Status Epelipticus, CJD, and Encephalitis
HIDEInteractive Transcript
0:01
Let's summarize the findings in herpes encephalitis,
0:04
as one of the diagnoses that is going to be
0:07
made pretty much exclusively by MRI scanning.
0:11
The CT scan findings are typically normal,
0:14
because the abnormality is relatively subtle.
0:16
Herpes will present with fever in 90 percent of cases.
0:20
You'll see it in the peri-insular region,
0:22
as well as in the medial temporal lobes,
0:25
as well as in the cingulum on either side of
0:28
the corpus callosum in the medial frontal lobes.
0:31
Hemorrhage occurs in about one-third of cases, and
0:33
it's usually a bilateral, although asymmetric, process.
0:37
Here, we see that the medial temporal lobe looks
0:40
pretty good on the left side compared to the
0:43
right side, but in the peri-insular region,
0:46
we see bilateral disease in this patient.
0:50
Another entity that may lead to
0:52
seizures and fever is this entity.
0:57
So here, we have diffusion-weighted imaging
1:01
showing high signal intensity in the cortex.
1:04
And this is a bilateral process.
1:07
It's a little bit asymmetrical.
1:09
In a patient who is having status epilepticus,
1:13
you can see cytotoxic edema of the gray matter,
1:17
which will reverse without permanent damage.
1:20
So, in a patient who is actively seizing in the
1:24
MRI scanner, has recently stopped seizing,
1:28
or is being controlled in status epilepticus,
1:32
this is a pattern that you may see that is
1:34
limited to the cortex as cytotoxic edema on DWI.
1:41
However, the differential diagnosis includes
1:43
those entities that cause encephalitis,
1:46
which include a number of viral etiologies,
1:49
including things like measles, or mumps, or rubella,
1:54
or other infectious etiologies, West Nile virus,
1:58
etc. All of these can cause cortical edema.
2:02
So the differential diagnosis is: does the patient
2:06
have a primary seizure disorder, and what we're
2:09
seeing is cytotoxic edema secondary to recent
2:12
seizures, or does this patient have encephalitis?
2:17
And we're seeing cytotoxic
2:18
edema because of the infection.
2:20
Obviously, this is easier made by the
2:22
clinicians, because if the patient has a
2:24
fever, we're more likely to have encephalitis.
2:26
If the patient has a known seizure disorder that's
2:29
out of control, or if the patient has stopped taking
2:32
their seizure medications, then that might be the
2:34
reason why the patient is in status epilepticus.
2:38
In this case, I fooled you.
2:41
This is a patient who has
2:42
Creutzfeldt-Jakob disease, CJD.
2:46
CJD is a disease entity that is due to an
2:50
infectious prion particle, and it can lead to
2:55
seizures, fever, as well as acute mental status
2:59
changes and a rapidly developing encephalopathy.
3:04
CJD most commonly affects the cortex.
3:08
And second, most commonly affects the deep gray matter.
3:13
However, sparing of the deep gray matter should not
3:16
dissuade you from suggesting the diagnosis of CJD.
3:21
Unfortunately, at this time in 2021, we really
3:25
don't have any good medication for treating CJD.
3:28
It's just expectant therapy with
3:30
anti-seizure medications, etc.
3:33
So this is a patient who has encephalitis, and
3:36
that encephalitis is what we call a neurodegenerative
3:39
disorder of Creutzfeldt-Jakob disease.
David M Yousem, MD, MBA
Professor of Radiology, Vice Chairman and Associate Dean
Johns Hopkins University
© 2026 Medality. All Rights Reserved.
