Paradoxical Reactions of Central Nervous System Tuberculosis: Report of Three Immunocompetent Cases.

Paradoxical reactions during tuberculosis (TBC) therapy are characterized by clinical or radiological worsening of preexisting tuberculous lesions or the appearance of new manifestations following appropriate TBC treatment. Identifying this phenomenon is crucial, since it can be mistaken with treatment failure or relapse. Although widely described in HIV patients following immune reconstitution inflammatory syndrome, the literature on HIV-negative patients is scarce. We present three cases of immunocompetent patients with central nervous system tuberculosis (CNS-TBC) who developed paradoxical reactions following appropriate TBC therapy. These included diverse clinical and radiological manifestations, such as persistent headaches, apparition or progression of tuberculomas, cerebral infarcts, and dorsal myelitis. Paradoxical reactions occurred within an average of 2.5 months from the start of anti-TBC treatment. Our findings underscore the importance of closely monitoring patients following anti-TBC treatment to identify potential complications rapidly. Paradoxical reactions due to exaggerated immune response to complex antigens should be considered in a thorough differential diagnosis including other CNS infections, granulomatous or neoplastic disorders, treatment failure, or treatment-related toxicities. Ensuring adequate adherence to anti-TBC treatment and immunosuppressants is essential in such cases.