A review of the causes of central pontine myelinosis: yet another apoptotic illness?

One of the well recognized stimuli for central pontine myelinosis (CPM) is the rapid correction of chronic hyponatraemia. Conventionally this has been perceived to lead to pontine glial cell swelling through osmosis and event ually to cell death. However, although a purely osmotic argument has been c entral to any patho-physiological understanding of CPM, there are deficienc ies in this approach that do not account for why certain individuals develo p CPM with relatively mild osmotic insults. Here we review the varying aeti ologies of CPM and propose a novel hypothesis for CPM causation by suggesti ng that individuals predisposed to CPM have inadequate energy provision as well as other factors that result in a pro-apoptotic drive, which renders t hem susceptible to brain injury from diverse causes. In CPM, the precipitan t of brain injury appears to be osmotic stress. Furthermore, this model sug gests a number of therapeutic interventions that may prevent or at least mi tigate the consequences of CPM.