Intracranial tuberculous abscess
The epidemiology of patients with tuberculous abscesses is essentially the same as that of other CNS manifestations of tuberculosis (see CNS tuberculosis), although they are more frequently encountered in patients who are immunocompromised 2.
Patients with tuberculous abscesses present non-specifically, with focal neurological deficits, seizures or sign and symptoms of raised intracranial pressure 1.
In contrast to tuberculomas, tuberculous abscesses are filled with pus and have distinct microscopic changes: vascular granulation tissue in the wall, absence of epithelioid granulomatous reaction (seen in tuberculoma) 1,3,4. Furthermore, Mycobacterium tuberculosis can be isolated from the pus, which is sometimes unable to be isolated from tuberculomas 1.
Tuberculous abscesses have appearances very similar, and often identical, to pyogenic cerebral abscesses. They tend to be solitary, but can be multiloculated, and are relatively large and faster growing, compared to tuberculomas, that are usually a little smaller 4. They are surrounded, as is the case with pyogenic abscesses, but abundant vasogenic oedema 1. Tuberculous meningitis may or may not co-exist 3.
Appearances are those of a cerebral abscess: a peripherally enhancing lesion with low attenuation centre surrounded by vasogenic oedema.
As is the case with CT, MRI appearances are those of a cerebral abscess 1-3.
- central low intensity (hyperintense to CSF)
- peripheral low intensity (vasogenic oedema)
- T1 C+ (Gad): ring enhancement
- central high intensity (hypointense to CSF, does not fully attenuate on FLAIR)
- peripheral high intensity (vasogenic oedema)
- the abscess capsule may be visible as a intermediate to slightly low signal thin rim
- high DWI signal is usually present centrally
Treatment and prognosis
Treatment is surgical drainage is often curative, with concurrent multi-agent antituberculous antibiotics.
- pyogenic cerebral abscess
- fungal cerebral abscess
- more often multiple
- less surrounding vasogenic oedema
- centre is T2 iso or hypo-intense (best clue) 1,3
- causative agent
- tuberculoma (tuberculous granuloma)
- tuberculous abscess
- miliary tuberculosis
- pulmonary tuberculosis
- cardiac tuberculosis
- intracranial tuberculosis
- tuberculous otomastoiditis
- gastrointestinal tuberculosis
- genitourinary tuberculosis
- skeletal tuberculosis
- tuberculous mastitis
- tuberculous lymphadenopathy
- tuberculous adrenalitis
- 1. Garg RK. Tuberculosis of the central nervous system. Postgrad Med J. 1999;75 (881): 133-40. doi:10.1136/pgmj.75.881.133 - Free text at pubmed - Pubmed citation
- 2. Prakash M, Johnny JC. Intra cranial complications of tuberculous otitis media. J Pharm Bioallied Sci. 2015;7 (5): S51-4. doi:10.4103/0975-7406.155795 - Free text at pubmed - Pubmed citation
- 3. Ripamonti D, Barbò R, Rizzi M et-al. New times for an old disease: intracranial mass lesions caused by Mycobacterium tuberculosis in 5 HIV-negative African immigrants. Clin. Infect. Dis. 2004;39 (5): e35-45. doi:10.1086/422876 - Pubmed citation
- 4. Chatterjee S. Brain tuberculomas, tubercular meningitis, and post-tubercular hydrocephalus in children. J Pediatr Neurosci. 2011;6 (3): S96-S100. doi:10.4103/1817-1745.85725 - Free text at pubmed - Pubmed citation