If you don't know any languages other than English (e.g. German, Italian, French, etc), is it okay to cite the abstract (which is in English) of a foreign article without reading the full text (which is in the native language)? I appreciate if you provide a reference too (e.g. APA Manual, etc).
Ultimately, you and your co-authors are responsible for the contents of your manuscript. You can cite abstracts of works you haven't read in full, in any language, including your native tongue. However, misuse of such abstracts can always be called out by the reviewers of your paper. You will be responsible for defending your choices in the review process, if need be.
Ultimately, however, citing a foreign-language abstract ultimately is no different than citing one in English. The exact details depend on the citation format for the journal you intend to submit to, so check their guidelines. In general, you do not translate titles of articles or journals into their English language equivalent (unless the journals have done so themselves!).