Optic pathways tuberculoma mimicking glioma: case report

Optic nerve tuberculoma in an immunocompetent patient: Case report

Optic nerve tuberculoma is a rare extra-pulmonary manifestation of mycobacterial infection. It is usually associated with HIV infected patients. Due to its clinical polymorphism, the diagnosis and management of the disease either in immunocompetent patients and immunocompromised ones remains challenging. Herein, we discuss a case of a 32-year-old patient with no history of immunodeficiency admitted for multifocal tuberculosis with a reduced visual acuity as an extra-pulmonary manifestation, and radiologically revealed the presence of tuberculoma in the optic nerve in the cerebral MRI.

Orbital and external ocular manifestations of Mycobacterium tuberculosis: A review of the literature

Tuberculosis (TB) is an airborne infectious disease caused by Mycobacterium tuberculosis that most commonly affects the lungs. However, extrapulmonary manifestations of TB can affect the eye and surrounding orbital tissues. TB can affect nearly any tissue in the eye, and a high index of suspicion is required for accurate diagnosis. Systemic anti-tuberculosis treatment is required in cases of ocular TB, and steroids are sometimes necessary to prevent tissue damage secondary to inflammation. Delays in diagnosis are common and can result in morbidities such as loss of an affected eye. It is important for ophthalmologists and infectious disease specialists to work together to accurately diagnose and treat ocular TB in order to prevent vision loss. This article reports the various known presentations of orbital and external ocular TB and reviews important elements of diagnosis and treatment.

Paradoxical Growth of Optochiasmatic Tuberculoma during the Treatment of Tuberculous Meningitis

Intracranial brain parenchymal tuberculomas may form paradoxically, days to months after starting antituberculous drug therapy. They may develop in and around optic chiasm and optic nerves after antituberculous treatment as a quite rare occurrence in tuberculous meningitis (TBM) this may lead to severe visual loss if not treated properly. We describe a 5 year-old child with documented TBM being treated with first line antituberculous drugs which developed visual impairment 3 months after starting the treatment. MRI after gadolinium administration revealed multiple perichiasmatic ring enhancing lesions due to tuberculomas. 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.

Radiological evolution and delayed resolution of an optic nerve tuberculoma: Challenges in diagnosis and treatment

Optic nerve tuberculomas are rarely reported and their natural history, prognosis, and duration of required treatment remain unclear. A 40-year-old immunocompetent male presented with complete loss of vision in his right eye, which had evolved over 6 weeks. He had optic atrophy on examination. Initial imaging showed right optic nerve swelling and thickening suggesting an infiltrative inflammatory optic neuropathy (infectious or noninfectious). Serial imaging revealed appearance of ring enhancement with a necrotic centre. Biopsy and culture of the coexistent parietal lobe lesion revealed Mycobacterium tuberculosis. Persistent optic nerve granuloma with evidence of radiological improvement was noted at 18 months follow-up with antituberculous therapy (ATT). Visual recovery could not be achieved. The salient features in this case include the clinical presentation initially mimicking an infiltrative or compressive optic neuropathy, rapidradiological evolution into a tuberculoma, subtle paradoxical radiological worsening after initiation of ATT and persistence of granuloma on follow up scan. The challenges involved in early diagnosis and during the treatment course will be discussed.

Tuberculous optochiasmatic arachnoiditis: a devastating form of tuberculous meningitis

Tuberculous meningitis is primarily a disease of the meninges of brain and spinal cord along with adjacent brain parenchyma. The characteristic pathological changes are meningeal inflammation, basal exudates, vasculitis and hydrocephalus. Tuberculous meningitis has a strong predilection for basal parts of the brain. Exudates, if dominantly present in the interpeduncular, suprasellar and Sylvian cisterns, result in optochiasmatic arachnoiditis and tuberculoma. Optochiasmatic arachnoiditis and tuberculoma are devastating forms of tuberculous meningitis and often associated with profound vision loss. This clinical entity more frequently affects young adults. In a recent study, on the multivariate logistic regression analysis, female sex, younger age and raised cerebrospinal fluid protein content were identified as predictors for developing optochiasmatic arachnoiditis. Frequently, optochiasmatic tuberculoma and optochiasmatic arachnoiditis develop paradoxically while a patient is being treated with anti-TB drugs. MRI reveals confluent enhancing lesions that are present in the interpeduncular fossa, pontine cistern, and the perimesencephalic and suprasellar cisterns. Management of tuberculous optochiasmatic arachnoiditis and optochiasmatic arachnoiditis tuberculoma has been variable. Treatment of optochiasmatic arachnoiditis continues to be a challenge and the response is generally unsatisfactory. In isolated case reports and in small series, corticosteroids, methyl prednisolone, thalidomide and hyaluronidase have been used with variable success. The benefit from neurosurgery is controversial and deterioration may follow the initial temporary improvement. Management of paradoxical optochiasmatic arachnoiditis is also controversial. Some patients regain vision following treatment with anti-TB drugs and continued usage of corticosteroids. Neurosurgery may be considered in the patients with either treatment failure or when diagnosis is in doubt. In conclusion, presence of optochiasmatic arachnoiditis or tuberculoma has important therapeutic and prognostic implications for patients of tuberculous meningitis.

Orbital tuberculosis: a review of the literature

PURPOSE

To provide an up-to-date review of the clinical presentations, investigations, and management of orbital tuberculosis (OTB).

METHODS

Systematic review of the literature concerning OTB, limiting the results to English-language peer-reviewed journals.

RESULTS

Seventy-nine patients from 39 publications were identified as cases of OTB. The condition presents in one of five forms: classical periostitis; orbital soft tissue tuberculoma or cold abscess, with no bony involvement; OTB with bony involvement; spread from the paranasal sinuses; and tuberculous dacryoadenitis. The ocular adnexa, including the nasolacrimal system and overlying skin, may also be involved.

CONCLUSIONS

Diagnosis can be difficult and may necessitate an orbital biopsy, in which acid-fast bacilli (AFB) and characteristic histopathology may be seen. Growth of Mycobacterium tuberculosis (mTB) from such a specimen remains the gold standard for diagnosis. Ancillary investigations include tuberculin skin tests and chest radiography, but more recently alternatives such as whole blood interferon-gamma immunological tests and PCR-based tests of pathological specimens have proven useful. The management of OTB is complex, requiring a stringent public health strategy and high levels of patient adherence, combined with long courses of multiple anti-tuberculous medications. The interaction of the human immunodeficiency virus (HIV) with TB may further complicate management.

The optic nerve: radiologic, clinical, and pathologic evaluation

The radiologic investigation of the optic nerve plays an integral part in the diagnostic evaluation of diverse lesions of the optic pathways including inflammatory diseases, vascular disorders and benign and malignant tumors and these radiologic modalities consist principally of CT and MR imaging and, in vascular lesions, MR angiography and conventional angiography. The selection of radiologic studies and their focus is based on the ophthalmologic examination where the ophthalmologist can often determine the suspected location of lesions in the anterior or posterior visual pathways. Furthermore, inspection of the eye, including adnexal structures and funduscopy, provides additional information in the clinical assessment of these patients. With technical advances in the last few years, CT and MR imaging can detect lesions and determine their location and extent with high sensitivity and specificity. This article discusses the radiologic, clinical, and pathologic evaluation of the optic nerve.