In this PACULit episode, a Western China retrospective study evaluates the real-world effectiveness of eculizumab for atypical hemolytic uremic syndrome (aHUS). The cohort (n=17) examines early versus delayed initiation (within 7 days of symptom onset) and reports substantial renal and hematologic responses with early treatment, including marked improvements in serum creatinine, eGFR, platelets, and LDH, along with reduced dialysis dependency. Early initiators showed higher renal and hematologic remission rates and better short-to-mid-term renal survival compared with delayed initiators. The discussion covers safety considerations, infection risk management, and the need for meningococcal vaccination and vigilance for non-meningococcal infections, as well as implications for practice in resource-limited settings. Limitations include small sample size and retrospective design. The findings align with guidelines supporting early complement blockade and highlight the role of multidisciplinary care and genetic testing in tailoring therapy, with notes on cost-effectiveness and future directions such as longer-acting agents and broader real-world data.