Miliary Brain Tuberculomas and Meningitis: Tuberculosis Beyond the Lungs

Abstract

Tuberculosis remains one of the most common infectious diseases. Miliary presentation is a rare and possibly lethal form, resulting from massive lymphohaematogenous dissemination of Mycobacterium tuberculosis bacilli. The authors describe the case of a 47-year-old immunocompetent woman, diagnosed with miliary tuberculosis, with both lung and central nervous system involvement, who showed total recovery after starting anti-tuberculous drugs. The atypical neutrophilic-predominant pleocytosis and negative cerebrospinal fluid microbiological results made the diagnosis even more challenging. Since prognosis largely depends on timely treatment, recognition and prompt diagnosis is important. Thus, clinicians should be aware and treatment should be initiated as soon as the diagnosis is suspected.

Learning points: Cerebrospinal fluid (CSF) characteristics in central nervous system tuberculosis (CNS TB) are variable and may even be normal. Typical CSF findings include lymphocytic-predominant pleocytosis, although neutrophilic predominance may occur. CSF microbiological testing for Mycobacterium tuberculosis has low sensitivity, so a negative test does not eliminate the diagnosis.Cerebral magnetic resonance imaging is usually the test of choice, given its superiority in CNS TB diagnosis over computed tomography (CT), which can be normal.Chest x-ray may appear normal and miss miliary TB, which however a CT scan can identify.

Keywords: Miliary tuberculosis; brain tuberculomas; meningitis.

Figure 1

Cerebral magnetic resonance imaging demonstrating contrast enhanced small intra-axial lesions in the supratentorial and infratentorial compartments with a miliary pattern (-->), and leptomeningeal enhancement of basal cisterns, extending to the opercular region on the right (*).

Figure 2

Chest x-ray without obvious alterations.

Figure 3

Thoracoabdominopelvic computed tomography scan showing multiple millimetric pulmonary micronodules.