Status dystonicus: under-recognized and under-treated.

Abstract

The word ‘status’ usually provokes an almost Pavlovian reaction in healthcare professionals, since they are trained to provide an emergency response. Status epilepticus and status asthmaticus are both recognized to require urgent attention, and there are generally accepted management guidelines which follow a stepwise approach and end up (if needed) with admission to an intensive care unit. Strangely though, while status dystonicus is equally serious, can be life-threatening, and is undoubtedly very unpleasant for the person concerned, it has not received the same level of attention. This has led to a number of inadequacies in the provision of care. The first problem is the absence of an accepted definition. An early and still quoted suggestion is the development of increasingly frequent and severe episodes of generalized dystonia which necessitate urgent hospital admission.1 This is both self-fulfilling and imprecise. However, subsequent papers on the topic either use this terminology or do not give any definition at all.2-4 In general, patients are reported who experience recurrent or occasionally sustained muscle contractions or spasms (which can be focal or generalized), that cause abnormal posturing. There is no agreed duration, either for individual spasms or overall. In epilepsy, episodes lasting more than 5 minutes, or three or more episodes in an hour, are now considered to be status, and it would make matters simpler if this or something similar could be applied to dystonic spasms as well. Without a standard definition, it is inevitable that the condition will be under-recognized and under-treated. This is difficult to prove as there have not been any large-scale studies: most reports still consist of relatively small retrospective case series followed by a review of other papers. Exactly the same situation held for both epilepsy and asthma a few decades ago, which at the time were also under-recognized and under-treated. Case series also frequently state that it is a rare condition, but this could be as much a result of a failure of diagnosis as a genuinely low incidence. A standard definition should also formally distinguish status dystonicus from conditions such as oculogyric crisis, neuroleptic malignant syndrome, paroxysmal autonomic instability with dystonia, or decerebrate posturing. The patients at risk are well characterized, and are mainly those with chronic dystonia, especially bilateral cerebral palsy, other dystonias, and various neurodegenerative disorders. Exacerbations leading to status dystonicus can occur in the context of pain from any cause, intercurrent illness, surgical procedures, changes in drug therapy, and possibly emotional factors too. In previously healthy children acute encephalopathy of any cause can also lead to status dystonicus. The exact triggers of an individual spasm, which may include some of these, have not been reported in detail. It is well recognized that in its least severe form status dystonicus causes pain and exhaustion, but that it can also lead to rhabdomyolysis, acute renal failure, respiratory complications, dehydration, and even death. Not surprisingly perhaps there are no generally accepted management guidelines. There are no nationally or internationally approved methods of grading severity, nor any standardized approaches to treatment. For the latter there are a number of proposals incorporating features such as attending to any precipitating cause, especially pain; management of any complications; drugs such as baclofen, benzodiazepines, sedation, clonidine, dopa, anti-muscarinics; followed by increasingly heavy sedation using infusions of, for example, midazolam or chlormethiazole, and finally by intubation, muscle blockade, and ventilatory support.2, 3 In addition, it is recognized that management of the underlying dystonia must be reviewed and that other interventions such as botulinum toxin, intrathecal baclofen, or deep brain stimulation may be needed. However, in some countries many of the drugs listed above are not authorized for the treatment of dystonia.5 Status dystonicus is a treatable condition. It is time that the relevant national or international groups addressed the issues highlighted above, including a formal definition, validated assessment tools, and an agreed approach to treatment. It is also important to ensure that these are then properly translated into practice. Better recognition and treatment will avoid needless suffering.