Nuclear Projections in Neutrophils for Supporting the Diagnosis of Trisomy 13

Trisomy 13 is a rare genetic disorder characterized by severe multiple congenital anomalies. Structural anomalies of neutrophils may be supportive for the diagnosis of trisomy 13. A newborn was born by vaginal delivery after 29 weeks of pregnancy. Physical examination revealed symmetric growth restriction, low-set hypoplastic ears, aplasia cutis congenita areata on the vertex, postaxial polydactyly of the foot, bilateral microphthalmia, an umbilical cord cyst, and heart murmurs. Echocardiography showed truncus arteriosus type I. Review of the peripheral blood smear revealed two or more small threadlike pedunculated projections attached to the surface of the nuclei in more than 60% of the neutrophils (Figure 1). The diagnosis of trisomy 13 was made by chromosomal analysis. The infant died at 2 days of life because of massive pulmonary hemorrhage.