Rheumatoid factor (RF) is part of the immune systemâs overactive response. It shows up in the blood of about 70% to 80% of people with RA. High levels of it are linked to more severe cases.Drawbacks: It misses 20% to 30% of cases of RA. It also shows up in other conditions, including: 1  Chronic hepatitis.ou could have these antibodies years before you get RA symptoms. This test can also predict cases of RA that could become severe. Drawbacks: It misses 10% to 15% of cases of RA.
Orange is a city located in Orange County, California. It is approximately 3 miles (4.8 kilometers) north of the county seat, Santa Ana. Orange is unusual in this region because many of the homes in its Old Town District were built prior to 1920.
Orange Beach, Alabama. Orange Beach is a city in Baldwin County, Alabama, United States. As of the 2010 Census, the population was 5,441.