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.
Frequently, the diagnosis of rheumatoid arthritis is aided by tests that rule out other diseases. The most reliable and commonly used test to help diagnose RA is a blood test that looks for a specific antibody known as  rheumatoid factor..he most reliable and commonly used test to help diagnose RA is a blood test that looks for a specific antibody known as  rheumatoid factor..