Orbital tuberculosis manifesting with enophthalmos and causing a diagnostic dilemma

A 60-year-old woman with no known systemic disease was referred with a hard mass in the left orbit and enophthalmos of two months duration. Differential diagnoses of metastasis from an undetected scirrhous carcinoma and sclerosing nonspecific orbital inflammatory disease were considered and a biopsy was performed. Histopathology demonstrated granulomatous inflammation with fibrosis. Subsequent polymerase chain reaction was positive for Mycobacterium tuberculosis deoxyribonucleic acid. There was no evidence of systemic tuberculosis. The patient was treated with four-drug combination anti-tubercular therapy for 6 months. The mass regressed and there was no local recurrence at two years follow-up. Orbital tuberculosis generally manifests with proptosis or osteomyelitis. However, enophthalmos may be caused by the fibrosing variant. Biopsy with histopathologic and microbioloic evaluation is essential to distinguish it from other more common causes of an orbital mass with paradoxical enophthalmos such as metastatic scirrhous carcinoma and sclerosing nonspecific orbital inflammatory disease.