Urticaria pigmentosa - 色素性蕁麻疹
色素性蕁麻疹 (Urticaria pigmentosa) 是皮膚肥大細胞增多症最常見的形式。這是一種罕見疾病，由皮膚中過多的肥大細胞引起，受到刺激時會在皮膚上產生蕁麻疹或病變。皮膚常出現紅色或棕色斑點，主要分布於胸部、前額及背部。這些肥大細胞在受到刺激（例如摩擦皮膚、受熱）時會釋放過量組織胺，誘發過敏反應，使刺激部位出現蕁麻疹，亦稱「達裡爾氏徵」。
relevance score : -100.0%
ReferencesMastocytosis 是一種肥大細胞過多的病症，通常存在於皮膚、骨髓和消化系統等身體各部位。根據世界衛生組織 (WHO) 的說法，cutaneous mastocytosis 可分為三種主要類型。第一類（mastocytomas）由孤立或少數（≤3）個病變組成。第二種（urticaria pigmentosa）涉及多個病變，範圍通常從 10 多個到不到 100 個。Urticaria pigmentosa 是兒童皮膚肥大細胞增多症最常見的形式，但也可能發生在成人身上。這通常是一種無害的病症，往往在青春期期間得到改善。與成人肥大細胞增多症不同，urticaria pigmentosa 很少影響內臟器官。Urticaria pigmentosa 的一個顯著特徵是容易在皮膚上出現小、發癢、紅棕色或黃棕色的斑點或病變，通常稱為蕁麻疹。這些斑點多在童年出現，且可能持續一生。
Mastocytosis is a disorder characterized by mast cell accumulation, commonly in the skin, bone marrow, gastrointestinal (GI) tract, liver, spleen, and lymphatic tissues. The World Health Organization (WHO) divides cutaneous mastocytosis into 3 main presentations. The first has solitary or few (≤3) lesions called mastocytomas. The second, urticaria pigmentosa (UP), involves multiple lesions ranging from >10 to <100 lesions. The last presentation involves diffuse cutaneous involvement. UP is the most common cutaneous mastocytosis in children, but it can form in adults as well. It is considered a benign, self-resolving condition that often remits in adolescence. Unlike adult forms of mastocytosis, there is rarely any internal organ involvement in UP. What makes UP particularly distinctive is its tendency to manifest as small, itchy, reddish-brown, or yellowish-brown spots or lesions on the skin, commonly referred to as urticaria or hives. These spots typically appear in childhood and can persist throughout a person's life.
Mastocytosis is a disorder characterized by mast cell accumulation, commonly in the skin, bone marrow, gastrointestinal (GI) tract, liver, spleen, and lymphatic tissues. The World Health Organization (WHO) divides cutaneous mastocytosis into 3 main presentations. The first has solitary or few (≤3) lesions called mastocytomas. The second, urticaria pigmentosa (UP), involves multiple lesions ranging from >10 to <100 lesions. The last presentation involves diffuse cutaneous involvement. UP is the most common cutaneous mastocytosis in children, but it can form in adults as well. It is considered a benign, self-resolving condition that often remits in adolescence. Unlike adult forms of mastocytosis, there is rarely any internal organ involvement in UP. What makes UP particularly distinctive is its tendency to manifest as small, itchy, reddish-brown, or yellowish-brown spots or lesions on the skin, commonly referred to as urticaria or hives. These spots typically appear in childhood and can persist throughout a person's life.
一名 6 歲女孩前來就診，身上出現了幾個深色斑點，這些斑點最初出現在頭皮，之後在過去六個月內擴散至臉部和身體。她提到，受到壓力時，斑點會升高、發紅、發癢。她沒有潮紅、嘔吐、腹瀉或喘息等症狀，個人及家族病史亦未提供相關線索。檢查發現，她的頭皮、額頭、臉部與頸部有多處黑斑，胸部和背部則有輕微凸起的黑斑。輕輕摩擦斑點約 2 分鐘即會腫脹並發癢，但症狀於 15‑20 分鐘內自行消失 (Darier's sign)。
A 6-year-old female, presented with multiple dark-colored lesions, which started over the scalp and further progressed to involve the face and trunk since past six months. She gave a history of elevation, redness, and itching on the lesions on application of pressure. There was no associated flushing, vomiting, diarrhoea, or wheeze. The personal and family history was not contributory. On examination, there were multiple hyperpigmented macules over the scalp, forehead, face, and neck in addition to minimally elevated hyperpigmented plaques over the chest and the back. Gentle rubbing of the lesions elicited urtication and itching within 2 min and it resolved within 15–20 minutes, suggestive of the Darier's sign.
A 6-year-old female, presented with multiple dark-colored lesions, which started over the scalp and further progressed to involve the face and trunk since past six months. She gave a history of elevation, redness, and itching on the lesions on application of pressure. There was no associated flushing, vomiting, diarrhoea, or wheeze. The personal and family history was not contributory. On examination, there were multiple hyperpigmented macules over the scalp, forehead, face, and neck in addition to minimally elevated hyperpigmented plaques over the chest and the back. Gentle rubbing of the lesions elicited urtication and itching within 2 min and it resolved within 15–20 minutes, suggestive of the Darier's sign.
