Pseudoseizures–Achieving Accurate Diagnosis

You are called by jail deputies to see a patient who had a short seizure and now is having another. The patient has only been in jail for a couple of days. He did not mention a seizure disorder at booking. He was arrested on a meth charge.

When you arrive, the patient is on the floor of the dorm, unresponsive and twitching. What do you do?

The diagnostic problem here is whether this is a true epileptic seizure or whether this is one of the various kinds of pseudoseizure. Accurate diagnosis is important because the treatment for the two conditions is so different.

Two epileptic seizures in short succession should make you think about status epilepticus and calling an ambulance. Even if the seizure stopped and you didn’t send this patient to the hospital, you would want a detailed examination in clinic to determine why these seizures happened. Is this a manifestation of some type of withdrawal, such as alcohol withdrawal? Does he have a seizure disorder that he did not tell you about before? You might consider a benzodiazepine like Ativan acutely and an anti-seizure drug like phenytoin. Down the road, you might want to do a work up, such as blood work, an EEG and maybe even a specialist referral.

On the other hand, if this is a seizure look-alike such as a Psychogenic Non-Epileptic Seizure (PNES), your treatment algorhythm would look much different. Then, your goal is just to stop the event and hopefully, be able to intervene in some way (counseling?) to prevent these from happening in the future. No ER visit. No seizure drugs. No EEG etc.

To get the diagnosis wrong—either way—would be to treat the patient inappropriately and perhaps even to harm the patient. So, accurate diagnosis is paramount.

It turns out that there are several observations, “field tests” and tools that can be useful in differentiating true epileptic seizures from pseudoseizures. There are even lab tests that can be useful! Some of these are much more reliable and accurate than others and I will point these out. Continue reading