Myelitis: A Common Complication of Tuberculous Meningitis Predicting Poor Outcome

Abstract

BackgroundMyelitis is an important complication in patients with tuberculous meningitis (TBM). However, a paucity of publications exists on the spectrum of neurological and MRI findings of TBM-related myelitis. The risk factors and prognosis of myelitis in patients with TBM are not fully understood. Therefore, this study aims to identify the risk factors, clinicoradiological features, and prognostic impact of myelitis for patients with TBM.MethodsWe conducted a retrospective study in our institution. Patients with TBM who were consecutively admitted during the period of August 2015 to December 2019 were included. We reviewed the demographic characteristics, clinical, laboratory and MRI findings, and clinical outcomes of all of the included patients. The diagnosis of myelitis was identified by a hyperintensity on T2-weighted images that were associated with cord edema, enlargement, and marginal or no enhancement on contrast-enhanced images.ResultsA total of 114 patients were included. Myelitis occurred in 19 (16.7%) patients, five of whom paradoxically developed myelitis. The common clinical signs of myelitis were paraparesis (738.9%), quadriparesis (844.4%), urinary retention or constipation (1,477.8%), and paresthesias in the lower limbs (1,052.6%). In the MRI findings, the hyperintensities on T2-weighted images involved more than 3 spinal cord segments. Myelitis was often combined with other forms of spinal cord injury, including 10 patients (52.6%) with spinal meningeal enhancement, 7 patients (36.8%) with enlargement of the central canal of the spinal cord, 6 patients (31.6%) with tuberculoma, and 4 patients (21.1%) with arachnoiditis and 1 patient (5.3%) with cerebrospinal fluid (CSF) loculations. None of the 5 patients with paradoxical myelitis were complicated with spinal meningeal enhancement and arachnoiditis, while 4 patients were complicated with enlargements of the central canal of the spinal cord. In multivariable analysis, a grade III disease severity on admission [p = 0.003, odds ratio (OR) = 8.131, 95% CI: 2.080–31.779] and high CSF protein (p = 0.033, OR = 1.698, 95% CI: 1.043–2.763) were independent risk factors for myelitis. After the 6 months follow-up, myelitis (p = 0.030, OR = 13.297, 95% CI: 1.283–137.812) and disturbance of consciousness (p = 0.042, OR = 12.625, 95% CI: 1.092–145.903) were independent risk factors for poor outcomes.ConclusionMyelitis was a common complication of TBM and independently predicted a poor outcome. A grade III disease severity and high CSF protein on admission were independent risk factors for myelitis. Paradoxical myelitis was rarely complicated with spinal meningeal enhancements and arachnoiditis, indicating that the immune reaction may play a dominant role.

Tuberculous myelitis: a prospective follow-up study

“…We found that the cervico-dorsal spinal cord was the most commonly involved area in cases of tuberculous myelitis. The findings of cervico-dorsal LETM as a common imaging manifestation of tuberculous myelitis are consistent with other recent studies [24]. Other neuroimaging findings were the presence of spinal meningeal enhancement, CSF loculation, tuberculoma, extra-axial collection, and arachnoiditis.…”

“…These findings suggest that tuberculous myelitis may not be an isolated entity; rather, it can be a combination of meningo-myelitis. A similar combination of neuroimaging findings has also been described in other studies [24].…”

“…These inflammatory reactions may also lead to myelitis. Previous studies have also reported paradoxical tuberculous myelitis occurring during the treatment of tuberculous meningitis [23,24]. Previous studies have also shown an association between the occurrence of pulmonary tuberculosis and inflammatory demyelination of the spinal cord and suggested underlying immune mechanisms as the cause of myelitis [25].…”

Tuberculous meningomyelitis: Report of a case

“…Early evidence for TB-M includes lymphocytic pleocytosis and normal or low glucose levels on CSF and a positive IGRA test [4]. Central nervous system infarctions, communicating hydrocephalus and basal meningeal, and spinal cord enhancement on post-contrast are common findings in MRI [3,[5][6][7].…”

Clinical Approach to Myelopathy Diagnosis

“…Inflammatory myelopathies constitute the most frequently occurring myelopathies and have diverse immune-mediated disease mechanisms associated with them. With a better understanding of the immune process and the discovery of new disease biomarkers, the diagnostic spectrum of this group of myelopathies continues to expand ( table 1-4 52-59 and table 1-5 60-67 ). The mechanisms of immune-mediated disease include demyelinating disease associated with multiple sclerosis, autoimmune myelopathies associated with specific antibodies against neural antigens (eg, NMO, MOG-associated disorders, paraneoplastic disorders), autoimmune myelopathies related to systemic autoimmune or rheumatologic diseases (eg, Sjögren syndrome, systemic lupus erythematous), infection-associated myelopathies, and other inflammatory myelopathies caused by the use of medications that target immune pathways that trigger autoimmune responses against the spinal cord such as immune checkpoint inhibitors used in cancer treatment 68 or tumor necrosis factor inhibitors in the treatment of rheumatologic disorders 69 …”