RESUMO
O envelhecimento da população e o aumento da expectativa de vida resultam em um número cada vez maior de pacientes com demência. Os déficits cognitivos podem ser manifestações de uma doença curável do sistema nervoso central (por exemplo, neuroinflamação), como também de uma doença atualmente considerada irreversível, como a doença de Alzheimer (DA). Tendo em vista as novas abordagens terapêuticas para a DA, em que se avalia o potencial modificador da patogenia, torna-se necessário o estabelecimento de um diagnóstico confiável em vida. Embora a análise do líquido cefalorraquidiano (LCR) e do soro seja realização de rotina em doenças neuroinflamatórias, ainda necessita de padronização para ser usada como instrumento auxiliar no diagnóstico clínico da DA. Vários parâmetros relacionados à DA (tau total, formas fosforiladas de tau, peptídeos Aβ, genótipo ApoE, p97 etc.) podem ser determinados no LCR. A combinação de alguns desses parâmetros proporciona sensibilidade e especificidade na faixa de 85 por cento para o diagnóstico da DA, um valor usualmente atribuído a um bom instrumento de diagnóstico. Nesta revisão, são discutidas as publicações mais recentes sobre os marcadores neuroquímicos para o diagnóstico clínico das demências, com ênfase no diagnóstico precoce e diferencial da DA. Discutem-se brevemente as novas perspectivas oferecidas por tecnologias recentes, tais como a FCS (fluorescence correlation spectroscopy) e a técnica de espectrometria de massa pelo método SELDI-TOF (surface enhanced laser desorption/ionization time-of-flight mass spectrometry).
Aging of population, and increasing life expectancy result in an increasing number of patients with dementia. This symptom can be a part of a completely curable disease of the central nervous system (e.g, neuroinflammation), or a disease currently considered irreversible (e.g, Alzheimer's disease, AD). In the latter case, several potentially successful treatment approaches are being tested now, demanding reasonable standards of pre-mortem diagnosis. Cerebrospinal fluid and serum analysis (CSF/serum analysis), whereas routinely performed in neuroinflammatory diseases, still requires standardization to be used as an aid to the clinically based diagnosis of AD. Several AD-related CSF parameters (total tau, phosphorylated forms of tau, Aß peptides, ApoE genotype, p97, etc.) tested separately or in a combination provide sensitivity and specificity in the range of 85 percent, the figure commonly expected from a good diagnostic tool. In this review, recently published reports regarding progress in neurochemical pre-mortem diagnosis of dementias are discussed with a focus on an early and differential diagnosis of AD. Novel perspectives offered by recently introduced technologies, e.g, fluorescence correlation spectroscopy (FCS) and surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) are briefly discussed.
Assuntos
Consenso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/sangue , Biomarcadores , Transtornos Cognitivos/diagnóstico , Diagnóstico DiferencialRESUMO
INTRODUCTION: Simultaneously with the origin and development of the Cuban epidemic neuropathy, cases of viral meningoencephalitis with particular characteristics due to Coxsackie were found. This virus and Inoue-Melnick virus were found too in patients suffering from Cuban epidemic neuropathy. PATIENTS AND METHODS: 31 pediatric patients suffering from viral meningoencephalitis were studied. Albumin, IgA, IgM and IgG were quantified in serum and cerebrospinal fluid by nephelometry. Cytochemical studies and reibergrams were performed. RESULTS: There was a lymphocyte predominance in cerebrospinal fluid. A dysfunction of blood-cerebrospinal fluid barrier was shown in 10 patients. Twenty patients have no immunoglobulins intrathecal synthesis. The synthesis patterns were: five patients with local IgM synthesis, two patients with local IgG synthesis and IgA + IgM. IgA + IgG and IgA + IgM pattern was synthesized in one patient respectively. Two patients with low IgG synthesis percentage or IgG intrathecal fractions were reported. CONCLUSIONS: The absence of immunoglobulins intrathecal synthesis and the immunoglobulins synthesis patterns differ from other pediatric patients with enterovirus meningoencephalitis. These patterns may have relationship with modified antigenic characteristics of the virus, also found in Cuban epidemic neuropathy.