TNF and interstitial lung disease: A study based on the FDA Adverse Event Reporting System database indicated that rituximab is among the drugs most commonly associated with ILD.[4] The mechanism of rituximab-induced ILD remains unclear, but may be related to complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, and increased expression of cytokines such as TNF-α,[5,6] interleukin-6 (IL-6),[7] and interleukin-1β (IL-1β).[8] In this case, serum TNF-α levels were routinely monitored prior to rituximab administration.