Myelitis: A Common Complication of Tuberculous Meningitis Predicting Poor Outcome

Acute ischemic stroke in tuberculous meningitis

Background

The underlying mechanism for stroke in patients with tuberculous meningitis (TBM) remains unclear. This study aimed to investigate the predictors of acute ischemic stroke (AIS) in TBM and whether AIS mediates the relationship between inflammation markers and functional disability.

Methods

TBM patients admitted to five hospitals between January 2011 and December 2021 were consecutively observed. Generalized linear mixed model and subgroup analyses were performed to investigate predictors of AIS in patients with and without vascular risk factors (VAFs). Mediation analyses were performed to explore the potential causal chain in which AIS may mediate the relationship between neuroimaging markers of inflammation and 90-day functional outcomes.

Results

A total of 1,353 patients with TBM were included. The percentage rate of AIS within 30 days after admission was 20.4 (95% CI, 18.2-22.6). A multivariate analysis suggested that age ≥35 years (OR = 1.49; 95% CI, 1.06-2.09; P = 0.019), hypertension (OR = 3.56; 95% CI, 2.42-5.24; P < 0.001), diabetes (OR = 1.78; 95% CI, 1.11-2.86; P = 0.016), smoking (OR = 2.88; 95% CI, 1.68-4.95; P < 0.001), definite TBM (OR = 0.19; 95% CI, 0.06-0.42; P < 0.001), disease severity (OR = 2.11; 95% CI, 1.50-2.90; P = 0.056), meningeal enhancement (OR = 1.66; 95% CI, 1.19-2.31; P = 0.002), and hydrocephalus (OR = 2.98; 95% CI, 1.98-4.49; P < 0.001) were associated with AIS. Subgroup analyses indicated that disease severity (P for interaction = 0.003), tuberculoma (P for interaction = 0.008), and meningeal enhancement (P for interaction < 0.001) were significantly different in patients with and without VAFs. Mediation analyses revealed that the proportion of the association between neuroimaging markers of inflammation and functional disability mediated by AIS was 16.98% (95% CI, 7.82-35.12) for meningeal enhancement and 3.39% (95% CI, 1.22-6.91) for hydrocephalus.

Conclusion

Neuroimaging markers of inflammation were predictors of AIS in TBM patients. AIS mediates < 20% of the association between inflammation and the functional outcome at 90 days. More attention should be paid to clinical therapies targeting inflammation and hydrocephalus to directly improve functional outcomes.

Clinical Approach to Myelopathy Diagnosis

OBJECTIVE

This article describes an integrative strategy to evaluate patients with suspected myelopathy, provides advice on diagnostic approach, and outlines the framework for the etiologic diagnosis of myelopathies.

LATEST DEVELOPMENTS

Advances in diagnostic neuroimaging techniques of the spinal cord and improved understanding of the immune pathogenic mechanisms associated with spinal cord disorders have expanded the knowledge of inflammatory and noninflammatory myelopathies. The discovery of biomarkers of disease, such as anti-aquaporin 4 and anti-myelin oligodendrocyte glycoprotein antibodies involved in myelitis and other immune-related mechanisms, the emergence and identification of infectious disorders that target the spinal cord, and better recognition of myelopathies associated with vascular pathologies have expanded our knowledge about the broad clinical spectrum of myelopathies.

ESSENTIAL POINTS

Myelopathies include a group of inflammatory and noninflammatory disorders of the spinal cord that exhibit a wide variety of motor, sensory, gait, and sensory disturbances and produce major neurologic disability. Both inflammatory and noninflammatory myelopathies comprise a broad spectrum of pathophysiologic mechanisms and etiologic factors that lead to specific clinical features and presentations. Knowledge of the clinical variety of myelopathies and understanding of strategies for the precise diagnosis, identification of etiologic factors, and implementation of therapies can help improve outcomes.

Central Nervous System Tuberculosis in Immunocompromised Patients: A Case Report Emphasizing Immune Status and Early Recognition and Treatment

Tuberculosis (TB) remains a global health challenge. Although pulmonary TB is the most frequent presentation, extrapulmonary involvement can occur, especially in immunocompromised patients. HIV-positive individuals are particularly vulnerable to opportunistic infections, such as TB, and CNS involvement is more prevalent in these patients, often leading to a poorer prognosis. CNS TB management is challenging due to nonspecific symptoms and delayed diagnosis, contributing to high mortality. It can manifest diffusely as tuberculous meningitis (TBM), localized as tuberculoma or tuberculous abscess, or as extradural and intradural spinal infections. TBM is the primary CNS manifestation, bearing significant morbidity and mortality, and rarely complicates with involvement of the spinal cord, termed tuberculous myelitis, which is associated with an unfavorable prognosis. A 61-year-old male, smoker with a history of substance abuse, undergoing seven months of antiretroviral therapy (ART) for HIV-1, presented with a two-day history of altered consciousness, sphincter incontinence, and fever. He also reported headaches, dizziness, and sleep disturbances over the past months. The examination revealed fever, asthenia, prostration, disorientation, neck rigidity, and bilateral lower limb weakness. Initial tests indicated lymphopenia, hyponatremia, and a slightly elevated C-reactive protein. Cranial CT showed no abnormalities. Lumbar puncture yielded abnormal cerebrospinal fluid (CSF), xanthochromic, hyperproteinorrheic (2316 g/L), hypoglycorrhagic (24mg/dl), with pleocytosis predominantly of mononuclear cells (98%). Compared to the values prior to ART treatment, the patient had a decreased HIV-1 viral (44 copies/ml) load but also a decreased CD4+ cell count (43 cells/mm3). Given the patient's rapid clinical deterioration, immunosuppression history, and a positive interferon-gamma release assay (IGRA) prior to ART, treatment with antituberculous drugs and dexamethasone was started at admission. Subsequently, Mycobacterium tuberculosis was identified through polymerase chain reaction (PCR) of the CSF. Cranial and spinal MRI revealed leptomeningeal enhancement from C2-C3 to the cauda equina, consistent with meningitis, without intracranial extension, and findings suggestive of myelitis, without evidence of tuberculomas or spinal cord osseous involvement. One week after treatment, the recovery of higher neurological functions became evident. Improvement in lower limb motor deficits had a delayed trajectory, with marginal progress observed at discharge. After an eight-week incubation, CSF mycobacterial culture analysis yielded negative results. This case discusses the importance of early suspicion and intervention in CNS infection prognosis. Attention to signs and symptoms beyond the most frequent ones is crucial, particularly in immunocompromised individuals like HIV patients. Identifying CSF features in different CNS infections and group-specific particulars facilitates the prompt initiation of treatment. Additionally, in co-infected patients (HIV and CNS TB), considering factors such as ART duration, CD4+ cell count, and viral load is important, in influencing the disease's incidence, course, and prognosis.

Isolated Tuberculous Transverse Myelitis Without Meningitis Among Patients With AIDS: A Case Report

Acute transverse myelitis is an inflammatory disorder of the spinal cord, characterized by acute or subacute onset of paraparesis, bilateral sensory deficit, and impaired urinary bladder and sphincter tone function. Mycobacterium tuberculosis, a very rare cause of transverse myelitis, especially tuberculous myelitis without meningitis, is extremely rare. The main etiologic mechanism consists of an abnormal activation of the immune system against the spinal cord as well as the direct invasion by the bacillus. We present a 30-year-old Thai woman with AIDS, presenting with paraplegia for two days. Her MRI of the whole spine showed nodular enhancing intramedullary lesions involving the spinal cord at the T11-T12 level, and intramedullary enhancing lesion along the T12 spinal cord to the conus medullaris. Cerebrospinal fluid (CSF) examination revealed only a few white blood cells without hypoglycorrhachia or elevated CSF protein. CSF polymerase chain reaction (PCR) and culture for M. tuberculosis produced negative results. Other investigations did not demonstrate other organ involvement. Spinal cord biopsy at T12 was performed and exhibited diffuse epithelioid histiocytic proliferation admixed with small lymphocytes and plasma cells with numerous acid-fast bacilli (AFB)-positive bacilli organisms. PCR for M. tuberculosis was also detected in spinal cord tissue. Thus, acute transverse myelitis caused by isolated tuberculous myelitis without meningeal involvement was diagnosed. She had marked clinical improvement and neurologic recovery after treatment with anti-tuberculosis and intravenous steroid pulses. Isolated M. tuberculosis spinal tuberculous myelitis without meningitis is exceptionally uncommon and should be carefully considered, particularly in severely immunocompromised individuals residing in regions with a high tuberculosis burden.

Tuberculous myelitis: a prospective follow-up study

Background

Prospective studies regarding tuberculous myelitis are lacking. We aimed to prospectively evaluate patients with tuberculous myelitis to identify the features that distinguish tuberculous myelitis from other myelitis.

Methods

This was a prospective study. Patients presenting with paraparesis/quadriparesis, and MRI showing myelitis were included. All patients were subjected to clinical, neuroimaging, and laboratory evaluation. Diagnosis of definite tuberculous myelitis was made if GeneXpert test in CSF was positive. Probable tuberculous myelitis was diagnosed if there was evidence of tuberculosis elsewhere in the body. Patients were treated with methylprednisolone and antituberculosis treatment. Patients were followed for 6 months. We compared the clinical, laboratory, and neuroimaging parameters and response to treatment of tuberculous myelitis with other myelitis. P values were adjusted using the Benjamini-Hochberg (BH) procedure to control false discovery rate.

Results

We enrolled 52 patients. Eighteen (34.6%) patients had tuberculous myelitis. Headache (P = 0.018) was significantly more common in tuberculous myelitis. The CSF protein (P < 0.001), and CSF cell count (P < 0.001) were significantly higher in tuberculous myelitis. On neuroimaging, a LETM was common in tuberculous myelitis. Spinal meningeal enhancement (14; 77.8%), extra-axial collection, and CSF loculation (6; 33.4%), arachnoiditis (3;16.7%), and concomitant spinal tuberculoma (2;11.1%) were other common imaging features of tuberculous myelitis. Tuberculous myelitis patients showed a better response (P = 0.025) to treatment.

Conclusion

Tuberculous myelitis was seen in approximately 35% of all myelitis cases, in a high tuberculosis endemic zone. Headache, markedly elevated CSF protein and spinal meningeal enhancement were distinguishing features. Tuberculous myelitis patients responded well to corticosteroids.