|Year : 1967 | Volume
| Issue : 1 | Page : 19-22
Hamycin in experimental keratomycosis
OP Ahuja, A Bal, K Nath, HV Nema
Aligarh Muslim University, Institute of Ophthalmology, Aligarh, India
|Date of Web Publication||18-Jan-2008|
O P Ahuja
Aligarh Muslim University, Institute of Ophthalmology, Aligarh
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Ahuja O P, Bal A, Nath K, Nema H V. Hamycin in experimental keratomycosis. Indian J Ophthalmol 1967;15:19-22
The response to treatment of fungus keratitis with the usual broad spectrum antibiotics has not proved satisfactory. In fact, Seligmann (1952 & 1953) and Dukes and Tattenbaughm (1954-55) have suggested that tetracycline potentiated the pathogenicity of Candida albicans. It is unfortunate that the specific anti-fungus drugs like Amphotericin-B are not freely available in India for a wide clinical use.
Hamycin,* manufactured in India, is a new antibiotic claimed to be effective against various fungus infections of skin and ear etc. -- [Atre, Wakankar and Padhye (1961), and Gokhalay, Padhye and Thirumalachar (1961)]. There is, however, no report of its effectivity against corneal lesions of fungus origin.
In view of the above factors, the present experiments were planned to study the effectivity of the drug against fungus infections of the cornea and if found effective, to exploit its use in ophthalmic practice.
| Present Study|| |
Experiments (in vivo and in vitro) were designed to study the effectivity of the drug. The following procedure was adopted:
1. In vivo experiments:
Hydrocortisone ointment (1%) was applied three times a day for 15 days to both the eyes of 20 albino rabbits. Following this, a corneal ulcer was produced in both corneas of these rabbits. The technique of ulcer production was the same as detailed in a previous study (Ahuja and Shukla. 1964). The animals were then divided into two groups (A and B) of 10 rabbits each.
Group -A : Both corneas were infected with Aspergillus fumigatus. Twenty four hours after the production of an ulcer, the right eye was treated by instillations of Hamycin glycerine suspension, every two hours on the first day (in daytime only) and 4 times a day on subsequent days until the ulcer was healed. Glycerine drops were instilled in the left eyes with the same frequency. The left eye served as control.
Group-B: In this group the corneas were infected with a culture of Candida albicans in both eyes. The subsequent procedure was the same as in the animals of group A.
Each eye was examined every day and a record was made regarding the presence and amount of discharge from the eye, conjunctival and ciliary congestion: slough in the floor of ulcer, and fluorescein staining of the ulcer. Ultimate scarring at the site of ulcer after complete healing was also noted.
2. In vitro experiments
Sensitivity of Nocardia asteroids, Aspergillus fumigatus, Monosporium apiospermum, Mucor and Candida albicans to Hamycin was studied on Sabouraud's agar plates. The antibiotic was used in concentrations of 1, 10, 25 and 50 units per c.c. of the culture medium. The plates of each concentration of the antibiotic were lightly inoculated with the test strains of various fungi. These strains were also inoculated on simple Sabouraud's plates (without Hamycin) to serve as controls. The plates were incubated at 37°C and were observed every day for 10 days, for evidence of any suppression of fungus growth.
| Results|| |
In vivo experiments:
The results obtained in the rabbits of group 'A' and 'B' have been summarised in the Table. Also compare the figures on the opposite page.
[t was observed that Hamycin did not have any effect on the course, healing and ultimate scarring of the ulcer in rabbits 256 and 257 of Grout) A. The average duration of the slough in the ulcer floor (6.9 days) and the average period of positive staining (10.6 days) was almost the same as in the control eyes i.e. 6.2 and 10.4 days respectively.
On the other hands, the drug produced a marked irritation in the eyes where used. The amount and duration of the congestion and discharge from these eyes was much more pronounced as compared to the control eyes.
In Group B the irritative phenomenon of Hamycin suspension was seen in these eyes similar to those of group 'A'. However, the drug favourably modified the course and healing of the ulcer in these eyes (rabbits 263 and 265). Hamycin helped in an earlier removal of the slough and led to a quicker healing of the ulcer. In eyes subjected to Hamycin treatment the average duration of the slough and a positive fluorescin staining was 2.4 and 4.4 days respectively, while the respective figures in control eyes were 5.2 and 8.0 days. The ultimate scarring was comparatively more in two of the control eyes as compared to the 'test eyes.'
2. In vitro experiments
There was no suppression or inhibition of growth of Nocardia asteroides, Aspergillus fumigatus, Monosporium apiospermum and Mucor in any of the concentration of the antibiotic used.
Hamycin in the concentration of one unit per c.c. had no effect on the growth of Candida albicans, but the growth was suppressed after 24 hours in higher concentrations. After 48 hours some amount of growth could be seen on the plates containing 10 units of Hamycin per c.c., though the growth was much less as compared to the control. In the concentrations of 25 and 50 units per c.c. the growth was completely inhibited and remained so for 10 days.
| Discussion|| |
Hamycin glycerine suspension produced a marked irritation when instilled into conjunctival cul-de-sac. Although glycerine, the base of the drug, itself is irritating to the eyes, the whole reaction was much more pronounced in the eyes where Hamycin suspension was employed, as compared to controls where glycerine alone was used. It appears, therefore, that Hamycin also has some irritating properties of its own. The drug, in the form employed in the present study, is unsuitable for use in cases of keratomycosis.
Hamycin did not show any antifungal properties except in the case of Candida albicans. Our in vivo experiments revealed that the drug did not affect the course of corneal ulcers infected with Aspergillus fumigatus. However, in Candida albicans infected corneal ulcer, the healing was rapid as compared with the centrol.
The findings of sensitivity tests were in agreement with the in vivo studies in as much as the drug inhibited the growth of Candida albicans while there was no effect seen on the plates inoculated with Aspergillus fumigatus. Also, there was no inhibition of the growth of other inoculated strains i.e. Nocardia asteroides, Monosporium apiospermum and Mucor.
It is concluded, therefore, that Hamycin is not effective against the common pathogenic fungi affecting cornea, except in cases of Candida albicans infections. Even in candida infections the preparation employed in this study is too irritating to encourage its use. However, it may be suggested that the drug can be of value in Candida infections if prepared in a soft, non irritating base for ocular use. Even then the irritation caused by Hamycin itself will have to be reckoned with.
| Summary|| |
1. Effectivity of Hamycin glycerine suspension was studied in rabbits, in the treatment of experimentally produced corneal infections by Candida albicans and Aspergillus fumigatus. The drug appeared to be effective in infections with the former but not with the latter. The preparation appeared to be very irritative.
2. Sensitivity of Nocardia asteroides, Aspergillus fumigatus, Monosporium apiospermum, Mucor and Candida albicans to Hamycin, was studied in concentration of 1, 10, 25 and 50 units per c.c. of the culture medium on Sabouraud's agar plates.
3. The drug did not inhibit the growth of Nocardia asteroides, Aspergillus furnigatus, Monosporium apiospermum, and Mucor. However, the growth of Candida albicans was increasingly inhibited in concentrations of 10, 25, and 50 units of Hamycin per c.c. of culture medium.
| References|| |
Ahuja O.P. & Shukla B. R. (1964): Amer. J. Ophthal., 58: 664.
Atre, W. G., Wakankar, P. S. and Padhye. A. A. (1961): Hindustan Antibiot. Bull., 3: 172.
Dukes, C. D. & Tattenbaugham I. S. (1954-55): Antibio. Ann., 1954-55. N.Y. Med. Encyclo. pp. 674.
Gokhalay, B.B., Padhye, A. A. and Thirumalachar, M. J. (1961): Hindustan Anti-biot. Bull. 4: 34.
Seligmann, E. (1952): Proc. Soc. Exp. Biol. & Med., 79: 481.
Seligmann, E. (1953): Proc. Soc. Exp. Biol. & Med., 83: 778.
[Figure - 1]
[Table - 1]