http://www.neurology.org/content/51/6/1546.full#sec-3
The clinical criteria are set out in lists 1 through 4. The criteria for each of the three major clinical syndromes are divided into sections. The clinical profile statement together with the core clinical inclusion and exclusion features provide the necessary foundation for diagnosis. Additional clinical features, neuropsychological investigation, and brain imaging support the clinical diagnosis. Operational definitions of specific features are outlined later.
The clinical criteria are set out in lists 1 through 4. The criteria for each of the three major clinical syndromes are divided into sections. The clinical profile statement together with the core clinical inclusion and exclusion features provide the necessary foundation for diagnosis. Additional clinical features, neuropsychological investigation, and brain imaging support the clinical diagnosis. Operational definitions of specific features are outlined later.
Clinical profile. This statement (seen in lists 1 through 3) summarizes the neurobehavioral profile necessary to fulfill criteria for diagnosis.
Core diagnostic features. These are features (see lists 1 through 3) integral to the clinical syndrome. All features must be present to fulfill the
criteria for diagnosis.
Supportive diagnostic features.
Clinical.
These are features (see lists 1 through 3) that are not present in all
patients, or they may be noted only during one phase
of the disease. They are therefore not necessary
conditions for diagnosis. Supportive features are characteristic, often
with
high diagnostic specificity, and their presence
adds substantial weight to the clinical diagnosis. The diagnosis becomes
more
likely when more supportive features are present.
Physical.
In each of the clinical syndromes physical signs are few in contrast to
the prominent mental changes. Parkinsonian signs
typically emerge only during late disease. The
physical features outlined should be regarded as "supportive" rather
than as
necessary conditions for diagnosis.
Investigations.
Formal neuropsychological assessment, EEG, and brain imaging each can
provide support for and strengthen the clinical diagnosis.
Such investigatory techniques are not available
universally, and ought not to be considered a prerequisite for
diagnosis.
When neuropsychological assessment is performed,
the profile of deficits must demonstrate disproportionate executive
dysfunction
in FTD or disproportionate language/semantic
breakdown in PA and SD. With regard to brain imaging, the patterns of
abnormality
are characteristic, but not seen invariably. For
example, prominent atrophy of the temporal lobes is well visualized by
high-resolution
MRI, but may be undetected by CT. Failure to
demonstrate the prototypic appearances on imaging need not result in
diagnostic
exclusion.
Supportive features common to each of the clinical syndromes.
These features (see list 4) support but are not a necessary condition
for FTLD. Onset of disease is most commonly before
the age of 65 years, although rare examples of
onset in the very elderly have been reported. A positive family history
of
a similar disorder in a first-degree relative has
been reported2,4 in as many as 50% of patients: Some families have shown mutations on chromosome 17 or linkage to chromosome 3. Motor neuron
disease is a recognized albeit uncommon accompaniment to the clinical syndromes of lobar degeneration.42-47
The development of motor neuron disease in patients presenting with a
progressive behavioral or language disorder would strongly
support a clinical diagnosis of FTD or PA
respectively.
Exclusion features common to each clinical syndrome.
Clinical. All features (see list 4) must be absent. Early severe amnesia, early spatial disorientation, logoclonic speech with loss
of train of thought, and myoclonus are features designed to exclude AD.
Investigations. All features should be absent (when the relevant information is available).
Relative diagnostic exclusion features.
These are features (see list 4) that caution against but do not firmly
exclude a diagnosis of FTLD. A history of alcohol
abuse raises the possibility of an alcohol-related
basis for a frontal lobe syndrome. However, excessive alcohol intake may
also occur in FTD patients as a secondary
manifestation of social disinhibition or hyperoral tendencies. The
presence of vascular
risk factors such as hypertension ought to alert
investigators to a possible vascular etiology. Nevertheless, such risk
factors
are common in the general population and may be
present coincidentally in some patients with FTLD, particularly in those
of
more advanced age.
List 1 The clinical diagnostic features of FTD: Clinical profile
Character change and dirordered social
conduct are the dominant features initially and throughout the disease
course. Instrumental
functions of perception, spatial skills, praxis,
and memory are intact or relatively well preserved.
-
Core diagnostic features
-
Insidious onset and gradual progression -
Early decline in social interpersonal conduct -
Early impairment in regulation of personal conduct -
Early emotional blunting -
Early loss of insight -
Supportive diagnostic features
-
Behavioral disorder
-
Decline in personal hygiene and grooming -
Mental rigidity and inflexibility -
Distractibility and impersistence -
Hyperorality and dietary changes -
Perseverative and stereotyped behavior -
Utilization behavior
-
-
Speech and language
-
Altered speech output
-
Aspontaneity and economy of speech -
Press of speech
-
-
Stereotype of speech -
Echolalia -
Perseveration -
Mutism
-
-
Physical signs
-
Primitive reflexes -
Incontinence -
Akinesia, rigidity, and tremor -
Low and labile blood pressure
-
-
Investigations
-
Neuropsychology: significant impairment on frontal lobe tests in the absence of severe amnesia, aphasia, or perceptuospatial disorder -
Electroencephalography: normal on conventional EEG despite clinically evident dementia -
Brain imaging (structural and/or functional): predominant frontal and/or anterior temporal abnormality
-
List 2 The clinical diagnostic features of progressive nonfluent aphasia: Clinical profile
Disorder of expressive language is the dominant feature initially and throughout the disease course. Other aspects of cognition
are intact or relatively well preserved.
-
Core diagnostic features
-
Insidious onset and gradual progression -
Nonfluent spontaneous speech with at least one of the following: agrammatism, phonemic paraphasias, anomia -
Supportive diagnostic features
-
Speech and language
-
Stuttering or oral apraxia -
Impaired repetition -
Alexia, agraphia -
Early preservation of word meaning -
Late mutism
-
-
Behavior
-
Early preservation of social skills -
Late behavioral changes similar to FTD
-
-
Physical signs: late contralateral primitive reflexes, akinesia, rigidity, and tremor -
Investigations
-
Neuropsychology: nonfluent aphasia in the absence of severe amnesia or perceptuospatial disorder -
Electroencephalography: normal or minor asymmetric slowing -
Brain imaging (structural and/or functional): asymmetric abnormality predominantly affecting dominant (usually left) hemisphere
-
List 3 The clinical diagnostic features of semantic aphasia and associative agnosia (SD): Clinical profile
Semantic disorder (impaired
understanding of word meaning and/or object identity) is the dominant
feature initially and throughout
the disease course. Other aspects of cognition,
including autobiographic memory, are intact or relatively well
preserved.
-
Core diagnostic features
-
Insidious onset and gradual progression -
Language Disorder characterized by
-
Progressive, fluent, empty spontaneous speech -
Loss of word meaning, manifest by impaired naming and comprehension -
Semantic paraphasias and/or
-
-
Perceptual disorder characterized by
-
Prosopagnosia: impaired recognition of identity of familiar faces and/or -
Associative agnosia: impaired recognition of object identity
-
-
Preserved perceptual matching and drawing reproduction -
Preserved single-word repetition -
Preserved ability to read aloud and write to dictation orthographically regular words -
Supportive diagnostic features
-
Speech and language
-
Press of speech -
Idiosyncratic word usage -
Absence of phonemic paraphasias -
Surface dyslexia and dysgraphia -
Preserved calculation
-
-
Behavior
-
Loss of sympathy and empathy -
Narrowed preoccupations -
Parsimony
-
-
Physical signs
-
Absent or late primitive reflexes -
Akinesia, rigidity, and tremor
-
-
Investigations -
Neuropsychology
-
Profound semantic loss, manifest in failure of word comprehension and naming and/or face and object recognition -
Preserved phonology and syntax, and elementary perceptual processing, spatial skills, and day-to-day memorizing
-
-
Electroencephalography: normal -
Brain imaging (structural and/or functional): predominant anterior temporal abnormality (symmetric or asymmetric)
List 4 Features common to clinical syndromes of FTLD (extension of lists 1 through 3)
III. Supportive features
Onset before 65 years: positive family history of similar disorder in first-degree relative
Bulbar palsy, muscular weakness and wasting, fasciculations (associated motor neuron disease present in a minority of patients)
IV. Diagnostic exclusion features
Historical and clinical
-
Abrupt onset with ictal events -
Head trauma related to onset -
Early, severe amnesia -
Spatial disorientation -
Logoclonic, festinant speech with loss of train of thought -
Myoclonus -
Corticospinal weakness -
Cerebellar ataxia -
Choreoathetosis
Investigations
-
Brain imaging: predominant postcentral structural or functional deficit; multifocal lesions on CT or MRI -
Laboratory tests indicating brain involvement of metabolic or inflammatory disorder such as MS, syphilis, AIDS, and herpes simplex encephalitis
V. Relative diagnostic exclusion features
Typical history of chronic alcoholism
Sustained hypertension
History of vascular disease (e.g., angina, claudication)
