Anesthesia in children with mastocytosis--a case based review.

Introduction: Mastocytosis is a rare heterogeneous disease of bone marrow origin which arises as a consequence of abnormal growth and/or accumulation of clonal mast cells in one or more organs. Sixty-five percent of patients with mastocytosis are children in whom it usually regresses around puberty. Adult patients with mastocytosis have been identified as at high risk of widespread mast cell degranulation in the perioperative period, this finding has not been reported in pediatric patients. This information has been repeated in mastocytosis websites where it has the potential to cause disproportionate alarm in parents.

Methods: We considered our experience of six children with mastocytosis together with a review of the literature to examine other reports of anesthesia in children with mastocytosis. Our literature search found 57 general anesthetics in 39 children with mastocytosis. In addition, we searched for information about current consensus in diagnosis, classification and treatment of mastocytosis and in vitro and in vivo studies looking at mast cell behavior in response to drugs commonly used during anesthesia.

Discussion: The literature search revealed that general anesthesia has precipitated life threatening complications in adult patients with systemic mastocytosis (SM) but no such complications have been described in children with mastocytosis. Our own experience with children with mastocytosis is of uneventful anesthesia. Advances in the understanding of the genetic basis of mastocytosis suggest that pediatric cutaneous mastocytosis (CM) and SM are different entities. SM in children is extremely rare and is associated with elevated baseline serum tryptase. There are few reports of anesthesia in this group.

Conclusion: The risks for most pediatric patients are overstated by mastocytosis websites. Most pediatric patients with CM do not appear to be at risk of widespread mast cell degranulation during anesthesia but because of the small number of cases reported, the risk cannot be ascertained with confidence. Children with SM and a high baseline serum tryptase (marker of mast cell burden) may merit extra precautions but experience in this subgroup is even more limited. Drugs which cause minimal histamine release can be selected from the range of drugs available in most pediatric centers without compromise to technique.