Febrile seizures: current role of the laboratory investigation and source of the fever in the diagnostic approach.

OBJECTIVE

The aim of this study was to analyze the value of performing laboratory tests, taking cultures, and imaging, a diagnostic approach for febrile seizures (FSs) still routinely performed despite the American Academy of Pediatrics recommendations not to. Another aim of this study was to identify the most common sources of fever in patients with FSs and to determine whether the occurrence of FSs correlates with the seasons of the year.

METHODS

This is a retrospective study that included all patients diagnosed with simple or complex FSs who were seen in the emergency room or inpatient unit from January 2004 to December 2009.

RESULTS

Of the 219 patients included in the study, 135 (61.4%) cases had the etiology of the FS diagnosed. Upper respiratory tract infection, otitis media, urinary infection, and pneumonia were the most common diagnoses attributed to the fever. Leukocytosis was present in 48 (24%) of 219, and neutrophilia in 199 (91%) of 219 cases. Low bicarbonate levels were common among every age group. Only 1 blood culture was positive for Salmonella. The incidence of FS was higher during the winter (49.3% of the cases), and it closely paralleled the seasonal variation of viral infections.

CONCLUSIONS

Even though laboratory tests, taking cultures, and imaging are performed in daily practice when approaching FSs, the association of FSs with serious infectious disease is rare and usually overestimated. The diagnostic approach should be individualized to each case and correlated with available data like that shown in this study. Parents should be educated with the knowledge that the occurrence of FSs tends to be higher in winter.