RecruitingPhase 4Drug trialZanubrutinib Combined With Rituximab in the Treatment of Secondary HLH in B-cell LymphomaFor patients who met the inclusion criteria, treatment regimens were administered: Rituximab 375 mg/m², intravenously, once weekly for 4 weeks. Zanubrutinib 160 mg, orally, twice daily for 4 weeks. Combined drugs: prednisone 100 mg/m²/d, orally, d1-5; Ruxolitinib 15mg bid orally; With/without emapalumab as appropriate.