HOT TOPICS

Andrew Lawson, M.D.

HOT TOPICS

1. FEVER PHOBIA

Is a high fever dangerous?

What are the facts:

41c (105.8f) or higher had <3% risk of bacteremia

Of that 3%, >90% bacteremia from Strep. pneumoniae

Over 95% of bacteremia caused by Strep. pneumoniae resolves spontaneously

Although risk of bacteremia DOES increase with height of fever, the risk of serious illness IS NOT dependent on height of fever.

Prevention: correct dosing of Tylenol 20mg/kg

Diagnosis: Fever Phobia (you’re not alone, these stats compare parents to physicians)

12% vs 21% believed fever could cause brain damage

83% vs 91% believed there was a danger from fever

Treatment

Don’t take temperatures

Does fever causes brain damage?

“Many parents fear that fevers will cause brain damage. Brain damage from a fever generally will not occur unless the fever is over 107.6°F (42°C). Many parents also fear that untreated fevers will keep going higher and higher. Untreated fevers caused by infection will seldom go over 105°F unless the child is overdressed, or trapped in a hot place. The brain's thermostat will stop the fever from climbing above 106°F.”

2. FEBRILE SEIZURES

Febrile seizures are a common cause of convulsions in young children. They occur in 2 to 4 percent of children younger than five years of age, but the incidence is as high as 15 percent in some populations. Simple febrile seizures are the most common and are characterized by seizures that last less than 15 minutes.

Febrile seizures occur in children between the ages of six months and six years, with the majority occurring in children between 12 to 18 months of age. They are often seen as the temperature is increasing rapidly but may develop as the fever is declining.

Genetic and familial factors appear to be important factors in the expression of febrile convulsions and the subsequent development of epilepsy in some children. Among first-degree relatives of children with febrile seizures, 10 to 20 percent of parents and siblings also have had or will have febrile seizures.

In addition, previous studies have shown that siblings and parents of patients with febrile seizures have a 4 to 10 percent incidence of epilepsy.

The majority of children have their febrile seizures on the first day of illness and, in some cases, it is the first manifestation that the child is ill. The degree of fever associated with febrile convulsions is variable, and approximately 25 percent of events occur when the temperature is between 38ºC and 39ºC. Recurrent febrile seizures do not necessarily occur with the same degree of fever as the first episode and do not occur every time the child has a fever.

When the only indication for performing a lumbar puncture is the seizure, meningitis will be found in fewer than 1 percent of patients and fewer than one-half of these will have bacterial meningitis.

For children who have had febrile seizures, treatment with antipyretics at the time of a febrile illness is helpful in overall management but does not appear to affect the recurrence rate of febrile seizures

Children with febrile seizures are at risk for developing recurrent febrile seizures. A major factor influencing the recurrence rate is the age of the infant at the time of the first seizure. The overall recurrence rate is approximately 30 to 35 percent. However, the values vary with age from as high as 50 to 65 percent in children who are younger than one year of age at the time of the first seizure to as low as 20 percent in older children.

A prospective cohort study of 428 children with a first febrile seizure defined other features and factors influencing recurrences. Approximately one-third of the children had at least one recurrence, 17 percent had one recurrence, 9 percent had two recurrences, and approximately 6 percent had three or more recurrences. The majority of recurrences (50 to 75 percent) took place within one year of the initial seizure and almost all occurred within two years.

Four factors in the prospective cohort study increased the recurrence risk:

· Young age at onset

· History of febrile seizures in a first-degree relative

· Low degree of fever while in the emergency department

· Brief duration between the onset of fever and the initial seizure.

No difference was found in measurements of academic progress in children with febrile convulsions, whether simple, complex, or recurrent, compared to a controlled cohort.

Epilepsy occurs more frequently in children who have had febrile seizures than in the general population. In a normal child with a simple febrile seizure, the risk is only slightly above that of the general population.

(data obtained from www.uptodate.com)

3. WHAT ABOUT HEAD CT SCANS?

Benefits: Are there really any???

59 of 8000 needed surgery with GCS of 15 (.7375%)

1 in 20 (5%) head CT’s will be abnormal but WILL NOT need surgery

Risks: Are there any???

20 out of 1 million (.002%) who have head CT will develop thyroid cancer in

their life time and of those 20, 2 will die from the cancer.

A statistically significant decrease in high school attendance was seen in groups

receiving a dose of 100mGy to the head or greater –

and the decrease in attendance was dose-related. (Br Med J, Vol 328, January 3, 2004)

A 1 year old having an abdominal CT incurred a life-time cancer mortality risk of 0.18% (1 in 550 persons) (Lancet, vol 363, pg 1178)