so a similar question was asked recently and the answer given there works here:
Or, OP can look it up in a good dictionary, or better yet, an etymology dictionary. Here's The Online Etymology Dictionary's take on the word (see entry 2):
that same source says
"male Latin inhabitant of the United States" (fem. Latina), 1946, American English, from American Spanish, shortening of Latinoamericano "Latin-American" (see Latin America). As an adjective, attested from 1974.
so no, you can't call an italian latino because latino is an abbreviated form of latin american (and latin america is the former colonies of spain and portugal)