Puzzling Paroxysm: From Simple Febrile Seizure to Encephalitis
This month’s case involves a toddler who presented with a common every day history but that quickly went off the rails. This little girl’s run-of-the-mill recent history, likely lulled the physician into believing the patient wasn’t that sick. In retrospect, however, it’s clear that he missed critical warning signs.
This two-year-old girl was initially seen by a physician’s assistant at her pediatrician’s office two days prior to the emergency department visit. The mother told that PA that the child presented with a fever and sore throat. The girl was diagnosed as having pharyngitis and prescribed amoxicillin, ibuprofen, and Tylenol.
The PA rechecked the toddler the next day and told the mother that the girl was improving. However, the parents awoke at 1:00 a.m. the next morning and found their daughter seizing. They called paramedics, who administered diazepam rectally and transported the child to the hospital emergency department. The child arrived at 1:26 a.m. and was seen at 1:39 a.m.
Upon arrival, the toddler’s vital signs were temperature 103 rectal, pulse 143, respirations 20, and pulse oximetry of 97 percent on 70% facemask.
The parents and paramedics all reported that the seizure was initially generalized. After a brief physical exam, the treating physician noted that the girl had a single isolated seizure that lasted 30 minutes and then had right upper extremity focal activity upon arrival to the emergency department. He recorded an altered mental status and a focal seizure, with the girl’s eyes deviating to the right. The physician’s notes included a two-day history of fever, sore throat, and cough.
The toddler was given IV fluids and rectal acetaminophen, and at 2:25 a.m., she had an active focal seizure of the right arm.
At 3:50 a.m., the child was re-examined. The physician’s documentation stated the girl had no evidence of further seizures or meningitis. The physician noted that neither a CT scan nor a lumbar puncture was indicated.
At 6:00 a.m., the child was again examined and “back to baseline.” The seizure was characterized as febrile and discharge orders were placed at 6:02 a.m. Discharge instructions were given to return for fever, vomiting, rashes, seizure, lethargy, or if symptoms worsened. The parents were advised to continue to administer antibiotics as prescribed.
At 7:00 a.m., prior to leaving the ER, the child had a fever recurrence. In response, a nurse administered additional ibuprofen and acetaminophen. The family left the emergency department at 9:01 a.m. and visited the pediatrician two hours later. The physician’s assistant again saw the toddler and diagnosed her with possible pneumonia, pharyngitis, and febrile seizures.
The next day, the girl’s parents noticed their daughter’s lack of energy and called the pediatrician’s office. The office staff advised the family to go to the nearest emergency department. At the emergency department, it was noted that the two-year-old was lethargic. A CT scan was promptly ordered which showed a questionable abnormality in the left temporal lobe. The child then had a lumbar puncture performed, which showed 400 WBCs and 50 RBCs per high power field. In response, the toddler was given antibiotics and admitted to the pediatric intensive care unit.
On the third day of the admission, the girl began having intractable seizure activity. A repeat head CT scan showed a large infarction involving the left middle cerebral artery territory with increased swelling of the left temporal, left frontal, left parietal, and occipital areas. She was then intubated and transferred to a pediatric specialty hospital.
While in the pediatric specialty hospital, it was noted that the child had minimal movement of her right side. Cultures returned positive for HSV and the child was diagnosed as having HSV encephalitis/meningitis. She was left with chronic intermittent seizures and right-sided paralysis.
Both the emergency physician and the medial group settled the case for close to policy limits. The pediatric practice also settled, but for an undisclosed amount. While the case was likely defensible, given the devastating condition of the child the potential damages most likely far exceeded policy limits, thus the decision to settle made sense.
Meningitis and Encephalitis
All infections of the brain can lead to a condition on the continuum between meningitis and encephalitis. Meningitis is defined as an infection of the meninges. Encephalitis is inflammation of the brain and, by definition, associated with some type of neurologic dysfunction. Signs may include altered mental status, unusual behavior, seizures and/or focal neurologic findings. Patients frequently have an accompanying fever, headache, and vomiting.
In one study of patients with encephalitis, approximately 80% of children presented with fever, 80% with seizures, 56% with focal neurological findings, and 47% with a decreased level of consciousness.
A careful neurological exam should be performed on children suspected of having febrile seizures. Special attention should be paid to any focal neurological findings, including flaccidity or increased muscle tone. Other worrisome findings include a vesicular rash, a maculopapular rash, or other signs of infection.
Differential diagnosis of suspected febrile seizures should include brain tumors, intracranial bleed, and metabolic, toxicologic, autoimmune, and infectious causes. Potential infectious agents include bacterial meningitis; viral causes, including Zika, HIV, West Nile, and HSV; central nervous system tuberculosis; fungal; and amoebae.
Eighty percent of febrile seizures are considered simple and consist of a single tonic-clonic episode lasting less than 15 minutes (and most often much shorter). Twenty percent of febrile seizures are considered complex, and may be focal, prolonged, or recurrent. Patients with complex seizures have a greater incidence of complications, therefore, require greater scrutiny and evaluation.
Encephalitis is a clinical diagnosis. Due to the severity and differential diagnosis, extensive testing for encephalitis is usually indicated.
CBC results are rarely diagnostic but certain etiologies may cause neutropenia, thrombocytopenia, eosinophilia, or hyponatremia. For example, HSV may cause neutropenia, thrombocytopenia, and hyponatremia.
CT or MRI imaging should be considered prior to lumbar puncture in all patients, and particularly in those patients with altered mental status or focal neurological findings. With the increased sensitivity of advanced neurological imaging and the broad differential, the diagnosis can sometimes be made prior to the lumbar puncture.
Lumbar punctures may be indicated in patients with deficient immunizations, those currently on antibiotics, those with seizures lasting longer than 15 minutes, or those whose seizures start after the second day of a febrile illness. A lumbar puncture should be performed in all patients with suspected meningitis or encephalitis. The cerebral spinal fluid should be sent for cell count and differential, glucose, protein, Gram stain, bacterial culture, and Herpes Simplex Virus (HSV) polymerase chain reaction (PCR) and enterovirus PCR.
CSF white blood cell count is elevated in approximately 60% of children with encephalitis. The presence of red blood cells may indicate HSV encephalitis or other necrotizing encephalitis. Protein is usually elevated and glucose is usually normal. Interestingly, in 3% to 5% of patients with encephalitis, the CSF findings may be completely normal.
Although not readily available in many emergency departments, an EEG may be useful because it is abnormal in almost 90% of children with encephalitis. Findings are usually nonspecific.
While many lab tests may be abnormal, an encephalitis diagnosis is usually a clinical one. However, since cultures – including PCR results – may be delayed, it is wise to treat all patients with broad spectrum antibiotics and antivirals.
Steroids are not usually indicated, but are considered in cases of severe cerebral inflammation.
A Final Note
It’s important to consider encephalitis and meningitis in sick children – particularly those who have had a seizure and who have a fever. Febrile seizures uncommonly produce focal neurological findings or occur after the first 24 hours of illness. Finally, remember to document a neurological re-examination on all children with a presumed diagnosis of febrile seizure.
The Monster Claim is the nightmare, $1,000,000 plus settlement or judgment (not including defense costs) that could happen to any unsuspecting physician or medical care provider. As in most cases in emergency medicine, it is a case of failure to suspect the diagnosis and involves a series of unfortunate events. We believe that it is important that all emergency providers become aware of these claims so they won’t repeat the same mistakes in the future.