema, resulting in sudden swelling of the tissues of the face, upper throat, and other areas [9]

Based on my analysis of the provided context, I was unable to find any relevant information about signs and symptoms of C1 inhibitor deficiency in the search results.

However, I can suggest that C1 inhibitor deficiency is a rare genetic disorder that affects the complement system, which is part of the immune system. The condition is characterized by an overactive complement system, leading to excessive inflammation and tissue damage.

Some possible signs and symptoms of C1 inhibitor deficiency may include:

• Recurrent episodes of angioedema (a swelling of the skin and mucous membranes)
• Abnormal bleeding or bruising
• Low levels of certain blood clotting factors
• Increased risk of infections
• Joint pain and inflammation

Please note that these are general possibilities, and I couldn't find any specific information about signs and symptoms of C1 inhibitor deficiency in the provided context.

If you would like me to search again or ask something else, please let me know.

Diagnosing C1 Inhibitor Deficiency

C1 inhibitor deficiency, also known as hereditary angioedema (HAE), can be diagnosed through various diagnostic tests.

• Blood Tests: The initial workup for C1-INH deficiency includes testing for C1-INH and complement 4 (C4) levels [1]. Low levels of these proteins can indicate the presence of HAE.
• Genetic Testing: For individuals with a family history of HAE, genetic testing can confirm the diagnosis by identifying mutations in the SERPING1

Treatment Options for C1 Inhibitor Deficiency

C1 inhibitor deficiency, also known as hereditary angioedema (HAE), is a rare genetic disorder characterized by recurring episodes of severe swelling in various parts of the body. While there is no cure for this condition, several treatment options are available to manage and prevent attacks.

Prophylactic Therapy

Prophylactic therapy involves taking medications regularly to prevent HAE attacks. The following treatments have been found to be effective:

• Androgens: Danazol (Danocrine) and other attenuated androgens can be used for long-term prophylaxis [4].
• Antifibrinolytics: Tranexamic acid, epsilon-aminocaproic acid, and lanadelumab have been found to be more effective for long-term prophylaxis in some cases [3][7].

Short-Term Prophylaxis

For short-term prophylaxis, purified plasma-derived human C1 esterase inhibitor concentrate is the treatment of choice [7]. This medication can be administered intravenously or subcutaneously.

Treatment of Attacks

When an HAE attack occurs, treatment focuses on relieving symptoms. The following measures can be taken:

• Analgesics and antiemetics: Medications such as acetaminophen (Tylenol) and diphenhydramine (Benadryl) can help alleviate pain and discomfort [8].
• Fluid replacement: Intravenous fluids may be administered to prevent dehydration [8].

New Treatment Options

Recently, new treatment options have become available for HAE. These include:

• C1-INH concentrates: Human C1 esterase inhibitor concentrate has been approved for short-term prophylaxis and treatment of attacks [9].
• Berotralstat: This medication is a subcutaneous injection that can be used to prevent HAE attacks [2].

It's essential to consult with a healthcare professional to determine the best course of treatment for individual cases.

Differential Diagnoses of C1 Inhibitor Deficiency

C1 inhibitor deficiency, also known as acquired angioedema or hereditary angioedema (HAE), can be challenging to diagnose due to its rarity and similarity in symptoms with other conditions. Here are some differential diagnoses that should be considered:

• Hereditary Angioedema (HAE): A rare autosomal dominant condition characterized by low levels of C1 esterase inhibitor or poorly functional C1 inhibitors [3][8]. HAE is a genetic disorder that can manifest in three types: type I, where the C1 esterase inhibitor level is reduced; type II, where the C1 esterase inhibitor function is impaired; and type III, where there are low levels of C1 esterase inhibitor.
• Acquired Angioedema: A condition caused by a deficiency or malfunction of C1 inhibitors, which can be triggered by various factors such as autoimmunity, B-cell lymphoproliferative disorders, or genetic mutations [4][5].
• Autoimmune Disorders: Conditions like lupus erythematosus and rheumatoid arthritis can cause acquired angioedema due to the production of autoantibodies against C1 inhibitors.
• Lymphoproliferative Disorders and B Cell Malignancies: These conditions, such as lymphoma or leukemia, can lead to acquired angioedema by producing abnormal proteins that interfere with C1 inhibitor function [7].
• Other Implicated Disorders: Other conditions like idiopathic cases, where the cause of acquired angioedema is unknown, should also be considered in the differential diagnosis.
• Acute Urticaria: A condition characterized by sudden onset of hives and can be a differential diagnosis for acquired angioedema [2]. *