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ARTICLES |
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Year : 1979 | Volume
: 27
| Issue : 4 | Page : 6-8 |
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Various Investigation procedure in the etiology and diagnosis of uveitis
SRK Malik
Sir Ganga Rain Hospital, New Delhi, India
Correspondence Address: SRK Malik Sir Ganga Rain Hospital, New Delhi India
Source of Support: None, Conflict of Interest: None | Check |
How to cite this article: Malik S. Various Investigation procedure in the etiology and diagnosis of uveitis. Indian J Ophthalmol 1979;27:6-8 |
Uveitis has multiple causes that must be identified and treated appropriately. To this day, it has been difficult to define an exact outline of investigative procedures which would serve the purpose of arriving at a definite diagnosis, because each investigative technique has proven fallible in some way or the other. The pathogenesis of the hardcore group of conditions exemplified by chronic non-granulomatous iridocyclitis cases has eluded explanation even by present technique.
Materials and methods | | |
Several methods have been used for the study of the pathogenesis of uveitis e.g.
(a) Isolation of the causative organism from the eye and reproduction of the disease in vitro or establishment of specific therapeutic response.
(b) Observation of specific lesions in patients with an active systemic disease e.g. leprosy, syphilis, sarcoidosis.
(c) Identification of clinical entities in an effort to determine the cause.
In so far as accuracy of method is concerned, the isolation method is exact, but least practical in the study of uveitis. The second method is almost the same, whereas the third although least accurate, is most applicable for a study of uveitis.
Generally, a diagnosis is made after a 'medical survey' of the patient which includes i) a careful elicitation of history, ii) a thorough physical examination followed by iii) serological and other investigations to detect evidence of any past or present illness significant to the ocular complaint.
Besides certain well defined clinical entities (e.g, sympathetic ophthalmia, Vogt-Kayangi-Harada syndrome and Fuch's heterochromic iridocyclitis etc There are some causes of uveitis highly suggestive of specific etiology.
(a) Toxoplasmosis (b) Histoplasmosis (c) Toxocariasis (d) Herpes simplex iridocyclitis (e) T.B. sarcoid and syphilis.
A routine in the examination of every case is now outlined with some of the procedures considered in detail and their advantages or disadvantages discussed. Examination must include:
(A) A complete case history and physical examination.
(B) Clinical appearance of the case-involving a complete ophthalmological examination by:
- Biomicroscopy of anterior segment chamber angle, vitreous, fundus from papilli to ora serrata and pars plana.
- Refraction and ocular tension.
- Exact measurement of tyndall effect and counting the number of cells in anterior chamber by slit lamp photography whenever possible.
- Fundus photography or drawing.
- Fluorescent retinography.
(C) Examination of the patient's serum based on immune mechanism of specific etiological agents.
(D) Aqueous humour studies for:
Demonstration of treponemas either by dark field illumination or by immunofiuorescence technique.
(E) Skin testing: based on hypersensitive skin reaction to specific antigen is relatively easy to conduct, unfortunately these are of doubtful value in helping the diagnosis of uveitis.
(F) General clinical laboratory investigations are only of rare supportive value. However, E.S.R. [Table - 1] often is helpful in giving a direction to the process of diagnosis.
(G) Surgery-biopsies of lymph node, skin, rectum or jejunum if indicated.
This mass of information thus accumulated can then be studied and correlated with the type of ocular inflammatory syndrome. Presumed etiologic diagnosis can be made when a morphologic syndrome is shown to have over 80% correlation with evidence of a specific infection; and ultimately, a specific diagnosis can be made only by demonstration of the organism in the eke of the affected patient.
Serum antibody titres:
Ocular infections seem to provide an inadequate antigenic stimulus for the development of sufficiently high antibody levels in the serum to be of diagnostic value through serological tests. However, rising antibody titre in presence of clinical ocular disease is of significance. It is often a useful practice to try to exclude such diseases as syphilis by conducting a routine S,T'S. [Table - 5].
Though serological test for syphilis remains the most widely used method of diagnosis, evidence of ocular syphilis has been demonstrated in seronegative individuals. Ocular syphilis has been diagnosed by such procedures as demonstration of spirochaetes and Flourescent Treponemal Antibody Absorption test in aqueous samples.
Skin testing:
The high percentage of positive skin tests in clinically normal population and their nonspecificity, reduces their diagnostic potential. They could be mostly screening tests for exposure to the disease. Among the important skin tests in use today are: tuberculin, toxopiasmin and histoplasmin. Montoux is one of the commonest skin test in clinical use [Table - 4].
Aqueous humour studies:
The study of aqueous obtained by taping the anterior chamber has the promise of an invaluable aid in diagnosis. Analysis of aqueous proteins by electrophoresis and stuly of cellular content may throw valuable light on diagnosis. Demonstration of organisms (e.g. Treponema p.) would be diagnostic.
Non-specific tests:
Lately the study of immunoproteins, specially gamma globulins in uveitis has received some attention. The value of such investigations in assessment of clinical cases is not clear.
Autoimmunity:
Though autoimmune process has been suspected in certain types of uveitis, there are no satisfactory clinical methods known to test this hypothesis. Fluoreseein angiography has added a new dimension to the investigative procedures on posterior segment inflammatory lesions. It reveals the state of permeability of blood vessels and the blood aqueous barriers and monitors it during, treatment, thereby providing valuable information on progress of the disease with or without treatment.
A total of 258 patients of endogenous uveitis were investigated fully in the uveitis clinic of the eye department of Lok Nayak Jayaprakash Narayan Hospital, New Delhi. Some of the results are hereby presented in tabular form. [Table - 1],[Table - 2],[Table - 3],[Table - 4],[Table - 5].
Discussion | | |
- Dr. Pati, of Rourkela remarked that in our country both granulomatous and non-granulomatous uveitis is fairly common.
- Dr. Asutosh Sarkar remarked that the uveitis of tuberculosis aetiology is not so common as Dr. Malik has pointed out in his paper,
- Chairman Dr. K.C. Dutta remarked that due to availability of better investigative facilities, the percentage of "unknown aetiology" group of uveitis is decreasing.
[Table - 1], [Table - 2], [Table - 3], [Table - 4], [Table - 5]
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