The recurrence of focal segmental glomerulosclerosis (FSGS) in transplants is a well-known problem in pediatric renal transplantation (Tx). Recently, the race of the recipient was recognized as a major variable associated with disease recurrence. In view of this finding, we report on our single-center experience of FSGS recurrence in Korean children, an ethnically homogeneous Far East Asian population. Clinical records and renal biopsy specimens, both native and graft, were reviewed for all pediatric renal Txs (recipient age < or = 18 yr) performed at Seoul National University Hospital from 1984 to 1999. Twenty-two children with primary FSGS received 22 allografts for renal replacement. The mean age of disease onset in these patients was 5.9 yr. The grafts were from 12 living-related, six living-unrelated, and four cadaveric donors, and all recipients were immunosuppressed with cyclosporin A (CsA)-based regimens. Post-transplant recurrence of FSGS was confirmed in nine patients (41%). Long-term graft survival in recurrent and non-recurrent groups was not significantly different. Risk factor analysis showed that patients with a disease duration shorter than 48 months (odds ratio 11.7, 95% CI 1.53-89.1) and a glomerulosclerosis percentage of < 55% by renal biopsy (odds ratio 16.0, 95% CI 1.45-176) were at greater risk of disease recurrence. These results suggest that Korean children are similar to non-African-American youngsters in the USA and Europe with respect to post-transplant recurrence of FSGS. The same may be true of other Far Eastern Asian children.