Which are the causes of Henoch-Schönlein purpura?

Henoch-Schönlein purpura (HSP) is a type of vasculitis, which is an inflammation of the blood vessels. It primarily affects small blood vessels in the skin, intestines, kidneys, and joints. The exact cause of HSP is not fully understood, but it is believed to be a combination of genetic and environmental factors.

Genetic Factors:

There is evidence to suggest that certain genetic factors may predispose individuals to develop HSP. Studies have shown that HSP tends to run in families, indicating a possible genetic component. However, the specific genes involved in HSP have not been identified yet.

Immune System Dysfunction:

HSP is thought to be an autoimmune disorder, where the immune system mistakenly attacks the body's own tissues. In HSP, the immune system reacts to an unknown trigger, causing inflammation in the blood vessels. This abnormal immune response leads to the characteristic symptoms of HSP, including purpura (purple spots on the skin), joint pain, abdominal pain, and kidney problems.

Infections:

In some cases, HSP may be triggered by an infection, particularly respiratory or gastrointestinal infections. It is believed that certain viral or bacterial infections can stimulate the immune system and trigger the abnormal immune response seen in HSP. Common infections associated with HSP include streptococcal infections, upper respiratory tract infections, and gastrointestinal infections.

Environmental Factors:

Environmental factors may also play a role in the development of HSP. Exposure to certain substances or toxins, such as medications, chemicals, or allergens, may trigger an immune response and contribute to the development of HSP. However, the specific environmental triggers for HSP are not well understood and further research is needed to determine their exact role.

Other Factors:

There are several other factors that have been suggested to contribute to the development of HSP, although their role is not fully understood. These include certain medications, such as antibiotics or nonsteroidal anti-inflammatory drugs (NSAIDs), as well as certain medical conditions, such as autoimmune diseases or cancer. However, more research is needed to establish a clear link between these factors and the development of HSP.

In conclusion, the exact cause of Henoch-Schönlein purpura is not fully understood. It is believed to be a complex interplay of genetic and environmental factors, with an abnormal immune response playing a central role. Further research is needed to unravel the underlying mechanisms and identify specific triggers for this condition.