Hippocampal sclerosis and ubiquitin-positive inclusions in dementia lacking distinctive histopathology.

The aim of this study was to determine the frequency of ubiquitin-positive inclusions (UPI) in dementia lacking distinctive histology (DLDH), and their relationship to other pathologic features, such as hippocampal sclerosis (HpScl), as well as genetic factors. Routine and immunohistochemical studies were carried out in a consecutive series of 29 cases of DLDH. 83% of the cases had UPI, while HpScl was demonstrated in 76%. There was no significant correlation among pathologic features or between pathologic features and genetic factors. The high prevalence of UPI demonstrated in this study implies that DLDH is similar to motor neuron disease inclusion dementia. The high prevalence of HpScl may be the cause of some of the clinical features observed in patients with frontotemporal lobar degeneration.