Why has the incidence of tuberculosis increased?
The incidence of tuberculosis has increased as a consequence of HIV infection and the use of immunosuppressive drugs.
Which organs do tuberculosis most commonly involve?
Tuberculosis involves most frequently the lungs. However, this infection may affect any organ and systems – central nervous, musculoskeletal, cardiac, respiratory, gastrointestinal, and genitourinary systems, particularly in immunocompromised patients.
Which are the main differences between tuberculosis in immunocompromised patients and the general population?
Immunocompromised patients are more affected by tuberculosis than the general population. In addition, it is necessary to be aware of multidrug-resistant (MDR) TB and the extrapulmonary features of tuberculosis in immunocompromised patients.
What are the characteristics of pulmonary miliary tuberculosis?
Pulmonary miliary tuberculosis results from the hematogenous spread of Mycobacterium tuberculosis bacilli and usually occurs with multiorgan involvement. It is more frequently in the elderly, infants, and immunocompromised persons, manifesting within six months of initial exposure. The classic radiographic and CT findings are diffuse small 2-3 mm nodules in both lungs. CT is very sensitive and shows the nodules in a random distribution. The nodules usually resolve within 2 – 6 months with treatment, without scarring or calcification.
What are the characteristics of CNS tuberculosis?
CNS tuberculosis may result from direct rupture or extension of a subependymal or subpial focus (Rich focus) or the hematogeneous spread. The disease may manifest in various forms, including tuberculous meningitis, tuberculomas, tuberculous abscess, tuberculosis cerebritis, and miliary tuberculosis, which may occur in combination.
Which are the MRI characteristics of brain tuberculomas?
The characteristics depend on whether tuberculoma is noncaseating or caseating. Usually, there is a progression from noncaseating to caseating lesions. A noncaseating tuberculoma has signal hypointensity relative to gray matter on T1WI and hyperintensity on T2WI, with homogeneous contrast enhancement. A caseating tuberculoma may have a solid or a liquid center. Tuberculoma with a solid center is isointense to hypointense on both T1WI and T2WI, with perifocal edema. Caseating tuberculomas with a liquid center are hypointense on T1WI and centrally hyperintense with a peripheral hypointense rim on T2WI, with rim enhancement and surrounding edema.
Follow-up contrast-enhanced cranial MRI reveals a significant decrease in the abscess/caseating tuberculomas, presenting as numerous bilateral lesions with a ring or nodular enhancement in the cerebral and cerebellar hemispheres and marked amelioration of surrounding edema. The two larger lesions in the right middle temporal gyrus and the ipsilateral paracentral lobe demonstrate restricted diffusion and annular enhancement, representing caseating tuberculomas with central liquefaction/tuberculous abscess. There are still several small foci of marked SWI hypointense signal related to calcification or bleeding.
Impression
Multiple brain lesions related to CNS tuberculosis - tuberculomas/abscesses.