Contaminated ophthalmic solutions represent a potential cause of avoidable ocular infections. Ophthalmic solutions used for both diagnostic and therapeutic purposes have been found to be contaminated with bacteria pathogens and to be associated with ocular infections.Published rates of bacterial contamination in ophthalmic solution bottles are reported to be anywhere from 2.3% to 70% and commonly isolated bacteria include coagulase-negative Staphylococcus, Staphylococcus aureus, Pseudomonas, Bacillus, Proteus, Haemophilus, Enterobacter, Serratia, and Klebsiella spp. Infections of the eye, from contaminated medications or other possible reasons, can rapidly damage the important functional structures and may lead to permanent vision loss and blindness. Serious eye infections such as bacterial keratitis and endophthalmitis were found to be associated with the use of contaminated topical medications
Bacterial keratitis refers to bacterial infection of the cornea and can cause corneal opacity and perforation, which leads to severe visual loss and blindness. It is the leading cause of monocular blindness in the developing world.
The common risk factors for infectious keratitis include contaminated ocular medications, contact lens wear, recent ocular surgery, preexisting ocular surface disease, dry eyes, lid deformity, corneal sensational impairment, chronic use of topical steroids, and systemic immunosuppressant.
Endophthalmitis is an infection and inflammation of all internal and external structure of the eye ball that potentially is the most devastating of ocular infections and a vision-threatening ocular emergency that mandates immediate and aggressive antibiotic therapy. During infection, irreversible damage to delicate structures of the eye occurs. Despite aggressive therapeutic and surgical intervention, endophthalmitis generally results in partial or complete loss of vision, often within a few days of inoculation.
Apart from the risk of infection, bacterial contamination of ophthalmic preparations may alter the pH of the preparation and therefore reduce the efficacy of the medication in the treatment of the intended diagnosis.To prevent microbial contamination, most preparations contain preservatives unless the drug itself has an antimicrobial effect. These preservatives are used to prevent or inhibit the growth of microorganisms which increase the risk of infection or degradation of the drug so that sterility is assured at the time of first use and maintained during use. The role of preservatives is not sufficient to ensure the sterility of multi-dose eye drops during their use, and this justifies the need for safer use of eye drop vials.
Available research evidence about the level of contamination of ophthalmic medications is mainly from more developed countries' eye-care settings. One can expect the level of microbial contamination of eye drops in African eye-care settings and its associated consequence to be worse than in the more developed western ophthalmic centers. However, there is not enough research evidence conducted in African ophthalmic care settings so far. To our knowledge, there is no published evidence that described the level of contamination of eye drops in Ethiopian eye-care centers. Therefore, this study attempted to assess the magnitude and pattern of bacterial contamination of multi-dose ophthalmic medications and drug susceptibility pattern at the University of Gondar Hospital, Northwest Ethiopia.
Methods
Study design period and area
A cross-sectional study was conducted on topical ophthalmic medications used by patients at the University of Gondar Teaching Hospital, Ophthalmology Department, from January 2013 to April 2013.
Study population
All topical ophthalmic medications on-use at the Ophthalmology Department, Gondar University Hospital, were the study population.
Nikhil Bhatnagar