IGHE and cerebral creatine deficiency syndrome: Sera from seven ragweed allergic patients positive to CCDs and three individuals sensitized to CCDs but not to ragweed (PC1‐3) were pre‐incubated with nAmb a 1.01, rAmb a 1.03 and two CCD markers and tested for IgE reactivity to nitrocellulose‐blotted ragweed pollen extracts.