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Published on: May 1, 2021
Study of Conjunctival Microbial Flora in Patients of Intensive Care Unit
Kadambari Ramani1, Subashini Kaliaperumal1, Sandip Sarkar1
1Department of Ophthalmology, Jawaharlal Institute of Post Graduate Medical Education and Research, Puducherry, India.
Purpose:
The objective of the study was to evaluate the type of conjunctival microbial flora in intensive care unit patients and their antimicrobial sensitivity pattern.
Methods:
A total of 272 samples (conjunctival swabs) were taken from patients in various intensive care units and sent for culture and sensitivity. An ocular examination was done to look for lagophthalmos, conjunctival discharge, exposure keratitis, and corneal perforation.
Results:
Majority (82.1%) of the samples showed at least one microbial isolate while 29 (10.7%) samples showed multiple microbial growth. The most common microbes were coagulase negative Staphylococcus spp. (41.5% of isolates), diphtheroids (11.0% of isolates), and Staphylococcus aureus (9.6% of isolates) which are the usual commensals of the ocular surface. Of the other microbes isolated, Pseudomonas aeruginosa (4.0%) was the most common. Eighty-four percent isolates of coagulase negative Staphylococcus sp., 81.8% isolates of diphtheroids and 100% isolates of Staphylococcus aureus were penicillin resistant. All isolates of Enterococcus fecalis were sensitive only to vancomycin. Two hundred and twenty eyes (80.9%) had varying degrees of lagophthalmos. Nineteen (7.0%) had severe corneal exposure changes leading to infectious corneal ulcer and perforation in all of them.
Conclusions:
The isolates in patients of intensive care units were no different from the normal conjunctival flora though few pathogenic organisms such as Pseudomonas aeruginosa and Acinetobacter sp. were also isolated. Most of the isolates were penicillin resistant. This knowledge will help take appropriate prophylactic measures to contain ocular infections in the intensive care units.
Insights
Intensive care unit patients often have normal conjunctival flora, but some pathogenic bacteria are present. Most isolates show penicillin resistance, necessitating targeted prophylactic measures against ocular infections.
Area of Science:
- Ophthalmology
- Microbiology
- Infectious Diseases
Background:
- Intensive care units (ICUs) harbor patients susceptible to various infections.
- Conjunctival microbial flora can be a source of ocular infections, especially in vulnerable patient populations.
- Understanding the specific microbial landscape and resistance patterns in ICU patients is crucial for effective management.
Purpose of the Study:
- To characterize the conjunctival microbial flora in patients admitted to intensive care units.
- To determine the antimicrobial sensitivity patterns of isolated microorganisms.
- To identify potential risk factors for ocular infections in this patient group.
Main Methods:
- Collected 272 conjunctival swab samples from ICU patients.
- Performed microbial culture and sensitivity testing.
- Conducted ocular examinations to assess for lagophthalmos, discharge, keratitis, and corneal perforation.
Main Results:
- 82.1% of samples yielded microbial growth, with coagulase-negative Staphylococcus spp. being the most common (41.5%).
- Pathogenic bacteria like Pseudomonas aeruginosa (4.0%) were also isolated.
- High resistance rates to penicillin were observed among common isolates; Enterococcus fecalis showed sensitivity only to vancomycin.
- Significant rates of lagophthalmos (80.9%) and severe corneal exposure (7.0%) were noted, leading to infectious corneal ulcers and perforation in affected eyes.
Conclusions:
- Conjunctival flora in ICU patients largely resembles normal flora, but includes concerning pathogens.
- Widespread penicillin resistance among isolates is a significant finding.
- Knowledge of these microbial patterns and resistance is vital for implementing effective prophylactic strategies against ocular infections in ICUs.
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