Fetus with trisomy 13, holoprosencephaly, and renal dysplasia. (A) Cranial bases from two fetuses: to the left the fetus with trisomy 13, holoprosencephaly, and arhinencephaly; to the right a fetus aborted because of trisomy 21. To the left, there is absence of crista galli (arrow). Compare with the fetus to the right that has a normal crista galli. (B) H&E-stained section from the fetal retina (10× lens) demonstrates the presence of cartilage and multiple neuronal rosettes diagnostic of retinal dysplasia (arrows). (C) H&E-stained renal section with 2× lens, original magnification. There are numerous dilated tubules at the corticomedullary junction and three nodules of dysplastic renal parenchyma in the medulla. (D) A small nodule was noticed in the spleen that was sampled and histologically was a splenopancreatic fusion (H&E-stained section from the spleen,10× lens). Congenital Anomalies of the Kidney and the Urinary Tract (CAKUT): Rodriguez MM - Fetal and pediatric pathology (2014). Not altered. CC.