PLAID syndrome is an inherited condition characterised by antibody deficiency and immune dysregulation, first described in 2012.

It is characterised by cold-induced urticaria, autoimmunity, atopy and humoral immune deficiency.

[1] This condition is characterised by cold induced urticaria, autoimmunity, atopy and humoral immune deficiency.

It is however known that phospholipase C gamma is an important signalling mediation for natural killer cells.

[citation needed] Familial cold urticaria[8] This is considered a rare condition, with 30 patients described in the literature up to 2019.