[Childhood periodic syndromes]

[Cyclic vomiting syndrome in children]

Cyclic vomiting syndrome (CVS) is a misrecognized and probably underdiagnosed disease that can affect up to 1.9% of the pediatric population and can occupy 15% of these children's time. It is characterized by acute attacks of vomiting, occurring with such a strict frequency that some parents can predict the date of their child's next attack. The pathophysiology of CVS is unclear, although the literature recognizes a common origin with migraine headaches, which has the same acute and prophylactic treatment. CVS is now included in the larger group of diseases called "episodic symptoms related to migraine" previously known as "childhood periodic syndromes." To distinguish between real CVS and other differential diagnoses can challenge the clinician. Additional investigations must be considered in accordance with the clinical presentation. Appropriate management of CVS should lead to an improvement in quality of life and school attendance.

Sex and the migraine brain

The brain responds differently to environmental and internal signals that relate to the stage of development of neural systems. While genetic and epigenetic factors contribute to a premorbid state, hormonal fluctuations in women may alter the set point of migraine. The cyclic surges of gonadal hormones may directly alter neuronal, glial and astrocyte function throughout the brain. Estrogen is mainly excitatory and progesterone inhibitory on brain neuronal systems. These changes contribute to the allostatic load of the migraine condition that most notably starts at puberty in girls.