【病 史】 本例為一名8歲的男孩,因 “臭脚"三個星期,由他父親帶來看我. 他父親發現男孩足底皮膚有異,但並不痕癢. 男孩雙足長時間患有多汗症. 【皮膚學檢查】皮損分佈於雙足受壓部位 – 主要是大趾(腹面),其次為其他脚趾的腹面以及前足受壓部. 皮損在角質層形成猶如火山口狀的凹陷.有些凹陷不融合,有些則互相融合,腐蝕大片角質層. 有些受累區域(如大趾腹面)的角質層完全水化(由於多汗症) 變成白色.
【診 斷】基於臨床表現.菌絲KOH制劑檢查陰性.伍德氏光檢查並不出現珊瑚紅螢光.有些醫生可能作細菌培養以排除S.aureus,GAS或P.aerugiosa感染.
【預 防】避免穿不透氣的鞋袜.用Benzoyl peroxide洗脚和消毒酒精gel外敷.
【治 療】 本病因微小球菌腐蝕角化增厚的皮膚引起.首先要治療雙足的多汗症和穿透氣的鞋. 洗澡後外塗 Benzoyl peroxide gel, 每日一次,共7天. 外用erythromycin或clindamycin溶液,每日二次,共7天. 外塗Fusidate或mupirocin葯膏. 外用抗真菌葯(clotrimazole,miconazole或econazole)也可能有效. 如局部治療無效,可服用抗生素Macrolide類或tetracycline,共7天.
Case History:
This was a 8 year old boy. He was brought to see my by his father. His father said the boy had 3 weeks history of foot odor. When he examine his boy’s feet, he found abnormal skin changes in his boy’s soles. The boy did not complain of itchiness of feet. He had a long history of hyperhidrosis of both feet.
Clinical findings:
On examination, the lesions were distributed on the pressure-bearing areas of his feet – mainly big toe (ventral aspect), also on the ventral aspect of other toes, and also on the pressure-bearing areas of the fore-foot. The skin lesions were crater-like pits in stratum corneum. Some of the pits remain discrete while some of them become confluent, forming large areas of eroded stratum corneum. Some of the involved areas (eg. ventral aspect of big toe) were white when stratum corneum was fully hydrated (due to hyperhidrosis).
Investigation:
Diagnosis was made based on the clinical findings. KOH preparation was negative for hyphae. Wood lamp examination did not show bright coral-red fluorescence. Some doctors might do culture to rule out S. aureus, or GAS or P. aeruginosa infections
Management:
This condition is caused by Kytococcus sedentarius which causes defects in thickly keratinized skin with eroded its of variable depth. Predisposition: Hyperhidrosis of feet and occlusive footwear.
To prevent the condition, patient is asked to avoid occlusive footwear. Wash with benzoyl peroxide and put on antiseptic alcohol gel.
Topical therapy: Benzoyl peroxide gel daily after showering for 7 days. Topical erthyromycin or clindamycin solution twice daily for 7 days. Fusidate ointment or mupirocin ointment or cream. Topical anti-fungal (eg. clotrimazole, miconazole or econazole) might also work.
If the topical therapy doesn’t work, we can start systemic antibiotic therapy : a Macrolide or a tetracycline for 7 days.
以下中文討論文章是從網絡中引用以供參考,並非翻譯英文原著,如有任何問題,應以英文版本為準。
醫學名稱:Pitted Keratolysis ; keratolysis plantare sulcatum;足蹠蠹蝕症;凹陷性角質溶解症;點狀角質層分離症
好發年齡:好發於容易有腳汗的患者,或是整天穿鞋流汗的運動員,腳經常處於泡濕的狀態者。
分佈部位:腳底承受身體重力的皮膚角質層,故多見於腳掌的前端與腳跟,還有與腳掌同面的腳趾頭,而不於腳趾縫發生。
致病原因:為細菌感染皮膚表層角質層所引起。病原菌大多是由棒狀桿菌屬(Corynebacterium 、actinomyces或Streptomyces)、Dermatophilus congolensis 或微小球菌(Micrococcus sedentarius (now renamed to Kytococcus sedentarius,))。這些細菌能製造與分泌蛋白質酵素溶解,破壞皮膚角質層,於是腳底皮膚出現肉眼可見的類似珊瑚礁或的像火山口凹洞;此外,因細菌分解角質蛋白中的硫,會散發類似阿摩尼亞味道,才導致散發惡臭。
症狀與特徵:大多數病患不覺得癢,僅少數有輕微的癢感,可能會覺得腳底黏黏的、有臭味,因此經常被忽略,除非很嚴重的腳臭使家人深感困擾,否則大部分的患者並不太想治療,大多都是被家人逼著來的。此病的特色是,可以於腳底腳底承受身體重力的皮膚處見到許許多多小小的,像火山口的凹洞分佈於腳底(最常見的典型臨床表現),有時彼此相連,甚或足底出現形成一大片白色潮濕、糜爛或脫皮症狀(常見於腳多汗的病人)。也因此,很容易與足癬(俗稱香港腳)搞混。當民眾自行買藥局複方的香港腳藥膏來擦,或是泡醋「殺菌」,常常會讓症狀更嚴重。
預防:預防方面就是盡量避免長時間穿鞋,常讓腳透氣,選擇透氣性較佳的鞋子,穿吸汗力強的棉襪,易流腳汗者除每日以香皂洗腳外,每周至少使用2次止汗劑,不要連續2天穿同一雙鞋,保持鞋內乾燥,避免與人共用鞋子、拖鞋,在游泳或下雨腳浸泡在水裡之後,要儘快將腳洗淨擦乾,保持足部的乾爽,以減少足蹠蠹蝕症的發生。
治療:治療上,主要是以殺菌的外用抗生素藥膏(erythromycin 或 clindamycin藥膏或benzoyl peroxide藥膏)合併止汗劑(20% aluminum chloride solution)為主,兩周內即可痊癒;極少的狀況下,才需要口服藥(erythromycin)。此外,最常用來治療香港腳的imidazole藥膏不僅抗黴菌,對於凹陷性角質溶解症也有效。
治療後
After a week’s medical treatment, there was significant improvement of the condition. However, recurrence was common because the boy had hyperhidrosis of feet and he needed to wear shoes/runners to school.
經過一個星期的治療,病情已經得到明顯的改善。縱使得到徹底的治療,但仍然有復發的可能性,因為大腳汗及長期穿著密封的鞋是復發的重要因素。
圖示經過一個星期治療後的雙足
主診醫生:鍾經略醫生
監督及指導機構 – 英國威爾斯大學/卡的夫大學臨床皮膚科專科部門
臨床皮膚科醫學照片版權所有,不得複製
膚科醫生常見皮膚問題 – 窩狀角質鬆解症, 足蹠蠹蝕症