Incidence, timing, and significance of early hypogammaglobulinemia after intestinal transplantation.

Background: Despite recent advances in intestinal transplantation (ITx), infection (INF) and acute cellular rejection (ACR) remain major causes of patient and graft loss. Studies in other solid-organ transplantations indicate that low levels of serum immunoglobulin G (IgG) negatively impact outcomes. To date, there have been no studies on IgG after ITx.

Methods: A retrospective review of an IgG measurement protocol in primary ITx recipients between 2007 and 2011 was undertaken. IgG levels were measured at the time of evaluation, transplantation, and at weekly intervals for 2 months. Hypogammaglobulinemia (HGG) was defined as IgG levels below the lower limit of the 95% confidence interval for age. Associations between HGG, INF, and ACR were tested, and the incidence and timing of INF and ACR were compared.

Results: Thirty-four patients were transplanted at a mean (SD) age of 12.4 (17.2) years. Most were Latino children with gastroschisis who received multivisceral grafts. Relative to pre-ITx levels, a statistically significant decrease in IgG levels was observed after ITx (P<0.05). Twenty patients (59%) developed HGG during the post-ITx period at a mean (SD) of 9.8 days. No significant associations were identified between HGG and INF or ACR.

Conclusions: This is the first study to describe serum IgG levels after ITx. A marked decrease in serum IgG levels was observed early on, in most patients. The etiology is potentially related to immunotherapy. HGG was not associated with INF or ACR, possibly related to the sample size and our practice of exogenous intravenous immunoglobulin replacement.