关于冷诱导荨麻疹的5个问题

自从她是一个年轻的女孩，夏洛特莱佛士已经喜欢游泳。但是当她三年前在23岁时发育冷致慢性荨麻疹时，游泳池突然走出了界限。“我之前的几次荨麻疹，但他们一直在几天内消失了，”莱文说。“这次，他们来了几个星期。”

她当时不知道它，但她的荨麻疹，红色和肿胀的皮肤 - 被游泳在冷水中触发。冷诱导的荨麻疹（也称为冷荨麻疹）是一种慢性条件，这意味着没有治愈。大多数人在皮肤暴露在冷物体上时，大多数人都会经历反复发作，如冷水或冰，或者只是在寒冷的环境中，冻结户外气候或真正寒冷的室内空调。“与皮肤接触的寒冷温度导致身体内部的组胺释放，这导致荨麻疹，”Tanya Nino，M.D.，奥兰古郡，加利福尼亚州的圣约瑟夫医院的皮肤科医生。

直到她再次游泳，并与她的医生一起拍摄 - 夏洛特最终被诊断出患有冷荨麻疹。“我从来没有听说过它，”她承认。

不太令人惊讶，考虑到这是一个极其罕见的病情。根据审查，患有冷荨麻疹的确切人数未知，但发病率是占总人口的0.05％过敏与临床免疫学杂志。To give that figure some context, regular hives (known as plain old urticaria) affects about 20% of people at some point in their lives, according to the American College of Allergy, Asthma and Immunology.

So how do you know, exactly, if you have symptoms of cold urticaria or just run-of-the-mill hives? And, more important,why你得到它们，你如何防止和/或治疗你的下一次攻击？

冷诱导荨麻疹的类型是什么？

According to the National Organization for Rare Disorders (NORD), there are two types of cold-triggered hives. They are:

• Essential(acquired)
• 家族（遗传）

基本类型,症状成为明显的我mmediately after exposure to an external cold trigger, and they tend to last for only a couple of hours. “Usually, people with cold-induced chronic hives will notice raised welts after even just a few minutes of touching frigid air, liquid, or items.” says Milna Rufin, M.D. in internal medicine at NYU Langone Health in New York City.

伴有家族性肝癌荨麻疹，症状最多需要48小时。但是，当他们这样做时，你的荨麻疹通常会留下更长时间的日子。

这种情况有什么症状？

如果你有任何类型的冷荨麻疹，你可能会觉得瘙痒和红色皮肤，然后是灼热的感觉和荨麻疹的外观。被告知她有基本类型的冷荨麻疹的夏洛特说，她看起来蓬松和养，是粉红色的粉红色。

“Hives can take multiple shapes and sizes,” Dr. Rufin says. “Cold-induced hives usually appear within a few minutes of cold exposure and can sometimes wax and wane. The amount of time they are present can really vary, and can last hours to days.”

Cold-induced hives are typically found only on the parts of the body that are exposed to the external cold trigger—so they might appear on your hand if you touch ice, or on your face if you’re out in very cold weather. “Sometimes, if people have extended cold exposure, like when swimming in icy waters, you can see hives develop all over,” adds Dr. Rufin.

According to the Genetic and Rare Diseases Information Center (GARD), such reactions normally first occur in early adulthood, although the condition can present at any age, and is more common in females than males.

不太常见的症状收购或家族性寒冷urticaria include shortness of breath, wheezing, abdominal pain, rapid heartbeat (palpitations), low blood pressure, or even anaphylactic shock. The severity of the symptoms depends on the amount of exposure. “Swimming in a cold lake is more likely to trigger an anaphylactic response than holding an ice cube,” Dr. Nino says. If you feel your mouth, lips, tongue, or throat swelling, or are having trouble breathing, seek emergency medical care right away. NORD also lists fever, headache, anxiety, tiredness, and fainting as possible symptoms of cold urticaria.

So, What Causes Cold-Induced Hives?

There’s no single cause of essential cold-induced hives. However, the familial form of the condition can occur when an abnormal gene (known as CIAS1/NLRP3) is present. Such a mutation triggers increased activity of a protein complex known as the inflammasome, whose job is to regulate inflammation in the body. Basically, an uptick in inflammasome activity causes an increased release of a protein called interleukin (IL) 1B, which then lead to symptoms of inflammation.

According to NORD, this abnormal gene can be inherited from either parent, or can be the result of a new gene mutation caused by an environmental factor, such as exposure to ultraviolet radiation. The risk of passing this abnormal gene is 50% for each pregnancy, and the risk of getting it is the same for males and females.

在某些人中，患有影响免疫系统的潜在健康问题的潜在健康的担忧，如病毒感染或癌症的潜在健康问题引发了冷荨麻疹。这与身体的免疫反应和炎症细胞相关 - 基本上，免疫系统已经在过度使用过度，追求“威胁”，以真正威胁，如冷水。“所有免疫细胞一起互相募集并募集，包括释放组胺的肥大细胞，”Nino博士解释说。

如果您的医生怀疑您的冷荨麻疹是由潜在的健康问题引发的，它们可能会进行额外的测试，包括检查抗体对特定病毒感染的抗体，或癌细胞，蛋白质或由癌症产生的其他物质。

How, Then, Are They Diagnosed?

要确定冷是否触发荨麻疹，您的医生可能会在发布的指南中表现出一种叫冷刺激测试的内容Allergy2018年。这涉及放置一个冷的物体，就像冰块或冰袋一样，避开你的皮肤几分钟。（不是每个人都获得这个测试。“我的医生说，我的症状是清楚的，我患有冷荨麻疹，”夏洛特说。）

如果您有冷荨麻疹，红色肿胀的皮疹会在您的皮肤上开发，在删除物体后10分钟内与寒冷物体接触。Nord详细说明了这里的实际情况：在这种情况下需要暴露于冷的情况下，蜂巢实际上在皮肤上形成，因为您的身体的温度升起 - 在冷物体被带走后。

Can Cold-Induced Hives Be Cured?

因为冷荨麻疹是一种慢性病，所以没有治愈。如果你很幸运，可能会在几个星期或几个月后自己离开。否则，一系列治疗和预防性步骤可能有所帮助。不出所料，避免寒冷的温度和可能导致体温快速下降的任何东西是最重要的采取措施之一。

“We generally recommend that people with cold-induced urticaria should avoid the cold, but for some people, that may be totally impractical,” says Dr. Rufin before adding: “If you are in the hospital, it’s very helpful to tell your doctors that you have cold-induced chronic hives, so that your providers can warm any medications or treatments before it touches your skin.”

Over-the-counter antihistamines, like Clarinex (desloratadine), Claritin (loratadine), and Zyrtec (cetirizine) can help in mild cases of cold urticaria, Dr. Rufin says. In more serious cases, a prescription med might be needed. Xolair (omalizumab), which is normally prescribed to treat asthma, has been used successfully to treat people with cold urticaria who didn't respond to other medications. And if you’ve had a severe systemic reaction to the cold—such as anaphylactic shock—Dr. Nino and Dr. Rufin recommend talking to your doctor about carrying an epinephrine pen with you, especially during the winter if you live in a cold climate.

Charlotte is proof that if you make certain changes—and follow your doctor’s advice—you don’t have to let cold urticaria control your whole life, or prevent you from doing your favorite cool activities. “Cold-water swimming is out, but I get my swim fix in a heated indoor pool,” she says. “I take an antihistamine before I get in the water, which reduces the redness and swelling. And if we’re having a cold weather spell, I stay home—and warm—as much as possible.”