UNILATERAL INTERSTITIAL KERATITIS AS PRESENTING SIGN OF OCULAR TUBERCULOSIS :CASE REPORT

Tuberculosis (TB) is a disease that primarily affects the lungs, but may also affect extrapulmonary organs, including the eye.

Mycobacterium tuberculosis may affect any structure of the eye masquerading as several infective as well as non infective entities and the clinical course generally tends to be insidious and chronic.

Ocular surface involvement in ocular tuberculosis (OTB) is uncommon as compared to TB . Corneal involvement in OTB can occur in the form of phylectenulosis, interstitial keratitis (IK), or disciform keratitis .

HOPITAL DES SPECIALITES . RABAT. MOROCCO

We report a 24-year-old female patient presented with the complaint of decreased vision in her left eye since 1 month . There were no systemic complaints, and family history was insignificant.

On examination, best corrected visual acuity  in her left and right eye was 20/63 and 20/20 respectively.

Slit-lamp examination of the left eye showed  hyperemia  ,peripheral corneal opacities  with deep corneal vascularization around the areas of stromal infiltrates and ghost vessels , posterior synechiae , iris nodules; anterior chamber reaction cells 2+, Flare 1+  . Corneal sensation and intraocular pressure was normal. Vitreous was clear, and indirect ophthalmoscopy of fundus was normal .

Slit-lamp and fundus examination of the right eye was unremarkable.

Laboratory investigations revealed raised erythrocyte sedimentation rate (54 mm/hr) and positive tuberculin test  and  interferon gamma release assay   . 

Patient was referred to internist to rule out any active or latent systemic focus of infection, but none was found. Contrast enhanced computed tomography of chest, abdomen, and brain was normal.

 

 Anterior chamber cell grade reduced to 0.5+ cells with residual corneal scarring.

Patient was followed up for a period of one year after completion of antitubercular therapy with no recurrence of ocular disease.

IK refers to the nonsuppurative and nonulcerative inflammation of the cornea presenting as edema, infiltration, and vascularization of stroma in acute phase. Resolution of the inflammation leads to

scarring and thinning of stroma along with  ghost vessels. The most common cause of unilateral IK is herpes simplex virus and that of bilateral IK is idiopathic followed by syphilis.  OTB causing IK is uncommon . 

The diagnosis of ocular TB usually relies upon the indirect evidence along with the exclusion of other differential diagnoses. Our case showed the ocular feature of anterior granulomatous uveitis, and positive tuberculin test and  interferon gamma release assay , and raised raised erythrocyte sedimentation rate suggestive of TB.

OTB can have varied manifestations, and an unusual presentation may delay diagnosis and increase ocular morbidity. Therefore, Mycobacterium tuberculosis must be kept in mind when countering atypical manifestations especially in endemic countries.