Heavy Chain Diseases

Heavy chain diseases are neoplastic plasma cell disorders, which are characterized by the overproduction of monoclonal immunoglobulin heavy chain. Symptoms, diagnosis and treatment vary depending on the specific disease.

The heavy chain diseases, there are usually malignant plasma cell diseases. In most plasma cell disorders Paraproteins structurally similar to the normal antibody molecules. In contrast, incomplete in heavy chain diseases monoclonal immunoglobulins (real Paraproteins) are formed. These consist only (from the heavy chain components either alpha [?] gamma [?], mu [?] or delta [?] no light chains (an epsilon [?] chains disease was not yet described) Most of the heavy chain proteins are fragments of their normal counterparts with internal deletions of variable length, resulting apparently from structural mutations. the clinical picture is more like lymphoma than the multiple myeloma. heavy chain diseases are suspected lymphoproliferative diseases in patients with clinical signs.

Heavy chain diseases are neoplastic plasma cell disorders, which are characterized by the overproduction of monoclonal immunoglobulin heavy chain. Symptoms, diagnosis and treatment vary depending on the specific disease. The heavy chain diseases, there are usually malignant plasma cell diseases. In most plasma cell disorders Paraproteins structurally similar to the normal antibody molecules. In contrast, incomplete in heavy chain diseases monoclonal immunoglobulins (real Paraproteins) are formed. These consist only (from the heavy chain components either alpha [?] gamma [?], mu [?] or delta [?] no light chains (an epsilon [?] chains disease was not yet described) Most of the heavy chain proteins are fragments of their normal counterparts with internal deletions of variable length, resulting apparently from structural mutations. the clinical picture is more similar to lymphoma than multiple myeloma. heavy chain diseases are suspected in patients with clinical signs of lymphoproliferative disease. IgA heavy chain disease (alpha-chain disease) the IgA heavy chain disease is the most common heavy chain disease. It is similar to Mediterranean lymphoma (immunoproliferative small bowel diseases). the IgA heavy chain disease usually occurs between 10 and 30 years and can be found geographically clustered in the middle East. cause may be an aberrant immune response to parasites and other microorganisms. Usually, a villous atrophy and plasma cell infiltration of the jejunal mucosa and occasional infiltration mesenteric lymph nodes found. Peripheral lymph nodes, bone marrow, liver and spleen are not usually involved. An involvement of the respiratory tract occurs only rarely. Osteolytic lesions do not occur. Almost all patients present with diffuse abdominal lymphoma and malabsorption. The blood image can anemia, leukopenia, thrombocytopenia, eosinophilia and circulating atypical lymphocytes or plasma cells have. Serum protein electrophoresis is normal in half of the cases; often there is an increased ?2 – and ? (beta) fraction or a reduced ? fraction. For diagnosis, the detection of a monoclonal alpha chain in the immunofixation electrophoresis is necessary. This chain is sometimes found in concentrated urine. If it can not be detected in serum or urine, a biopsy is necessary. The abnormal protein is sometimes detectable in intestinal secretions. The intestinal cellular infiltrate may be pleomorphic and not obviously malignant. A Bence Jones proteinuria is missing. The course is highly variable: some patients die within 1-2 years, while others – especially after treatment with corticosteroids, cytotoxic drugs, and broad-spectrum antibiotics – many years experience lasting remissions. IgG heavy chain disease (Gamma-chain disease) IgG heavy chain disease usually resembles an aggressive malignant lymphoma is occasionally asymptomatic and benign. The IgG heavy chain disease occurs primarily in older men, but can also occur in children. Accompanying chronic diseases include rheumatoid arthritis, Sjögren’s syndrome, SLE, tuberculosis, myasthenia gravis, hypereosinophilic syndrome, autoimmune hemolytic anemia and thyroiditis. There is a decrease of normal immunoglobulin levels. Lytic bone lesions are atypical. Occasionally, amyloidosis developed. Common manifestations include lymphadenopathy and hepatosplenomegaly, fever and recurrent infections. A Gaumenödem occurs in about a quarter of patients. The blood image can anemia, leukopenia, thrombocytopenia, eosinophilia and circulating atypical lymphocytes or plasma cells have. Diagnosis requires the detection of monoclonal IgG heavy chain fragments in serum and urine by immunofixation. Of the affected patients, the half monoclonal serum fractions of> 1 g / dl (often broad and heterogeneous) and the other half proteinuria> 1 g / 24 h. Although the heavy chain proteins can include all IgG subclasses, the G3 subclass is particularly common. Bone marrow or lymph node biopsies are performed when other tests are not diagnostic groundbreaking show different histopathology. The median survival for aggressive disease is about 1 year. Death usually occurs as a result of bacterial infection or progressive malignancy. Temporary remissions can be achieved with alkylating agents, vincristine or corticosteroids and radiotherapy. IgM heavy chain disease (Mu chain disease) The rare IgM heavy chain disease causes a clinical picture that resembles chronic lymphocytic leukemia or other lymphoproliferative diseases. The IgM heavy chain disease usually affects adults> 50 years. An organ involvement (spleen, liver, abdominal lymph nodes) is typically, but not an extended peripheral lymphadenopathy. Pathological fractures and amyloidosis can occur. Serum protein electrophoresis is usually inconspicuous or shows a hypogammaglobulinemia. A Bence Jones proteinuria (type ?) is found in 10-15% of cases. The blood image can anemia, leukopenia, thrombocytopenia, eosinophilia and circulating atypical lymphocytes or plasma cells have. The diagnosis usually requires a bone marrow examination; vacuolated plasma cells of the patient are observed at two-thirds and, if present, almost pathognomonic. Death can occur within a few months or many years. Common cause of death is the uncontrollable proliferation of chronic lymphocytic leukemia cells. The treatment depends on the patient’s condition and may include alkylating agents plus corticosteroids or be based on the treatment of proliferative disorder, which it most closely resembles.

Health Life Media Team

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