Rheumatoid Remission in Pregnancy Linked to Fetal DNA
Rapid postpartum clearing associated with recurrence
THURSDAY, June 29 (HealthDay News) -- Rising levels of fetal DNA in maternal serum may be responsible for the disease improvements known to occur during pregnancy among women with inflammatory arthritis, according to new research in the July issue of Arthritis & Rheumatism.
J. Lee Nelson, M.D., of the Fred Hutchinson Cancer Research Center in Seattle, and colleagues conducted a prospective study of 25 patients, including 17 with adult-onset rheumatoid arthritis and six with juvenile idiopathic arthritis.
Seventy-nine percent of rheumatoid arthritis patients and all juvenile idiopathic arthritis patients experienced a remission or improvement of symptoms during pregnancy. The improvements corresponded with increases in serum fetal DNA. As fetal DNA quantities doubled, the likelihood of arthritis improvements increased 1.2-fold. Levels of serum fetal DNA were much lower among the four women who did not improve.
Recurrence of disease symptoms occurred in 90 percent of patients three or four months postpartum, coinciding with a drop in serum fetal DNA to very low or undetectable levels. "Whether the dynamic changes in fetal DNA reflect the potential for immune modulation or maternal arthritis, are a result of disease activity changes or are not causally related cannot be determined from these studies," the researchers conclude.