Child Neuropsychiatry Division,
C. Mondino Foundation, IRCCS, University of Pavia, Italy.
INTRODUCTION
In the area of Pervasive developmental
disorders (PDD), as in other neuropsychiatric clinical fields,
diagnosis should be based on a systematic assessment of clinical
findings, pattern of onset and course, etiology and pathogenesis.
General agreement among workers on these aspects would provide
the basis for a more global classification system. However, within
the field of these disorders, there is in reality general disagreement
on the models that should be applied, since there is a lack of
well-substantiated experimental evidence on which they can be
based (Rutter & Schopler, 1992). lf there is agreement for
autism, which most workers accept to be a syndrome with an organic
basis about which however we lack specific knowledge, it is all
the more true as regards the other PDDS.
As a result of this situation
classificatory systems in which the descriptions are based only
on symptomatological and behavioural aspects have had great success:
DSM-III (APA, 1980), DSM-III-R (APA, 1987) and ICD-10 (WHO, 1992).
This type of approach is principally characteristic of the psychiatry
of the English-speaking world, but these classifications are now
more and more generally accepted.
Among those authors who recognise
the use of such classificatory systems as being the only possible
model in view of the present state of our knowledge, there is
however hot debate aimed at their improvement: DSM is in fact
an on-going project with an Advisory Commitee which still meets.
The task facing those who work on the problem is far from being
easy, since a classificatory system must satisfy a large number
of objectives which are often difficult to reconcile, because
clinical and research needs are often in contrast.
It is very important that there
should be a rigorous and consistent basis for research and epidemiology
so that syndromes may be grouped together or differentiated on
the basis of similar observational categories. This is the point
of view, for instance, that underlies the criticisms made of ICD-10
by Waterhouse et al. (1992) and Giliberg (1994) who note that
the WHO manual subsumes categories like Childhood autism (CA)
or Atypical autism (AA) under PDD on the basis of simple behavioural
aspects, and at the same time creates sub-categories for Rett
syndrome and Childhood disintegrative disorder. As regards these
latter, Rett syndrome can in some cases correspond to CA from
a symptomatological point of view, while Childhood disintegrative
disorder implies aspects which can be ascribed to neurological
deficfts. According to Waterhouse et al. (1992) the inclusion
of these two subgroups should suggest an additional internal axis
for diagnosis within the PDD. Rutter and Schopler (1992) replied
that from a clinical point of view these subgroups can be differentiated
on the basis of their course, and that it would be "absurdly
restrictive" to base a diagnostic system on a purely behavioural
approach, a cross-sectional clinical picture. They maintain that
it would be wrong to exclude Rett syndrome and Childhood disintegrative
disorder from PDD: these disorders present with a similar pattern
and the patients have similar needs.
Another topic of fierce debate
is the sensitivity and the specificity of the different systems.
It is now well known that DSM-III-R tends to overdiagnose autism,
since its inclusion criteria are rather wide, while DSM-III is
more restrictive and ICD-10 intermediate (Factor et al. 1989;
Hertzig et al. 1990; Spitzer & Siegel 1990; Volkmar et al.
1992); since a perfect system is not possible, it should be decided
a priori whether a tendency to produce false negatives
or false positives is preferable, particularly in those countries
where access to treatment is based on the label given to the syndrome
(Szatmary 1992).
The very term PDD has been questioned
(Baird et al. 1991; Gillberg 1991; Happé & Frith 1991)
along with the necessity of having further subgroups within the
heterogeneous category of PDD (Tsai 1992; Volkmar 1992, Waterhouse
et al. 1992; Rutter & Schopler 1992; Castelloe & Dawson
1993; Gillberg 1994; Rutter et al. 1994).
The interminable debate about
symptomatological classifications - and we have reported only
some aspects which seem important to us - has led to the preparation
of DSM-IV (Draft Version, APA 1993). As well as a different choice
of items compared to the previous version, this includes the subgroups
Rett syndrome and Childhood disintegrative disorder within PDD,
and, provisionally, Asperger's disorder, thus moving into line
with ICD-10. Furthermore the manual specifically indicates that
atypical forms of autism should be classified as Pervasive Developmental
Disorder not otherwise specified (PDDNOS), thus supporting the
possible continuity between autism and PDDNOS.
Child psychiatrists of the French schools are not involved in this debate, and criticise the premises which inspired the DSM and ICD10. Misès et al. (1988) maintain that DSM-III is not at all
atheoretical, but rather that
it is in line with the dominant paradigms of North American psychiatry,
which is cognitivist and behaviourist. They believe that is is
much more useful to try to produce a classificatory system which
takes into consideration the mobility or the fixedness of the
disturbances, the nature of the changes that underlie the symptom
and which develop through time, the risk of sliding into an adult
mental pathology, all of which based on precise psychopathological
criteria, the psychoanalytical framework which is traditional
in the French child psychiatry. Other workers have supported
this position of Misès et al. (Lebovici 1988; Bursztein
et al. 1990; Touati et al. 1990), and have introduced a number
of themes which are in clear opposition to the premises which
led to the APA and WHO classifications: the analysis of the structural
organisation and its disturbance which lie behind the symptom,
the importance of the family context, the revaluation of subjectivity
and intuition as valid clinical tools, the concept of psychosis
as a psychopathological continuum with its own course, in contraposition
to the definition of PDD and to the "tendency to place autism
and childhood psychoses within a deficitary dimension" (Touati
et al. 1990).
The French classification of the
mental disorders of children and adolescents (CFTMEA, Misès
et al. 1988) is offered as an alternative proposal to the DSMs
and ICD-10 in the light of the considerations reported above;
it reproposes the term "Childhood psychoses" in the
place of PDD and leaves the psychiatrist free to make a diagnosis
on the basis of his experience, without the limit of a checklist.
We believe that an approach that
is as open as possible to the different schools of thought as
regards diagnosis and classification is important for our clinical
and diagnostic practice. The combined use of the different classificatory
systems which we have discussed in this introduction and in a
previous paper (Bettaglio et al., in press) could give additional
information about individual cases. For us DSM-III-R and ICD-10
are an agile tool for initial clinical screening, and allow comparisons
to be made with data reported in the international bibliography,
while CFTMEA and the Operational Classification proposed by Manzano
and Palacio-Espasa (1983) are indispensable because of their psychopathological
orientation, which is often close to that of the Services to which
our patients are referred for treatment.
This study compares the diagnoses
obtained using the above-mentioned classificatory systems (DSM-III-R,
ICD-10, CFTMEA and the Operational Classification of Manzano and
Palacio-Espasa) on a population of 20 paediatric subjects; the
recently published draft version of DSM-IV is also used and the
qualitative differences compared to the previous version are tested.
MATERIALS AND METHODS
We examined 20 children, 17 males and 3 females aged between 2 years 9 months and 7 years 7 months (average age 5 years 2 months), admitted consecutively to the Child Neuropsychiatry Division of the Universfty of Pavia for a diagnostic and therapeutic assessment. The protocol used for the diagnostic assessment of the patient inciudes: anamnestic investigation, neuropsychiatric examination, a battery of instrumental and laboratory tests (routine hematochemical tests, lactic acid dosage, thyroid hormones, immunogiobulins for the TORCH complex, plasma and urine amino acids, caryotype for fragile X, EEG awake and sleeping, visual and brainstem auditory evoked potentials, cranial CT or MR). On the basis of our findings we applied the diagnostic criteria proposed by DSM-III-R and assumed as the criterion for inclusion in our study a diagnosis of PDD, either of the subtype AD or PDDNOS. We then compiled the BSE scale (Barthélémy et al. 1990) on the basis of at least one week's observation during hospitalisation. We also assessed cognitive development using Griffiths' Mental Development Scales (Griffiths 1986). We also performed a standardised psychodynamic observation (SPO) according to the following protocol:
- video recorded observation of a semi-structured interview with the mother (or mother and father) and the child;
- video recorded observation of a series of sessions of the child whith the neuropsychiatrist;
- team viewing of the films with
interpretation of the behaviour according to fixed parameters.
On this basis we elaborated a
structural diagnostic matrix according to Palacio-Espasa, in function
of the SPO and with reference to the findings of each of the parameters.
In the light of this work-up we
first verified the diagnoses that had previously been made according
to DSM-III-R, and then we applied four other diagnostic classifications:
the recent DSM-IV, ICD-10, CFTMEA, and the classification proposed
by Manzano and Palacio-Espasa.
RESULTS
According to DSM-III-R, 12 of
the 20 subjects examined were diagnosed as AD and the remaining
8 as PDDNOS. According to DSM-IV only 7 were DA and 13 were PDDNOS,
of which 5 were diagnosed as AA; DSM-III-R had classified these
five cases as AD. ICD-10 found 8 cases of CA, 4 AA, and 8 Other
syndromes of global alteration of psychological development.
CFTMEA found only 2 cases of Kanner's Precocious CA, 6 as Other
forms of CA, 6 as Precocious deficitary psychosis, and 6 as Psychotic
disharmony. According to Manzano and Palacio-Espasa's classification
there were 2 cases of Primary autism, 2 of Secondary autism, 5
of Disorganising psychosis (typical form), and 6 of Precociously
deficitary psychosis, while for 5 cases it was not possible to
formulate a diagnosis since according to the criteria they presented
as transitional forms, and were therefore without the necessary
and sufficient characteristics for insertion into a precise diagnostic
category.
DISCUSSION
The criterion for inclusion of
subjects in our sample was a diagnosis of PDD following DSM-III-R.
This classification subdivides PDD into AD and PDDNOS. Our experience
in evaluating our cases was that the two diagnostic criteria are
well differentiated. In particular the description of the single
items with regard to AD and the criteria that are specified for
assignment to this category allowed us to differentiate this group
quite clearly; all the same there are children in this group who
are classified differently by the other classifications we considered,
and these are above all the cases that Misès et al. and
Manzano and Palacio-Espasa call Precocious deficitary psychoses.
Only in two cases did AD according to DSM-III-R correspond to
the same diagnosis in all the other systems (AD for DSM-IV, CA
for ICD-10, Kanner's Precocious CA for CFTMEA, and Primary autism
for Manzano and Palacio-Espasa). Together these describe a serious
picture of autism which is deeply rooted. Our quantitative (importance
of the disorder) and qualitative (underlying intrapsychic and
relational functioning) work-up showed us that the cases defined
as AD within DSM-III-R presented, beyond the symptomatological
aspects, deeply differing characteristics. Indeed it was possible
to show different profiles and residual areas of cognitive and
relational functioning which were not equivalent. This finding
seems to us not only to be fundamental in a diagnostic sense,
but also in prospect of treatment program which will be different
in relation to the potentialities and residual areas of functioning
of each child.
The category PDDNOS is substantially
defined by a criterion of exclusion. The qualitative impairment
in the development of reciprocal social interaction and verbal
and non-verbal communication skills which marks PDDNOS remains
vague. The inclusion of all those forms which cannot be diagnosed
as AD within PDDNOS means that within this subgroup there are
clinical situations that differ widely also from the behavioural
point of view, exactly because the qualitative characteristics
of the impairment are vaguely defined. The behavioural differences
are confirmed by further investigation of the cognitive, affective
and relational aspects. The Psychotic disharmony described by
Misès et al. and Manzano and Palacio-Espasa's Disorganising
Psychosis (typical form) both fall within this category.
Similar considerations may be
made concerning DSM-IV, in as much as the parameters for inclusion
in AD and PDDNOS do not seem to have been formally changed. However
AA is included within the latter category, which covers the cases
which do not fulfil the criteria for AD because of a later age
at onset of the symptomatology, an atypical or less serious symptomatology
or for all of these reasons. In this study we therefore used
this diagnostic category to differentiate those cases in which
the quantitative and qualitative impairment of the social interaction
appeared to be clinically less serious compared to those which
were classified as AD or in whom the age of onset was of over
three years. For this reason, in order to make our observational
criteria more objective, as well as using clinical assessment
we also based ourselves on the scores in the BSE scale, particularly
with regard to those items that Barthélémy et al.
(1990) consider to be specific indicators of the autistic symptomatology.
Following these criteria only 7 of the 12 children who were diagnosed
as AD according to DSM-III-R were assigned the same diagnosis
by DSM-IV, while the other 5 were defined as AA and therefore
assigned to PDDNOS. This use of DSM-IV thus leads to an underestimate
of the autistic disorder compared to both DSM-III-R and ICD-10.
We therefore believe that a is necessary that the definition
and way that this category is to be used should be specified better,
as is the case in ICD-10, which differentiates AD qualitatively
from AA (in which the deficitary aspects prevail) and does not
leave the diagnostic classification as arbitrary (atypical symptomatology,
subthreshold symptomatology). In other words we believe that
it would be more useful if AA was a further subgroup of PDD than
to further widen the heterogeneity of the patterns that are classifiable
as PDDNOS.
For the cases we studied PDDNOS/AA
always corresponds to CA according to ICD-10; it seems to be comparable
to Other forms of CA in the CFTMEA classification and covers most
of the cases which could not be defined by the Manzano and Palacio-Espasa
system in as much as they presented as transitional forms. PDDNOS
is however a category defined by exclusion, which subsumes situations
which are very different also behaviourally. The cases diagnosed
as PDDNOS by DSM-III-R were assigned the same diagnosis by DSM-IV.
As regards DSM-IV our quantitative
and qualitative work-up showed that AD itself inciuded cases that
differed in their mental and relational functioning. This differentiation
was even more obvious when we considered those cases which were
classified as PDDNOS.
In general our experience shows
that DSM-IV allows a more precise clinical definition compared
to DSM-III-R, in as much as it introduces new diagnostic categories
which it is perhaps worth getting to know better through more
long-term use and thus greater experience.
In the same way ICD-10 operates
a distinction between Autistic disorder and Other syndromes of
global alteration of psychological development. The criteria for
the definition of CA are substantially similar to those proposed
by the APA classifications, even if they are understood as reference
points for a more general diagnosis. In the same way the definftion
of Other syndromes of global alteration of psychological development
could be assimilated to that of PDDNOS in DSM-III-R and IV, in
as much as their inclusion criteria are not specified and they
are differentiated by exclusion from the other forms described.
In our cases PDDNOS always corresponded to this category in ICD-10.
AD corresponds to CA and AA as defined by ICD-10, this latter
characterised by a prevalence of cognitive deficits or by a specific
language impairment, so that it is thus more similar to the Precocious
deficitary psychosis describes by Misès and to Precociously
deficitary psychosis in Manzano and Palacio-Espasa's system.
None of the cases we considered could be classed in the other
categories described by ICD-10. Our work-up as regards mental
and affective relational functioning substantially confirmed these
considerations, contributing to further differentiate the children.
CFTMEA seems to be very accurate
in identifying the different types of childhood psychosis, and
as well as the behavioural aspects it also concentrates on certain
aspects of the mental functioning of the subject, so that its
definftion of the category goes beyond purely symptomatological
aspects. As we have already said, in our cases Precocious childhood
autism corresponds to AD, the Other forms of childhood autism
to AA in DSM-IV, and Psychotic disharmony to PDDNOS, while our
cases of Precocious deficitary psychosis go under AD, apart from
n.7 and n.17 who did not present autistic symptoms. This classification,
unlike the others, includes a second axis which covers associated
or previous, and perhaps etiologic, factors. It therefore allows
cases to be classified on this basis, that is also to show up
particular family or development situations, and the presence
of organic aspects, aspects which we considered when working-up
our clinical cases.
We adopted Manzano and Palacio-Espasa's
method of assessing intrapsychic aspects: the classification which
they propose is specifically designed to define each case dynamically.
However it was often difficult to classify individual patients
according to their diagnostic categories. For five patients a
diagnosis was not made using the Manzano and Palacio-Espasa system
since they represented situations which, in terms of their approach,
were characterised and differentiated by the presence of elements
which were developing, that is they were transaional between forms.
Highly specific definitions are difficult to adapt to clinical
situations which are often not so clear. In our cases Primary
autism corresponded to Precocious lnfantile Autism (CFTMEA) and
AD; Secondary autism and Disorganising psychosis are very specific
definitions although for some aspects they can be related to Other
forms of childhood autism and Psychotic disharmony (CFTMEA), respectively.
CONCLUSIONS
Our data lead us to make a number
of considerations, and these are primarily methodological: it
is useful to to adopt tools which allow different levels of assessment,
so as to be able to generate an overall picture which is different
for each patient and constitutes not only a diagnostic assessment,
but also gives indications for treatment and prognosis. We have
tried to show up the different characteristics of the classification
systems which we used, differences which also depend on the different
theoretical premises on which they are based. Our clinical experience
shows the usefulness of DSM-III-R, DSM-IV and ICD-10 for initial
screening, in view of their high sensitivity. Further study on
the use of DSM-IV is necessary; at this point the possibility
of greater differentiation, not only between different situations
but also in relation to the degree of impairment, seems to us
to be clinically useful. The other two systems were necessary
for the specific classification of all those forms of childhood
psychosis which are not described by the former classifications
and to understand the functioning of each patient: CFTMEA meets
these needs and also allows the enhancement of the associated
or anamnestic factors that are present, while clinical use of
the system proposed by Manzano and Palacio-Espasa seems to be
complex, as it presupposes a long and in-depth psychodynamic training.