Contribution of brain imaging to the diagnosis of intracranial tuberculoma and other brain lesions in patients presenting with miliary tuberculosis

The etiological spectrum of miliary brain lesions: A systematic review of published cases and case series

OBJECTIVE

This systematic review aimed to evaluate the published cases with miliary brain lesions and their etiological factors, clinical manifestations, diagnostic procedures, and outcomes.

METHODS

A comprehensive search of PubMed, Scopus, Embase, and Google Scholar was conducted using the specified search strategy. Eligibility criteria included cases with miliary lesions in the brain confirmed through neuroimaging and various diagnostic procedures. The PRISMA guidelines were followed, and the PROSPERO registration number for the protocol is CRD42023445849.

RESULTS

Data from 130 records provided details of 140 patients. Tuberculosis was the primary cause in 93 cases (66.4%), malignancies in 36 cases (25.7%), and other causes accounted for the remaining 11% cases. Tuberculosis patients averaged 35.7 years old, while those with malignancies averaged 55.44 years. Tuberculosis symptoms primarily included fever, headache, and altered sensorium, whereas malignant cases often exhibited progressive encephalopathy, headache, and specific neurological deficits. Distinctive indicators for CNS tuberculosis were choroidal tubercles and paradoxical reactions. Additionally, 63 tuberculosis patients showed miliary lung shadows and 49 had abnormal CSF findings. For the malignancy group, 13 exhibited miliary lung lesions, and 8 had CSF abnormalities. Regarding outcomes, a significant mortality disparity was observed, with 58.3% in the malignancy group, compared to 10.8% in the tuberculosis group and 27.3% in other cases.

CONCLUSION

Miliary brain lesions are a crucial imaging abnormality that necessitates prompt work up. In an immunocompromised state, diagnostic possibilities of miliary brain lesions are more varied and often pose a bigger challenge.

Miliary meningeal tuberculosis - an unusual imaging presentation for an early definitive diagnosis

PURPOSE

Tuberculous meningitis (TBM) causes significant morbidity and mortality in young children. Early treatment can be initiated with magnetic resonance (MR) imaging diagnosis. We present MR-detectable miliary meningeal TB in two patients. CASE 1: A 9-year-old girl developed fevers, cough, lethargy, and seizures. Brain MRI demonstrated multiple, small, T2-dark, rim-enhancing lesions, associated with cranial nerve and leptomeningeal enhancement. CSF showed pleocytosis, low glucose, and high protein. Chest CT showed mediastinal lymphadenopathy, multiple small interstitial lung nodules, and a splenic hypo enhancing lesion. Serial bronchoalveolar lavage studies were Xpert MTB/RIF and acid-fast negative. Endobronchial US-guided biopsy of a subcarinal lymph node was positive for Xpert MTB PCR. She was started on a 4-drug treatment for TBM and dexamethasone. Contact tracing revealed a remote positive contact with pulmonary tuberculosis. CASE 2: A 17-year-old female with Crohn's disease on adalimumab developed refractory ear infections despite multiple courses of antibiotics. She underwent myringotomy, with negative aerobic ear fluid culture. Brain MRI, obtained due to persistent otorrhea, showed multiple, small, round, T2-dark lesions. CSF studies were normal. CT chest, abdomen, and pelvis to assess for disseminated disease showed left upper lobe tree-in-bud nodules, hypoattenuating splenic lesions and a left obturator internus abscess with adjacent osteomyelitis. She underwent CT-guided aspiration of the obturator muscle collection, bronchoscopy with bronchoalveolar lavage, biopsy of two preexisting chronic skin lesions, and ear fluid aspiration. QuantiFERON Gold was positive. Ear fluid was Xpert MTB/RIF assay and acid-fast stain positive. Cultures from the ear fluid, skin tissue, muscle tissue, and alveolar lavage showed growth of acid-fast bacilli. She was started on 4-drug therapy and prednisone.

CONCLUSION

Our cases highlight that TBM in many cases remains a diagnostic dilemma - both our patients presented in a prolonged atypical manner. The term miliary TB not only refers to a pattern of interstitial nodules on chest radiographs but also indicates the hematogenous spread of the disease and concurrent pulmonary and extrapulmonary involvement with high risk of TB meningitis. We promote the use of the term miliary meningeal TB - in both cases, the neuroimaging diagnosis of TB preceded both chest imaging and laboratory confirmation of the disease. Miliary meningeal nodules on MRI may have characteristic T2 low signal and may be more conspicuous in children and immunocompromised individuals where background basal meningeal enhancement is less prominent.

Extremely high levels of central nervous system involvement in miliary tuberculosis

Background

Miliary tuberculosis (TB) is one of the severest manifestations of TB that can be lethal when concomitant with the central nervous system (CNS) involvement. Bacteriological, biochemical and radiological methods for find CNS comorbidity in miliary TB was evaluated in this study.

Methods

Consecutive miliary TB adults were retrospectively enrolled from two designated TB hospitals in China. The capacities of examinations of cerebrospinal fluid (CSF), cerebral computed tomography (CT) and magnetic resonance imaging (MRI) for diagnosis of CNS involvement were assessed.

Results

Assessment of CNS involvement with a lumbar puncture and/or neuroimaging was undertaken in 282 out of 392 of acute miliary TB. Of these 282 patients, 87.59% (247/282) had CNS involvement. Cerebral contrast-enhanced MRI (96.05%, 170/177) and MRI (93.15%, 204/219) yielded significantly higher sensitivities over CSF examination (71.92%, 146/203, P < 0.001) and CT (34.69%, 17/49, P < 0.001). The sensitivity of CSF examination was superior to CT scan (P < 0.001). Although 59.65% (134/225) miliary TB patients acquired bacteriological evidence with sputum examination, the positivity was only 8.82% (21/238) for CSF examination by conventional and molecular tests.

Conclusion

Almost all miliary TB had CNS involvement and MRI demonstrated outstanding potential over other methods. Therefore, a routinely screening of CNS TB should be strongly suggested in miliary TB and MRI could be used as the initial approach in resources rich settings.

Relationship between magnetic resonance imaging findings and prognosis of intracranial tuberculosis

BACKGROUND

Intracranial tuberculosis (TB) is an intracranial infection caused by Mycobacterium tuberculosis. Magnetic resonance imaging (MRI), in particular enhanced MRI scan, has the ability to detect characteristic lesions of tuberculous meningitis or cerebral parenchymal TB.

PURPOSE

To analyze the relationship between MRI findings and prognosis of patients with intracranial TB.

MATERIAL AND METHODS

In this retrospective study, a total of 60 patients were confirmed with intracranial TB in the hospital from May 2019 to December 2020. All enrolled patients underwent TB-related laboratory examinations, cranial MRI, and contrast-enhanced MRI. Laboratory tests were analyzed and the relationship between clinical prognosis and cranial MRI features was evaluated.

RESULTS

Of the 60 patients, 28 (46.67%) had disseminated TB complications, 20 (36.67%) had secondary TB complications, and the remaining 10 (16.66%) had lymphatic TB or spinal TB complications. Of the patients, 25 had good short-term prognosis and 35 had poor short-term prognosis; 44 patients had good long-term prognosis and 16 had poor long-term prognosis. The incidence of cerebral parenchymal tuberculomas on enhanced MRI was significantly higher in the group with good prognosis compared to that in the group with poor prognosis (P < 0.05). Logistic analysis suggested that hydrocephalus (odds ratio [OR] = 0.057, 95% confidence interval [CI] = 0.003-0.444; P = 0.018) and cistern involvement (OR = 0.100, 95% CI = 0.011-0.581; P = 0.017) were independent risk factors for poor short-term prognosis.

CONCLUSION

MRI can display the pathological changes of intracranial TB in detail; hydrocephalus and cistern involvement were independent risk factors for poor short-term prognosis.