鼻腔內水蛭－－二例報告

EPISTAXIS DUE TO NASAL LEECH INFESTATION-2 CASE REPORTS

流鼻血（epistaxis） ，是許多人共同的經驗，常見原因大多是鼻黏膜受傷所致，常被人們所忽略。鼻內水蛭（leech） 的寄生，常見於較落後地區，在公共衛生進步的今日臺灣已少見。本文報告二個連續的病例，發生在2007年七月初，主訴皆為經常性流鼻血，病例一與二之生活史都有生飲山澗水或溪邊捧水洗臉之共同經驗。經由鼻內視鏡證實流鼻血為水蛭寄生所致，二例均以麻醉劑噴灑後順利將水蛭取出。水蛭又叫螞蝗，以吸人畜血為生，身體前後端各有一個吸盤。後端吸盤吸附於宿主黏膜上，以前端吸盤吸取宿主之血。水蛭之唾液中含有抗凝血劑，稱為水蛭素（hirudin） ，以及類組織胺化合物和多種局部麻醉劑，會使宿主之傷口流血不止，而且無感於傷口的疼痛，以至於延誤就醫。對於流鼻血的患者，特別是單側、經常性，又有接觸山澗溪水之生活經驗者，必須把鼻腔內水蛭寄生列為重要鑑別診斷之一，詳問其病史並以鼻纖維內視鏡仔細檢查整個鼻腔及咽、喉、氣管各處。

Infestation on the body surface by leeches is a common occurrence among humans living in tropical areas. Epistaxis due to a leech in the upper respiratory tract, although rare, has been known for centuries. This paper present two cases with a history of nasal obstruction, sensation of nasal movement and intermittent epistaxis for a further month in the nasal cavity. We found a leech in the nasal sinus ostium and on the nasal septum respectively by endoscopic examination. The leeches were easily removed by surgical forceps after 5 minutes of being sprayed with Xylocaine. Nasal leech infestation is usually through contact with fresh water containing leeches while drinking. washing or swimming. Although not usually life-threatening, such infestations can cause blood loss as well as physical and psychological discomfort. A high index of suspicion of leech infestation must be expected when faced with patients presenting nasal obstruction and epistaxis and a history of recent contact with fresh water streams or lakes.