When a patient presents with a headache and fever how do know if this is something that will go away with Brufen and some rest? If this is the beginning of something more dangerous like bacterial meningitis. Because if we think it’s just flu or something we don’t want to subject the patient to unpleasant tests like lumbar patient to unpleasant tests like lumbar puncture or to radiation from a head CT scan.
Infections that do involve the brain directly like Encephalitis, there will be signs of brain dysfunction. These range from depressed levels of consciousness to decreased responsiveness, inattention, disorientation, and cognitive impairment. In later stages maybe also be a focal neurologic deficit.
Start talking to the patient to assess their level of consciousness and measure their vital signs just like any other acute patient.
If the patient with a headache and fever is not 100% alert, we’ll suspect a central nervous system infection. This may seem obvious, but it is important to mention because when you work in the busy emergency department, you see patients who are not fully alert. You get to see a lot of patients with dementia. So it becomes easy to rationalize signs of encephalopathy and underestimate their significance.
Don’t do this, don’t attribute your patient’s encephalopathy to dementia. Especially if your patient has no history of dementia. Because with this approach, it’s only a matter of time before we make serious mistakes.
So after assessing your patient’s level of consciousness, you do a basic neurological exam to look for focal neurologic abnormalities.
Meningism, Nuchal Rigidity, Brudzinski’s sign
In literature, you’ll find that meningeal signs are mentioned a lot. Whenever you see a patient with a headache and fever, you’ll test for neck stiffness and other meningeal signs. Just be aware of their limitations.
In up to 30% of patients with bacterial meningitis, meningeal signs are negative.
The next stiffness or nuchal rigidity works is when there is meningeal irritation caused by usually
- Infection (meningitis)
- Hemorrhage (SAH)
- Meningeal metastasis.
There is a reflex spasm in the muscles in the neck and this causes resistance.
So, to test for nuchal rigidity, your patient’s spine bend their neck and bend their head forward to see if they can touch their sternum with their chin. If they can’t, this is abnormal and while you are doing this maneuver. If they also bend their hips and knees this is so Brudzinski sign.
If either one of these is positive you should suspect meningeal irritation. But there is another problem with meningeal signs. In elderly patients who have chronic degenerative changes to their cervical spine movement in any direction could potentially be limited.
So do check for the next stiffness in every patient with a fever and headache. Just be aware of these limitations.
Recent Trauma, Otitis Media or Sinusitis
If your patient is fully alert, there is no focal neurologic deficit and meningeal signs are all negative, you still want to know about the time period. Immediately preceding the onset of this headache.
Head Trauma: Has there been any head trauma or some kind of infection? Because if your patient did have a head trauma recently and now they have worsening headache, this could be a sign of an intra-cranial complication like Subdural Hematoma. This is especially common in elderly patients who take anticoagulants. They typically fall they hit their head. Doesn’t seem like a significant head at first. But after several days neurologic symptoms start to appear as a result of this uncontrolled bleeding.
Sinusitis or Otitis Media: If your patient has had symptoms of bacterial sinusitis or Otitis media and now presents with the worsening headache and fever again. You’ll suspect intra-cranial complications like subdural or even venous sinus thrombosis. These patients with vinous Sinus thrombosis and subdural empyema can also have nasty headaches and fever for hours, if not days before they develop depressed levels of consciousness or focal neurologic signs.
Biphasic Disease Resulting in Meningitis or Encephalitis
This period of time right before the onset headache is important for viral infections as well. Here’s what happens:
The first phase of illness may look like a summer flu. So an insignificant viral infection. The patient gets better after a couple of days only to get worse once again after about a week. So this biphasic course of illness is characteristic of some types of meningitis and encephalitis.
So this biphasic illness not to mention that many infections that are otherwise benign in rare cases can cause post-infectious encephalitis. So Encephalitis that happens several weeks after this infection triggers an inflammatory response.
So you should always ask about this time period right before the onset of the headache.
It’s not a CNS infection (probably)
if you find some other logical explanation for your patient’s headache like strep throat or acute pyelonephritis. Patients with all sorts of infections that don’t have anything to do with central nervous can have a very bad headache. Just ask yourself, how sure are you that this is the right diagnosis? What signs and symptoms did you find to support it? And does this exclude the essential nervous system?
It has been seen in countless patients with Encephalitis bacterial meningitis abscesses whose headache or encephalopathy was attributed to a urinary tract infection or pneumonia they didn’t actually exist. All because someone found 16 leukocytes in the urine samples or they saw something that kind of looked like a shadow on a chest x-ray.
If you don’t know what to do consult a senior physician. In practice, there will be cases from time to time when you don’t really think that your patient has an essential nervous system infection. But you won’t have the nerve to send them home either. So you’ll probably admit for observation for a couple of hours. You’ll rehydrate them, maybe give them some antibiotics and then see if they get better. Sometimes this is a rational approach.
However, If this is the primary reason why the patient came to seek medical attention. If it’s the only symptom or the dominant symptom or if it persists for several days. Do that spinal tap and exclude a central nervous system infection. Maybe imaging will be required if you suspect a full Collision like a tumor or ischemia or bleeding. If something seems off listen to your instinct and dig further.
Spinal Tap (Lumber Puncture): Why it’s Essential
A Spinal tap with CSF analysis is the only way to reliably exclude or confirm essential nervous system infection. When doctors see that something is wrong with their patients they do a head CT Scan they find nothing and then they’re done with it. It’s not the central nervous system infection it’s not intracranial pathology.
What are you expecting to find if you suspect meningitis on a head CT scan? You can find complications of meningitis but you cannot diagnose meningitis with a CT scan. Of course, it will come back normal in the majority of cases spinal tap is the only way. It may look scary to someone who doesn’t have a lot of experience with it. But it’s a very safe procedure if done right.
If your patient is awake if they don’t have a focal neurologic deficit, if they are not immunocompromised, if they are not at high risk of bleeding. So they are not anticoagulants or something it’s highly unlikely that the procedure will do them any harm. It’s not exactly pleasant but serious complications are extremely uncommon.
There are countless patients with meningitis and encephalitis who were misdiagnosed and did not receive proper treatment in time because a Spinal Tap was not done in time.
It’s always better to do a Spinal Tap and see there is no meningitis than to postpone it out of fear and then miss a serious diagnosis. If the CSF analysis comes back normal, so negative meningitis or encephalitis.
Most of the time it should come back normal. Remember if you only do spinal tap when you are sure that this is meningitis, you don’t do it often enough. It’s only a matter of time before you miss a serious diagnosis.
Headache and fever in immunocompromised persons
In the end, be careful with immunocompromised patients since their immune response to infection can be blunted their temperature doesn’t have to be all that high their headache doesn’t have to be all that bad. If an immunocompromised patient presents several days of headache and fever always be at least a little bit paranoid assume the worst and exclude essential nervous system infection. Just remember that in immunocompromised patients you have to do a head CT scan before you do lumber puncture.