Mounting evidence suggests cell cycle dysregulation is involved in the pathogenesis of Alzheimer's disease (AD) and that this failure is systemic, affecting not only neurons but also peripheral blood lymphocytes (PBLs). This study analyzed if differences in PBL proliferation activity could be used as a diagnostic biomarker for AD. CD69 and CD28 expressions on PBL T, B, and monocyte cells were measured by flow cytometry with and without mitogenic stimulation in healthy controls (HC), probable AD, and Parkinson's disease dementia (PDD) subjects. Univariate and multivariate scoring models were employed to evaluate the data relative to the clinical diagnoses. Eleven CD expression markers were significantly altered in AD subjects compared with a mixed pool of PDD and HC subjects using univariate models. Using multivariate models, seven CD expression markers were significantly altered in AD subjects compared with PDD subjects. Multivariate scoring demonstrated up to a 91% positive and 92% negative agreement with subject clinical diagnosis and had little correlation with the severity of dementia. Present findings suggest that with further development this analytical and multivariate modeling procedure could aid the current differential diagnosis of Alzheimer's disease.

A patient with a classical salivary gland benign lymphoepithelial lesion (BLL) that converted to a lymphoblastic lymphoma (LSA) localized to the salivary glands is described. The malignant transformation of the BLL was preceded by Dilantin anticonvulsant therapy, and in vitro tests subsequent to the development of LSA demonstrated positive Dilantin-induced lymphocyte transformation. The lymphoma was treated successfully by local irradiation, chemotherapy, and discontinuation of Dilantin. The case illustrates the "prelymphomatous" nature of BLL in certain patients, as well as the possible potential danger of Dilantin and other lymphoid-stimulating drugs in discussed. Further study of drugs capable lymphocyte transformation in patients with prelymphomatous disorders is warranted.