Arlt's line are usually seen in:
Ocular pemphigoid
Trachoma
Vernal keratoconjunctivitis
Pterygium
Cicatricial trachoma linear scars may be seen in the sulcus subtarsalis, these are called Arlt'slines. Since its caused by Chlamydia trachomatis the antibiotic of choice is azithromycin. Ref: A.K KHURANA (2005), Chapter 4, "Disease of The Conjunctiva", In the book, "Opthalmology", 3rd Edition, Newdelhi, Page 90