Opportunistic infections in children following renal transplantation.

Opportunistic infections following renal transplantation in children are a major cause of severe morbidity and mortality. These infections account for the majority of early post renal-transplant deaths in children. General risk factors which affect the incidence and severity of these infections include: transmission of the infectious agent by the donor organ; history of immunity in the recipient prior to transplantation; type and amount of immunosuppression including treatment for rejection episodes; availability of specific treatment for the infection. Children are at particular risk because of the lack of exposure to certain pathogens prior to transplantation. There have been recent advances in the prevention and treatment of important infections which occur in children following transplantation, including varicella, Pneumocystis carinii pneumonia (PCP) and cytomegalovirus (CMV) disease. Varicella is treatable with acyclovir, often without decreasing immunosuppression and placing the graft at risk. Prophylaxis against PCP may be achieved by provision of alternate-day trimethoprim sulpha, but clear guidelines for determining who should be treated are lacking. Treatment of this disease with high-dose trimethoprim sulfa or pentamidine is usually successful. CMV disease is frequently severe, especially when the donor is seropositive and the recipient seronegative. In these situations, prophylactic CMV immunoglobulin reduces the morbidity and the mortality of the disease and prophylactic oral acyclovir may decrease its incidence. Treatment of severe CMV disease with gancyclovir is promising.