|Year : 1990 | Volume
| Issue : 1 | Page : 30-32
Evaluation of topical povidone-iodine versus gentamycin in staphylococcus coagulase positive corneal ulcers-An experimental study
GK Sharma, JK Goyal, Usha Sharma, GK Chandak, LK Nepalia
JLN Medical College, Ajmer, India
G K Sharma
Department of Ophthalmology, JLN Medical College, Ajmer
Source of Support: None, Conflict of Interest: None
Povidone iodine was found highly effective in controlling the infection and reducing the period of morbidity caused by experimentally produced staphylococcal coagulase positive corneal ulcers in 50 eyes of rabbits in comparison to Gentamycin sulphate. Povidone-iodine was also found to be safe, without any adverse reaction. Hence it can be considered for use in human beings for effective control of corneal infections.
|How to cite this article:|
Sharma G K, Goyal J K, Sharma U, Chandak G K, Nepalia L K. Evaluation of topical povidone-iodine versus gentamycin in staphylococcus coagulase positive corneal ulcers-An experimental study. Indian J Ophthalmol 1990;38:30-2
|How to cite this URL:|
Sharma G K, Goyal J K, Sharma U, Chandak G K, Nepalia L K. Evaluation of topical povidone-iodine versus gentamycin in staphylococcus coagulase positive corneal ulcers-An experimental study. Indian J Ophthalmol [serial online] 1990 [cited 2020 May 28];38:30-2. Available from: http://www.ijo.in/text.asp?1990/38/1/30/24550
| Introduction|| |
Corneal infections caused by the virulent strains of bacteria such as staphylococcus aureus, pneumococci and gram negative coliform group, are generally rapidly progressive, severe and result in considerable, if not total destruction of the eye. Attempts to control these infections by the use of antibiotics have not been uniformly successful. Mahajan  reported that resistant strains have developed even against most potent broad spectrum antibiotic like Gentamycin. Bhargava  found topical Povidone- iodine to be effective in bacterial conjunctivitis without any toxicity or side effects, whereas a few others have studied the efficacy of various dilutions of it. This prompted us to find out the efficacy of Povidone-iodine in experimentally produced bacterial corneal ulcer and its comparison with gentamycin.
| Material and methods|| |
Staphylococcus coagulase positive isolates were used to infect the raw area produced on both corneas of rabbits. These organisms were subjected to an in-vitro sensitivity test to Povidone-iodines and Gentamycin (0.1 % and 10 49 disk concentration respectively). The zone of inhibition was recorded in millimeters and interpreted on the lines of recommendations made by Bauer . Both the eyesof rabbits after topical anaesthesia were prepared by cutting through the corneal disk from central area of 5 mm diameter with a thickness of 0.2 mm with the help of Castroviejo's corneal trephine.
Two drops of 18 hours culture broth of the above said organisms were put in each eye and these eyes were examined after 48 hours of innoculation, for the extent and density of corneal ulcer as advocated by McMeel . The subject matter of the study comprised of 50 eyes of 25 healthy rabbits where the right eye constituted the test group which were treated with 0.1 % PVP-I drops at hourly intervals and 5.0% ointment at night. All the left eyes constituted the treated control group where Gentamycin Sulphate 0.3% eye drops were instilled every hour and the ointment with the same strength at night. Atropine sulphate 1 % ointment was applied once daily in both the groups. Before the start of the treatment an initial record on inflammatory signs; discharge area and density of infiltration were recorded as advocated by Gordon sub and Bohigiam  where a numerical was asigned to a particular grade of intensity of a sign, for the purpose of statistical evaluation.
After such record of signs, the treatment in both the groups was started and continued till the complete clinical cure was achieved and the above said signs were recorded every day, to evaluate the efficacy of drugs in question.
| Observations|| |
The observations of the study are summarised and tabulated in [Table - 1][Table - 2][Table - 3][Table - 4][Table - 5]. The abbreviations used in the tables are T = Testgroup, C = Treated control group, The number of cases in each group are 25.
| Discussion|| |
Gentamycin has been found to be an effective antibiotic for the control of ocular infections in the last few years. At the same time it is also known to have certain ocular and systemic side effects whereas Povidone-iodine a recently proved antiseptic agent now used for surgical preparation of skin is claiming its use, in controlling ophthalmic infections also. It has also been studied that more dilute solutions of Povidone-iodine, provide faster and higher concentration of free iodine, giving it a potent antibacterial activity as reported by Merkalman et a 17. This prompted us to compare the efficacy of 0.1 Povidone-iodine to 0.3% Gentamycin Sulphate eye drops in the control of experimentally produced staphylococcal corneal ulcers in rabbits.
Effectivity of both the drugs in controlling staphylococcal coagulase positive infection was first compaired by an in-vitro study where, statistically significant higher (P<0.001) mean zone of inhibition was observed with Povidone-lodine in comparison to Gentamycin Sulphate [Table - 1].
In vivo study showed rapid diminution of congestion in the test group in comparison to treated control group. This was statistically significant (P<0.01) on second followup [Table - 2].
The reduction in the amount of discharge was faster in test group where it was absent on the third day. In the treated control group it reduced gradually being absent on the fourth day. These observations showed that povidone iodine has a significant role (P 0.05) in reducing the discharge in comparison to Gentamycin [Table - 3].
The area and density of infiltration also showed more rapid disappearance in the test group as compared to the treated control group. The corneal infiltrates were not visible after nine days in the test group whereas they disappeared on the 13th day in the treated control group. Statistically significant values (P < 0.05) were recorded on the seventh day proving the superiority of Povidoneiodine over Gentamycin in the control of inflammatory process [Table - 4].
When the complete clinical picture (total inflammation score) was considered for comparison we observed a rapid control over the signs of the disease in the test group than the treated control group. The complete cure was achieved on the tenth day in Povidone-iodine treated group and on the 13th day in gentamycin group. However statistically significant (P<0.005) observations were found on the seventh day showing a better control over the pathological process from that day onwards by Povidone-iodine 0.1% in comparison to Gentamycin 0.3% eye drops [Table - 5].
Hence it has been statistically evaluated that Povidoneiodine not only controlled the inflammatory signs effectively but also reduced the period of morbidity proving its superiority over Gentamycin sulphate for the treatment of staphylococcal coagulase positive corneal ulcers. Further, no side effects or any signs of chemical irritation or toxicity were noticed in any of the rabbits. This has further opened its avenues for its trial in human beings, for the control of such infections of the cornea.
| References|| |
Mahajan V.M.,Brit.J.Opthal, 67,191,1983.
Bhargava M, Thesis for M.S.(Ophthal).1987.
Bauer W.W.,KirbyW.M.M.,Sherri J.C.and Truck M,Am. J. Pathol,21:93.1968.
McMeel J.W..Am.J.Ophthal, 51:391,1961.
Gordon, D.. Am.J.Ophthal..69:2:300,1970.
Bohigian,G,Okumoto,M.,Valcuton M, Arch. Ophthal.86,432,1971.
Berkelman,R.I..Holland B.w.,Anderson R.I.,J.Clin. Microbiol,15:635.9,1982.
[Table - 1], [Table - 2], [Table - 3], [Table - 4], [Table - 5]