The significance of cytoplasmic inclusions in late infantile and juvenile amaurotic idiocy

Summary The electron microscopic findings of cerebral biopsies from two siblings with late infantile-juvenile amaurotic idiocy are presented. One patient had a mixture of fingerprint and multilamellar inclusions, often in the same cytosome. The second patient had only fingerprint inclusions.Electron microscopic findings in autopsied tissues from two other cases of late infantile-juvenile amaurotic idiocy with multilamellar cytosomes are also presented. Evolution of the multilamellar cytosomes into lipofuscin was not observed. We concluded that cases of late infantile-juvenile amaurotic idiocy with multilamellar and fingerprint inclusions should be distinguished from cases with lipofuscin.The present investigation was supported by Research Grants NS 05572-08, 1 T01 NS 05712-01 and RR 75.