Trading one disease for another: The transplantation dilemma

Something fishy about mercury! Despite its otherwise health-promoting nutritional profile, some concern has been expressed about fish as a potential source of mercury in children. This concern, however, has yet to be subjected to careful testing. In this issue of The Journal, Innis et al in British Columbia report an analysis of blood mercury levels, some indices of child behavior, and a plasma marker of fish intake. They found a disturbingly high level of mercury in the blood of many children, especially those of Chinese ethnicity. Some of these had behavioral features consistent with neurotoxicity. An accompanying editorial by Jacobson and Jacobson highlights an important feature of the Innis study. It appears that the major source of mercury in these Chinese children was not local (Vancouver) fish, but rather imported product. This points out the importance of examining specific groups of children (i.e. immigrants) whose risk for environmental exposures may exceed those of the population as a whole; the important observations of Innis et al could have been lost in a broader study of all Vancouver children.

—Thomas R. Welch, MD page 759 (article) page 716 (editorial)

Inflammation and RDS associated with IVH The epidemiology of intraventricular hemorrhage (IVH) in preterm infants has always been puzzling. IVH is most frequently detected in the first day of life. Although IVH may become more severe at later times, a new IVH is unusual after 2-3 days of life. This early occurrence has been associated with vaginal birth and low blood pressures soon after birth, and with increased severity of illness of the infant. Prenatal corticosteroids increase blood pressure, decrease RDS, and decrease IVH. RDS (lung immaturity) or its management cause the recruitment of inflammatory cells to the lungs, activation of clotting systems, and increased inflammatory mediators in the airspaces. Krediet et al report a correlation between RDS, increased levels of the pro-inflammatory mediators IL-6, IL-8, and the oxidant byproduct malondialdehyde in plasma within 12h of age and IVH detected within the first 24h of birth. There were no such correlations with IVH that occurred after 24h of age. The associations between systemic inflammation, RDS, and early IVH remain hypothesis-generating observations as to why IVH occurs.

Trading one disease for another: The transplantation dilemma Organ transplantation in children has become almost routine in many centers. With many of the technical complexities satisfactorily addressed, attention today is moving toward the complications of immunosuppression. Although modern drug regimens have made transplantation feasible, they also carry substantial morbidity. This is particularly concerning, since our current concept is that such immunosuppression needs to be continued forever. In this context, a report in this issue of The Journal by Starzl and his group, although preliminary, is of enormous interest. In a series of 17 children undergoing kidney transplantation at Children’s Hospital of Pittsburgh, a strategy of antibodyinduced lymphocyte depletion prior to transplantation was combined with a major reduction in the intensity of post-transplantation immunosuppression. Conceptually, the idea was to attenuate the immediate anti-donor lymphocyte response, as well as provide conditions that could permit microchimerism to take place. Although the follow-up of these children is still short, the results are remarkable. All but one are currently enjoying excellent graft function, on a very low dose immunosuppression protocol and receiving no corticosteroids. If this experience is continued and replicated, the implications for pediatric transplantation are almost revolutionary. —Thomas R. Welch, MD

page 813

—Alan H. Jobe, MD, PhD page 740

The Journal of Pediatrics

June 2006

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