八、皮肤病

null（一）真菌性皮炎（癣）Dermatophytosis（Ringworm） （一）真菌性皮炎（癣）Dermatophytosis（Ringworm） 八、皮肤病null 皮肤真皮层的炎症，以丘疹、脱屑、瘙痒为特征。主要由狗小孢子菌、石膏样小孢子菌、须发癣菌感染引起。 接触性感染，人畜共患。null Dermatophytosis is caused by a fungus（真菌） not a worm（蠕虫）, and the lesion is not always in the shape of a ring. Since fungi are everywhere in our environment, it is difficult to determine which pets will develop the problem. The fungus that causes Ringworm can be cultured from the hair coats of normal dogs and cats. These pets might be carriers of the disease to other pets along with people. null患部断毛、掉毛或出现圆形脱毛区，皮屑较多。 也有的不脱毛、无皮屑而患部有丘疹、脓疱或脱毛区皮肤隆起、发红、结节化。症状：null须发癣感染时，患部多在鼻部，位置对称。 患病犬的面部、耳朵、四肢、趾爪和躯干等部位易被感染，病变处被毛脱落，呈圆形或椭圆形，有时呈不规则状。null慢性感染的犬猫病患处皮肤 表 关于同志近三年现实表现材料材料类招标技术评分表图表与交易pdf视力表打印pdf用图表说话 pdf 面伴有鳞屑或呈红斑状隆起，有的结痂，痂下因细菌继发感染而化脓。痂下的皮肤呈蜂巢状，有许多小的渗出孔。 null真菌性皮炎患犬的眼周围干性脱毛并逐渐向面部蔓延 null患犬的腰背部掉毛、脱屑 nullThis patch（斑点） is typical of the lesion seen in Ringworm. A diagnosis of this disease can not be made based just on the appearance of this lesion because other skin conditions can show similar nullWood’s灯检查： 在暗室里照射病患部位的毛、皮屑或皮肤缺损区，出现荧光为犬小孢子菌感染，而石膏样小孢子感染不易看到荧光，须发癣菌感染则无荧光出现。 诊断：null One of the simplest ways to diagnose Ringworm is with the Woods lamp, which is an ultraviolet（紫外线的） lamp, also know as a black light. 50% of the Microsporum（孢子） canis（犬属） species will fluoresce（发荧光） when the Woods lamp is placed near the area of hair loss. nullThe lamp emits a purple（紫色）/blue glow（蓝辉光） from the tube, and when there is fluorescence on the skin, it has a greenish（呈绿色的） appearance. Other material on the skin (dander（头皮屑）, medication, etc.) can also fluoresce, so interpretation is important null Since only 50% of a certain species of Ringworm fluoresces under the glow（辉光） of the Woods lamp, a culture is used to verify（检验、核实） the diagnosis: nullThe first step in the culture process is to gently remove hair follicles（小囊） in the area of the lesion null These hairs are cultured in a special media（媒体） that inhibits bacterial growth and enhances fungal growth. Since a fungus is a slow growing organism it can take up to several weeks to determine if there is growth or not. nullThe culture media prior to the start of the test Positive fungal growth after 10 days of incubation（孵化、培养） at room temperature null刮取患部鳞屑、断毛或痂皮置于载玻片上，加数滴10％KOH于载玻片样本上，微加热后盖上盖玻片。显微镜下见到真菌孢子即可确认真菌感染阳性。 null1.轻症、小面积感染可敷克霉唑、达克宁软膏或癣净等软膏，新药特比萘酚的临床疗效好。患部周围剪毛，洗去皮屑、痂皮等污物，用0.5%硫磺石灰液或0.5%洗必泰洗患部，再将软膏涂在患部皮肤上，2次/d，直到病愈。 治疗：null2.重症或慢性感染的病犬，应外敷软膏配合内服特比萘酚效果好；也可口服灰黄霉素，40~120mg/kgbw，拌油腻性食物(可促进药物吸收)，连用2周。怀孕犬忌服灰黄霉素，避免空腹给药，以防呕吐。 null3.患病犬应隔离。注意犬的用具、环境的消毒。 4.临床治愈后应继续用药2~4周，疗程一般1~3个月。 null（二）湿 疹 皮肤表皮和真皮的轻型过敏性炎症，发病原因较为复杂，一般认为先天或后天性过敏性素质和致敏因子的存在是发生本病因素。 null诊断要点 出现典型的多型性发疹症状，如红斑、丘疹、水疱、脓疱、湿烂和鳞屑。 有的病例呈现不典型症状，即出现某期的特征后而终止病程。 湿疹的局部伴发痒觉，动物啃咬、搔扒和摩擦发痒部。 慢性湿疹时，皮肤肥厚，弹力减退或消失，或形成皱壁而皲裂。 null拉布拉多犬急性湿疹的病蛮状况 null拉布拉多犬急性湿疹前肢腋下湿润期丘疹，可见小水泡 null松狮犬急性湿疹下腹部片状湿润丘疹 null6岁松狮犬湿疹结痂期null急性湿疹病变部苔癣样变化 null治疗 1.除去发病原因，给予易消化的饲料，补充维生素，禁喂霉败饲料。保护患部，防止局部感染。及时治疗湿疹的原发病。null2.对水疱、脓疱和湿烂患部，涂布3~5％龙胆紫、美蓝或2％硝酸银，或撒布滑石粉、氧化锌、次没食子酸铋等，或涂布水杨酸氧化锌软膏、氧化锌软膏。当炎症缓解之后，可涂布可的松软膏、地塞米松软膏或碘仿鞣酸软膏(1﹕5)。还可配合应用自体血液疗法、普鲁卡因疗法，并补充VB1。Allergic Dermatitis 过敏性皮炎 Allergic Dermatitis 过敏性皮炎 一、Introduction 1.Allergies are one of the most common causes of skin conditions. Allergies are encountered in pets, especially dogs, as often as we see them in humanoids. The main difference between us and pets is that allergies in pets tend to cause skin conditions. null2.Allergies can be hard to control and are chronic in nature. This causes significant frustration（挫折） for pet owners and discomfort for pets. A correct diagnosis along with proper therapy instituted（创立） early in the course of the disease will minimize this frustration. null二、Types There are 3 main types of allergies in relation to skin conditions. It is possible for a pet to have a combination of all 3 allergy types:null1. Food Allergy They are caused by an allergic reaction to ingredients or preservatives in food. It is estimated by some veterinary dermatologists（皮肤病学者） that food allergies account for only 10% of all the allergies that cause allergic dermatitis. In those pets that truly have food allergy, a high percentage also have atopy（遗传性过敏症） at the same time. Cats might have more food allergies than dogs. null2. Flea（跳蚤） Allergy Dermatitis (FAD) When a flea bites a dog or cat it is looking for a meal of blood in which to nourish itself. In order to suck this blood it inserts an anticoagulant（抗凝血剂） into its saliva（唾液） to prevent the blood from clotting（凝结） while it sucks it through its small proboscis（鼻子）. It is the allergens（过敏原） in this saliva that cause an allergic reaction to occur.null3. Atopy（遗传性过敏症） or Allergic Inhaled（吸入） Dermatitis Canine atopy is a genetically determined predisposition（易患病的体质） to produce IgE antibodies when exposed to an allergen. Re-exposure to this same allergen in the future causes allergic skin disease. It is estimated that between 3% and 15% of dogs have atopy.nullCommon allergens that cause this reaction are ragweed（豚草）, pollen（花粉）, house dust, animal dander（皮屑）, feathers（羽毛）, grasses, trees, and shrubs（灌木）. The allergens can be inhaled, pass through the pads（垫） of the feet, and even possibly ingested（摄取、咽下）. Since these compounds are in abundance（丰富、充裕） everywhere, it is apparent that preventing exposure in the first place is impossible.nullIf fleas are not a factor, atopy accounts for up to 90% of the allergies that cause allergic dermatitis. Only a small percent of these pets with atopy also have a food allergy at the same time.null三、Symptoms The most consistent（一致的） symptom in pets with allergic skin disease is excessive（过多的） itching（痒的）. The medical term for this is pruritis. High strung dogs might itch more than placid（平静的） dogs. Chewing（咀嚼）, biting（啃咬）, or licking（舔）, or rubbing（擦、磨） the skin can all be manifestations（显示） of pruritis.nullDogs can chew so incessantly（不间断地） that they wear down their incisors null In dogs some of the most common areas for pruritis to occur are the face, feet, and armpit（腋窝） areas. As the problem progresses the whole body might be involved. Some pets will scratch（搔抓、刮擦） excessively but not show any problems with their skin. nullThe slight redness (erythema红斑) to the face of this dog nullThe dark, stained（玷污的） areas on this poodle‘s（狮子狗） foot are due to excessive licking. The color change is due to the chronic saliva and the changes it causes on the haircoatnullThis dog's skin is oily from chronic rubbing nullThis Golden Retriever has significant redness (erythema) on its ear flaps null Cats get allergies also, although not as frequent as in dogs. They might exhibit the same or different symptoms. Different symptoms include tiny bumps（肿块） throughout the body, ulcers on the lips, excoriation（表皮脱落） of the neck, and even patches（斑点） of missing hair (alopecia（秃头症）) without any skin lesions. Ear problems related to allergies are rare in cats compared to dogs. Cats get a problem called psychogenic（精神性的） alopecia that can be similar in appearance to atopy.nullThis cat has an allergy（敏感症） that caused it to irritate the skin above its eye nullThis is a severe version of an ulcer on the lips. It is called the Eosinophilic（嗜酸细胞的） Granuloma（肉芽肿） Complex null四、Diagnosis Since the symptoms of allergic skin disease mimic（模仿） those of other skin diseases, a thorough approach is needed to differentiate them. In every disease we encounter we follow the tenets（原则） of the diagnostic approach to ensure that we make an accurate diagnosis, and that we do not overlook（没注意到）some of the diseases that are also encountered in conjunction with skin diseasesnull1. Signalment（特征性症状） Typically, atopy occurs in mature dogs between 1- 3 years of age, although it can occur earlier . The condition rarely starts in dogs over 6 years of age.nullMost dogs get their first exposure to an allergen and develop sensitization in their first exposure to a pollen（花粉） season. Symptoms usually occur during their second season of exposure to the pollen allergen when the immune system has its exaggerated（夸大的）response to the allergen and produces high levels of IgE. Dogs that are highly allergic can show signs of atopy during their first season of exposure to pollen allergens. It depends on how long the pollen season lasts and how rapidly their body produces the IgE antibodies. null2. History Atopy tends to be a progressive disease with worse symptoms each allergy season. Many dogs will be more affected during a specific season. As time goes on, dogs can have allergies year round. It is not a contagious（传染性的） disease, so other dogs, cats, and people in the same household do not usually have symptoms .nullThe progeny（后裔） of atopic dogs are more prone to developing atopy than other dogs. Careful breeding therefore can help minimize the occurrence of this problem. nullPets that have been treated with cortisone in the past, and did not improve, give us a clue that something else besides an allergic disease is involved. nullFood allergies in dogs and cats can start at any time in a pet‘s life, even those on the same diet for a long period of time. Non-seasonal allergies bring food allergies to mind, along with vomiting（呕吐） or diarrhea（腹泻）, although these are not consistent findings. The skin lesions in food allergy are indistinguishable from atopy, but have a propensity（倾向） to show only inflammation of the ears. Feeding dog and cat foods that contain ingredients that pets are routinely（usually） allergic to might also clue us in to a food allergy. nullFlea allergies are suspected whenever we are presented with a pet that has a skin condition and is not on routine（常规的） flea control. This is true even for pets that never go outside. Other pets in the household that are itching might also indicate fleas in the environment. Flea allergies routinely cause hair loss at the lower back area (called the dorsal-lumbar area), which is not typical of atopy and food allergy null3. Physical Exam The physical exam of a dog with a skin condition is the same as any other sick pet. We examine the whole body for clues as to the cause of the skin condition. The distribution of the skin lesions gives us a clue as to the cause, but is not consistent in all skin conditions. nullPyoderma（脓皮病）：This dog has licked so much it has maimed itself, and now has pyoderma, which is a skin infectionnullConjunctivitis：This is an inflammation of the eyes. The green discharge in the corner of the eye is from fluorescein（荧光素） stain （污点）that was checking for a scratch on the cornea nullLichenification （苔藓样硬化） and hyperpigmentation（色素沉着过多） nullChronic licking and scratching can cause thickening and dark pigmentation of the skin. The white arrow points to mild hair loss, hyperpigmentation, and lichenification in a Yorkie. nullAcute moist dermatitis （a hot spot） It is an area of skin that has been maimed（受伤的） from intense pruritis（瘙痒）. Pyoderma is also present, and the skin is very painful. Hot spots occur rapidly and can encompass（包围、环绕） a large section of skin in a short time. Affected areas usually include the rump（尾）and the side of the face. Other common causes include anal gland（肛腺） problems, ectoparasites and deep skin infections. nullThe serum that is exuded from the inflamed skin matts the hair and causes the problem to progress under the haircoat without realizing how serious it is nullHot spots can progress and cause serious skin conditions. This is painful and requires immediate care nullOtitis externa Sometimes an infection of the outer ear canal is the only symptom of allergy, especially food allergies. nullThis ear is so severely infected that it is difficult to ascertain the normal anatomy. The ear canal is completely occluded（使闭塞）, necessitating（迫使） surgery to correct it. nullPododermatitis：Infection of the feet can occur from chronic lickingnullLick granulomas（舔咬性肉芽肿）：There are many causes, allergies being a primary one. Other causes include arthritis, skin tumors, inflamed nerves, fungal infections, ectoparasites, and psychological factors like boredom and stress. Once the licking starts the problem is difficult to control. In some cases we have found that the use of the laser has been a significant help. nullThis small lick granuloma is on the front leg of a Golden Retriever nullFleas or flea dirt Flea dirt is literally droppings from the flea after is has bitten a pet and the blood has passed through the flea‘s digestive tract. It looks like pepper（胡椒粉）, and is easily visualized（显现） on a pet with a white haircoat.nullThis is an example of lots of flea dirt nullFlea eggs are small white particles, similar in size to flea dirt, that fleas lay in a pet's haircoat. They eventually drop off and contaminate the environment. A pet can have fleas and show no evidence of fleas, flea dirt, or flea eggs. Flea allergy dermatitis typically does not cause hair loss around the face, eyes, and ears like in atopy.null4. Diagnostic Tests Diagnostic tests are important even if we strongly suspect an allergy. In some situations other skin diseases can occur simultaneously（同时地） with the allergy. It is impossible to make a diagnosis in any skin condition just by looking at it. This is because there are many diseases that affect the skin, yet the skin has only a limited number of ways to exhibit signs of disease.nullSkin Scraping It is important to do a skin scraping in many cases of allergy because the lesions of atopy commonly mimic those of other diseases. Ectoparasites like demodex or scabies（疥疮） can cause skin lesions and itchingnullFungal Testscan Ringworm mimic allergy symptoms. Lesions from Ringworm tend not to be as pruritic（痒的） as allergies. Malassezia, another fungus, is commonly associated as a secondary problem when the skin is infected. Even though it is a normal part of an animals haircoat, it will add to the itching if other conditions are present. Common areas for Malassezia include the ears, lips, muzzle, between the toes, and the anal（肛门） area. Indications that Malassezia is present include pruritis, erythema, and greasy（油脂） skin with an offensive（讨厌的） odor. nullThyroid（甲状腺） Test Hypothyroidism（甲状腺机能减退） can cause skin conditions, although dogs with only hypothyroidism are not terribly pruritic.nullFecal（排泄物的） Exam Hypersensitivity（超敏性） to internal parasites can cause symptoms similar to atopy. This is not a common situationnullSkin Biopsy（活组织检查） In some cases it is difficult to make a diagnosis. When we are presented with this situation we will biopsy several small pieces of infected skin and have them analyzed by a veterinarian that specializes in tissue analysis of the skinnullAllergy Testing Allergy tests are performed in cases where we already have a diagnosis of allergy. The main purpose of allergy testing is to find exactly what your pet is allergic to, and also to set up a protocol（草案） for allergy injections. If giving allergy shots is not contemplated（预期的） then this test is of less value, although it will let us know what allergens we want to avoid. Trying to avoid these allergens though is almost impossiblenullIntradermal (skin) Test In this test, small amounts of materials that routinely cause allergies in dogs are injected under the skin. The reaction, if any, is graded, and a determination is made as to whether or not a pet is allergic to that specific allergen. null Your pet must be off of oral cortisone medication for at least 1 month before testing. If injectable cortisone is given, the waiting time is longer. Also, your pet must not be on any tranquilizers（镇定剂） at the time of testing and must be off of any antihistamine（抗组织胺的） medication for 10 days. null Pets usually are given a sedative（镇静剂） to calm them and to minimize the release of cortisone due to stress, which will affect the outcome. The hair on the side is clipped where there is no current dermatitis occurring. A tiny amount of histamine（组胺） is injected first. If there is no reaction to histamine, the full test is postponed. A small amount of sterile saline is also injected as a control. nullThe areas where the allergen is injected are marked null Numerous allergens are injected into the skin and a reaction is noted at 15 minutes and again at 30 minutes. The reaction we are looking for is called a wheal（水疱）. A positive test to a specific allergen occurs when the reaction is in between the saline and histamine tests in size. nullIn some cases the wheal is obvious, in others it is subtle, which is part of the interpretation process nullRAST (in vitro在生物体外的 test) RAST stands for radioallergosorbent（放射变应原吸附的） test. Another in vitro test is called the ELISA (enzyme linked immunosorbant assay) test. RAST tests for the levels of allergen specific IgE. null The RAST test has advantages over the intradermal test. There is no clipping, sedating, and there is no potential to have an adverse reaction（有害反应） to an allergen injected into the skin. There is less of a chance that prior drug therapy (cortisone) will influence the outcome. Also, it can be used in patients that have dermatitis. null The primary disadvantage is the fact that false positives are more common when compared to the intradermal test. null五、Treatment Treatment is aimed at all the factors that contribute to pruritis. For example, a pet that is normally not atopic might become so if exposed to fleas or if it gets a pyoderma. This concept is called summation（总和） of effects, and might push the pet over what is called the pruritic null1. Avoidance Obviously, if it is exposure to an allergen that causes the problem in the first place, then logic will dictate that we eliminate this exposure. In reality though, these allergens are everywhere. Minimizing exposure can be beneficial since it will decrease the allergen load, and hopefully keep your pet under the pruritic threshold（极限）.null2.Flea Control Since we live in a flea endemic area year round, we cannot emphasize the importance of proper flea control in any pet that has a skin condition. Even pets that are 100% indoors are possible flea victims.null The products available today are a significant improvement over flea control products in the recent past. They are economical, safe, effective, and very convenient. The two main products we recommend are Advantage© and Program©. null3.Anti-inflammatories Cortisone：When used judiciously（审慎地）, and under a doctor‘s supervision（监督）, it is one of the most important drugs we have. nullCortisone has been abused by some people, leading to a bad name for this drug in some people's minds. nullCortisone use is usually reserved for flare-ups（闪光，short time use of high doses）, since long term use has the potential for causing side effects. Long term use of high doses of cortisone can lead to hair loss, thinning of the skin, liver problems, stomach problems, and muscle weakness. The overuse of cortisone can also cause iatrogenic（医疗性的） Cushing's disease. null4.Antihistamines（抗组胺） Antihistamines can be effective in treatment in some cases. They counteract（阻碍） the release of histamine from the mast cell（肥大细胞）, which as you know is the source of the itching. They are the mainstay（支柱） of our long term medical treatment for skin allergies. Occasional side effects include drowsiness（睡意） and dry mouth, both of which tend to resolve. In general, they are safe to use on a long term basis.nullSome of the common antihistamines we use are: Benadryl（盐酸苯海拉明） Atarax（安泰乐，盐酸羟嗪） Tavist（富马酸氯马斯叮） Chlorphenaramine（氯苯吡胺，扑尔敏） Amitryptyline（阿米替林） null5.Antibiotics Some dogs scratch so severely they cause a secondary bacterial infection of the skin called pyoderma. This secondary bacterial infection intensifies（强化） the itching. These dogs need treatment with antibiotics for several weeks.nullthey need to be bathed with shampoo that will help（治疗） the skin infection. Long term use of antihistamines are not effective if a skin infection is allowed to persist. nullIf a hot spot is