Introduction: The aim of the study is to determine microbiological spectrum of acute and chronic dacrocystitis and their antibiotic susceptibility pattern in a tertiary care teaching hospital.

Materials and methods: This prospective observational study was carried out in the department of microbiology and ophthalmology of a tertiary care teaching hospital. 205 were patients diagnosed with dacrocystitis and catagorised into acute and chronic dacrocystitis. Specimens for microbiological analysis were collected under strict aseptic precautions from dacrocystitis. All  specimens were subjected to standard microbiological procedures. methicillin resistant Staphylococcus aureus( MRSA) and extended spectrum of beta lactamases(ESBL) strains were also detected as per CLSI guidelines.

Results: A total of 205 specimens were collected from cases of dacrocystitis. 55(26.83%) specimens were from acute dacrocystitis and 150 (73.17%) specimens were from chronic dacrocystitis. Culture positivity was high in the specimens collected from chronic dacrocystitis(110/150;73.33%). Overall Staphylococcus.aureus was the predominant pathogen  found in both acute 9(29.03%) and chronic dacrocystitis 27(24.55%). Among Gram negative bacilli, H. influenza 4(12.90%) was found to be the  predominant pathogen in specimens collected from acute dacrocystitis and preponderance Pseudomonas aeruginosa9(8.19%) was revealed in specimens collected from chronic dacrocystitis.  33.33% were found to be methicillin resistant Staphylococcus aureus(MRSA) in acute dacrocystitis. In chronic dacrocystitis 40.74% strains of S.aureus were found to be MRSA.  Out of 8 Gram negative bacilli, E.coli(25%) was found to be ESBL producers from cases of acute dacrcystits. Among 39 isolates of Gram negative bacilli, E.coli(7.62%)  and Klebsiella species(10.26%)  were found to be ESBL producers in chronic dacrocystitis.

Conclusion: Stahylococcus aureus was the predominant organism isolated from acute and chronic dacrocystitis. Gram positive cocci from both acute and chronic dacrocystitis were highly susceptible to cefazolin and vancomycin. Efficacy of amikacin was high towards Gram positive and Gram negative bacteria.