I have seen both. I tried to think about the count. When it comes to "nothing", it indicates a number of 0, which in English should be expressed by plural. However, both forms are common.
Which form should I use? Are(is) there any difference(s)?
A similar question is linked here: Should I use "What is the difference..." or "What are the differences..." if I don't know how many difference(s) there is/are?