1 Cold hands and Itching skin and Cold feet (10 causes). 2  Cold hands and Itching skin and Weakness (10 causes). 3  Cold hands and Itching skin and Breathing difficulties (9 causes). 4  Cold hands and Itching skin and Confusion (9 causes).
Rheumatoid factor (RF) Rheumatoid factor (RF) is a blood test that measures the amount of the RF antibody in the blood. Most of the time, 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.
A. A. A. Doctors often give people the rheumatoid factor blood test to help diagnose rheumatoid arthritis (RA). It measures rheumatoid factor, an immune system chemical thatâs in the blood of many, but not all, people with RA. Keep in mind that by itself, this test does not show whether you have RA.. A. Doctors often give people the rheumatoid factor blood test to help diagnose rheumatoid arthritis (RA). It measures rheumatoid factor, an immune system chemical thatâs in the blood of many, but not all, people with RA.