Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042109 (urticaria)
 6,569 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cutaneous eruptions related to hepatitis C virus (HCV), a major cause of hepatitis in the setting of blood transfusion, intravenous drug abuse, organ transplantation, and hemodialysis, are typically reported as isolated cases. We encountered 35 cases of HCV infection associated with cutaneous eruptions. The present study evaluates paraffin-embedded, formalin-fixed tissue sections stained with hematoxylin and eosin from biopsy specimens of skin lesions from 35 patients seropositive for HCV. In 20 cases, reverse transcriptase polymerase chain reaction (RT-PCR) was performed using a probe for HCV RNA; the RNA was detected through the action of alkaline phosphatase on the chromogen nitroblue tetrazolium and bromochloroindolyl phosphate. The clinical spectrum comprised dermatomyositis-like photodistributed eruptions, palpable purpura, folliculitis, violaceous and perniotic acral lesions, ulcers, nodules, and urticaria. Lesions were also classified histopathologically by the dominant reaction pattern: vasculopathies of neutrophilic, lymphocytic, and granulomatous vasculitis and pauci-inflammatory subtypes (15 patients); palisading granulomatous inflammation (3 patients); sterile neutrophilic folliculitis (5 patients); dermatitis herpetiformis (1 patient); lobular panniculitis composed of neutrophilic lobular panniculitis in 2 patients and benign cutaneous polyarteritis nodosa in 1 patient; neutrophilic dermatoses, including neutrophilic urticaria, neutrophilic eccrine hidradenitis, and pyoderma gangrenosum (3 patients); interface dermatitis (3 patients); and low-grade lymphoproliferative disease of B-cell lineage representing marginal zone lymphoma in 1 patient and a clonal plasmacellular infiltrate in another patient. In most cases, whereas 1 of the aforementioned disorders defined the dominant reaction pattern, there was an accompanying secondary reaction pattern, defining a hybrid picture. Endothelial changes including endothelial cell enlargement and effaced heterochromatin with margination of the chromatin to the nuclear membrane were seen in several cases; in some cases similar cytopathic changes also involved the supporting pericytes, eccrine ductular cells, or keratinocytes. The RT-PCR analyses in 8 of 20 cases examined revealed HCV RNA expression in a focal, weak fashion in endothelia and perivascular inflammatory cells in those cases showing vasculopathic changes. Viral parasitism of endothelia may be important in cutaneous lesional propagation in the setting of HCV infection. Cross-reactivity between endogenous and viral antigens, leading to cellular and/or type II immune reactions; viral tropism to B lymphocytes, resulting in B cell expansion with resultant autoantibody production; and circulating immune complexes containing monoclonal cryoglobulins may also be of pathogenetic importance. Tropism of the virus to B lymphocytes provides a mechanism for the development of low-grade clonal B cell lymphoproliferative disease in this setting.
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PMID:The dermatopathologic manifestations of hepatitis C infection: a clinical, histological, and molecular assessment of 35 cases. 1282 11

Rituximab is a chimeric monoclonal antibody that targets CD20 positive B cells and has a positive effect on both overall and progression-free survival in B-cell lymphoid malignancies. Combination rituximab with chemotherapy treatment provide survival improvement. Although rituximab is an important treatment option in hematological malignancies, the risk of allergic reactions is high. These reactions are usually IgE-mediated and can be varied in regard of severity from urticaria to anaphylaxis. It is an option to interrupt the treatment and ommit rituximab therapy who had allergic reactions. Drug desensitization is another option and successful results have been reported by applying desensitization to such reactions. Drug desensitization alters the immune response to induce a state of temporary clinical tolerance to the allergic drug by giving gradual increasing of doses of drug at fixed time intervals. Herein, we present 3 cases successfully treated with rituximab desensitization. The cases were using rituximab with the diagnosis of Burkitt lymphoma, follicular lymphoma, and marginal zone lymphoma, respectively. Two cases had grade 2 and 1 case had grade 3 systemic allergic reaction with rituximab. There was no known allergy history in all 3 cases. All patients tolerated the desensitization protocol. The subsequent treatments of the patients were also given by desensitization protocol. A total of 12 desensitizations were administered to 3 cases. No severe or life-threating reactions were observed in subsequent applications. To date applying desensitization protocols ensure rituximab treatment safely. Rituximab desensitization can be performed at trained allergy centers, and it may be an appropriate option for rituximab allergic patients.
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PMID:Rituximab desensitization in three patients with severe rituximab allergy. 2886 80