Selective immunoglobulin A deficiency is an primitive immunodeficiency and the most common and primitive antibody deficiency. Undetected form is defined as total serum immunoglobulin A level of 5 mg / dl in men. Nevel partial deficiency is defined as detectable but low immunoglobulin A, which is more than two standard deviations below normal.
Ig A deficiency is frequently associated with peripheral blood lymphocytes in normal B, CD 4 + and CD8 + normal and normal neutrophil and lymphocyte. IgA antibodies may be present. Peripheral blood may also be affected by autoimmune cytopenia. Conditions associated in some patients with deficiency of Ig A deficiency include one or more IgG immunoglobulin deficiency and response to pneumococcal immunization. Some patients with deficiency of Ig A late developing DIC.
IgA deficiency is always primary and below normal levels remained stable after 20 years of observation. Environmental factors such as drugs and infections can cause this problem, but is reversible in over half of cases.
The disease is more common in adults with chronic lung disease than those healthy. Studies show an increase of 3 times in childhood respiratory diseases, an increase of 4 times of severe respiratory diseases in adults, a similar increase in recurrent mild respiratory infections and recurrent viral infections specific growth. The study also showed a 4-fold increase in autoimmune diseases, an increase of 2.5 times the milk caused abdominal symptoms and a slight increase of atopic eczema, allergies to medications and food hypersensitivity.
Ig A deficiency has no specific therapy. Replacement therapy is not practical for the deficiency of Ig A short-lived due to Ig immunoglobulin A in commercial preparations. Antibiotic therapy is first line therapy, especially for respiratory and gastrointestinal infections. Immunization with pneumococcal vaccine is important, however not all patients can sustain an immune response. Prophylactic intravenous immunoglobulin in patients with Ig A deficiency is beneficial.
IgA deficiency complications include: severe anaphylactic reaction to blood products, bronchiectasis, recurrent infections sinopulmonare, chronic diarrhea, severe otitis media with hearing loss, malabsorption, malabsorption and growth retardation secondary chronic infection.
In children 6 months to 4 years the disease may be transient and resolve to permanently up to five years, in others the disease may progress. Adults with IgA deficiency are asymptomatic, yet 90% recurrent bacterial respiratory infections.
Signs and symptoms
Patients over 6 months of age who have upper respiratory infection with bacteria and encapsulated (H. influenzae, S. pneumoniae) should be evaluated for IgA deficiency. Patients with antibody deficiency usually do not have recurrent infections in the first months of life because it presents circulating immunoglobulins placental transfer of maternal immunoglobulin. Children and adults presenting with gastrointestinal tract infections, infections sinopulmonare.
Studies show that 90% of patients go this deficiency are asymptomatic. However, recent studies show that 80% of individuals with IgA deficiency develop symptoms later in life. Symptomatic patients have a history of recurrent otitis significant for average, sinusitis, bronchitis, gastrointestinal tract infections, pneumonia, severe allergic reactions after transfusion of blood or infusion of immunoglobulins, or children without seat.
Recurrent infections are the most common sinopulmonare manifestation associated with IgA deficiency. Most upper respiratory tract infection and lower viral pathogens are caused by features of community acquired pneumonia. Patients with IgG subclass deficiency concomitant type 2 are at increased risk for recurrent infections with S. pneumoniae, H. influenzae, M. catarrhalis or Staphylococcus aureus.
Gastrointestinal tract infections with viruses, bacteria and parasites Giardia lamblia is manifested by chronic diarrhea with or without malabsorption. Biopsy specimen shows nodular lymphoid hyperplasia with Vili swollen.
Laimente allergy atopic and other diseases such as allergic conjunctivitis, rhinitis, urticaria, atopic dermatitis and asthma are common in patients with IgA deficiency. Among patients with IgA deficiency 10-44% have anti-IgA antibodies and these patients may have severe adverse reactions in IgA-containing materials such as blood, plasma or immunoglobulin.
Physical examination. Patients have various signs of recurrent respiratory infections, including swelling, pain or tenderness and jaw front sinuses, runny nose, fever, productive cough and dyspnea or nonproductive. Description of the clinical picture of gastrointestinal damage include abdominal distension, focal tenderness to palpation directly, diffuse pain and increased peristalsis.
Complications of IgA deficiency include:
- Severe anaphylactic shock, the product of blood
- Bronchiectasis, recurrent infections sinopulmonare
- Chronic diarrhea and malabsorption
- Otitis media, severe hearing loss
- Secondary malabsorption, growth retardation and chronic infections.
Diagnosis
Laboratory studies:
- Almost all patients with IgA deficiency secretory IgA have loss of type 1 and 2 in external secretions
- Low levels of serum IgA in children between 6 months and 4 years should be confirmed to be persistently low at the age of 4 years before a diagnosis for life
The repeat tests of serum IgA for children under 5 years.
Imaging studies:
Chest radiography is performed with CT scan for the sinuses to investigate structural lesions or chronic disease and to assess bronchiectasis. Humoral immunodeficiency in patients with chronic productive cough primitive and high-resolution CT scan is performed to evaluate the extension of lung damage. Patients who are diagnosed with immunodeficiency after 45 years should be investigated for thymoma imaging.
Pulmonary function tests may show elements and obstructive pulmonary patients with IgA deficiency. Jejunal biopsy for patients with chronic diarrhea deficient5a IgA and malabsorption may look bloating Vili. IgM-secreting plasma cells are observed in the lamina propria, instead of cells secreting IgA. Lymph node architecture is normal.
Differential diagnosis is made with the following conditions: disorders of T cells and B combined, severe combined immunodeficiency, Wiskott-Aldrich syndrome, immunodeficiency drug, post infection.
Treatment
Treatment includes identifying comorbidities preventive measures to reduce the risk of infection and prompt treatment of infections.
Medical therapy
There is no specific therapy for IgA deficiency. Replacing therapy is not practical because of the IgA preparations short commercial life.
Antibiotic therapy is first-line therapy, specific to respiratory and gastrointestinal infections. Sinopulmonare associated infections are treated according to treatment protocols for community respiratory infections in healthy individuals.
Immunization with vaccine penumococic is important, however not all patients can sustain an immune response. IgG titres post-vaccination must be obtained to confirm the presence of a protective level of IgG pneumococcal near age.
Prophylaxis with immunoglobulin G was contraindicated in patients with IgA deficiency because of the risk of severe systemic side effects or development of anti-IgA. Reports today show that immunoglobulin is recommended for safe and effective prophylaxis, including patients with IgA antibodies.
Surgical therapy.
Some patients may require surgery to promote drainage of infection.