You certainly won't want to add a language specific version of each field into the same table. That would mean changing the table structure for each new language.
I'd suggest adding a description_id field rather than description to table items, which would link to another table containing the description_id, actual description and also a language_id. Then finally a 3rd table containing language_id and language.
table: items
item_id
item_parent_id
item_name
description_id // foreign key to descriptions
table: descriptions
description_id
description // This would be the description repeated in each language
language_id // foreign key to languages
table: languages
language_id
language // english, german, french and so forth
You'd select which language you want to use by selecting from the language table (maybe stick the id in a session), then query for the fields using the language_id as the anchor point.
