A study came out earlier this year showing a connection between autoantibodies and pots. http://www.dysautonomiainternational.org/blog/wordpress/new-evidence-of-autoimmunity-in-pots/
At this point, this testing is not available outside of research. However, researchers hope that additional research will lead to new treatments for POTS. Other sources (including Richard Horowitz) have advocated testing for antiganglioside antibodies with POTS. Does anyone have any information or experience about having this done?