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| ARTICLES |
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| Year : 1972 | Volume
: 20
| Issue : 3 | Page : 101-108 |
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Mycotic keratitis
P Siva Reddy, OM Satyendran, M Satapathy, H Vijaya Kumar, P Ranga Reddy
The Institute of Ophthalmology, Sarojini Devi Eye Hospital, Hyderabad, A.P., India
Correspondence Address:
P Siva Reddy
The Institute of Ophthalmology, Sarojini Devi Eye Hospital, Hyderabad, A.P.
India
 Source of Support: None, Conflict of Interest: None  | Check |
PMID: 4668484 
How to cite this article:
Reddy P S, Satyendran O M, Satapathy M, Kumar H V, Reddy P R. Mycotic keratitis. Indian J Ophthalmol 1972;20:101-8 |
In a tropical country like India, corneal and conjunctival conditions present one of the major ophthalmic problems. They commonly occur in elderly persons pursuing agricultural occupations and who are often subjected to debilitating conditions which predispose them towards the development of fungal keratitis.
Mycotic keratitis has been recognised as early as in 1879 by LEBER. In the subsequent three quarters of a century sporadic reports have appeared in the literature averaging about one case per year. CHICK AND CONANT[11] in their review of world literature, found that 84 of the 148 reported cases (57 %) appeared between 195 162 and that half of them occurred before the availability of antibiotics or steroids. They concluded that trauma (which had preceded keratomycosis in 77 cases) with or without bacterial infection was the paramount predisposing factor.
The enthusiastic usage of antibiotics and steroids has been tempered in recent years by the development of complications which they invoked. MITSUI AND HANASUSA [30] reported an incidence of 67% of fungal cultures in those eyes put on steroids, as compared to 18% of controls. THYGESON, HOGAN AND KAMURA [38] were the first to report fungal keratitis after treatment with steroids. HAGGERTY AND ZIMMERMAN [19] showed 15 fold statistical increase in fungal infections of the eye. Since then many case reports [4],[7],[16],[17],[18],[26],[28],[29] covering a number of cases have been published, among Indian observers. BALAKRISHNAN [5] 30 cases, SREENIVASA RAO AND RAMAKRISHNA [36] 13 cases of fungal infection out of 40 cases (33% ) of corneal ulcers, AGARWAL AND KHOSLA [1] 6 cases, PUTTANNA [32] , 34 cases, and SOOD RATANRAJ, SHINOY AND MADHAVAN [35] 32 cases, out of 159 cases of hypopyon ulcers, have contributed to the literature on the subject. These authors have focussed attention to the increasing frequency of these infections, the importance of early diagnosis, and the difficulties encountered in therapy.
The present paper deals with the clinical features, diagnosis, culture of the fungi and the response to treatment of mycotic ulcers of the cornea.
| Methods and Material | |  |
The survey of mycotic keratitis has been conducted on both in-patients and out-patients attending the Sarojini Devi Eye Hospital and Institute of Ophthalmology, Hyderabad in the year 1968-69. All the cases of hypopyon ulcers and the ulcers which are not responding to treatment are included in this present series. In every case corneal scrapings were taken from the edge of the ulcers with the help of a platinum loop. A wet mount of the corneal scrapings with 10% KOH and lacto phenol cotton blue stain was prepared and was examined for the presence of fungal elements under the microscope. The corneal scrapings were also innoculated on Sabouraud's medium and on blood agar plates and incubated at room temperature. All the media were examined daily. Slide cultures were prepared to study the morphology of the fungi. The fungal identification of the species was made with the help of a microbiologist.
| Results | | |
Incidence: 75,277 patients attended the Sarojini Devi Eye Hospital during 1968-69. Out of the 600 cases (0.8%) were having ulcer cornea. Out of them 209 (36.5%) had hypopyon out of which 36 (17.3%) were proved to be fungal in origin.
Sex incidence: Fungal keratitis appeared to be a little more common in the males (52.8%) than in females (47.2%) as men are more prone to injury than females.
Age incidence: The maximum age incidence was between 41-60 years41.66 per cent between 41-50 years and 52.8 per cent were between 51-60 years. There was only 1 case, a female, between 31-40 years and 1 case, a male, between 11-20 years.
Occupation:
Out of the 36 cases of fungal keratitis, 20 were agricultural labourers, 7 industrial workers, 4 washermen and 5 house-wives.
Thus the maximum incidence was seen with agricultural labourers (55.5%) in this series.
Associated General Conditions:
It is significant that all the 36 cases had some associated debilitating general condition. Thus 19 were anaemic, 13 had signs of riboflavin deficiency (angular stomatitis, cheilosis and glazed tongue), 2 were diabetic and 2 had focal sepsis. Thus anemias and vitamin deficiencies (88.8%) were the main predisposing causes in our series.
History :
19 cases (52.8%) had a history of trauma to the eyes with vegetable matters. Application of steroids was the next contributing factor - 14 out of 36 (39%). Three cases gave history of the eye being treated with herbal drops and indigenous drugs.
Time interval between the Injury to the Eye and reporting to the Hospital:
55.5% of cases sought medical aid after an interval of 2-3 weeks. This is because of the slow, indolent, torpid, behaviour of the lesion. During this time, the fungal ulcer becomes established.
Appearance of the ulcer cornea:
The typical central greyish elevated ulcer with hypopyon along with satellite infiltrates was seen in 36 cases [Figure - 1] whereas in the other six the ulcer had no satellite infiltrates.
In our series Aspergillus species of the fungus topped the list, the percentage being 50.5. This is one of the commonest fungal organisms giving rise to corneal ulcers. [Figure - 4],[Figure - 5],[Figure - 6],[Figure - 7],[Figure - 8],[Figure 9].
Treatment:
No type of antifungal ophthalmic ointment is available. The ulcer was therefore cauterised with iodine, mydriatic applied, locally, and the eye bandaged. The eye was irrigated gently every day with saline. Nystatin tablets (Mycostatin 500,000 units) one tablet three times a day was given. Secondary glaucoma was controlled with Diamox. Conjunctival hooding was done in intractable ulcers.
Complications:
24 cases out of 36 (66.6%) showed good response to the antifungal treatment.
7 cases (19.44%) of ulcer cornea healed well, but developed secondary glaucoma which responded to Diamox.
5 cases (13.9%) resulted in complications like perforation and panophthalmitis.
| Discussion | | |
After the advent of antibiotic and steroid therapy, for various inflammatory lesions of the eye, fungal affections have become more frequent as is seen in the literature. There is also evidence to show that there has been an increased incidence of systemic fungal infections, after antibiotic or steroid therapy VAN WINKLE, Melvin, Reheins and Tedsuic. LEY experimentally proved that the previous use of steroids facilitated the development of fungal keratitis raising its incidence from 20 to 80 per cent.
In our series of 36 cases of fungal keratitis, 14 patients (36%) gave history of steady and frequent application of steroids and antibiotics to the eyes, before the development of fungal keratitis. Antibiotics enhance the growth of fungus by inhibition of bacterial flora, while steroids facilitate proliferation of the fungus, through interference with the host's antiinflammatory and immune response, permitting the pathogen to become more readily established. (HUPPERT, MCPHERSON AND CAZIN [20] ). These hazards were expressed in 1955, with characteristic eloquence by DUKE ELDER AND GOLDSMITH. [15] SUGA [37] observed that steroids induced corneal hyper-glycemia which is responsible for the development of mycotic keratitis. The ultimate mechanism still remains speculative.
Trauma to the eye by vegetable matter, field dust, swish of a cow's tail while milking (BEDELL [9] ), twigs, thorns, dusty grains, cornstalks, grass reeds, favour mycotic keratitis, as all of them have a generous number of fungal spores. BALAKRISHNAN [5] reported 30 cases in the agricultural labourers. ZIMMERMAN [10] collected 22 cases of fungal keratitis which have followed some injury to the cornea, mostly trivial wounds (abrasion, superficial laceration small foreign body caused by vegetable matter). In our series, 19 patients (52.8%) gave history of trauma to the eye by vegetable matter. Those who denied history of trauma, on careful probing admitted of sustaining minor injuries in the field which they considered too trivial. Most of our cases were agricultural labourers.
PUTTANNA [33] reported primary fungus keratitis after instillation of herbal drops and suggested that the fungi might have been carried by the vehicle of the herbal juice. In our series, only 3 patients (8.3%) tried indigenous treatment in the form of instillation of goat's milk, milky juice of bunyan trees, scratching the eye with grass reeds before the fungal keratitis developed.
Focal sepsis in the form of vaginitis and leucorrhoea, has been mentioned by PUTTANNA [32] as one of the precipitating causes. He recorded several cases in his series of mycotic keratitis with the above history and suggested auto-infection, due to lack of personal cleanliness. In our series of cases, there were 2 muslim ladies observing `Purdah' who had leucorrhoea for over a few months before developing fungal keratitis. In both, Candida albicans was isolated, from the corneal scrapings.
DUKE ELDER [14] stated that the clinical picture of mycotic corneal ulcers is so uniform that it can be conveniently described as a type. A mycotic ulcer presents as a central greyish-white elevated discoid ulcer with irregular fragmented, undermined edges, with a yellow line of demarcation. Satellite infiltrates are typically seen around the edge of the ulcer with pigment clumping. Satellite lesions represent extension of the fungus. Hypopyon is seen even when the ulcer is of small size. The central core presents a laminated appearance with a crumbling surface. Vascularisation is invariably absent and the general course of the lesion is slow and torpid. The centre of the ulcer consists of necrotic material while the fungus is present usually in the edges of the ulcer. (Plate 1)
Histopathological examination with special stains like Gomoris methenamine silver stain, and Gridleys stain shows fungal elements in the corneal stroma.(Plate 2)
KAUFMAN AND WOOD [21] described a few other features of fungal ulcers. In four of their 15 cases, a dense white plaque was visible on the endothelial surface of the cornea. The authors performed an anterior chamber wash and aspirated the material from the area of endothelial plaque and demonstrated Aspergillus. Another sign noted in three of their cases was a white ring in midperiphery of the cornea (the corneal ring).
A wide range of fungi have been known to cause keratitis. GINGRICH [17] has extensively reviewed the world literature on the types of fungi isolated in culture as cause of keratomycosis and found Aspergillus species to be responsible for 25 out of 125 published cases. In his series of 10 cases, Fusarium oxysporium was isolated in 3 cases, Candida albicans in 2, and Nocardias, Actinomycosis bovis, Aspergillus fumigatus and Cephalosporium serrae one each. AGARWAL AND KHOSLA [1] reported 6 cases, wherein Candida albicans and Aspergillus fumigatus two cases each, Candida krusei and Fusarium one each were isolated. PUTTANNA [34] reported 34 cases out of which Aspergillus niger was isolated in the majority of 7 cases. BALAKRISHNAN [5] from 30 cases isolated Aspergillus fumigatus in 13 cases. In our series of cases, Aspergillus niger constituted the majority (18 out of 36 cases) (50.55%). This is in accordance with the findings of GRINGRICH [17] , BALAKRISHNAN [5] and PUTTANNA [32] . Aspergillus infections of the cornea are well known. Both Aspergillus niger (10) and Aspergillus fumigatus (8) produced an identical picture, conforming to the general description. In all the cases, only superficial layers of the cornea were affected. All the lesions were typically ringed with pigment.
Fusarium keratitis: This is a new comer to the list of fungi causing keratomycosis, the first case was observed by GINGRICH[ 17] in 1955. ANDERSON AND CHICK [4] reported 9 cases of which 4 were caused by Fusarium which responded well to Amphotericin B. therapy. There were 5 cases due to fusarium in our series.
Penicillium keratitis: In our series there were 5 cases due to Penicillium species of fungus.
Candida, Cephalosporium and Sepadonium: Each constituted two cases in our series.
Sporotrichos and Rhizopus: Each constituted one case.
The treatment of a fungal ulcer begins with early scraping of the ulcer which is both diagnostic and thera. peutic. A large number of therapeutic preparations have been tried for the treatment of mycotic keratitis. 30% Sodium sulfacetamide iantophoresis, followed by application of organic mercurials topically (Thimersol) by GINGRICH [17] , Iodides by mouth, BARNET AND LEOPOLD [6] PUTTANNA [34] . Topical copper sulphate drops 0.125% Sodium proprionate drops 10%, Copper proprionate ointment PUTTANNA [34] , Nystatin 100,000 units/ gm. ointment, MONTANA AND SERY [31] Amphotericin B ANDERSON, ROBERTS, GONZALE AND CHICK [3] (1959). CHICK HUDDELL AND SHARP [12] used ultraviolet rays with amphotericin B in the form of drops 1.0 mg/ml, Pimaricin, KAUFMAN AND WOOD [21] , Griseofulmin, BATISTA AND FILNO [8] Thiabindazole, BLANK AND REBELL [10] Hamycin, AHUJA, NATH AND NEMA [2] and Cyclohexamide, LYNN [24] . These medical measures may be combined with surgical procedure like mechanical debridement, ANDERSON et a1 [4] Conjunctival hooding, KAUFMAN AND WooD [21] and Keratoplasty, DHANDA [13]
In our experience, in the absence of broad spectrum antifungal antibiotics, Iodine cautery, and deep scraping of the ulcer itself has given satisfactory results in our series of cases. Lamellar keratoplasty was done only at the healed stage of the ulcer and the results are encouraging.
| Summary | | |
- The percentage incidence of Mycotic keratitis in this series is 17.3% among hypopyon corneal ulcers.
- The maximum age incidence is between 41-60 years.
- Debilitating conditions are the main predisposing factors.
- 55.5% cases are agricultural labourers.
- 61.1% cases gave history of trauma to the eye by vegetable matter, and 30.6% of cases, prolonged application of antibiotic and cortisone ointment to the eye. These are the contributing factors, for the occurrence of fungal keratitis in this series.
- Central greyish white elevated disc, shaped ulcer with hypopyon and satellite infiltrates together with pigment at the edge of the ulcer are the characteristic features in the majority of the cases.
- Aspergillus species of fungus formed majority (50.5%) in this series.
- Iodine cautery and deep scraping of the ulcer has given satisfactory results. Lamellar keratoplasty was done only at the healed stage of the ulcer and the results are encouraging.
| Acknowledgement | | |
We extend our thanks to Dr. Mrs. K. Rajyalakshmi, MD., Professor of Microbiology, Osmania Medical College for identifying the species of the various fungi[40].
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[Figure - 1], [Figure - 2], [Figure - 3], [Figure - 4], [Figure - 5], [Figure - 6], [Figure - 7], [Figure - 8]
[Table - 1]
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