Vanilla planifolia with spreading brown area

[Kethry1313]

I got this vanilla at the Philly Flower Show last month and it was going great, but I started noticing a brown spot on the vine and it started to spread. It started at one of the root nodes and now it's starting to effect one of the leaves. Does anyone one have a clue what this is?



Should I cut it off below the brown area? And if so, can I save the plant above the effected area since the plant above it seems to be very healthy.



Thanks for any help.