A two month baby presents with epiphora and regurgitation. The most likely diagnosis is:
Mucopurulent conjunctivitis
Buphthalmos
Congenital dacryocystitis
Encysted mucocele
Congenital dacyrocystitis is mainly due to membranous occlusion at the lower end near the valve of Hasner. Clinical features include Epiphora, positive regurgitation test and swelling of the sac. Ref: A.K KHURANA (2005), Chapter 15, "Disease of The Lacrimal Apparatus", In the book, "Opthalmology", 3rd Edition, Newdelhi, Page 342