血涂片

定义

A blood smear is a blood test that gives information about the number and shape of blood cells. It is often done as part of or along with a complete blood count (CBC).

选择的名字

Peripheral smear; Complete blood count - peripheral; CBC - peripheral

如何执行测试

A 血液样本 是必要的.

血液样本被送到实验室. There, the lab technician looks at it under a microscope. Or, the blood may be examined by an automated machine.

涂片检查提供以下信息:

• 白细胞的数量和种类(微分，或每种细胞的百分比)
• The number and kinds of abnormally shaped blood cells
• A rough estimate of white blood cell and platelet counts

如何准备考试

不需要特别准备.

考试的感觉如何

When the needle is inserted to draw blood, some people feel moderate pain. 其他人只感到刺痛或刺痛. Afterward, there may be some throbbing or a slight bruise. 这很快就会消失.

为什么要进行测试

This test may be done as part of a general health exam to help diagnose many illnesses. Or, your health care provider may recommend this test if you have signs of:

• 任何已知或疑似的血液疾病
• 癌症
• 白血病

A blood smear may also be done to monitor the side effects of chemotherapy or to help diagnose an infection, 比如疟疾.

正常的结果

Red blood cells (RBCs) normally are the same size and color and are a lighter color in the center. 血液涂片如有下列情况即属正常:

• 细胞外观正常
• 正常白细胞分化

Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results.

异常结果意味着什么

不正常的 results mean the size, shape, color, or coating of the RBCs is not normal.

Some abnormalities may be graded on a 4-point scale:

• 1+表示有四分之一的细胞受到影响
• 2+表示一半的细胞受到影响
• 3+表示有四分之三的细胞受到影响
• 4+表示所有细胞都受到影响

靶细胞的存在可能是由于:

• 不正常的 血红蛋白, the protein in RBCs that carries oxygen (血红蛋白opathies)
• Deficiency of an enzyme called lecithin cholesterol acyltransferase
• 缺铁
• 肝脏疾病
• 脾切除

球形细胞的存在可能是由于:

• Low number of RBCs due to the body destroying them (免疫性溶血性贫血)
• Low number of RBCs due to some RBCs shaped like spheres (遗传性球形红细胞症)
• 红细胞分解增加

Presence of RBCs with an oval shape may be a sign of 遗传elliptocytosis or 遗传卵形红细胞症. These are conditions in which RBCs are abnormally shaped.

Presence of fragmented cells (also called schistocytes) may be due to:

• 人工心脏瓣膜
• Blood disorder that causes blood clots to form in small blood vessels around the body and leads to a low platelet count (血栓性血小板减少性紫癜)
• Disorder in which the proteins that control blood clotting become overactive (弥散性血管内凝血)
• Infection in the digestive system producing toxic substances that destroy RBCs, 造成肾脏损伤(溶血性尿毒症综合征)

Presence of a type of immature RBCs called normoblasts may be due to:

• 血液紊乱叫做 胎儿成红细胞增多病 影响胎儿或新生儿的
• 扩散到骨髓的癌症
• Disorder in which there is excessive breakdown of 血红蛋白 (地中海贫血)
• Disorder of the bone marrow in which the marrow is replaced by fibrous scar tissue (骨髓纤维化)
• 脾切除
• 红细胞严重衰竭(溶血)
• Tuberculosis that has spread from the lungs to other parts of the body through the blood (粟粒疹的肺结核)

The presence of cells called burr cells may indicate:

• 不正常的ly high level of nitrogen waste products in the blood (尿毒症)

The presence of cells called spur cells may indicate:

• Inability to fully absorb dietary fats through the intestines (无β脂蛋白血症)
• 严重肝病

泪滴状细胞的出现可能表明:

• Anemia caused by bone marrow not producing normal blood cells due to toxins or tumor cells (myelophthisic process)
• 骨髓中的癌症
• 骨髓纤维化
• 严重缺铁
• 重型地中海贫血

The presence of Howell-Jolly bodies (a type of granule inside the red blood cells) may indicate:

• Bone marrow does not produce enough healthy blood cells (myelodysplasia)
• 镰状细胞性贫血
• 脾脏已被切除

The presence of Heinz bodies (bits of altered 血红蛋白) may indicate:

• α地中海贫血
• 先天性溶血性贫血
• Disorder in which RBCs break down when the body is exposed to certain medicines or is stressed because of infection (G6PD缺乏症)
• 不稳定的血红蛋白

稍微不成熟的红细胞的存在可能表明:

• 贫血伴骨髓恢复
• 溶血性贫血
• 出血

The presence of basophilic stippling (a spotted appearance) may indicate:

• Disorder of the bone marrow in which the marrow is replaced by fibrous scar tissue (骨髓纤维化)
• 铅中毒

The presence of sickle cells may indicate sickle cell anemia.

风险

There is little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a 血液样本 from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

• 大出血
• 昏厥或感到头晕
• 多次穿刺定位静脉
• 血肿(皮肤下淤血)
• Infection (a slight risk any time the skin is broken)

参考文献

贝恩BJ. 外周血涂片. 参见:Goldman L, Schafer AI主编. Goldman-Cecil医学. 26日艾德. Philadelphia, PA: Elsevier; 2020:chap 148.

克利格曼RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM. 血液疾病. 在:克利格曼RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. 纳尔逊儿科学教材. 21艾德. Philadelphia, PA: Elsevier; 2020:chap 124.

Merguerian MD, Gallagher PG. Hereditary elliptocytosis, hereditary pyropoikilocytosis, and related disorders. 在:克利格曼RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. 纳尔逊儿科学教材. 21艾德. Philadelphia, PA: Elsevier; 2020:chap 486.

Natelson EA, Chughtai-Harvey I, Rabbi S. 血液学. 见:Rakel RE, Rakel DP，编. 家庭医学教材. 9日艾德. Philadelphia, PA: Elsevier; 2016:chap 39.

华纳EA，赫罗尔德AH. 解释实验室测试结果. 见:Rakel RE, Rakel DP，编. 家庭医学教材. 9日艾德. Philadelphia, PA: Elsevier; 2016:chap 14.