neuroblog

The pigeonhole hazards

Facebooktwittergoogle_pluslinkedinmail

As a young man,I contracted bad amoebic infection while traveling overseas. I was treated but the symptoms persisted and I went to see the top gastroenterologist in New York, presumably one of the best in the world. He examined me and said, “Dont worry, it will go away.” “But what is it?,” I kept pressing for a diagnosis. “It is a garbage syndrome andit will go away,” was the famous doctor’s response. Many years later, I developed odd floaters in one of my eyes and went to see a famous opthalmologist, also presumably one of the best in the world. “Don’t worry, it will go away” he reassured me after a careful examination. Again, I kept pressing for a diagnosis, for a name. “It is stuff and it will go away.” In both instances the symptoms disappeard, just as the two famous doctors predicted. In both cases, the doctors refrained from affixing a dignostic label tothe clinical picture. For me, a practicing neuropsychologist, the two encounterswere also lessons in clinical wisdomvalidating my own approach to clinical diagnosis: don’t force a clinical pictureunder a particular diagnosticlabel when it does notfit any of the available labels naturally.

Mother Nature is under no obligation to abide our diagnostic taxonomies. The diversity of clinical presentations far exceeds the number of diagnostic categories offered by any diagnostic manual, including DMS. This is particularly true in neuropsychology and for two reasons. Firstly, the nature of cognitive impairment is determined by the underlying neuroanatomy of impairment more than by its etiology, and most etiologies are not neuroanatomically specific. Secondly, our taxonomies are an admixture of disorders (i.e. entities defined in terms of underlying causes – Parkinson’s disease is an example) and syndromes (i.e. entities defined as constellations of symptoms – ADHD is an example). Syndromes in particular are somewhat arbitrary constructs with permeable boundaries. Experienced clinicians understand this but members of the general public often don’t. “If doesn’t fit you must…” carefully describe the symptoms and make therapeutic recommendations to the extent possible. But by articificially forcing the case into a diagnostic pigeonhole where it does not belong you are creating an illusion of explanation rather than true explanation, and further clutter the illusion with the surplus assumptions often linked to the diagnostic label, which may me totally inapplicable to the case at hand. These thoughts often cross my mind when I encounter patients with the prior diagnoses of ADHD, autism, Aspergers and a few others…

EG

Related Posts