Aim To investigate the efficacy and safety of cyclophosphamide and other immunosuppressive agents (ISAs) in the treatment of necrotising scleritis.

Methods We reviewed the medical records of patients with necrotising scleritis at 11 tertiary care centres in South Korea from 2002 to 2012, treated with ISAs within 3 months of follow-up period. We divided patients into two groups: a group treated with cyclophosphamide (CYC group) and a group treated with other ISAs; azathioprine, ciclosporin, methotrexate and mycophenolate mofetil (OISA group). Main outcome measures evaluated were remission rate, relapse rate, rate of visual loss, steroid-sparing rate, adverse effects and discontinuation of medication due to adverse effects.

Results CYC group had a remission in 95.2% of the patients and OISA group had in 96.3%. Remission rate, relapse rate, visual loss rate and steroid-sparing rate were not significantly different between the two groups (all p>0.05). The median duration of steroid use was longer in CYC group than in other OISA group (55 vs 16 days, p=0.09). The incidence of adverse effects in the CYC group was comparable with that of the OISA group (61.9% vs 41.4%, p=0.15). However, the incidence of leucopenia, haemorrhagic cystitis and discontinuation of medication due to adverse effects were much higher in the CYC group (p<0.001, p<0.001, p=0.05, respectively).

Conclusion The efficacy of cyclophosphamide in the treatment of necrotising scleritis was comparable with that of other ISAs. However, the rate of discontinuation due to side effects was much higher in the CYC group.