Allergic purpura in the elderly
Introduction
Introduction to allergic purpura in the elderly Allergic purpura (allergicpurpura) is a hemorrhagic disorder caused by abnormal blood vessel wall, mainly due to the body's allergic reaction to certain substances, causing increased capillary permeability and bleeding, which is characterized by allergic vasculitis. The clinical features are Skin purpura, may be associated with abdominal pain, gastrointestinal bleeding, joint pain and / or hematuria, kidney disease. The disease with abdominal and joint pain symptoms called Henoch-Schönlein syndrome, can occur in all age groups, more common in adolescents. basic knowledge The proportion of sickness: 0.5% (the above is the incidence of the elderly) Susceptible people: the elderly Mode of infection: non-infectious Complications: intussusception, renal failure
Cause
The cause of allergic purpura in the elderly
Bacterial infection (20%):
There may be many factors that cause illness, but they are not certain. Clinical statistics show that there are bacteria-induced upper respiratory tract infections (-hemolytic streptococcus), viral infections, parasites; some proteins in food (fish, shrimp) , crabs, dairy products, etc.), have taken some drugs (sulfonamide, penicillin, streptomycin, antipyretic analgesics, etc.) are more common, such as insect bites, pollen, vaccination, trauma, cold, etc., which are common The protein component of the food causes the disease, and there is a recurrence of the food.
Immune complex (20%):
At present, the disease is thought to be caused by immune complexes. It has been found that the skin and renal vasculature can be deposited with IgA, IgG and C3. About 50% of patients are positive for IgA-type rheumatoid factor, and the immune cells can also be detected in the early serum of the disease. Proteins and immune complexes, IgA deposition can be seen by direct immunofluorescence of skin blood vessels. These patients have longer course and better response to adrenal cortical hormone therapy, but the incidence of kidney and joint involvement is higher.
Vascular inflammatory lesions (10%):
In the study, it was found that there is C5b6789 complex (membrane attack complex) in skin and renal vascular disease, and it is considered that complement activation plays an important role in the pathogenesis; IgA-fibronectin is also seen in serum when IgA nephropathy is combined with this disease. Aggregation, in summary, it is currently considered to be an immune complex disease, which is an inflammatory disease-mediated vasculitic lesion.
Prevention
Elderly allergic purpura prevention
The use of immunosuppressive agents in this disease, in addition to pay attention to the observation of blood, pay attention to prevent infection and prevent complications.
Complication
Allergic purpura complications in the elderly Complications, intussusception, renal failure
Common intestinal necrosis, intussusception, renal failure and so on.
Symptom
Symptoms of allergic purpura in the elderly Common symptoms Skin purpura joints swollen intussusception black appetite loss hypertensive nausea and vomiting freckle proteinuria repeated hematemesis
Some patients may have symptoms of upper respiratory tract infection before onset, such as fever, loss of appetite, etc., more common in children, most patients have no prodromal symptoms.
Skin purpura
For the most common manifestations, mainly purpura, more first in the lower limbs, buttocks, ankle joints are most obvious, lesions are often slightly higher than the leather surface, more symmetric distribution, appear in batches, repeated attacks, severe cases can be merged into Freckles, and some can also appear blisters on the redness of the purple spots, and even central necrosis, ulcers and so on.
2. Joint symptoms (Schönlein purplish)
Mainly for joint swelling and soreness, the knee and elbow wrist and ankle joints are more common, can disappear after a few days, leaving no deformity.
3. Abdominal symptoms (Henoch sable)
Mainly for abdominal pain, nausea, vomiting, etc., abdominal examination may have tenderness, rebound tenderness, gastrointestinal hemorrhage manifested as hematemesis or melena, sometimes due to irregular peristalsis, intussusception, intestinal necrosis, surgical treatment.
4. Kidney damage
10% to 20% of adult patients with renal damage, mostly within 2 months of onset, usually only hematuria or microalbuminuria, most patients can gradually disappear, a small number of patients can develop hypertension, renal dysfunction and even kidney Depletion.
Examine
Examination of allergic purpura in the elderly
Mainly the capillary fragility test was positive, the other clotting time and various coagulation function tests were normal, and some patients had increased erythrocyte sedimentation rate.
Fundus examination, retinal oozing and bleeding.
Diagnosis
Diagnosis and differential diagnosis of allergic purpura in the elderly
diagnosis
According to the medical history, physical signs and capillary fragility test positive, except for the number of platelets, function and various coagulation factors can be diagnosed.
Differential diagnosis
Acute rheumatoid arthritis
Because of this disease, there are joint swelling and pain, dysfunction, often misdiagnosed as acute rheumatoid arthritis, but this disease has many skin purpura, can be identified.
2. Acute abdomen
When manifested as abdominal pain or even nausea, bloody stools, hematemesis and other symptoms, should be identified with acute abdomen, systemic examination often found that the skin has purpura, suggesting the disease type.
