血浆氨基酸

定义

血浆氨基酸 is a screening test, usually done on infants that looks at the amounts of 氨基酸 在血液里. Amino acids are the building blocks for proteins in the body.

选择的名字

Amino acids blood test

How the Test is Performed

大多数时候, blood is drawn from a vein located on the inside of the elbow or the back of the hand.

In infants or young children, a sharp tool called a lancet may be used to puncture the skin.

• The blood collects in a small glass tube called a pipette, or onto a slide or test strip.
• A bandage is put over the spot to stop any bleeding.

The blood sample is sent to a lab. There are several types of methods used to determine the individual amino acid levels 在血液里.

How to Prepare for the Test

The person having the test may be asked not to eat 3 or more hours before the test. Check with your child's health care provider for specific advice.

考试的感觉如何

There might be slight pain or a sting when the needle is inserted. You may also feel some throbbing at the site after the blood is drawn. The needle stick will probably cause an infant or child to cry.

Why the Test is Performed

This test is done to measure the level of 氨基酸 在血液里.

An increased level of a particular amino acid shows that there is a problem with the body's ability to break down (metabolize) that amino acid.

The test may also be used to look for decreased levels of 氨基酸 在血液里.

Increased or decreased levels of 氨基酸 在血液里 may occur with fevers, 营养不足, and certain medical conditions.

正常的结果

All measurements are in micromoles per liter (µmol/L). Normal values may vary between different laboratories. Talk to your health care provider about your specific test results.

丙氨酸:

• 儿童:200至450人
• 成人:230至510

Alpha-aminoadipic acid:

• Children: not detected
• 成人:未检测到

Alpha-amino-N-butyric acid:

• 儿童:8至37岁
• 成人:15至41岁

精氨酸:

• 儿童:44岁至120岁
• 成人:13至64岁

天冬酰胺:

• 儿童:15至40岁
• 成人:45至130岁

天冬氨酸:

• 儿童:0至26岁
• 成人:0 - 6岁

Beta-alanine:

• 儿童:0 ~ 49岁
• 成人:0至29岁

Beta-amino-isobutyric acid:

• Children: not detected
• 成人:未检测到

肌肽:

• Children: not detected
• 成人:未检测到

瓜氨酸:

• 儿童:16至32岁
• 成人:16至55岁

胱氨酸:

• 儿童:19至47岁
• 成人:30至65岁

谷氨酸:

• 儿童:32至140岁
• 成人:18岁至98岁

谷氨酰胺:

• 儿童:420 - 730
• 成人:390至650

甘氨酸:

• 儿童:110至240
• 成人:170 - 330

组氨酸:

• 儿童:68至120岁
• 成人:26至120岁

羟脯氨酸:

• 儿童:0 - 5岁
• 成人:未检测到

异亮氨酸:

• 儿童:37岁至140岁
• 成人:42岁至100岁 

亮氨酸:

• 儿童:70 - 170
• 成人:66至170岁

赖氨酸:

• 儿童:120至290
• 成人:150 - 220

蛋氨酸:

• 儿童:13至30岁
• 成人:16至30岁

1-methylhistidine:

• Children: not detected
• 成人:未检测到

3-methylhistidine:

• 儿童:0至52岁
• 成人:0至64岁

鸟氨酸:

• 儿童:44岁至90岁
• 成人:27至80岁 

苯丙氨酸:

• 儿童:26岁至86岁
• 成人:41至68岁

磷酸丝氨酸:

• 儿童:0至12岁
• 成人:0至12岁

Phosphoethanolamine:

• 儿童:0至12岁
• 成人:0至55岁

脯氨酸:

• 儿童:130 - 290
• 成人:110至360

丝氨酸:

• 儿童:93至150岁
• 成人:56岁至140岁 

牛磺酸:

• 儿童:11岁至120岁
• 成人:45至130岁

苏氨酸:

• 儿童:67岁至150岁
• 成人:92岁至240岁

酪氨酸:

• 儿童:26岁至110岁
• 成人:45 - 74岁

缬氨酸:

• 儿童:160 - 350
• 成人:150至310

The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.

What Abnormal Results Mean

An increase in the total level of 氨基酸 在血液里 may be due to:

• 惊厥
• Inborn error of metabolism
• 果糖不宽容
• Ketoacidosis (from diabetes)
• 肾功能衰竭
• 瑞氏综合征
• 实验室错误

A decrease in the total level of 氨基酸 在血液里 may be due to:

• Adrenal cortical hyperfunction
• 发热
• Hartnup疾病
• Inborn error of metabolism
• 亨廷顿舞蹈病
• 营养不良
• 肾病综合症
• Phlebotomus发烧
• 类风湿性关节炎
• 实验室错误

High or low amounts of individual plasma 氨基酸 must be considered with other information. Abnormal results may be due to diet, hereditary problems, or effects of a medicine.

注意事项

Screening infants for increased levels of 氨基酸 can help detect problems with metabolism. Early treatment for these conditions may prevent complications in the future.

参考文献

Dietzen DJ, Vieira Willrich MA. Amino acids, peptides, and proteins. In: Rifai N, Chiu RWK, Young I, Burnham C-A D, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7日艾德. St Louis, MO: Elsevier; 2023:chap 31.

克利格曼RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM. Defects in metabolism of 氨基酸. 在:克利格曼RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21艾德. Philadelphia, PA: Elsevier; 2020:chap 103.

莱利RS，麦克弗森RA. Basic examination of urine. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24日艾德. Elsevier; 2022:chap 29.