Rasmussen's encephalitis and central precocious puberty. Neuroendocrinological characterization of three cases.

PURPOSE: Rasmussen's encephalitis (RE) is a chronic neurological disorder characterized by inflammation of the cerebral cortex, mainly unilateral, that leads to drug-resistant epilepsy and progressive neurological impairment. Central Precocious Puberty (CPP) is uncommon, albeit increased in frequency in patients with neurological conditions and the physiopathological bases of these associations remains unclear in most cases. Epilepsy has been proposed to play a role, as well as the accumulation of substances produced as a result of metabolism or tissue degeneration in some neurodegenerative diseases. However, CPP has not been previously described in patients with RE.

METHODS

From a series of patients affected by RE followed-up at a referral center, an in-depth review of the characteristics of those who developed CCP was carried out.

RESULTS

Three cases were identified, representing a relative frequency of 21.4 % for CPP. They were girls, of Caucasian ethnicity, without family history of CPP or any image-identified abnormalities in the hypothalamic area. In two cases CPP manifested immediately before the onset of the epilepsy (prior to the diagnosis of RE) and in the other, after epilepsy onset but coinciding with a worsening of the seizures. A GnRH test with pubertal response confirmed CPP in the three cases.

CONCLUSION

The high proportion of CPP in patients affected by RE suggested a plausible relationship between these two entities. Various factors involved, including neuroinflammation, are hypothesized in the present study. However, further studies are needed to elucidate the pathophysiological bases, which could provide insight in the understanding of both entities.