[Noninfectious febrile inflammatory syndromes in children: diagnosis and usefulness of diagnostic procedures].

Objective: To determine the causes and to quantify the benefits obtained from further diagnostic investigations in children presenting with a non infectious inflammatory fever.
Methods: The records of 62 children aged from two-months to 15 years (median: four years) admitted to a paediatric department between 1990 and 2000 for the evaluation of a fever associated to an inflammatory syndrome, defined as temperature over 38 degrees C with an increase of the erythrocyte sedimentation rate (ESR) more than 20 mm/h and/or a serum C-reactive protein level (CRP) > 20 mg/L, and excluding overt infectious diseases, were retrospectively reviewed.
Results: Of these patients, 79% children (49 cases) had inflammatory systemic disease, 3.2% (two cases) had malignancy, and 17.8% (11 cases) had undiagnosed disorders. The most frequent disease was Kawasaki disease (22 children), especially in young children. Increase of ESR above 100 mm/h and of CRP above 100 mg/L was present in 59% of Kawasaki disease, 71% of idiopathic juvenile arthritis, 100% of malignancies and 7% of unknown diagnoses. Increase of ESR below 50 mm/h and of CRP below 50 mg/L was present in 75% of hemophagocytic syndromes and 46% of unknown diagnosis. The polymorphonuclear count, hepatic function evaluation, triglycerides levels, abdominal ultrasound, abdominal computed tomography, echocardiography, biopsies were useful diagnosis tools. Technetium scintigraphy was helpful only when abnormalities were found on physical examination.
Conclusion: The diagnosis of Kawasaki disease must be quickly suspected in febrile young children with inflammatory syndrome without infection. ESR and CRP values, abdominal ultrasound and echocardiography are helpful tools for the diagnostic procedure.