|Year : 1973 | Volume
| Issue : 4 | Page : 185-189
Toxoplasmic uveitis in South India
PN Srinivasa Rao, KN Achyutha Rao
Depts. of Ophthalmology and Microbiology, Kasturba Medical College, Manipal, Mangalore, India
P N Srinivasa Rao
Depts. of Ophthalmology and Microbiology, Kasturba Medical College, Manipal, Mangalore
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Srinivasa Rao P N, Achyutha Rao K N. Toxoplasmic uveitis in South India. Indian J Ophthalmol 1973;21:185-9
| Introduction|| |
Toxoplasma gondii an ubiquitous protozoan parasite, causing both congenital and acquired human infections, can manifest either as systemic or a localised lesion. As a cause of eye infections, this is not commonly thought of, hence there have been few reports of this in our country. Probably the first case of proved protozoan human eye infection was reported by JANKU.  He demonstrated the protozoan in the retinal granulomatous tissue, removed from a threeyear child fatally infected with hydrocephalus.
| Material and Methods|| |
Kasturba Medical College and Hospital of Manipal is located in a village on the west coast of Mysore State, 60 kilometers north of Mangalore, and at an elevation of approximately 350 meters. It caters to the needs of patients from an area about 200 kilometers around it.
All the cases of uveitis, attending the ophthalmic department of the Hospital were subjected to the following tests routinely: (1) Haemoglobin percentage, (2) Total leucocyte count and differential count, (3) E.S.R., (4) Routine blood picture for any abnormal R.B.C., W.B.C., or parasites, (5) Agglutination test for brucellosis, (6) Mantoux test, (7) X-ray chest, (8) X-ray sacroiliac joints and X-ray sinuses.
A provisional diagnosis was made, as non-granulomatous or granulomatous iridocyclitis, central choroiditis, acute or healed, and disseminated choroiditis, etc., depending upon the clinical , findings.
A routine medical check-up was made, by a consultant physician, who understands the problem of uveitis. E.N.T., dental, dermatological and orthopaedic consultations were made only if and when necessary.
A specific diagnosis was made, when the clinical or laboratory tests favoured the same. These were eliminated from our list and then the rest were classified as "Uveitis of undetermined origin".
Serum from 57 cases of uveitis of undetermined origin during the period of 22 months (15th December, 1969 to 15th October, 1971), were tested for toxoplasmosis by haemagglutination test in I.C.M.R. toxoplasma reference Laboratory at A.I.I.M.S., New Delhi. An analysis of cases with positive results will be presented.
| Results and Comments|| |
The haemagglutination test for toxoplasmosis was positive (titre 1/64 and above) in 11 out of 57 cases of uveitis of unknown etiology.
The diseases and the dilutions in which haemagglutination tests were positive are tabulated in [Table - 1].
From the above table, we infer that a percentage of population in this local set-up is infected by toxoplasmosis. Since these individuals are having uveitis of undetermined origin, because of the high titre with specific haemagglutination test, these may be attributed to toxoplasmosis.
The break up of positive cases is shown in [Table - 2]:
From the above Table we infer:
(a) Most of the positive cases belong to the group of central choroiditis with or without generalised uveitis. We feel that, atleast in southern India, toxoplasmosis is a possibility in cases of central choroiditis;
(b) Cases of recurrent vitreous haemorrhage are too few to make any comment. But, the case, which was positive, is certainly interesting. The patient has gone completely blind in both eyes in spite of the prolonged treatment with corticosteroid and antitubercular drugs (elsewhere, before he came to us);
(c) Out of thirty-nine cases grouped under iridocyclitis, 5(13%) showed positive response to haemagglutination test, On a close scrutiny of these case sheets again, we found no other specific clinical findings by which we could sort out these cases. Hence, while toxoplasmosis may be an etiological factor in these cases of iridocyclitis, we have no definite clinical picture by means of which we could identify them;
(d) It is interesting to note that toxoplasmosis may not be an etiological factor in cases of disseminated choroiditis. Out of 5 cases, not a single case was detected as positive by haemagglutination test;
(e) Out of five cases of central choroiditis in which H.A. test was positive, four were in adults and it was an acute episode in all of them. In three of them, it was unilateral. We strongly feel that, in cases of acute macular choroiditis in adults, toxoplasmosis is a possibility in South India. The remaining single case was a 11-year old boy and it may be an old healed lesion due to congenital toxoplasmosis;
(f) It is interesting to note- that systemic examination by a competent consultant who was interested in toxoplasmic infection, was not contributory. However, out of 11 patients, one patient gave a history of recurrent attacks of jaundice once a year for 3 years, the last of which was associated with joint-pains. Could this jaundice be related to toxoplasmic infection?
(g) Out of the 11 patients, who had positive H.A. test, we could follow only 4 cases to date. The details are shown in [Table - 3]. The cases of acute macular choroiditis were given chloromycetin and sulphadiazine in full doses followed two days later by corticosteroids.
It looks as though, in 2 cases out of 5 cases of acute macular choroiditis of suspected toxoplasma origin, we have obtained favourable results with systemic chloromycetin, sulphadiazine, followed by corticosteroid, multivitamins and vasodilators. No comments on these cases are offered.
| Discussion|| |
The recognition of the organism is, of course, a certain means of diagnosis, but this is usually available only on histological examination of the enucleated eye. Only occassionally has the parasite been isolated from the aqueous or sub-retinal fluid during life-DUKE-ELDER. 
Isolation of the organism from lymph nodes have occasionally helped in diagnosis, specially in acquired cases of toxoplasmosis MALIK et al,  INDER SINGH et al. 
In the absence of isolation of organism, the diagnosis becomes presumptive and depends upon typical clinical picture and certain laboratory tests.
Among the laboratory tests, SABIN AND FELDMANS , dye test and haemagglatination test are the most reliable. However, their results should be interpreted, in the light of common occurrence of positive results, up to 60 precent of the clinically unaffected general population. Diagnosis, therefore, should never be based on these tests alone, but only when they are accompanied by the presence of a typical lesion. 
According to Thomas E. VAN METRE,  the characteristic eye lesion produced by toxoplasmosis is focal exudative retino choroiditis.
SANTOK SINGH  reported one case of congenital toxoplasmic chorioretinitis and one case of a carrier proved by serological tests. MALIK, GUPTA AND OM PRAKASH  in a series of 256 cases of uveitis found 8.5% to be due to toxoplasmosis. They found excellent correlationship between the dye test and haemagglutination test. There are a few reports on the subject of Toxoplasmosis from this country. RAWAL, JHALA AND PATEL  found a positive dye test in all the 7 cases of chorio-retinitis investigated.
It will appear that a presumtive diagnosis of toxoplasmosis can be returned by clinicians in a sizeable percentage of cases of uveitis of unknown etiology if haemagglutination test is carried on, if necessary, at a far off laboratory. Though this is a small study it does indicate that toxoplasmosis is an, important etiological agent for central choroiditis, in adults.
| Summary|| |
Haemagglutination-test was carried out in 57 cases of uveitis of undetermined origin. 11 of them showed a positive response. It is felt that toxoplasmosis is a definite infection in this part of the country and some of the cases of uveitis may be due to that infection. In particular, it was thought that toxoplasmosis is a distinct possibility in the cases of adult central choroiditis of recent origin.
| References|| |
Duke Elder Sir Stewart: System of Ophthalmology, Vol. IX: Diseases of the Uveal Tract-Henry Kimpton, London (1969), p. 413-438.
Frenkel, J.: Dermal hypersensitivity to toxoplasma antigens (toxoplasmins) Proc. Soc. Expi. Biol. N. Y.: 68: 634, (1948).
Herpert E. Kaufman: In toxoplasmosis with special reference to uveitis edited by A. E. Maumenee. Williams & Wilkins Company, Baltimore, (1962), p. ,77-897.
Inder Singh: Kapila, C. C., Basu, S. M., Verma, R. N., Narasimhan, D., Rao, K. N. A.; Sardana, D. N., Chopra S. K., and Karani, N. D. P.: Haemorrhagic Disease following tick bites - suspected Toxoplasmosis, Lancet, I: 834, 1965.
S. Jacobs, L., Lunde M. N.: Variations in the dye test for toxomplasmosis. J. Parasit. 43: 308 (1957).
Janku: Cas Lek Ces., 62: 1021, 1052, 1081, 1111, 1138 (1923). Cited by Perkins E. S.: Uveitis and Toxoplasmosis, p. 52 and 134, J. & A. Churchill Ltd. London W. I. (1961).
Malik, S. R. K., Gupta, D. K. and Om Prakash: J. All India Ophthal. Soc., 17: 125-138 (1969).
Malik, S. R. K., Gupta, D. K., Prakash, O., and Cherian, A.: Oriental Arch. of Ophthal. 4: 148 (1966).
Rawal, D. B., Patel, R. J., Jhala, H. I.: Proc. All India Ophthal. Soc. 15: 164 (1954).
Sabin, A. B., and Feldman: Dyes as Microchemical indications of a new immunity phenomenon affecting a protozoan parasite, Science, 108: 660 (1948).
Santok Singh: Toxorplasmosis in India. J. All India Ophthal. Soc., 1: 71 (1953).
Van Metre, Thomas E. (1968): `Clinical Methods in Uveitis' edited by Aranson, Samuel B.; Gamble, Charles N.; Goodner, Earnest, K.; O'Connor, Richard, G. P. 103-11.5. The C. V. Mosby Company, Saint Louis (1968).
Warren, J. and Sabin, A. B.: Proc. Soc. Exper. Biol. and Medicine, 51: 11 (1942).
[Table - 1], [Table - 2], [Table - 3]