皮肤与性病学-授课教案:第四次课 药疹、带状疱疹、疥疮

课程名称

皮肤性病学

年级

05本

专业、层次

临床医学及专业方向

授课教师

许飏

职称

副教授

课型（大、小)

大

学时

3

授课题目（章、节)

药疹、带状疱疹、疥疮

基本教材或主要参考书

陈德宇，主编. 中西医结合皮肤性病学. 北京：中国中医药出版社. 2004

徐世正主译. 安德鲁斯临床皮肤病学. 北京：科学出版社. 2004

教学目的与要求：

目的：认识和掌握药疹的定义、病因病机、诊断和鉴别诊断以及治疗和预防原则。

认识和掌握带状疱疹、疥疮的病因、诊断和鉴别诊断以及治疗原则。

要求：掌握引起药疹的常见药物种类和临床表现；

1. 掌握重症药疹的治疗原则。

2.   掌握带状疱疹、疥疮的临床表现和诊断、治疗原则。

大体内容与时间安排，教学方法：

内容：复习、概括总论的知识要点，比较总论、各论学习方法的异同  5分钟

药疹的定义、发病机理、变态反应性药疹的特点   25分钟

药疹的临床表现、诊断和鉴别诊断   30分钟

药疹的治疗原则和预防    20分钟

带状疱疹的病因病机、临床表现和诊断、治疗原则    20分钟

疥疮的病因病机、临床表现和诊断、治疗原则  15分钟

小结   5分钟

方法：运用启发式、讨论式等多种教学方法简要复习、概括总论的知识要点，比较总论、各论学习方法的异同。恰当开展病案式教学及双语教学，以大量图片、简表对比加深感性认识。布置一些内容自学，弥补教学学时减少的不足。

教学重点、难点：

重点： 药疹的定义、病因病机；

药疹、带状疱疹、疥疮的临床表现；

药疹、带状疱疹的诊断；变态反应性药疹的特点

难点： 药疹的临床表现及鉴别诊断、重症药疹的治疗原则

教研室审阅意见：

教研室主任签名：

   年   月 日

基本内容

教学手段

课堂设计和时间安排

运用启发式、讨论式等多种教学方法简要复习、概括总论的知识要点，比较总论、各论学习方法的异同，起到承前启后的作用。

Drug eruption

药疹(drug eruption)亦称药物性皮炎(dermatitis medicamentosa)，是药物通过内服、注射、吸入、灌肠、栓剂使用，甚至通过破损皮肤等途径进入人体后，在皮肤粘膜上引起的炎症性皮疹，严重者尚可累及机体的其他系统。

由药物引起的非治疗性反应，统称为药物反应，药疹仅是其中的一种表现形式。

发病率Frequency:

• In the US: Drug eruptions occur in approximately 2-5% of inpatients（住院病人) and in more than 1% of outpatients（门诊病人).

• Internationally: Drug eruptions occur in approximately 2-3% of inpatients.

死亡率Mortality:

Most drug eruptions are mild, self-limited and usually resolve after the offending agent has been discontinued.

Severe and potentially life-threatening eruptions occur in approximately 1 in 1000 hospital patients. Mortality rates for erythema multiforme (EM) major are significantly higher. Stevens-Johnson syndrome (SJS) has a mortality rate below 5%, whereas the rate for TEN approaches 20-30%; most patients die from sepsis.

一、 病因:

1.个体因素 2.药物因素

All prescription（处方药) and over-the-counter（OTC非处方药)drugs including topical agents, vitamins, and herbal and homeopathic remedies

临床上易引起药疹的药物有：

①  抗生素

② 解热镇痛类

③ 镇静催眠药及抗癫痫药

④ 异种血清制剂及疫苗等

⑤  中药

二、发病机制Pathophysiology:：

1.  免疫性反应

immunologically mediated reactions

2.非免疫性反应两大类。

nonimmunologically mediated reactions.

Immunologically mediated reactions

Coombs and Gell proposed 4 types of immunologically mediated reactions, as follows:

• Type I is immunoglobulin E (IgE)–dependent reactions, which result in urticaria, angioedema, and anaphylaxis.
• Type II is cytotoxic reactions, which result in hemolysis and purpura.
• Type III is immune complex reactions, which result in vasculitis, serum sickness, and urticaria.
• Type IV is delayed-type reactions with cell-mediated hypersensitivity, which result in contact dermatitis, exanthematous reactions, and photoallergic reactions.

变态反应性药疹的特点：

只发生于少数过敏体质的服药者

皮疹的轻重与药理及毒理作用无关

有一定的潜伏期

皮疹形态各异

交叉过敏及多价过敏现象

停止致敏药物，糖皮质激素治疗常有效。

三、临床表现：

Although most drug eruptions are exanthematous, different types 医学.全在线www.med126.comof drug eruptions exist.

With every drug eruption, it is important to evaluate for certain clinical features that may indicate a severe potentially life-threatening drug reaction, such as TEN or hypersensitivity syndrome. Such features include the following:

• Mucous membrane erosions
• Blisters (Blisters herald a severe drugeruption.)
• Nikolsky sign (epidermis sloughs off withlateral pressure)
• Confluent erythema
• Angioedema and tongue swelling
• Palpable purpura
• Skin necrosis
• Lymphadenopathy
• High fever, dyspnea, or hypotension

药疹的临床表现多种多样

1． 固定型药疹Fixed drug eruptions

2． 荨麻疹型药疹Urticarial

3． 麻疹样或猩红热样药疹Morbilliform or exanthematous

4． 湿疹型药疹

5． 紫癜型药疹

6． 多形红斑型药疹EM - Includes a spectrum of diseases, eg, EM minor and EM major; many categorize SJS (10% of the skin)and TEN(30% or more the total body surface area) as EM major and differentiate them by body-surface involvement

7． 大疱性表皮松解型药疹

8． 剥脱性皮炎型药疹Erythroderma

四、诊断及鉴别诊断：

诊断可依据：

①有明确的服药史；

②有一定的潜伏期；

③除固定型药疹外，皮疹多对称分布，颜色鲜红；

④瘙痒明显；

⑤排除与皮损相似的其它皮肤病及发疹性传染病。

鉴别诊断：

①麻疹或猩红热相鉴别

②金葡菌性烫伤样皮肤综合征相鉴别。

③生殖器疱疹、硬下疳等鉴别。

五、治疗：

原则：

①停用一切可疑致敏药物及结构相似药物；

②加速致敏药物的排出；

③对症治疗已经出现的皮损和症状；

④注意药物的交叉过敏或多价过敏。

⑤预防药疹的再次发生。

重型药疹  应及时抢救，防止病情加重，减少并发症及后遗症，加强护理，缩短病程，降低死亡率。原则：

①及早足量使用糖皮质激素；

②预防和治疗感染及并发症；

③加强支持疗法；

④加强护理及局部治疗。

六、预防：

对比

案例式教学

简要复习变态反应类型及规律

举例说明

图片和病例

结合病例

举例说明

图片对比

（★－重点，☆－难点，)

5分钟

★概念

强调：药疹的给药途径，

突出与接触性皮炎概念的区别。

★举例描述皮损特征，说明药疹临床表现的多样性。指出：临床上使用频繁的药物引发药疹的几率更大。

★强调：绝大多数药疹是通过变态反应机制发生的，变态反应性药疹特点是绝大多数药疹的特点，也是重要的诊断依据。

★强调：变态反应性药疹

的潜伏期、多价过敏现象

是诊断治疗的重要方面

25分钟

★☆结合图片和病例形象具体地突出各型药疹临床表现的特征。

30分钟

★结合变态反应性药疹的特点容易掌握药疹的诊断依据。

★☆强调与皮损相似的其它皮肤病的鉴别是药疹的诊断依据之一。

★☆强调药疹是变态反应性疾病、医源性疾病，

联系大面积烫伤病人治疗护理特点说明重症药疹的治疗护理原则。

20分钟

基本内容

教学手段

课堂设计和时间安排

病毒性皮肤病

病毒可分为脱氧核糖核酸（DNA)病毒和核糖核酸（RNA)病毒两大类。根据病毒性皮肤病的不同临床表现特点，可将其分为3型：

1．新生物型2．疱疹型3．红斑发疹型

Shingles (Herpes Zoster)

Shingles (otherwise known as Herpes Zoster) is a painful, blistering rash caused by the chickenpox (varicella) virus, which affects only a limited area of skin, and makes you feel surprisingly tired, run down, and even depressed.

水痘(varicella)和带状疱疹（Herpes zoster)是由同一病毒即水痘-带状疱疹病毒(varicella- zoster virus, VZV)引起的两种不同的疾病。水痘是一种以散在分布的水疱为特征、传染性很强的疾病，多见于儿童。带状疱疹以群集小水疱沿神经走向单侧分布，伴明显神经痛为特征，多见于成人，中医称为缠腰火丹。

一、病因Causes

You can only get shingles (Herpes Zoster) if you have previously had chickenpox. After having chickenpox the virus lies dormant in the nerves, and shingles occurs when it is revitalised in one particular nerve to the skin, thus explaining the way it affects a clearly demarcated band of skin only.

Usually the cause is a decrease in your body"s natural resistance, which may come through other infections, stress, being generally run down, or occasionally, when the body"s immune defences are affected by certain drugs or other immune deficiencies.

病原体为水痘-带状疱疹病毒。具嗜神经和皮肤的特性。

三、临床表现

1.现全身或局部前驱症状1日～4日后，皮肤出现群集的小水疱或丘疱疹。疱液澄清或血疱，沿神经走向呈带状排列，基底常绕以红晕。一般不超过躯干中线。

2.多见于肋间神经或三叉神经第一分支区，亦可见于腰腹部、四肢及耳部等。

3.神经痛是本病的特征之一。

四、诊断及鉴别诊断：

The pattern of the rash, in the form of blisters usually clinches the diagnosis, but a sample of the fluid from the blisters, or of blood can confirm it. It is unlikely that your doctor will need to do any tests.

带状疱疹根据群集小水疱，沿神经走向，单侧分布，有明显的神经痛，一般诊断不难。应与单纯疱疹、脓疱疮鉴别。

五、治疗：

原则：抗病毒、止痛、营养神经、预防感染。

补充：

带状疱疹后遗神经痛，PHN

举例简介

对比水痘

图片

结合病例

举例说明

（★－重点，☆－难点，)

了解常见的病毒性皮肤病的种类。Herpes zostter 是常见的疱疹型病毒性皮肤病之一。

★对比说明VZV可引起两种不同的疾病。取决于患者对VZV的不同免疫状态。强调Herpes zoster可获得终身免疫，几乎没有传染性。

★强调：VZV嗜神经和皮肤的特性是带状疱疹两大主要临床表现的原因。

联系中医称带状疱疹为缠腰火丹的病名强调好发部位。

★☆结合图片和病例形象具体地突出带状疱疹的特征。

★☆结合图片和病例形象具体地突出带状疱疹与单纯疱疹、脓疱疮的区别。

★  联系带状疱疹的发病机理、临床表现说明其治疗原则。

10分钟

基本内容

教学手段

课堂设计和时间安排

动物性皮肤病

疥  疮Scabies

是由疥螨寄生于人体表皮引起的一种接触性传染性皮肤病，可通过握手、同卧及性接触等密切接触传播，易在集体和家庭中流行。《医学金鉴》称“虫疥”。

Scabies is an infestation of the skin with the microscopic mite Sarcoptes scabei. Infestation is common, found worldwide, and affects people of all races and social classes.

Scabies spreads rapidly under crowded conditions where there is frequent skin-to-skin contact between people, such as in hospitals, institutions, child-care facilities, and nursing homes.

一、病因和传播途径：

How did I get scabies?

By direct, prolonged, skin-to-skin contact with a person already infested with scabies. Contact must be prolonged (a quick handshake or hug will usually not spread infestation). Infestation is easily spread to sexual partners and household members. Infestation may also occur by sharing clothing, towels, and bedding.

How long will mites live?

Once away from the human body, mites do not survive more than 48-72 hours. When living on a pewww.med126.com/job/rson, an adult female mite can live up to a month.

二、临床表现：

How soon after infestation will symptoms begin?

For a person who has never been infested with scabies, symptoms may take 4-6 weeks to begin. For a person who has had scabies, symptoms appear within several days. You do not become immune to an infestation.

1. 丘疹、水疱、隧道、结节。

• Pimple-like irritations, burrows or rash of the skin, especially the webbing between the fingers; the skin folds on the wrist, elbow, or knee; the penis, the breast, or shoulder blades.

2. 剧烈瘙痒

• Intense itching, especially at night and over most of the body.

Who is at risk for severe infestation?

People with weakened immune systems and the elderly are at risk for a more severe form of scabies, called Norwegian or crusted scabies.

三、诊断及鉴别诊断： 

How is scabies infestation diagnosed?

Diagnosis is most commonly made by looking at the burrows or rash. A skin scraping may be taken to look for mites, eggs, or mite fecal matter to confirm the diagnosis. If a skin scraping or biopsy is taken and returns negative, it is possible that you may still be infested. Typically, there are fewer than 10 mites on the entire body of an infested person; this makes it easy for an infestation to be missed.

根据接触传染史，好发部位，夜间剧痒等不难诊断。若找到疥螨即可确诊。

鉴别诊断：应与痒疹、皮肤瘙痒症、虱病、丘疹性荨麻疹、湿疹等鉴别。

四、预防和治疗：

1.隔离消毒。家庭内成员或集体生活者应同时治疗。

2.治疗以外用药为主，对瘙痒严重者可辅以镇静止痒药睡前内服。

2.并发化脓性感染时，应同时采用抗感染药物治疗。

Who should be treated for scabies?

Anyone who is diagnosed with scabies, as well as his or her sexual partners and persons who have close, prolonged contact to the infested person should also be treated. If your health care provider has instructed family members to be treated, everyone should receive treatment at the same time to prevent reinfestation.

How soon after treatment will I feel better?

Itching may continue for 2-3 weeks, and does not mean that you are still infested. Your health care provider my prescribe additional medication to relieve itching if it is severe. No new burrows or rashes should appear 24-48 hours after effective treatment.

小结：

解释说明

图片

结合病例

举例说明

解释说明

（★－重点，☆－难点，)

★结合疥螨生活史说明疥疮的传播和致病特点

★  结合图片说明疥疮的临床特点

★  强调疥疮的外用药治疗方法。

15分钟

5分钟

小

结

药疹亦称药物性皮炎，是药物通过内服、注射、吸入、灌肠、栓剂使用，甚至通过破损皮肤等途径进入人体后，在皮肤粘膜上引起的炎症性皮疹，严重者尚可累及机体的其他系统。临床上易引起药疹的药物有：①抗生素②解热镇痛类③镇静催眠药及抗癫痫药  ④异种血清制剂及疫苗等⑤中药。带状疱疹是常见的疱疹型病毒性皮肤病之一。以群集小水疱沿神经走向单侧分布，伴明显神经痛为特征。疥疮是由疥螨引起的接触性传染性皮肤病。

本次课所学医学单词：drug eruption ，medical dermatitis, Shingles , Herpes zostter，Scabies

复习思考题、

作 业

题

1、变态反应性药疹的特点？

2、药疹的临床表现类型及诊断要点？
3、重症药疹的治疗原则？
4、带状疱疹、疥疮的临床特点及治疗原则？

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