类风湿性因子(RF)

定义

类风湿性因子(RF) is a blood test that measures the amount of the RF 抗体 在血液里.

如何执行测试

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.

How to Prepare for the Test

You do not need to take special steps before this test.

考试的感觉如何

You may feel slight pain or a sting when the needle is inserted. You may also feel some throbbing at the site after the blood is drawn.

为什么要进行测试

This test is most often used to help diagnose 类风湿性关节炎 or 干燥综合症.

正常的结果

Results are usually reported in one of two ways:

• Value, normal less than 15 IU/mL
• Titer, normal less than 1:80 (1 to 80)

If the result is above the normal level, it is positive. A low number (negative result) most often means you do not have 类风湿性关节炎 or 干燥综合症. However, some people who do have these conditions still have a negative or low RF.

Normal value ranges may vary slightly among different laboratories. Talk to your health care provider about the meaning of your specific test results.

异常结果意味着什么

An abnormal result means the test is positive, which means a higher level of RF has been detected in your blood.

• Many people with 类风湿性关节炎 or 干燥综合症 have positive RF tests.
• The higher the level, the more likely one of these conditions is present. There are also other tests that can be done to help make the diagnosis.
• Not everyone with a higher level of RF has 类风湿性关节炎 or 干燥综合症.

Your provider should also do another blood test (anti-cyclic citrullinated peptide 抗体 or anti-CCP 抗体), to help diagnose 类风湿性关节炎 (RA). Anti-CCP 抗体 is more specific for RA than RF. A positive test for CCP 抗体 means RA is probably the correct diagnosis.

People with the following diseases may also have higher levels of RF:

• 丙型肝炎
• Systemic lupus erythematosus
• 皮肌炎 和多肌炎
• 结节病
• 球蛋白血症引起混合
• Mixed connective tissue disease

Higher-than-normal levels of RF may be seen in people with other medical problems. However, these higher RF levels cannot be used to diagnose these other conditions:

• 艾滋病, 肝炎, 流感, 传染性单核细胞增多, and other viral infections
• 某些肾脏疾病
• 心内膜炎, tuberculosis, and other bacterial infections
• 寄生虫感染
• 白血病, 多发性骨髓瘤和其他癌症
• 慢性肺病
• 慢性肝病

在某些情况下, people who are healthy and have no other medical problem will have a higher-than-normal RF level.

参考文献

Aletaha D, Neogi T, Silman AJ, et al. 2010 Rheumatoid arthritis classification criteria: an American College of 风湿病学/European League Against Rheumatism collaborative initiative. Ann Rheum Dis. 2010;69(9):1580-1588. PMID: 20699241 pubmed.ncbi.nlm.国家卫生研究院.gov / 20699241 /.

Darrah E, Rosen A, Andrade F. Autoantibodies in 类风湿性关节炎. In: Firestein GS, Budd RC, Gabriel SE, Koretzky GA, McInnes IB, O'Dell JR, eds. Firestein & Kelley's Textbook of 风湿病学. 11日艾德. Philadelphia, PA: Elsevier; 2021:chap 59.

Sieghart D, Trouw L, Steiner G. Autoantibodies in 类风湿性关节炎. In: Hochberg MC, Gravallese EM, Smolen JS, van der Heijde D, Weinblatt ME, Weisman MH, eds. 风湿病学. 8日艾德. Philadelphia, PA: Elsevier; 2023:chap 96.

梅森JC. Rheumatic diseases and the cardiovascular system. In: Libby P, Bonow RO, Mann DL, Tomaselli GF, Bhatt DL, Solomon SD, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 12日艾德. Philadelphia, PA: Elsevier; 2022:chap 97.

Pisetsky DS. Laboratory testing in the rheumatic diseases. In: Goldman L, Schafer AI, eds. Goldman-Cecil医学. 26日艾德. Philadelphia, PA: Elsevier; 2020:chap 242.