Optochiasmatic tuberculomas: A vision-threatening paradoxical response in tuberculous meningitis

Abstract

The single main cause of death from infectious diseases worldwide is tuberculosis, which is more prevalent in developing countries. Tuberculous meningitis (TBM) is a severe form of TB in which morbidity and mortality depend upon the stage of presentation. Intracranial brain parenchymal tuberculomas may form paradoxically, days to months after starting antituberculous drug therapy. Tuberculomas may develop in and around he optic chiasm and optic nerves after institution of antituberculous treatment as a quite rare occurrence in TBM; this may lead to severe visual loss if not treated properly. We describe a 56-year-old man with documented TBM being treated with first line antituberculous drugs who developed visual impairment 2 months after starting the treatment. MRI after gadolinium administration revealed multiple perichiasmatic and a few parenchymal ring enhancing lesions due to tuberculomas. The patient was treated with corticosteroids and antituberculous therapy was continued after which he recovered his vision gradually. Visual impairment developing in a patient on treatment with antituberculous drugs should give rise to a suspicion of rare optochiasmatic tuberculomas; this necessitates urgent contrast-enhanced MRI of the brain and prompt treatment with steroids.