An Autobiographical Case Series of Familial Post Ambulatory Swollen Hands (POTASH): Hand Swelling in a Man and His Sister While Participating in a Half Marathon.

Post ambulatory swollen hands (POTASH) is an acquired condition characterized by swelling of the hands, thumbs, and fingers following either walking, hiking, or running; no other body sites are swollen. The asymptomatic hand swelling begins in adulthood and recurs after adequate ambulation. A distinctive feature of POTASH that is often present is a positive fist sign demonstrated by the inability of the affected person to clench their fingers into the palm and form a fist. POTASH usually resolves spontaneously within a few hours after stopping ambulation; however, less frequently, it can persist for one or two days. The pathogenesis of POTASH has not been determined. In this case report, POTASH is described in an adult man and his sister. Neither the man's parents nor two of his other younger sisters had POTASH. However, the man's wife also develops POTASH with prolonged exercise; none of the three biological adult children of the man and his wife had POTASH. Therefore, based on these observations, the possibility that POTASH may have an autosomal recessive mode of inheritance and/or may be sporadic is suggested.