In my book, The Readers Advisory Guide to Street Literature, I make the case that Street Lit is a sub-genre of Urban Literature. Urban Literature is a genre that features stories about city experiences (as opposed to rural experiences), regardless of ethnic identity or socio-economic status. In essence, urban literature are stories about city living (fiction and non-fiction).
Street Lit is a sub-genre of Urban Literature because the stories depict a certain flavor/aspect of city life and reality based on socio-economic status. Many people mistakenly think that Street Lit is an African American / Latino genre and it is not. In yesteryear in America, street lit stories were about European immigrants and their survival stories as low-income city dwellers. Today it’s about the current groups that live in those low income areas and those people just happen to be African American and Latino, for the most part, but by no means, exclusively.
Multicultural Literature doesn't directly factor into Street Lit or Urban Literature, in my humble opinion; unless we’re talking about the fact that the current outcome of Street Lit depicts a diverse group of city dwellers which would include everyone: European Americans, African Americans, Latin Americans, Asian Americans, and characters of varying sexual orientations, mobility levels, languages, and literacies.