This study aims to evaluate the risk of hepatitis B or tuberculosis reactivation in neuromyelitis optica spectrum disorder (NMOSD) patients with potential occult hepatitis B virus (HBV) infection (pOBI) or latent tuberculosis infection (LTBI) undergoing B-cell depletion therapy, providing evidence for clinical decision-making.

Currently, there are no established guidelines regarding the necessity of prophylactic anti-HBV or antituberculosis treatment for NMOSD patients with pOBI or LTBI undergoing B-cell depletion therapy. Data on the risk of hepatitis B or tuberculosis reactivation in these patients is limited.

We selected 102 NMOSD patients treated with inebilizumab or rituximab between January 1, 2016, and August 31, 2024. Liver function tests, HBV serology tests, and interferon-gamma release assay (IGRA) were performed to identify pOBI or LTBI. For pOBI patients, liver function, HBV serology, and HBV-DNA were continuously monitored to ascertain hepatitis B reactivation. For LTBI patients, IGRA was tested during subsequent treatments, and clinical and radiographic manifestations were used to assess tuberculosis reactivation. 

Among the 102 NMOSD patients, 40 (39.2%) patients had pOBI. After consultation with infectious disease specialists and considering patient preferences, 11 pOBI patients received prophylactic anti-HBV therapy. The remaining pOBI patients were continuously monitored for HBV serology, HBV-DNA, and liver function. During a median follow-up of 12 months (6.25-25 months), all patients tested negative for HBV-DNA, and no cases of active hepatitis occurred. Similarly, 9 (8.8%) patients with LTBI did not received prophylactic antituberculosis treatment. During a median follow-up of 11 months (7-17 months), no evidence of active tuberculosis was found. 

The risk of hepatitis B or tuberculosis reactivation appears to be low in NMOSD patients with pOBI or LTBI undergoing B-cell depletion therapy, even without prophylactic treatment. Regular monitoring and timely initiation of targeted treatment upon evidence of reactivation may be a more reasonable strategy.