靜脈注射人類免疫球蛋白 (IVIG)
**靜脈注射人類免疫球蛋白 (IVIG)** 是一種高濃度的生物製劑，由數千名人類血漿捐贈者中提取的免疫球蛋白（主要為 IgG）組成。 在獸醫學中，它主要作為一種昂貴的**標示外急救療法**，用於當傳統免疫抑制療法（如糖皮質激素或環孢素）失效時的嚴重、難治性免疫介導疾病。 **主要臨床應用：** * **原發性免疫介導性血小板減少症 (pIMT)：** 在獸醫研究中顯示出促進血小板快速恢復的最大潛力。 * **免疫介導性溶血性貧血 (IMHA)：** 用於難治性病例，儘管前瞻性研究顯示其在提高存活率方面的結果好壞參半。 * **免疫介導性皮膚病：** 例如多形性紅斑、史蒂芬斯-強森症候群 (SJS) 和中毒性表皮壞死鬆解症。 > **臨床要點：** 由於 IVIG 是人類血液製品，考慮到人類供應短缺的倫理問題、極高的藥物成本以及對外來蛋白質產生過敏反應的風險，其在獸醫學中的應用存在爭議。
作用機制: IVIG exerts complex immunomodulatory effects through multiple concurrent pathways rather than a single mechanism: * **Fc Receptor Blockade:** The massive influx of human IgG binds to and saturates **Fc receptors** on the patient's mononuclear phagocyte system (macrophages) → prevents the phagocytosis and destruction of the patient's own autoantibody-coated red blood cells or platelets. * **Anti-idiotypic Antibodies:** Contains antibodies that directly bind to and neutralize pathogenic autoantibodies. * **Cytokine Modulation:** Binds to and downregulates pathogenic cytokines including **Interleukin (IL)-1a**, **IL-6**, and **Tumor Necrosis Factor-alpha (TNF-α)**. * **Receptor Interference:** Binds to **CD5 receptors** and **T-cell receptors**, suppressing pathogenic T-cell and B-cell activation. * **Negative Feedback:** High circulating IgG levels provide negative feedback → downregulation of endogenous antibody production by B lymphocytes.
各物種劑量
- Immune-mediated diseases (IMHA, ITP) - General · 0.3-1.5 grams/kg · IV · varies · varies · Cost-benefit must be weighed carefully due to extreme expense.
- IMHA (refractory to conventional treatment) · 0.5-1.5 grams/kg · IV · once · over 12 hours
- Primary immune-mediated thrombocytopenia (pIMT) · 0.5 grams/kg · IV · single infusion
- Refractory erythema multiforme, Stevens-Johnson syndrome/toxic epidermal necrolysis, and other cutaneous adverse drug reactions · 0.5-1 gram/kg · IV · 1-2 times, 24 hours apart · over a 4-6 hour period; may need to be repeated for 3-4 days in a row · Uses a 5-6% solution.
劑量為持牌獸醫專業人員的臨床參考。請務必對照最新藥品說明書及個別病患確認。
給藥途徑
禁忌症
- Prior hypersensitivity reactions to human albumin or human blood products
不良反應
- Increased blood pressure
- Local injection site reactions (pain, tenderness)
- Anaphylaxis / Hypersensitivity reactions
- Volume overload (due to colloid-like properties)
- Thrombotic events
- Fever, chills, facial flushing, nausea (human data)
- Renal dysfunction / Acute renal failure (human data)
藥物相互作用
- Live Vaccines · IVIG may interfere with the immune response and efficacy of the vaccine due to passively transferred antibodies.
監測
- Vital signs (blood pressure, temperature, heart rate)
- Lung auscultation (to assess for pulmonary edema/volume overload)
- Renal function tests (BUN, Creatinine) and urine output
- Clinical efficacy (e.g., serial platelet counts, hematocrit, dermatological lesion resolution)
過量
Overdosage primarily increases the risk of **fluid volume overload** due to the colloid-like osmotic pull of the concentrated proteins. Other reactions could include severe pain and tenderness at the injection site, and potentially an increased risk of thrombotic events or renal impairment.
VetSheet 藥物參考供持牌獸醫專業人員作臨床決策輔助之用,不能取代專業判斷或廠方最新藥品說明書。