[Foundations of the diagnosis of clinical syndromes]

The aim of this paper is to offer a reflection on the principles used to define a syndromic entity and for the evaluation of its manifestations and the aetiopathogenesis.

First, the paper looks at several of the different definitions of syndrome available and examines which are the essential features for this term to be employed in a clinical entity. The topographical and semiological perspectives are then dealt with, so as to be able to sort clinical syndromes and charts are used to offer representative examples. The main deficiencies in the use of terms to describe syndromes and the possible causes of such situations are also investigated. Following that, the chief semiological aspects in the diagnosis of a syndrome are assessed. Emphasis is placed on the factors that influence the variability of clinical behaviour, on the factors that come to bear on the recognition of the manifestations using the research methods available to us, on the rule of iterative confirmation of the symptom and on the characterisation and coordination of the symptom with other related phenomena. Lastly, the aetiopathological foundations of clinical syndromes are evaluated. We highlight the importance of determining the underlying anatomofunctional disorder, the classical distinctions concerning this, and the relation between syndrome and disease. The diagnostic criteria from numerous neurological syndromes are used as examples.

The concept of syndrome has been defined in an attempt to illustrate the presence of inappropriate, incorrect terms with adverse repercussions in the theoretical and practical areas. We also propose ways of resolving the faults found.