Older patients are predisposed to the condition as the lacrimal drainage system loses its elasticity and thins, and tears fail to flush debris through the complex. Patients with poor hygiene are at greater risk. The primary etiology of dacryocystitis is nasolacrimal obstruction secondary to mucocele of the lacrimal sac, which is precipitated by chronic blockage of the interosseous or intermembranous nasolacrimal duct. Most cases of nasolacrimal duct obstruction are found in the older population, and result from chronic mucosal degeneration, ductile stenosis, stagnation of tears, and bacterial overgrowth.
Infantile dacryocystitis is uncommon but presents with the same signs and symptoms.
Lacrimal sac obstructions often produce signs and symptoms similar to dacryocystitis but not as severe. They are collectively known as canaliculitis. These infections are differentiated by solid concretions called dacryoliths, which can be expressed from the infected lacrimal sac. Dacryoliths can result from bacterial, fungal or viral infections. Manage febrile patients with extreme caution.