Onchocerca armillata contamination of a bovine pericardial xenograft in a human patient with repaired tetralogy of Fallot

BackgroundBovine pericardial patches are used for many purposes, including facilitating right ventricular outflow tract reconstruction in patients with congenital heart disease. Here we present a case of parasitic contamination of a bovine pericardium used as a transannular patch during repair of tetralogy of Fallot 28 years prior at a hospital in China.MethodsThe patient presented to the University of Washington Medical Center for congestive heart failure and pulmonic regurgitation, and heart tissues including the xenograft pericardial patch were submitted to the Pathology Department and subsequently to the Comparative Pathology Program.ResultsThe pericardial parasitic nodules with intralesional adult nematodes and microfilaria in the bovine tissues were preserved at harvest by (presumed) glutaraldehyde fixation.ConclusionOnchocerca armillata parasitic pericardiopathy was diagnosed in the xenograft tissue based on the characteristic nematode morphology and the presumed geographic location of the donor bovine. This resulted in O. armillata contamination of the pericardial xenograft in a human patient with repaired tetralogy of Fallot.