To accentuate the importance of suspecting CNS TB in afebrile patients from endemic areas presenting with proptosis and ophthalmoplegia.
CNS TB represents 15% of all cases of tuberculosis. Orbital apex syndrome, a combination of proptosis and dysfunction of the cranial nerves II, III, IV and VI and V1 is a rare presentation of CNS TB that mimics other noninfectious conditions, especially in the absence of fever.
A 64-year-old female with DM2 and HTN visiting from Kenya presented to the ER with history of 2 weeks of left eye ptosis, limited extraocular movements and blurry vision. She was initially suspected to have a diabetic partial cranial nerve III palsy. However, on examination, she was found to have left sided eye proptosis, ptosis, impairment of adduction and upward gaze without pupillary involvement, forehead muscle weakness and nasolabial flattening. No fever, cough, or meningeal signs were present. Over the course of 2-3 days, she developed numbness on the left side of the face, left pupillary dilation with decreased light reflex and near complete ophthalmoplegia. An LP revealed an opening pressure of 31 cm H2O with normal CSF analysis and microbial cultures. ACE in blood and CSF were negative. Brain MRI showed contrast enhancement of the left eye extraocular muscles, left lacrimal gland, and leptomeninges with nodular thickening on the lateral aspect of the left cavernous sinus and effacement of the oculomotor cistern. A lymph node biopsy demonstrated acid-fast bacilli identified by FITE stain and a positive culture for mycobacterium tuberculosis. The ocular motility and visual acuity improved significantly after the first month on treatment with prednisone and RIPE.
We report a rare case of CNS TB that presented as orbital apex syndrome with proptosis, secondary to elevated ICP and meningeal inflammation. A high index of suspicion is needed to improve outcomes.