HYPOPLASTIC THYMUS AND T-CELL REDUCTION IN EECUT SYNDROME

We report on a patient with EEC/EECUT syndrome and concomitant hypopla sia of the thymus and reduction of T cells in secondary lymphatic orga ns. The patient was born prematurely at 35 weeks of gestational age an d exhibited ectodermal dysplasia, ectrodactyly, cleft palate and urina ry tract abnormalities. On the left side, a large ureterocele was pres ent, On the right side, an atretic meter was found, Both conditions ha d led to intrauterine hydronephrosis, renal dysplasia, oligohydramnios , pulmonary hypoplasia, and death of the child. Ureteral malformations are thought to be of epithelial origin. Autopsy showed only small rud iments of thymic tissue containing single epithelial cells, but were c ompletely devoid of Hassall corpuscules. Again, this clearly points to an ectodermal defect. Although there was severe reduction of T cells in secondary lymphatic organs, the thymic defect would not have necess arily led to immunological deficiency; perhaps this is the reason that an epithelial defect in the thymus of patients with EEC syndrome has not yet been reported, With regard to an updating of the diagnosis of the EEC/EECUT syndrome, an ''EEC/EECUT plus'' syndrome is suggested. ( C) 1997 Wiley-Liss, Inc.