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.
Testing for rheumatoid factor is like any other blood test. The rheumatoid factor test is done by drawing blood and analyzing it for the presence of this particular protein antibody. If the results show a certain level of rheumatoid factor, then the test reads positive for rheumatoid factor.