Allergic purpura, or Schönlein-Henoch disease, is a type of systemic vasculitis. Allergic vasculitis most often occurs in preschool children, especially those who have had various infections such as the flu or chicken pox. The peak incidence occurs in autumn and winter. What are the causes and symptoms of allergic purpura? What is its treatment?

Allergic spots , otherwiseSchönlein-Henoch disease , belongs to the groupof systemic vasculitis.This is a condition in which white blood cells (leukocytes) attack and damage the wall of large or small blood vessels. In the case ofallergic vasculitis , IgA antibodies, which are characterized by the ability to recognize allergens, are responsible for the inflammation and further damage and necrosis of the walls of small blood vessels.

Allergic purpura - causes

Allergic spotsis avascular blemishcaused by an allergic reaction in small vessels. Allergies can be caused by:

  • microorganisms (60-70 percent of patients have a history of upper respiratory tract infections, most often caused by streptococci. Other microbes that may contribute to the disease include rubella, chickenpox, measles, HIV);
  • some medications;
  • vaccines;
  • insect bites;
  • exposure to cold;
  • various chemicals;
  • food allergens (nuts, eggs, meat, milk, tomatoes, fish, chocolate).

Allergic purpura can also be caused by DNA (as in systemic lupus), immunoglobulins in rheumatoid arthritis or cancer antigens.

As a result of an allergic reaction, the body begins to produce IgA antibodies, which accumulate in excess in the blood vessels of the skin, as well as in the joints, digestive tract, kidneys, central nervous system or testes. As a consequence, inflammation develops in these places.

Allergic purpura may also occur in other types of vasculitides with skin involvement, incl. in Wegener's granulomatosis, erythema exudative multiforme, erythema persistent.

Allergic purpura -symptoms

Inflammation of blood vessels increases their permeability. As a consequence, they bleed into the skin, causing a dark red rash (called purpura). It is characterized by the presence of lumps or nodules that:

  • can be felt with your fingers;
  • do not turn pale under pressure;
  • arranged symmetrically;
  • most often found on the lower limbs and buttocks;
  • they usually disappear after 4-6 weeks and usually do not leave a scar;

The accompanying symptoms depend on the places of inflammation:

  • joints - joint pains (mainly knee and ankle joints)
  • digestive system - abdominal pain, most often located around the navel (it is the result of inflammation of the intestinal vessels). It may be accompanied by mild or heavy gastrointestinal bleeding - an admixture of blood in the stool;
  • kidneys - mild to severe hematuria and proteinuria;
  • central nervous system - incl. headaches;
  • testicles - swelling of the testicles.

Allergic purpura - diagnosis

The diagnosis is made on the basis of blood tests (e.g. increased IgA concentration, but parameters of inflammation such as ESR and CRP may be normal or elevated), urine (blood in urine) and stool ( occult blood test). With symptoms of severe renal failure, a biopsy of this organ is necessary.

Allergic purpura - treatment

If the inflammation does not affect organs, incl. kidney or gastrointestinal tract, only symptomatic treatment is used. The patient may be given haemostatic drugs, "sealing" blood vessels (rutin, etamsylate), glucocorticosteroids (for joints), antihistamines and non-steroidal anti-inflammatory drugs (except aspirin, which may exacerbate symptoms of the disease). Skin lesions heal well with dapson.

In the event of kidney involvement, immunosuppressants are used to suppress the immune system, preventing further damage to the kidneys.

Allergic purpura - prognosis

Self-healing occurs within 4-6 weeks. However, in some patients the disease recurs many times.

Category:

Cardiology