The 'Italy is just about to broke' story has come and gone all my life. In fact it makes an appearance roughly every 5 years.
We Brits wring like to wring our hands and feel terribly sorry for those Italians who we are certain are 'just about' to go broke. But the reality is a bit more complicated.
Italy might have a larger state debt that the UK, but its household debt is tiny. That makes Italy a lot less vulnerable to rising interest rates than the UK.
Italy has another advantage - it has a lot of very good industry that manages to export a lot. Italy is a bigger exporter than the UK It doesn't have our horrendous current account problems.
My guess is that Renzi will just manage to win this referendum to abolish the Senate, and the FTSE MIB will rise by about 20% over the next 6 months.
If he doesn't win, the fallout won't be too disastrous.