Two families manifested hereditary chronic biologic false-positive (BFP) seroreactions for syphilis. In one family, this trait was demonstrated in four of seven members, affecting three generations, grandfather, son, daughter, and granddaughter. Grandfather and son manifested increasing reagin titers over a period of 11 to 17 years. Positive Coombs' tests indicating autoantibodies were demonstrated in two seroreactors. In the second family, three of five members were affected, father, son, and daughter. The chronic BFP reaction appears to be a genetically transmissible trait associated with humoral autoantibodies with the potential for autoimmune disease.
Kostant GH. Familial Chronic Biologic False-Positive Seroreactions for SyphilisReport of Two Families, One With Three Generations Affected. JAMA. 1972;219(1):45–48. doi:10.1001/jama.1972.03190270023005