Angioimmunoblastic lymphadenopathy

Introduction

Introduction to angioimmunoblastic lymphadenopathy

Angioimmunoblastic lymphadenopathy (AILD) is a disease in which the regulation of T lymphocytes with unknown etiology is abnormal, resulting in excessive proliferation of B lymphocytes after antigen activation.

basic knowledge

The proportion of illness: 0.001%

Susceptible people: no specific population

Mode of infection: non-infectious

Complications: pleural effusion

Pathogen

Causes of vascular immunoblastic lymphadenopathy

(1) Causes of the disease

The cause of AILD has not yet been fully elucidated, and viral infections and drug allergies are considered to be possible causes.

1. About one-third of drug allergies have a history of drug exposure. Common drugs include penicillins, anticonvulsants, oral hypoglycemic agents, antipyretic analgesics, sulfonamides, aminoglycosides, antiepileptic drugs and Vaccination, etc., suggests that antigen stimulation has a triggering effect.

2. Virus infection In some patients, the EBV antibody titer increased. It has been reported that the detection rate of EBV-DNA in AILD and related diseases is as high as 84% to 97%. It is also reported that there are rubella virus antigens in the lymph nodes of 14 patients. The disease is associated with a viral infection.

3. Collagen disease This disease has benign lymph node hyperplasia and autoantibody production, which has the characteristics common to certain non-specific autoimmune diseases. Therefore, collagen disease may be related to the pathogenesis of this disease, mainly in systemic lupus erythematosus (SLE). , rheumatoid arthritis and Sjogren's syndrome (sjogren's syndrome).

(two) pathogenesis

Experimental studies have shown that patient T cells can strongly stimulate B cells, promote B cell proliferation and produce immunoglobulins. Most of these T cells express HLA-DR antigen, and lymph node infiltrating cells are mainly T cells, and their immune phenotype and mature T The cells are the same, CD4 cells are more than CD8 cells. These T cells also express IL-2 receptor, which can be recognized by antigens such as CD25 and HLA-DR. In peripheral blood, the percentage of T cells is reduced, and most of them are activated HLA-DR ( Cells, cells of the mononuclear macrophage cell line increased significantly, and most of the B cells were normal.

Prevention

Angioimmunoblastic lymphadenopathy prevention

18% can be converted to large cell lymphoma.

Complication

Vascular immunoblastic lymphadenopathy complications Complications pleural effusion

Can be complicated by respiratory symptoms, pleural effusion, lung parenchymal infiltration, hilar mediastinal lymphadenopathy.

Symptom

Symptoms of angioimmunoblastic lymphadenopathy Common symptoms Night sweats, hypothermia, anemia, leukocytosis, hyperthermia, lymphadenopathy, eosinophilia, weight loss, joint swelling and pain

1. Fever, anorexia, hyperhidrosis, weight loss and other symptoms, 65% of patients have fever, can be low fever or persistent high fever, 50% of patients with night sweats, about 50% of patients may have weight loss, often onset anxious.

2. Superficial and/or deep lymphadenopathy often accompanied by liver, spleen to moderate swelling, a few cases of interstitial pneumonia, multiple radiculitis, muscle weakness, ENT lesions, etc., lymphadenopathy can be Very significant, very common (98%), maximum diameter up to 8cm or only slightly enlarged, can be reduced or intermittent.

3. The history of drug allergies and/or the onset of rash in about 1/3 of cases and the occurrence of rash are related to temporary drug exposure.

Examine

Examination of angioimmunoblastic lymphadenopathy

1. Polyclonal hyperimmune globulinemia is an increase in IgG and IgM, occasionally cryoglobulinemia, in addition to decreased levels of complement, increased ESR.

2. Coombs test autoantibodies, hemoglobin and platelets are often reduced, a small number of patients with reticulocytes increased, individual patients with peripheral blood visible plasma cells, primitive plasma cells and immunoblasts, more common in patients with severe AILD.

3. Pathological features The normal structure of the lymph nodes is destroyed, and the lymphatic follicles in the germinal center are absent. The following "triple signs" appear.

(1) A large number of immunoblasts proliferate, with plasma cells, lymphocytes, eosinophils and histiocytosis.

(2) Dendritic small blood vessels are obviously proliferated with vascular endothelial swelling.

(3) The deposition of eosinophils in the interstitial, positive staining of PAS and acid mucopolysaccharide, it is generally believed that the deposition of amorphous acidic substances is not a diagnostic criterion.

According to clinical manifestations, symptoms, signs, chest X-ray, CT, B-ultrasound, etc.

Diagnosis

Diagnosis and identification of vascular immunoblastic lymphadenopathy

Diagnostic criteria

The diagnosis of this disease is relatively difficult. It is difficult to distinguish from other lymphadenopathy including reactive lymphadenopathy, malignant lymphoma, malignant histiocytosis, etc. from clinical or pathological perspective, but from a clinical perspective. There are still some clues to follow, and AILD should be considered when any of the following phenomena occur.

1. Older patients, mostly in the short period of 40 years old, fever, rash and general malaise, joint swelling and pain, a few with interstitial pneumonia, multiple radiculitis, muscle weakness.

2. The lymph nodes are mild or significantly enlarged. The diameter of the literature is up to 8cm, and some have autoimmune diseases.

3. Laboratory tests may have anemia, coombs test positive, leukocytosis at initial diagnosis, occasional eosinophilia, platelet and lymphocyte reduction, serological examination suggesting polyclonal hypergammaglobulinemia, mainly: IgG Increased IgM may have cryoglobulinemia; complement consumption, autoantibody formation, erythrocyte sedimentation rate, and early lymph node biopsy. If there is a typical "triple syndrome", the diagnosis can be confirmed. The differential diagnosis also depends on the diagnosis. Pathological examination results, domestic and foreign authors have emphasized the importance of multiple lymph node biopsy. Although liver, spleen, bone marrow and skin often have similar changes, they are not as typical as lymph node changes.

Any of the first, second, and third items of the above-mentioned clinical manifestations with laboratory tests are important clues for the diagnosis of AILD, and the triad of lymph node pathology is a prerequisite for establishing a diagnosis.

Differential diagnosis

1. Castleman's disease is a rare and unexplained lymphoid tissue proliferative disease that should be differentiated from AILD.

2. Non-Hodgkin's lymphoma (NHL) and AILD are reliably identified by lymph node pathology. NHL generally has lymph node structure destruction, and there is a single lymphoma cell infiltration without the "triad" characteristic of AILD. Angioimmunoblast proliferation, dendritic vascular proliferation and/or deposition of eosinophils in the stroma.

Angioimmunoblastic T-cell lymphoma (AITCL) is one of the most common types of T-cell lymphoma in NHL. More and more experiments have found that there is a rearrangement of clonal TCR genes in AILD, so AIDD is considered AITCL, but there is no consensus yet. Some scholars disagree with this view. They believe that the prognosis of AITCL is better, so the two should be distinguished. The clinical manifestations of AITCL are very similar to AIDD, which is more common in the elderly and more common in men. There may be systemic lymphadenopathy, fever, weight loss, rash and polyclonal hypergammaglobulinemia. The identification of the two depends mainly on pathology. For example, if a transparent T cell infiltration occurs on the background of AILD, it should be diagnosed. For AITCL, if the TCR gene has a clonal rearrangement, it should be diagnosed as AITCL.

3. Tissue necrotic lymphadenitis (Kikuchi disease) is a non-suppurative inflammation of lymph nodes that may be caused by viral infection. It is more common in young women. The main clinical manifestations are fever, swollen lymph nodes, lymph node tenderness, often accompanied by leukopenia. Some patients may also have hepatosplenomegaly and rash, which is a self-limiting benign lesion. Because of the similar clinical manifestations with AILD, both need to be identified.