Electron microscopic reinvestigation of archival samples of peripheral blood lymphocytes of four patients with Finnish-variant late infantile neuronal ceroid lipofuscinosis (CLN5) showed inclusions with dark globules and particles showing fingerprint profiles. Findings, in contrast to an earlier report, show that the lymphocytes in this disease carry pathognomonic cytosomes like all other forms of neuronal ceroid lipofuscinosis in childhood.