Catatonia and neuroleptic malignant syndrome

Sir: Carey et al (Psychiatric Bulletin, February 2002, 26, 68-70) discussed the clinical issues surrounding a patient with features of catatonia and neuroleptic malignant syndrome (NMS). The relationship between the two conditions has been conceptualised in three ways. Castillo et al (1989) argue that lethal catatonia and NMS can be distinguished by clinical features, especially lead-pipe rigidity. Mann et al (1986) state that lethal catatonia is a syndrome that may have many causes, one of which is NMS. Bristow and Kohen (1996) regard catatonia as a risk factor for the development of NMS and lethal catatonia being identical to NMS.

The literature is less informative about the longitudinal features of both conditions. NMS recurs in a minority of patients and catatonia can recur. Although there is a consensus on the avoidance of neuroleptics in the acute stages of both conditions, there is little research to guide clinicians on their long-term management. The patient that the authors discussed experienced a relapse while treated with risperidone and lithium and they do not state the follow-up period after the second episode. The re-introduction of neuroleptic treatment after a near fatal episode of NMS or lethal catatonia appears to be associated with a high risk. Prospective data are needed on patients re-challenged with neuroleptics versus those in whom neuroleptics are withheld in order to help establish whether the conditions may be differentiated and to clarify the long-term risks and benefits of neuroleptic treatment.