|Year : 1953 | Volume
| Issue : 2 | Page : 35-40
Amoebiasis and the ocular tissues
S. M. S. Medical College, Jaipur, India
|Date of Web Publication||15-May-2008|
H J Hathi
S. M. S. Medical College, Jaipur
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Hathi H J. Amoebiasis and the ocular tissues. Indian J Ophthalmol 1953;1:35-40
That amoebiasis can be responsible for some ocular conditions does not seen to be recognised in this country, although the entamoeba histolytica is one of the most common protozoa affecting the intestinal tract in our country.
After experiencing my first case, a case of Mooren's ulcer, across which I stumbled sonic ten years back, I have been keeping in mind the possible effects of Emetine on ocular conditions with and without systemic amoebiasis.
I tried to look up the literature for any known cheers of amoebiasis on the eye but found it extremely scanty. Bacillary dysentery is known to cause iritis and uveitis as a result of toxaemia, but to the best of my knowledge, no mention is made anywhere about amoebiasis and ocular involvement. Duke-Elder is his text. book Vol. 2 p. 1665 mentions about a report by Parrott finding amoeba in the conjunctival sac, in a case of chronic conjunctivitis, with a fatty bulbar conjunctiva and milky fornices. Fuchs mentions about the condition without specification and Elliot in "Tropical Ophthalmology" makes no mention of it at all.
The object of this paper is to report my clinical trials with emetine with a view to suggest that this protozoa is a possible etiological agent in certain intractable conditions where routine treatment fails.
| The Life Cycle of the E. Histolytica|| |
After ingestion of the cysts of the E. histolytica, on de-encystment in the lower part of the small intestines, from one quadrinuclear cyst. four metastatic trophozoites arc produced. These trophozoites are very motile and penetrate the intestinal mucosa by means of their amoeboid movement and by the cytolytic action of a substance (enzyme). which they secrete, which dissolves the cells of the epithelium. They multiply by binary fission and produce the lesions of amoebiasis. Those trophozoites that remain in the intestines or return to it after penetrating into the tissues become rounded and eventually form cysts which are extruded on defaecation. In acute dysentery with soft stools the trophozoites which are comparatively non-infective are extruded, whereas pasty and hard stools of symptomless carriers contain the mature cysts which constitute real danger in contagion and dissemination of the infection.
The mechanisms of transmission, particularly in India, may be
(1) food and water contamination,
(2) handling of food by infected persons,
(3) contamination by means of excreta of flies and cockroaches,
(4) use of human dried excreta as manure and cakes for burning as fuel, and
(5) lack of personal hygiene and overcrowding in residences.
Out of these the likely ones to affect the human eye are the last three factors.
In amoebiasis, acute toxaemia like that in Bacillary dysentery does not occur. Amoebiasis and Bacillary infection may coexist. The affections of liver, lung and brain arc brought about by formation of emboli leading to amoebic abscesses in these regions.
| Case Reports|| |
In the past ten years I have treated with good results 28 cases with emetine. some of which cases I have followed for a long time, which form the basis of this paper.
My first case was of an elderly man of 60. He had corneal ulceration with intense lacrimation and photophobia. Weeks passed and he would not improve under the usual treatment. Other expert opinions were taken and finally it was diagnosed as a possible vase of Mooren's ulcer, almost symmetrical in both the eyes. Cauterization was advised which the patient refused. Routine laboratory examinations of blood and urine were done and found negative. History pertaining to systemic disorders was negative, excepting that the patient, was dyspeptic (a vague yet important symptom of amoebiasis in this part of the country).
Some four months later the patient suffered front dysentery and the physician put him on emetine injections, with my knowledge and consent. With the third injection the patient reported that his eye condition in particular seemed to improve and he could Open his eyes. The course of emetine injections was completed. In about three weeks both the ulcers healed and were replaced by thin scar, the vision at the end of the treatment being R.E. 6/36. L.E:. 6/24. The patient is still living and enjoying his seventh decade of life.
The cases that are reviewed here can be divided into four groups.
Group I. These comprise a group of six female patients ranging in age
from 6 to 30 years and suffering from recurrent kerato-conjunctivitis, which did not respond to antibiotics, chemo-therapeutic drugs and other routine measures. In these cases, examination of stools in five cases showed the presence of entamoeba or its cysts. Emetine was given with complete recovery,
Group II. A group of five patients in whom the sclera, the episclera and the iris were the main affected tissues. Four cases showed either a bilateral or unilateral infiltration of the sclera and episclera with recurring exacerbations. Stool-examination in these four cases showed definite E. histolytica. The case that had iritis also had an allergic type of dermatitis. There was history of' dysentery in this case, but stool-examination was not done. Emetine therapy put a stop to the recurrence of inflammation in the cases in which the sclera was involved. The iritis case having improved both in his iritis and dermal condition did not report again.
Group III. These comprise a mixed group of ten cases of ulceration of the cornea with a certain degree of conjunctivitis. When routine treatment failed, I put them on emetine injections with amelioration of symptoms. The diagnosis was supported by an examination of the stools which showed E. histolytica in seven cases. Three typical case histories are given below.
A young compounder aged 30, showed a faint cloudiness of the left cornea with breaking up of its superficial layers_ to form an ulcer. The skin of the upper lid had mall pea-sized eruptions. During the five months that he was under treatment all relevant investigations were carried out, which proved to be of no help in establishing an etiology. He gave a vague history of dysentery. He was also asthmatic. Anti-allergic remedies seemed to give him temporary relief. I considered the possibility of amoebiasis although no entamoeba were found in the stools, and resorted to emetine. He made a rapid recovery, left the hospital and was hack at work within a fortnight of starting of emetine treatment. He had instructions to return immediately should the condition recur and six months later he carne back with slight conjunctiva) irritation. Emetine was tried again. It is now over a year, the man is in good health and has good vision, 6/12 with correction.
A Rajput Hindu male aged 50, well built, suddenly developed a sore eye and blurring of vision, all inside of 5 days. There was a definite history of having suffered front dysentery for a week in mild form just a few days before the eyes became sore. The patient had lost his left eye a year and a half back probably under similar conditions. There was an entire corneal involvement due to ulceration, with a 2 lour. strip of hypopyon. Examination of the stool was done and E. Histolytica and E. Coli were found in abundance. Emetine was started and the ulcer healed and when examined three months later. there was only a slight haze in the lower third where a thin opacity still remains. Vision was restored to 6/18.
A Mohamedan male aged 56 with a hypopyon ulcer in both the eyes, was subjected to a complete investigation. Stools revealed E. Histolytica. This was his third attack during the past two years, and the left eye in particular was almost lost. He was weak and anaemic. Emetine was given for amoebiasis along with stovarsol and carbarsone. Liver extract and Protein Hydrolysate were given for his anaemia and hypoproteinaemia. The ocular condition healed completely but with only light perception.
In all these cases topical use of penicillin, atropin drops and carbolisation of the ulcers were done routinely for the first five days. Secondary sepsis seemed to clear but the healing did not set in. Usually improvement started with the third injection of emetine going on to complete healing in ten days.
Group IV This group consists of seven out-door patients, of which five complained of lacrimation and intense photophobia with no corneal or iris involvement, and two gave a history of headache with mild conjunctivitis. Four of them gave history of having suffered from mild or severe forms of dysentery. All were put on emetine after the usual treatment had failed, and were soon relieved. Examinations of the stools were not done in these cases, neither could the patients be traced after the treatment. Under the circumstances these cases cannot be said to be proved cases, and their etiology is only a matter of sup position from the results achieved front emetine therapy.
| Discussion|| |
Our observations cover 28 cases, 15 males and 13 females. Treatment with emetine was started, (1) if there was a definite history of dysentery in the near past, or (2) where an amoebic infection was suspected after the routine treatment had failed to produce any improvement within five days of treatment.
In all the 28 cases improvement was noticed after the third injection of emetine. A11 of them were rendered symptom-free by the tenth day when emetine was discontinued, and the treatment was continued with stovarsol, carbasone and general treatment to combat the dehydration and ypoproteinaemia in the more severe cases. In the majority of cases response to treatment was good. There was a tendency to recurrence in three cases which could be easily controlled by a fresh course of emetine. Two cases treated with emetine which had made a rapid recovery, had a similar condition previously, when response to treatment without emetine was not so rapid. Two cases where emetine treatment was withheld after three injections, showed a tendency to relapse after the previous improvement. With recommencement of emetine after five days, the ulcer started healing again and completely healed within ten days.
In the twenty cases in which stools were examined, sixteen were found to be positive to E.histolytica, though in three cases the examination had to be repeated. In the eight cases where stool examination was not done, the amebic nature of the infection could only be presumed from the improvement in the clinical condition on changing from the routine treatment to emetine treatment.
From the four groups that have been classified above, it will be seen that ocular lesions can be of two types, Groups I and II where there are non-ulcerative but allergic types of lesions, and Group III and IV where there arc ulcerative lesions of the cornea, and affections of the conjunctiva, where perhaps a local involvement of the tissues by the E. histolytica may be present.
E. histolytica is not known to produce toxins which are liable to cause allergic ocular manifestations. However the first two groups definitely suggest some kind of toxemic infection. Whether the toxins belong to the protozoa themselves or these toxins arc from some more common allergising agents e.g. pyogenic or tubercular foci of infection, it would not be possible to prove, at least in our hospital, where such facilities do not exist. It would be interesting however, if an antigen can be prepared and some kind of serological test devised for testing allergy against the E. histolytica.
In the second two groups the affections seem to be definitely local, and in view of the only reported instance where entamoeba histolytica was discovered in the conjunctival sac (Parrott) it Would be interesting to study the conjunctival smear for the presence of the Entamoeba. In the present series the conjunctival smear has been suggested only as a result of this preliminary study. Our future study will include this investigation of the conjunctival sac. However, as E. histolytica, because of its lytic action on the mucosa penetrates into the submucous tissues, its detection in the conjunctival cul-de-sac is not going to be easy. In the case of the corneal ulcers, the difficulty, may not prove to be so great, and the scraping of a corneal ulcer is more likely to yield a positive result.
The following questions suggest themselves at this juncture.
(1) In the absence of demonstration of E. histolytica in the conjunctival sac, can these cases be considered as representing ocular manifestations of amoebiasis?
(2) Can the amoebiasis be only an incidental or activating factor in these otherwise simple affections of the conjunctiva and the cornea ?
(3) Can the effect of emetine be non-specific ?
(4) If we consider these clinical manifestations as a local affection of the ocular tissues or a metastatic abscess formation in cases of hypopyon, by what route do the entamoeba get there?
In the present state of our study, scientifically speaking we cannot say that what we have described are ocular manifestations of amoebiasis, and for that reason the title of our paper remains as "Amoebiasis and the Ocular Tissues". However, the history of dysentery, demonstrations of entamoeba histolytica in the stools in the majority of cases and the rather dramatic effect of emetine therapy after an unsuccessful routine treatment suggests more than a probability of these being ocular manifestations of amoebiasis.
The possibility of amoebiasis acting as an debilitating or an activating factor reduces amoebiasis only to a second place in the etiology of these ocular manifestations, but in no way does it reduce the importance of this subject, namely amoebiasis being directly or indirectly responsible for these manifestations. The beneficial effects of emetine give ample testimony for this trend of thought.
The question whether emetine acts specifically can best be answered by the case of Mooren's ulcer, and the case of the young compounder, reported in this paper. When a case is treated for over four months with all types of remedies, specific and non-specific without any effect, and then suddenly shows improvement with three injections of emetine, it would be unfair to call this improvement non-specific or due to chance.
The possibility of these conditions being allergic in nature has already been discussed with regards to Group I and II. Whether amoebiasis plays a primary role in this allergy or a secondary one by precipitating an allergic reaction from other circulating toxins will have to be proved .
In the case of conjunctival and corneal ulcerative affections, these lesions could in all probability be due to an actual infection by the presence of these protozoa. It remains to be proved whether such is the case. Assuming that the entamoeba do get there, in what way can they get there from the alimentary tract?
Two ways are possible (1) through the blood stream and (2) by direct transfer.
It is well known that the entamoeba can lie latent in the human being, either in the intestinal canal or in the liver by gaining access to it through the portal circulation. However we know of no lesions caused by metastasis of the protozoa except in the case of liver, lung and brain, and it is unlikely that such metastasis takes place in the conjunctival sac.
This leaves us with the other alternative of considering direct transfer. Such a possibility is always there especially among people living in unhygienic places and who perhaps have no soap even to wash their hands after attending to their toilet. Guidance as to proper hygiene is needed in these cases, and it should be easy to eradicate or at least minimize the chances of infection from this source.
In the case of hypopyon ulcers there is a possibility of a metastasis in the ciliary body, comparable to an amoebic liver abscess or brain abscess. If such metastatic infection is possible one would expect to see a hypopyon without a corneal ulceration or an endophthalmitics. As all of these cases had ulceration of the cornea, it is more probable that amoebiasis acted as a debilitating factor increasing the virulence of a corneal infection several folds to cause a hypopyonkeratitis.
However the possibility of a metastatic infection lying latent in the ciliary region flaring into activity with a corneal ulcer in a debilitated person cannot be discounted.
| Summary|| |
(1) Reports of 28 cases are grouped under four groups.
(a) Non-ulcerative lesions of the cornea.
(b) Affections of the sclera. episclera and iris.
(c) Ulcerative lesions of the cornea.
(d) Affections of the conjunctiva.
(2) Sixteen of the twenty cases in which the stool examination was done showed the presence of E. histolytica and/or their cysts.
(3) In four cases where the stool examination was negative, and in eight where it was not carried out, from the rather dramatic improvement that took place after the third injection of emetine onwards, where previous routine treatment had failed, one is tempted to assume the presence of an amoebic infection.
(4) Three possible ways of affection are discussed.
(a) an allergic manifestation.
(b) metastasis through the portal and systemic circulations and
(c) by Local transfer from the anus.