Chronic peritoneal dialysis (CPD) is a common form of renal replacement therapy in children. Recent studies suggest that immunological abnormalities, in particular hypogammaglobulinemia, may develop in children and infants on peritoneal dialysis. We report an infant maintained on CPD who died of gram-negative sepsis. At post-mortem examination, he was noted to have severe panhypogammaglobulinemia.