Differential diagnosis, dementia

The differential diagnosis of depression is organized along both symptomatic and causative lines. Symptomatically, major depression is differentiated from other disorders by its clinical presentation or its long-term history. This is, of course, the primary means of distinguishing psychiatric disorders in DSM-1V. The symptomatic differential of major depression includes other mood disorders such as dysthymic disorder and bipolar disorder, other disorders that frequently manifest depressed mood including schizoaffective disorder, schizophrenia, dementia, adjustment disorder, and post-traumatic stress disorder, and, finally, other nonpsychiatric conditions that resemble depression such as bereavement and medical illnesses like cancer or AIDS. 

Before diagnosing dementia, yon shonld consider any other condition that might impair intellectual function or that might masqnerade as an impairment of intellect. The differential diagnosis of dementia inclndes ... 

M.D. Devous Sr., Functional brain imaging in the dementias Role in early detection, differential diagnosis, and longitudinal studies, Eur. J. Nucl. Med. 29 (2002) 1685-1696. 

I. G. McKelth, Dopamine transporter loss visualized with FP-CIT SPEC In the differential diagnosis of dementia with Lewy bodies. Arch. Neurol. 61 (2004) 919-925. 

Figure 7.1 Differential diagnosis of dementia (AD = Alzheeners disease, DLBD dementia with Lewy body disorder, DLB = dementia with Lewy bodies)...

Delirium, toxic confusional state, metabolic encephalopathy or acute confusional state are terms that are used interchangeably and often loosely to describe a syndrome of acutely disordered cognition, sometimes associated with reduced level of consciousness and abnormal attention (see Table 32.1). The syndrome is very common, especially in the elderly and in patients with dementia, and presentations vary widely both in the speed of onset and severity (Siddiqi et al. 2006). The differential diagnosis is broad and includes almost any medical condition, but the commonest causes are sepsis, adverse drug reaction and metabolic derangement (Francis et al. 1990). 

Clinical Neuroproteomics of Human Body Fluids CSF and Blood Assays for Early and Differential Diagnosis of Dementia... 

Although in expert hands the clinical diagnosis of AD is predictive of AD pathology in 80-90% of cases, very early diagnosis of AD, and differential diagnosis of unusual presentations of patients with dementia remains difficult on clinical grounds. 

Non-neoplastic lesions are often evaluated by a neurologist. Thus, a major neurologic symptom (e.g., pain, weakness, or visual loss) or category of neurologic disease (e.g., dementia) may focus the differential diagnosis (Table 20.3). 

Differential diagnosis of dementia is important, although frequently neglected and avoided. Professionals who seek early and improved diagnosis of older individuals can contribute to an increased understanding and perhaps an eventual cure. 

Brain Perfusion Isopropyl- -iodoamphetamine (IMP) is a small molecule that crosses the blood—brain barrier with a good correlation with blood flow. It was first used to evaluate regional cerebral blood flow (rCBF) in differential diagnosis in psychiatric disorders and dementia (O Gonnell et al., 1989), and then to evaluate the severity of degenerative dementia (Ohnishi et al., 1991). 

Atlases can also be used to guide the selection of brain regions for more complex analyses (Gardner and Yazdani 1998 Nowinski 2004). We have used a simple coordinate system based on the position and size of the CSF space to allow automatic measurements of the position and severity of cerebral atrophy in patients with dementia. In this case the atlas is deliberately extremely simple and of very low spatial resolution identifying only the front, middle, back, top and bottom and right and left of the CSF space. Despite this, the distribution of CSF in this standard space allows differential diagnosis between dementias of different types with accuracy... 

Well-conducted therapeutic trials are highly dependent on adequate patient selection among the wide number of types of dementia. The question of differential diagnosis is thus raised. Alzheimer s disease is responsible for approximately 50% of all dementias [5]. 

Perfusion hexamethylpropyleneamine oxime (HMPAO) single-photon emission computed tomography (SPECT) or 2-[ F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) can be used to help to differentiate between Alzheimer s disease, vascular dementia and frontotemporal dementia if the diagnosis is in doubt. 

Diagnosis of cerebrovascular disease and differentiation of focal abnormalities in CBF typical in multi-infarct dementia and degenerative dementia... 

Clinically, the diagnosis is based on early signs of Parkinsonism, episodes of confusion and fluctuating performance and frequent psychiatric symptoms (delirium, hallucinations). If the dementia is relatively isolated, then clinically Lewy body disease cannot easily be differentiated from Alzheimer s disease. 

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