Defects in the complement system Save

Defects in the Complement System

The complement system is an essential part of the immune system, playing a crucial role in the defense against infections and the removal of damaged cells. However, defects in the complement system can lead to various health complications. In this article, we will explore some common defects associated with the complement system.

1. Hereditary Angioedema (HAE):

HAE is a rare genetic disorder caused by a defect in the complement system. It leads to recurrent episodes of localized swelling in various parts of the body, including the face, limbs, and gastrointestinal tract. These episodes can be sudden, severe, and potentially life-threatening.

2. Complement Component Deficiencies:

Deficiencies in specific complement components, such as C1, C2, C3, and C4, can impair the overall functioning of the complement system. These deficiencies can make individuals more susceptible to infections, particularly with encapsulated bacteria, such as Streptococcus pneumoniae and Neisseria meningitidis.

3. Systemic Lupus Erythematosus (SLE):

SLE is an autoimmune disease that can involve defects in the complement system. In SLE, the complement system becomes overactive, leading to chronic inflammation and tissue damage. This dysfunction can contribute to the development of various symptoms, including joint pain, skin rashes, and kidney problems.

4. Atypical Hemolytic Uremic Syndrome (aHUS):

aHUS is a rare disorder characterized by the abnormal activation of the complement system, particularly in the blood vessels. This uncontrolled activation can result in the destruction of red blood cells, kidney damage, and other complications. aHUS can be caused by genetic mutations or acquired factors.

5. Paroxysmal Nocturnal Hemoglobinuria (PNH):

PNH is a rare acquired hematopoietic stem cell disorder that leads to defects in the complement regulatory proteins, specifically CD55 and CD59. This deficiency makes red blood cells more susceptible to complement-mediated destruction, resulting in anemia, blood clots, and other related symptoms.

It is important to note that defects in the complement system can have varying degrees of severity and can present differently in individuals. Proper diagnosis and management by healthcare professionals are crucial to minimize the impact of these defects on one's health.

In conclusion, defects in the complement system can give rise to several health conditions, including HAE, complement component deficiencies, SLE, aHUS, and PNH. Recognizing the signs and symptoms associated with these defects can aid in early diagnosis and appropriate medical intervention.