Cyclic vomiting and elevation of creatine kinase associated with bitemporal hypoperfusion and EEG abnormalities: a migraine equivalent?

A 13-year-old mentally retarded boy suffered from repeated vomiting attacks since infancy. Each episode lasted 2 to 10 days, and was precipitated by respiratory infection, exercise or stress. During an attack he became irritated, agitated and amnesic, but did not have headaches or seizures. Associated findings were transient elevation of serum creatine kinase (CK) (331-3381 IU/l), and of plasma ACTH and cortisol. The raised CK level was the result of muscle hypertonicity. Ictal EEGs showed delta activity in the front-temporal areas, and inter-ictal IMP-SPECT revealed hypoperfusion in both temporal regions. Unlike the periodic ACTH-ADH discharge syndrome, neither hypertension nor depression developed. These attacks were diagnosed as a migraine equivalent and were suppressed with phenytoin. From the EEG and SPECT findings, we concluded that the vomiting and behavioural changes were related to the paroxysmal vascular abnormality in the temporal regions, but it was not easy to make the distinction between migraine and focal epilepsy. Before a diagnosis of the periodic ACTH-ADH discharge syndrome is made, the possibility of migraine equivalent should be considered.