Protein-losing enteropathy after fontan surgery: is assessment of risk patients with immunological data possible?

BACKGROUND Protein-losing enteropathy (PLE) is a late complication of the Fontan type surgery for univentricular heart characterized by massive enteric protein loss. The pathogenesis of PLE is not fully understood, and it is unclear why the onset of PLE varies widely and occurs months or even years after surgery. Besides characteristic laboratory findings, a typical cellular feature concerns the almost selective loss of CD4(+) lymphocytes at an only slightly changed CD8(+) lymphocyte count. The present pilot study aimed to test whether immunological or laboratory parameters differ in patients at risk for PLE. METHODS From children (n = 15) with Fontan type circulation, extensive cellular, humoral, and clinical laboratory data were analyzed. Patients without enteric protein loss (group I, n = 8), with transient phases of enteric protein loss in the absence of gastric infections (group II, n = 6), and one PLE patient (group III) were distinguished. The 90 data columns obtained in phases with normal serum protein levels were compared. RESULTS Clear differences were apparent between patients prior to PLE onset (group III), patients that in at least one occasion exhibited PLE signs (group II), and patients without detectable PLE signs (group I). The most discriminatory parameters between the three patient groups were NK and CD8(+)TCRalphabeta(+), CD8(+)TCRgammadelta(+) cell counts, including sL-selectin, IgE, and Ca(2+) (average recognition index = 91.5%, negative/positive prediction/sensitivity/specificity > 83%). CONCLUSIONS The results of this study seem to provide access to the early detection of PLE patients.