Ocular pathology of infantile Niemann-Pick disease. Study of fetus of 23 weeks' gestation.

A fetus of 23 weeks' gestation was aborted following the demonstration of sphingomyelinase deficiency (infantile form of Niemann-Pick disease) in cultured amniotic fluid cells that were obtained by amniocentesis. Histopathologic study of the eyes disclosed normal findings for the fetal age, except for fine lipid droplets in the inner plexiform layer of the retina. By electron microscopy, membranous cytoplasmic bodies (MCB) characteristic of lipid storage diseases were identified in many ocular tissues, including corneal epithelium and keratocytes, lens epithelial cells and fibroblasts of choroid and sclera, and in extraocular muscle. Selective accumulation of MCB in ganglion cells in the primitive macular region was not apparent. An extremely fine membranous component (30 to 40 Angstroms) was seen in some inclusions, suggesting a relatively pure phospholipid content.