哮喘在孩子中是慢性疾病的领导因素。它在美国影响多达10%-12%的孩子，而且，原因不明，患儿比例逐渐增多。它能从任何年龄开始，但是大多数的孩子在五岁时有了他们的第一个症状。

　　什么使一个孩子变得更有可能发展成哮喘?

　　有许多危险因素导致孩童时期哮喘。这些包括:

过敏症的出现；
哮喘或过敏症的家庭历史；
经常发生呼吸器官的感染；
出生体重低；
出生前后的烟草接触；
是男性；
是黑人；
来自低收入家庭；

　　为什么患哮喘较多的是孩子?

　　没有人真的知道为什么越来越多的孩子正在得哮喘。一些专家建言，孩子是遭受了越来越多的过敏原，像是灰尘，空气污染和二手烟。这些因素全部是哮喘的诱因。其他怀疑，孩子没有通过患足够的孩童时期疾病以建立他们的免疫系统。看来，身体无法提供足够抗体的免疫系统的混乱，可能在引起哮喘方面担任一个角色。

　　而且“减少母乳哺育比率的建议”已经阻止免疫系统的重要物质被传给宝贝。

　　我如何能知道我的孩子是否有哮喘?找寻的特点和症状包括:

　　1、时常发生咳嗽，可能在游戏期间发生，在晚上，或者笑的时候。
　　2、知道“咳嗽可能是出现的唯一症状”是很重要的。
　　3、在游戏期间活力不足
　　4、迅速地呼吸
　　5、感觉胸部疼痛或不舒服
　　6、当吸入的时候，有吹口哨似的声音
　　7、在吃力或不自然的呼吸中能见到胸部运动(缩进)
　　8、呼吸困难，
　　9、勒紧了的脖子和胸肌肉
　　10、感觉疲劳或无力

　　要认识到不是所有的孩子都有相同的哮喘症状，而且这些症状能在相同的孩子中从哮喘插曲变化到下一段插曲。也要注意，不是全部喘息或者咳嗽由哮喘所引起。

　　以5岁以下的孩子中，发生类似哮喘症状的最共同因素是，上面提到的呼吸器官的滤过性毒菌的传染，比如感冒。

　　如果你的孩子有呼吸问题，立刻找医生进行诊断。

　　如何确诊孩子是否患有哮喘?
　　哮喘时常难以在婴儿中诊断。然而，在年龄稍大点的孩子中，疾病时常能被诊断出，基于你孩子的病史，症状和身体的测试。

　　病史和症状描述。你孩子的医生将会对你的呼吸问题的任何历史感兴趣，或者你的孩子可能已经有，连同哮喘的家庭历史，过敏症，皮肤情况例如湿疹、或其他的肺部疾病。很重要的是，你描述你孩子的症状--咳嗽，喘息，呼吸困难，胸部感觉疼痛或僵硬--详细地，包括何时以及这些症状如何时常发生的。

　　身体的考试。在身体检查期间，医生将会听你孩子的心和肺。

　　肺功能测试。许多孩子也将会有胸X光和肺的功能测试。也叫肺功能测试，这些测试在肺和它能被呼气多快中测量大量的空气。结果帮助医生判定，哮喘程度有多严重。通常，5岁以下的孩子不能够进行肺的功能测试。医生在作诊断方面更重要的是依据历史、症状和考试。

　　其他的测试也可能被用来帮助识别特殊的哮喘诱因。这些测试可能包括：过敏症皮肤测试、验血和X光决定是否鼻窦炎或者gastroesophageal逆流疾病(引起的一种gastrointestinal情况酸胃内容的逆流进入食道之内或者甚至进入肺之内)正在弄复杂哮喘。

(本文由http://www.21very.com翻译)英语原文:

Asthma in Children: Symptoms and Risk Factors
Asthma is the leading cause of chronic illness in children. It affects as many as 10%-12% of children in the U.S. and, for unknown reasons, is steadily increasing. It can begin at any age, but most children have their first symptoms by age 5.

What Makes a Child More Likely to Develop Asthma?
There are many risk factors for developing childhood asthma. These include:

Presence of allergies
Family history of asthma and/or allergies
Frequent respiratory infections
Low birth weight
Exposure to tobacco smoke before and/or after birth
Being male
Being black
Being raised in a low-income environment
Why Are More Children Getting Asthma?
No one really knows why more and more children are developing asthma. Some experts suggest that children are being exposed to more and more allergens such as dust, air pollution, and second-hand smoke. These factors all are triggers of asthma. Others suspect that children are not exposed to enough childhood illnesses to build up their immune system. It appears that a disorder of the immune system where the body fails to make enough protective antibodies may play a role in causing asthma.

And still others suggest that decreasing rates of breastfeeding have prevented important substances of the immune system from being passed on to babies.

How Can I Tell If My Child Has Asthma?
Signs and symptoms to look for include:

Frequent coughing spells, which may occur during play, at night, or while laughing. It is important to know that cough may be the only symptom present.
Less energy during play
Rapid breathing
Complaint of chest tightness or chest "hurting"
Whistling sound (wheezing) when breathing in or out
See-saw motions (retractions) in the chest from labored breathing
Shortness of breath, loss of breath
Tightened neck and chest muscles
Feelings of weakness or tiredness
Keep in mind that not all children have the same asthma symptoms, and these symptoms can vary from asthma episode to the next episode in the same child. Also note that not all wheezing or coughing is caused by asthma.

In kids under 5 years of age, the most common cause of asthma-like symptoms is upper respiratory viral infections such as the common cold.

If your child has problem breathing, take him or her to the doctor immediately for an evaluation.

How Is Asthma Diagnosed In Children?
Asthma is often difficult to diagnose in infants. However, in older children the disease can often be diagnosed based on your child's medical history, symptoms, and physical exam.

Medical history and symptom description. Your child's doctor will be interested in any history of breathing problems you or your child may have had, as well as a family history of asthma, allergies, a skin condition called eczema, or other lung disease. It is important that you describe your child's symptoms -- cough, wheezing, shortness of breath, chest pain or tightness -- in detail, including when and how often these symptoms have been occurring.
Physical exam. During the physical examination, the doctor will listen to your child's heart and lungs.
Tests. Many children will also have a chest X-ray and pulmonary function tests. Also called lung function tests, these tests measure the amount of air in the lungs and how fast it can be exhaled. The results help the doctor determine how severe the asthma is. Generally, children younger than 5 are unable to perform pulmonary function tests. Thus doctors rely heavily on history, symptoms and examination in making the diagnosis.
Other tests may also be ordered to help identify particular asthma triggers. These tests may include allergy skin testing, blood tests and X-rays to determine if sinus infections or gastroesophageal reflux disease (a gastrointestinal condition that causes reflux of acid stomach contents into the esophagus or even into the lungs) is complicating asthma.