Contributor: Gordon K. Klintworth
Acute dacryocystitis is commonly due to an infection especially in association with an obstruction of the nasolacrimal duct. The responsible organism can be identified by examining the purulent drainage expressed or aspirated from the lacrimal sac. The material  should be swabbed directly onto culture media (blood agar and chocolate agar, thioglycolate broth) and smears of the material on glass slides should be evalauted after being stained with the Gram stain.

 It is characterized by exquisite pain, redness, tearing, discharge, and tender swelling over the lacrimal sac region below the upper border of the medial canthal tendon. Virulent strains of bacteria and host resistance factors in acute dacryocystitis can lead to complications of facial cellulitis, lacrimal sac abscess with skin fistulization, and rarely orbital cellulitis. Acute painful swelling of a noninflamed lacrimal sac can occur in the syndrome of acute noninfectious dacryocystic retention. In this condition a dacryolith lodges in a dependent position and acutely blocks nasolacrimal duct outflow.