23.有關兒童特發性血小板低下性紫斑症（idiopathic thrombocytopenic purpura）的敘述，下列何 者最不適當？
(A)約有2至3成的病童會發生腦出血
(B)約7至8成的病童，會在6個月內血小板數目恢復正常
(C)青春期的女生，需注意是否有全身性紅斑性狼瘡（systemic lupus erythematosus）的可能
(D)家屬常會敘述孩童前一天完全正常，隔天身上就到處是出血點和瘀青

有關兒童特發性血小板低下性紫斑症（idiopathic thrombocytopenic purpura）的敘述，下列何 者最不適當？

(A) 約有2至3成的病童會發生腦出血

(B) 約7至8成的病童，會在6個月內血小板數目恢復正常

(C) 青春期的女生，需注意是否有全身性紅斑性狼瘡（systemic lupus erythematosus）的可能

(D) 家屬常會敘述孩童前一天完全正常，隔天身上就到處是出血點和瘀青

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答案是 (A) 約有2至3成的病童會發生腦出血，這個敘述是最不適當的。

兒童特發性血小板低下性紫斑症（ITP）的腦出血（顱內出血，ICH）發生率極低，約為0.2-1%，遠低於題目所述的20-30%。這是ITP罕見但最嚴重的併發症。

各選項分析：

(A) 錯誤 - 腦出血發生率僅約0.2-1%，而非20-30%。一項系統性回顧顯示兒童ITP的ICH加權發生率為1.0%（95% CI 0.4-1.9%）。另一項大型研究報告20年間4340名兒童ITP患者中僅25例（0.63%）發生ICH。美國調查估計ICH發生率為0.19-0.78%。雖然罕見，但ICH死亡率高達25%，另有25%會有神經後遺症。[1][2][3]

(B) 正確 - 約70-80%的病童會在6-12個月內自發緩解。研究顯示66%的兒童在3個月內恢復，37%在28天至6個月間緩解，16%在6-12個月間緩解。大多數兒童ITP預後良好，自然病程呈良性。[4][5][6]

(C) 正確 - 青春期女性需注意全身性紅斑性狼瘡（SLE）的可能。研究顯示15.4%的慢性ITP患者發展為SLE，持續ANA陽性是預後不良的指標。女性、年齡較大、無前驅感染、隱匿發病都是發展為慢性ITP的危險因子，而慢性ITP與SLE的關聯性需要警覺。[7][8]

(D) 正確 - 急性發病是兒童ITP的典型表現。許多兒童在前驅病毒感染後急性發病，家屬常描述孩童前一天完全正常，隔天突然出現廣泛性瘀點和瘀青。這種急性發病（相對於隱匿發病）反而預後較好，較不易發展為慢性ITP。[4][8]

臨床要點：

- ICH危險因子：血小板<10-20×10⁹/L（90%的ICH發生在此範圍）、頭部外傷（33%）、血尿（22.5%）[2][3]

- 45%的ICH發生在診斷後7天內，30%發生在慢性ITP階段[3]

- 大多數兒童ITP預後良好，約25.9%發展為慢性ITP[4]


Figure 2 Probability of remission in patients with chronic ITP by platelet level at diagnosis of chronic ITP Chotsampancharoen T, Sripornsawan P, Duangchoo S, Wongchanchailert M, McNeil E. Clinical Outcome of Childhood Chronic Immune Thrombocytopenia: A 38-Year Experience From a Single Tertiary Center in Thailand. Pediatric Blood & Cancer. 2017;64(11). doi:10.1002/pbc.26598. Figure 1 Patient enrollment, follow‐up, and ITP outcome Note : Lost to follow‐up indicates patients who did not have subsequent visits. Bennett CM, Neunert C, Grace RF, et al. Predictors of Remission in Children With Newly Diagnosed Immune Thrombocytopenia: Data From the Intercontinental Cooperative ITP Study Group Registry II Participants. Pediatric Blood & Cancer. 2018;65(1). doi:10.1002/pbc.26736.

References

1. Acute Stroke in Children With Immune Thrombocytopenia: A Systematic Review and Meta-Analysis. Ly A, Ahmad SA, Liu O, et al. British Journal of Haematology. 2025;206(5):1450-1457. doi:10.1111/bjh.20105.
2. Intracranial Hemorrhage in Primary Immune Thrombocytopenia (ITP): 20 years' Experience in Pediatrics. Elalfy MS, Eltonbary KYEM, El Ghamry IR, et al. European Journal of Pediatrics. 2021;180(5):1545-1552. doi:10.1007/s00431-020-03923-x.
3. Intracranial Hemorrhage (ICH) in Children With Immune Thrombocytopenia (ITP): Study of 40 Cases. Psaila B, Petrovic A, Page LK, et al. Blood. 2009;114(23):4777-83. doi:10.1182/blood-2009-04-215525.
4. Immune Thrombocytopenia in Finnish Children and Adolescents: A Population-Based Cohort Study. Kulmala LM, Aarnivala H, Pokka T, et al. Acta Paediatrica (Oslo, Norway : 1992). 2025;. doi:10.1111/apa.70090.
5. Bleeding Manifestations and Management of Children With Persistent and Chronic Immune Thrombocytopenia: Data From the Intercontinental Cooperative ITP Study Group (ICIS). Neunert CE, Buchanan GR, Imbach P, et al. Blood. 2013;121(22):4457-62. doi:10.1182/blood-2012-12-466375.
6. Eltrombopag for Newly Diagnosed Pediatric Immune Thrombocytopenia Requiring Treatment. Shimano KA, Grimes AB, Kaicker S, et al. JAMA. 2025;:2840458. doi:10.1001/jama.2025.18168.
7. Predictors for Spontaneous Remission in Childhood Chronic Immune Thrombocytopenia. Yang YN, Yeh YH, Chen JS, et al. Annals of Hematology. 2024;:10.1007/s00277-024-06056-5. doi:10.1007/s00277-024-06056-5.
8. Clinical and Laboratory Predictors of Chronic Immune Thrombocytopenia in Children: A Systematic Review and Meta-Analysis. Heitink-Pollé KM, Nijsten J, Boonacker CW, de Haas M, Bruin MC. Blood. 2014;124(22):3295-307. doi:10.1182/blood-2014-04-570127.
9. Clinical outcome of childhood chronic immune thrombocytopenia: A 38‐year experience from a single tertiary center in Thailand. Chotsampancharoen T, Sripornsawan P, Duangchoo S, Wongchanchailert M, McNeil E. Pediatric Blood & Cancer. 2017;64(11). doi:10.1002/pbc.26598.
10. Predictors of remission in children with newly diagnosed immune thrombocytopenia: Data from the Intercontinental Cooperative ITP Study Group Registry II participants. Bennett CM, Neunert C, Grace RF, et al. Pediatric Blood & Cancer. 2018;65(1). doi:10.1002/pbc.26736.