From the manga:

Original: Oreha Konoha no Aburame Ichizoku
Translated: I am from the Leaf's Aburame Clan/Household.

Shino never mentions that he is a chuunin, hence it was a mistranslation.

After looking closely at that particular chapter, it seems the translator used a Chinese scan. Some things may have been altered from the transition from Japanese to Chinese and from Chinese to English.