Chronic unilateral conjunctivitis

Abstract

An 18-year-old man presented with a 1 year history of frequent episodes of redness, itching, and swelling of the upper eyelid of the right eye. Elsewhere, he had been diagnosed with allergic conjunctivitis and intermittently treated with prednisolone acetate and ciclosporin eye drops without relief. At presentation, his visual acuity was 20/20. On examination, lid oedema was recorded and the tarsal conjunctiva was hyperaemic. Double eversion of the right upper eyelid showed ulceration at the upper border of the tarsal plate extending into the fornix (fi gure). On the basis of the history and clinical fi ndings, a diagnosis of ulcerative conjunctivitis, presumably of tuberculous origin, was made. The direct microscopic examination of conjunctival scrapings identifi ed acid-fast bacilli in Ziehl-Neelsen stain. The growth on BACTEC 460 TB culture and Lowenstein-Jensen medium was Mycobacterium tuberculosis. Histopathological exam ination of a biopsy showed features of necrotising infl ammation with several long, beaded acid-fast bacilli. A Mantoux test was positive, with an induration of 30 mm after 48 h. The erythrocyte sedimentation rate was in the standard range and chest radiograph was normal. The patient was successfully treated with isoniazid (15 mg/kg daily), rifampicin (12 mg/kg daily), and pyrazinamide (20 mg/kg daily) for 9 months. There was complete resolution of the ulcerated lesion after 5 months of treatment, with no episodes of recurrence after 2 years of follow-up. Chronic unilateral conjunctivitis has many causes, one of which is tuberculosis. The upper palpebral conjunctiva is most commonly involved (70% of patients), followed by the bulbar (20%) and fornix (8%) conjunctivas. Because of the non-specifi c symptoms, individuals with this disorder are likely to be misdiagnosed and treated for allergic conjunctivitis, as was the case with this patient. Further, routine slit-lamp examination might not expose lesions deep in the fornix, leading to a delayed diagnosis. Patients presenting with chronic unilateral conjunctivitis should be tested for mycobacterial infection, and treating physicians should thoroughly assess fornices and use appropriate histological, microbiological, and molecular methods of diagnosis.