Background: To report the microbiological isolates, aetiology, complications, antibiotic susceptibilities, and clinical remission of dacryocystitis and canaliculitis in a prominent tertiary ophthalmic teaching and referral hospital located in northern China and to offer appropriate recommendations for preventing and formulating drug treatment strategies.

Methods: This prospective study recruited a total of 477 participants who had been diagnosed with either dacryocystitis or canaliculitis. The cohort comprised 307 patients with chronic dacryocystitis, 111 patients with acute dacryocystitis, and 59 patients with canaliculitis. Purulent discharge from the lacrimal duct was collected using a sterile swab and immediately subjected to microbial culture. Antimicrobial susceptibility testing was conducted following established protocols. All participants were scheduled for follow-up visits within 14 days after receiving antibiotic therapy.

Results: The present findings indicated that women exhibited a higher susceptibility to the condition, as evidenced by the occurrence of 367 cases in comparison to 110 cases among men. Among the 477 patients, definitive causes were established in 59 individuals, accounting for 12.4% of the patients. Additionally, ocular complications were reported by 132 patients, representing 27.7% of the total. Monocular involvement was observed in the majority of cases, with 402 out of 477 patients (84.3%) affected, while binocular involvement was present in 75 patients (15.7%). In total, 506 microbiological strains were recovered from 552 eyes, with Staphylococcus epidermidis (16.4%) being the most prevalent microorganism. Other predominant isolates included Corynebacterium macginleyi (9.1%), Staphylococcus aureus (5.1%), Streptococcus pneumoniae (4.9%), Haemophilus (4.4%), Propionibacterium acnes (3.5%), and Eikenella corrodens (3.1%). Among the 12 isolated fungi, Candida parapsilosis accounted for 66.7%. The susceptibility to antimicrobial agents tested in gram-negative bacilli (79.5%) was observed to be higher than that of anaerobic bacteria (76.7%) and gram-positive cocci (55.4%). With pharmacological therapy, the remission rate of acute dacryocystitis (72.7%) was found to be higher than that of canaliculitis (53.3%) and chronic dacryocystitis (42.3%).

Conclusions: This study highlights the microbial spectrum of dacryocystitis and canaliculitis, particularly C.macginleyi, E.corrodens and C.parapsilosis, which are also more frequently isolated. Vancomycin and imipenem may be more effective treatment options. Most cases have an unknown aetiology, and essential preventive measures involve postoperative cleansing of the lacrimal passage following eye and nasal surgeries, as well as the proactive management of rhinitis.