Catatonia and neuroleptic malignant syndrome: two sides of a coin?

Catatonia was first described by Kahlbaum in 1874. Ever since, the concept of catatonia has been the focus of debate, a major point of discussion being its nosological status. The question rises whether it is to be considered a syndrome with a wide variety of causes and clinical signs or a distinct clinical entity. Since catatonia shares a number of symptoms with the neuroleptic malignant syndrome (NMS) and similar treatments can be used in both conditions, it has also been suggested that NMS and catatonia are two variants of the same disorder In this article we describe five cases of catatonia and NMS in order to approach this nosological question. The clinical similarity between both syndromes is demonstrated in our cases. On the level of pathophysiology however, catatonia and NMS are quite different, with catatonia rather being a cortical psychomotor syndrome and NMS a subcortical motor disorder. Similarities can be explained by means of well-known models of basal ganglia function. The nosological problem, however; can only be resolved when the concept of catatonia is better defined.