Multiple instances of the same (foreign) word

Question

Consider the following snippet:

The Spanish word lágrima comes from Latin lacrima which also has a descendant in English. When you cry, your eyes get their tears from special glands known as lacrimal sac. These glands are named after lacrima. Lacrima also happens to have descendants in other Romance languages.

If you notice, there are three instances of the Latin word in the snippet. If I am following a style where I italicize foreign language words, is it necessary for me to maintain consistency by italicizing every single occurrence of the same word just because it's foreign? Or should I just italicize the first instance of lacrima here?

Answer 1

If you want a certain style guides opinion, then you italicize just the first occurrence:

"7.49 Italics for unfamiliar foreign words and phrases

Italics are used for isolated words and phrases in a foreign language if they are likely to be unfamiliar to readers... If a foreign word becomes familiar through repeated use throughout a work, it need be italicized only on its first occurrence. If it appears only rarely, however, italics may be retained.

--Chicago Manual of Style Online, 16th editon

Answer 2

Italicize in all instances.

For example see mise en abyme here.

...Also "unheimlich" here.

EDIT: I want to hedge my original response by pointing out that both the MLA and Chicago style guides seem to disagree with me. Both argue that only the first instance should be italicized, unless there is a very long space of text between them. It's not clear that authors follow this rule, however.